The Industrial training was carried out in four different places of attachment. ..... ensured can be divided into the Physical, Chemical and biological parameters. .... maintains over 10000 books and technical reports, 200 journal titles, 2500 special collections ...... Knowledge on carrying out manual labour has been acquired.
GENERAL INTRODUCTION The Industrial training was carried out in four different places of attachment. The first was carried out at Ogun estuary where activities such as identification, collection of data on meristic and morphometric characteristics of fish species and their adaptation features was carried out and knowledge on the fishing gear/craft used by fishermen on the estuary and their livelihood was acquired. The second was carried out at the University farm where pond management activities such as clearing of the grasses on the pond dykes and reservoir walkway, fish feed pelleting, hatchery maintenance and harvest of fish and preservation was carried out. The third was carried out at Adeniran farms where activities such as fish feed pelleting and packaging, feeding of fish and preservation was carried out. The fourth was carried out at the National Institute for Freshwater Fisheries Research where knowledge on almost all the research divisions was acquired.
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BRIEF HISTORY OF OGUN ESTUARY It is an extension of the Lagos lagoon as described by the Nigerian Hydrographic Map. Almost throughout the year, the water has low salinity i.e. almost fresh. It is most of the time as fresh as inland water because it has many freshwater tributaries. There are several landing centres on the estuary which include: Agbelegiyo landing centre, Imobi landing centre, Oriyannu landing centre, Iwopin wharf, Eyindi landing centre and others. Each landing centre has peculiar characteristics i.e. the categorization is based on settlements. At Agbelegiyo landing centre, the people specialize in the use of Gillnets and Atala for capturing Clupeids. They go at night and come back in the morning. The percentage catch on fishing gear basis is 70% Gillnet and 30% cast net. At Iwopin landing centre, fishing is mainly done by using seine nets. The people use big canoes with outboard engines and engage themselves with a lot of labour. The average number of fishermen per operation is two persons. One is to paddle while the other is to cast the net. An average fisherman here lives above one dollar per day. At Imobi landing centre, the people are into Iken (i.e. Brush Park) fishery whereby vegetation is assembled and open at the centre. The type of vegetation used includes: Voscia spp, Strontium spp etc. Harvesting however is laborious. At Eyindi landing centre, the people are into Ifatiko (i.e. cast net) fishery. It is the most active fishery in terms of catch per unit effort (CPUE). The operators are mostly youth. The major problems of Eyindi people are: black water (which is as a result of accumulation of humic 2
substances) which hampers fishing activities, water hyacinth which blocks navigation passage and lack of government support (as in the supply of subsidized outboard engines) Fish species landed: Majorly, Tilapia zillii contributes over 30% of total catch. Tilapia mariae() and Sarotherodon galilaeus () are caught from Iken (Brush Park). Chrysichthys nigrodigitatus (), Heterotis niloticus and Barracuda are also caught.
TRAINING PROGRAMME: The training programme went as follows: ü Fish species identification at each landing centre visited Collection of data on the: ü Meristic and morphometric characteristics of fish. ü Adaptation features of fish especially mouth parts and body shapes. ü Fish species landed at each landing site visited. ü Type of fishing gear/craft used for fishing on the estuary at various landing centres. ü Materials for construction of each fishing gear. ü Livelihood of the fisher folk on the estuary. ü Water quality parameters of the estuary. Familiarization of the: ü Brush Park (Iken) practically 3
ü Fishing gears as they are being used on the estuary. Fish species landed at different landing centres were identified using fish keys and through consultation of the IT Coordinator. The meristic (i.e. the countable parts e.g. the number of rays in the dorsal, anal and caudal fins, number of scales etc.), morphometric (i.e. the measurable parts e.g. standard length, total length etc.) and adaptation features (i.e. mouth parts and body shapes) of fish species landed at different landing centres visited were also collected. The result of the data collected is summarized in Table 1. The type of fishing gear used on the estuary: this is classified based on the named settlements/landing centres and includes: Agbelegiyo landing centre Cast net: The type of fish caught depends on mesh size. 1 finger (i.e. inch) is used to catch Ẹja shakpore, 2 fingers for Ẹja igangan, 21/2-3 fingers for Ẹja ipiya while 4 fingers is used to catch Ẹja lele apeta. Materials for construction: The materials can cost as much as ₦2500 and above. The materials used include rope, netting material either natural or synthetic, sinkers (lead) and twine etc. Mode of operation: Fish is used as bait and the hook is attached to the caudal fin of the fish to catch Ẹja ọsan. Cutlass is used to prevent obstruction like dangerous animals, paddle (Ajẹ/obẹlẹ) is used with 4
the engine powered canoe for navigation and in times of emergency when the engine stops working in the middle of the water. Gill net: Different methods of operation are employed. It can either be set at night and harvested and dried in the morning or set by 5:00am in the morning and harvested by 12:00 noon or 5:00pm depending on the number of fish caught or weather condition. The net can last between 4 months to 5 years depending on its quality. Materials for construction: Osan koko, osan milo, aafi (floater), oje (sinker) Livelihood of fisher folk: The fishermen here are not into full time fishing. Some venture into farming to meet the needs of their family. The educational level here is between not educated to SSCE but they all aspire that all the children go to school. The average income earned here is between ₦500-₦1000 per day. Fish species caught here includes:
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Eyindi landing centre Transport canoe: In its construction hard wood is used. Wood used locally includes: igi ẹru, akoriko, opepe etc. the wood is painted with coal tar to prevent leakage. Materials for construction: Materials for this canoe are different from the one used on sea. Construction can take up to 3 months and the canoe can last between 3 - 4 years before wearing out. Materials used for construction includes: nail (1”,2”,21/2,3”,4,5”,6”), nylon, aluminum pan, Coal tar, wood of 2X6m2 and 1X12m2, net, lead, outboard engine, bolt and nuts. The coal tar is used to block the holes and is coated in 3 layers. 40-60 horse power rating of engine is preferable for the canoe because it lasts longer and has a second hand value compared to the 20hp type. Mode of operation: The transport canoe is used for the transport of people and goods. It is operated with an outboard engine which serves as propeller and the paddle for direction and safe passage on the water. It is usually operated by 4 men per operation. Synthetic monofilament gill net (Awọ): It consists of netting material, cut slippers to serve as floater and stones to serve as sinker. It catches more fish than cotton nets because it is not visible to fish in water. The disadvantage is that it is not durable. A mesh size of 21/2 fingers can capture Tilapia (Ẹja Ipiya).
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Mode of operation: It is set in water for certain duration of time not more than 24hrs before being harvested and dried. Bamboo traps (Apaye): They are used alongside Iken. The Fish residing under the Iken (Brush Park) move to the Apaye as abode. The Apaye itself consists of bamboo (Aparun) with cut out holes in them. It catches fish alive. Fish species such as Cynodontis spp and Chrysichthys nigrodigitatus are caught. Livelihood of fisher folk: The fisher folk here live comfortably, earn above ₦500 per day, believe in education and send their children to school. The jobs here vary from fisherman to food seller to net maker to canoe maker etc.
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Ilamo landing centre Canoe: it is measured in ika (arm length). Canoe length ranges from 3 ika and above based on specifications. It can be constructed in 3 days. It can take a maximum of 10 passengers. It costs between ₦30000-₦50000 to construct. Mode of operation: It is usually operated with 20hp outboard engine but is compatible with other higher engine ratings. When used for fishing is operated by two persons per operation. However because of its relatively small size when used for transport of goods only purpose can be operated by one person. Livelihood of fisher folk: The fisher folk here major in fish processing/preservation i.e. smoking. The freshly caught fish are degutted, washed, salted and then smoked using the traditional drum kiln. The smoked fish are then taken to the market for sales. The fish species mostly smoked are those from the cichlid family. Education ranges from not educated to Primary school certificate. Majority of fisher folk here are Muslims. Other occupations range from food selling to tailoring to garri processing.
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Iwopin landing centre: The fish is landed in the early hours of the morning. Fish mongers buy from the fishermen and resell to wholesalers who then resell to retailers before it gets to the consumer. Livelihood of fisher folks: Fishermen here make use of outboard engines in their fishing activities. Fisher folks here are in part time fishing. They venture in farming and other businesses when there is low catch and 11
return to fishing only when assured of high yield in catch. Fishermen earn between ₦500₦1500 per day.
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A voyage was conducted by the IT Coordinator Dr Waheed Oyebanjo Abdul and his assistant Mr. Deji. Students were instructed to converge at Iwopin wharf not later than 8:30am. Students were advised to eat light meals so as not to get irritated in the canoe. Prayer sessions were held for success of the voyage. At exactly 10:05am, the transport canoe started moving. It’s course was northwest of the landing centre. The IT Coordinator explained the different features found on the water, carried out water quality assessment on water surrounded by vegetation and in open water and carried out depth measurement of the estuary as the canoe moved on. The summary of the explanations/discussions and observations are as follows: The Brush Park was noticed and observed. It comprises of two different species of plants which includes: Strontium spp (the plant longer with adventitious roots) and Voscia spp (the shorter plant). Bamboo is used to hold down the Iken so that it doesn’t get destroyed or move away as a result of storm events. The open water in Iken is used to monitor water to allow for photosynthesis and dissolved oxygen replenishment (Euphotic zone). The root of the soil has soil components which allow the grasses to stand like an island. It takes several weeks to construct the Iken. Iken are arranged so as not to disturb navigation. The fish catch gotten from 13
Iken is better by far than the catch in open sea. This is because the Iken water is richer in organic substances, plankton population, the water is cool and because there is sense of security. When harvesting, the Iken is surrounded with Ẹfọn (a mat-like structure) to prevent fish escape. It is then surrounded with surrounding net to prevent the escape of fish species like tilapia (Ẹja Ipiya) that like to jump. Whenever Iken is being cut, another boat moves the Iken to the shore so as not to disturb navigation. Women were noticed on a canoe. The women capture prawn using small non return valve traps with cassava as bait. Marks were noticed on the water. A mark is used to indicate areas where prawn is caught. This marks serve as buoys. The water quality parameters of water with vegetation and water in the open were collected and the result is as follows: Source
of
water Temperature
pH
Conductivity
Total (ppth)
collected:
(0C)
(µs)
Water in open sea.
31.6
7.6 0.11
0.05
Water with Vegetation.
31.3
7.8 0.16
0.08
The depth of the water was measured and was found to be 1.78m
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dissolved
solids
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PROBLEMS ENCOUNTERED: ü High cost of cooked food where the industrial training took place. ü Inadequate transport system to the landing sites hence the team becomes exhausted before the work at hand is carried out.
HOW THE PROBLEMS WERE SOLVED: ü The IT team contributed money and hired a cook to buy foodstuffs and cook for the team. ü The IT team decided to have an afternoon break for rest. Hence two sessions of data collection was carried out. The first session beginning by 8:00am in the morning and the second session by 1:00pm in the afternoon.
PHOTO SHOTS:
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RECOMMENDATION ü The University should provide future IT students with free transport and accommodation in places of attachment under the school’s Coordination. ü The University should ensure in the future that IT Coordinators and Supervisors are well funded and taken care of. ü Industrial attachment at the Ogun estuary should be continued for other sets of students because there is a lot of aquaculture potential there still waiting to be tapped.
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ü The Department should lobby that more money is sent into research especially in the area of the use of cage culture in Ogun estuary to produce a lot of fish thereby combating malnutrition and utilizing Nigeria’s water resources more effectively and efficiently.
CONCLUSION The Industrial training that was carried out at Ogun estuary is a foundation for those that aspire to further on fisheries biology and statistics. The industrial training has made a lot of the theory learnt in class more understood. Almost all the fishing gears that were learnt in the theory have been seen and familiarized in the practical. Moreso, identification of fish species based on some characteristic features learnt in the theory have also been identified and established in the practical.
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BRIEF HISTORY OF THE UNIVERSITY FISH FARM The University fish farm is a specialized fish farm into production of all year round food fish. The University fish farm consists of the hatchery building, reservoir, earthen ponds, concrete tanks, and Glass Reinforced Plastic tanks (GRP) and the smoking kiln house. The University Fish farm gets its source of water from the reservoir and from borehole. The UNAAB reservoir: It was mechanically constructed (with the use of bull dozers and compactors) in the year 1999 basically for storage of water for irrigation purposes. Presently, the UNAAB reservoir not only serves as an all-year-round water supply but is used to rear fish extensively. It gets its source from the river Alabata and supplies the earthen ponds through underground channels. It also supplies the concrete tanks with water. The UNAAB Hatchery: This was commissioned by the former President Olusegun Obasanjo and funded by Education Trust Fund (ETF) 2002. Water is supplied to the hatchery from boreholes pumped into large overhead storage tanks. It is left to cure for two days before being considered fit to use.
TRAINING PROGRAMME The training went as follows: ü Hatchery maintenance. 23
ü Smoking house maintenance. ü Fish harvest and preservation. ü Knowledge on pond management technology. ü Pond management. ü Fish feed pelleting. ü Sorting of fish for Jumpers/shooters and removal of tadpoles. Hatchery maintenance: This was done by sweeping the floor of the hatchery building, washing the tanks with soap and clearing the vegetation around the hatchery. Smoking house maintenance: This was done by sweeping the floor and removing charcoal fragments. Fish harvest and preservation: Fish was harvested with drag nets from the earthen pond and concrete tank while plastic bowls were used to harvest fish in the fibre glass tanks. The harvested fish were degutted, rinsed with clean water, salted, rolled circularly and put on the trays of the smoking kiln and then smoked. Pond management technology: This is the process by which the effective and profitable running of a fish farm is ensured. Types: ü Water quality management. 24
ü Pond management. Water quality: This is the degree of excellence that is given to a body of water. The growth of fish is dependent on the water quality and quantity. The most important water quality to be monitored and ensured can be divided into the Physical, Chemical and biological parameters. Important Water Quality parameters include: 1. Temperature: - it is very important in fish production. It is a limiting factor in fish production and very important in determination of fish to be cultured. It can be measured with the thermometer. The impact of temperature on fish production is summarized below. A very high temperature may affect the pond fish resistance to disease pathogens. Minimum temperature should be between 230C - 240C and the maximum should be 320C. It affects the level of Dissolved Oxygen in the pond. Dissolved oxygen decreases with increase in temperature level since oxygen consumption increases with rising temperature. 2. Turbidity: - this refers to the water content, suspended materials which interfere with the light passage into the water column. Good water turbidity helps in eliminating troublesome water weeds. Good plankton turbidity also favours greater fish production by simulating the growth of fish food organisms. Turbidity ranges from 30 - 60cm and is measured with secchi disc.
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3. Dissolved Oxygen: - it is a critical factor in fish culture. The success of any fish farm operation depends on the farmer’s ability to cope with the problem of low dissolved oxygen. Excess decomposition of organic matter , high presence of aquatic weeds and undesirable plankton bloom can lead to the problem of dissolved oxygen shortage. Low dissolved oxygen can be corrected by aeration of the water body by either stirring or reducing and topping of water with a fresh one. 4. pH: - this measures the level of alkalinity or acidity of water. 6.5 - 9.0 is regarded as the best for fish production. The level of pH is usually obtained through the application of the right amount of lime and effective fertilization. It can be measured using the pH scale. Pond management It takes place after construction. It is important in order to ensure the durability of the pond. It involves maintenance of pond environment and the pond itself. It involves taking care of inside the pond and the surroundings. Procedure involved in pond management: 1. Weed control. 2. Pond bottom restoration (Desilting). 3. Predator control. 4. Liming and fertilization.
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The pond should always be in right condition for fish production. The aquatic weeds should always be controlled or prevented from taking over the pond. The pond should always be free of aquatic weeds because it could be a hiding place for snakes. The dyke vegetation should be regularly cut. Predators should be eliminated from the farm. Liming increases the pH of the pond bottom and puts in essential minerals in the pond. Fertilization increases the primary productivity of the pond. It provides the essential minerals, nutrients such as Nitrogen, Phosphorus and Potassium for rapid development of phytoplankton. It improves the hygienic condition of the pond. Inorganic fertilizer acts faster than organic fertilizer hence lesser quantity is required. Pond management: This was done by clearing the dykes of the reservoir, clearing the dykes of earthen ponds, and desilting the earthen ponds. Fish feed pelleting: This was carried out in the hatchery building. The already mixed feed ingredients were poured onto the pelleting machine and long threads (looking like Kulikuli) came out of the machine. The feed pellets were taken outside for sun drying. Sorting of fish for Jumpers/shooters and removal of tadpoles: This was carried out on a counting board. The counting board consists of a plain smooth surfaced rectangular piece of wood with two round holes at the opposite extremes. It is used for sorting and counting fish such as fingerlings and juveniles. Sieve was used to pick fish from a 27
plastic container holding harvested fingerlings onto the counting board. Fish were counted and sorted from tadpoles at the same time. The fingerlings and tadpoles look alike physically. The major method of differentiation is that tadpoles have bigger head and are calmer while fingerlings are very agile.
CONCLUSION The industrial training has enabled me to become a better manager of ponds. It has given me basic knowledge on pond management and maintenance.
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BRIEF HISTORY OF ADENIRAN FARMS Adeniran farms is situated at Coker Street, Abisi village, behind Abesan estate, Lagos state. It is run by Mr. Adeniran himself. The farm staff is made up of Mr. Adeniran (Manager), his son Bayo Adeniran (Assistant Manager), his relative Lanre (Farm assistant). The manager is a civil servant (secondary school teacher). The manager started in the year 2009 with just one undrainable earthen pond. Now he controls 3 drainable earthen ponds (each with an area of 10x15m2) and a feed mill (consisting of a large NEPA powered grinding machine and a feed pelletizing machine).
TRAINING PROGRAMME The training programme is as follows: ü Feeding of fish ü Fish feed pelleting ü Pond management Feeding of fish: This was usually done in the early hours of morning and in the evening when the sun is down and temperature is lower. The fish were fed with 2mm formulated feeds. Point feeding was employed here and fish were fed at the deepest part of the pond just in front of the outlet. Fish feed pelleting:
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The procedure that was carried out in fish feed pelleting is as follows: The already measured ground feed ingredients were poured on each other on the clean floor and mixed together with the aid of shovel such that the distinctive colours of the various feed ingredients mixed was no longer noticed. The feed ingredient mixture was then mixed with palm oil in a plastic bowl before being mixed with the starch which acts as a binder to prevent the leaching away of feed nutrients. The starch was prepared by putting raw starch powder into hot water and mixing with cold water so as not to injure/hurt the feed pelleting operator during mixing. The feed ingredient/starch mixture was then put into the pelleting machine to be converted to pellets. The pellets were then sun dried to prevent entry of antinutritional elements. Pond management: This was done by clearing the pond walkways and manually removing some of the aquatic vegetation present in the ponds. The activity was set to be done every 2 weeks. The clearing was very laborious.
PROBLEMS ENCOUNTERED: ü The knowledge/experience acquired was comparatively little. ü The manager was not usually around to teach. ü The work most of the time was on feed pelleting.
HOW THE PROBLEMS WERE SOLVED:
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ü Knowledge was acquired from observations of the industrial processes. ü While working on the farm, an alternative place of attachment for industrial training was searched for. CONTRIBUTION TO THE FARM: ü The duck weeds that were a menace in the earthen ponds was manually cleared so as to ensure good primary productivity and somewhat stable dissolved oxygen level in the water.
PHOTO SHOTS:
CONCLUSION Knowledge on general pond management practices was acquired. The various theoretical guidelines for managing a successful fish farm were put into use. There was harmony in what was learnt in the theory with what was practiced in the practical. 31
BRIEF HISTORY OF THE NATIONAL INSTITUTE FOR FRESHWATER FISHERIES RESEARCH (NIFFR) The Institute is situated along Mokwa road, New Bussa, Niger state. It was established in 1968 as Kainji Lake Research Project by the Federal Government of Nigeria with the assistance of UNDP (United Nation’s Development project) with an arm, FAO (Food and Agriculture Organisation). UNDP assigned some FAO officials to administer the project. In 1975, the FAO withdrew their experts and the project became a fully fledged Institute with qualified Nigerians at the helm of office. It then came to be known as Kainji Lake Research Institute. It was departmentalized into fisheries, limnology, public health, socioeconomics, and wildlife ecology and range management. However, as a result of the re-organization of some research institutions in 1987, the mandate of the Institute was changed from the multi-commodity KLRI (Kainji Lake Research Institute) to mono-commodity research based on freshwater fisheries and aquatic resources generally with emphasis on hydrology, Fisheries biology, Limnology, Environmental studies, Fisheries technology, Hatchery management, Aquaculture, Socioeconomics, Extension liaison services and training. The name was changed to NIFFR (National Institute for freshwater fisheries Research) and the mandate to research on freshwater fisheries and other aquatic resources in the water to sustain the Nigerian populace.
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NIFFR ORGANOGRAM
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SCHEDULE OF ACTIVITIES PROGRAMME Introduction Coordinator
of
NIFFR
by
HEADS PROGRAMMES
SIWES 1st June, 2011
Mr. Jude Nnaji
2nd - 3rd June
Library Integrated fish management
DATES
farming
and
th
Dr M. Ibeun
th
pond 6 – 17 June
Dr V. Omeje
Hatchery
20th June – 15th July
Dr V. Omeje
Biotechnology
18th July – 15th August
Dr Moses Yisa
Fish Nutrition
8th August – 12th August
Dr (Mrs.) Ovie
Fish Products Development
th
th
Mr. Emeka Ugoala
th
th
15 August – 17 August
Fish Preservation
18 August – 19 August
Mr. Ezekiel Adelowo
Fish Quality and Storage
22nd August – 24th August
Mr. J. Umalu
Aquatic Pathobiology
25th August –26th August
Dr Oscar
Fisheries Biology
29th August –31st August
Dr W. Omorinkoba
Fisheries Statistics/Gear
1st September September
–
5th Dr J. Abiodun
Limnology
6th September September
–
9th Sir B.C. Azionu
Pollution Studies
12th September September
–
14th Dr I. Mbagwu
Aquatic Vegetation
15th September September
–
19th Mall. Y. Yauri
Fisheries Economics
20th September September
–
21st Mr. G. Nwabueze
Fisheries Extension
22nd September September
–
23rd Rev. Olowosegun
Rural Sociology
26th September September
–
27th Mall. S. Omeiza
Exit session SIWES Coordinator
28th September
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Dr Olufeagba
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THE LIBRARY PROGRAMME BRIEF HISTORY: The NIFFR library is a specialized library specifically for fisheries and aquatic sciences. It maintains over 10000 books and technical reports, 200 journal titles, 2500 special collections on Nigerian fisheries and aquatic sciences and 521 theses on all the different facets of fisheries and related disciplines. The library uses the Universal Decimal Scheme for the classification of books and other library materials. It is an ASFA (Aquatic Sciences and Fisheries Abstract) centre for FAO. The service of the library is computerized using the CD/ISIS. All materials published on work done in Kainji Lake are categorized under KANJIANA while publications on fisheries articles in NIFFR are called NIFIC. The services of the library are open to scientists and students both nationally and internationally. The library coordinates the production of the Institute’s Newsletter and it’s dissemination. The management hierarchy of the library is as follows:
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ACTIVITIES CARRIED OUT: ü Knowledge of the brief history of the Institute was acquired. ü The use of the Library was practiced. ü Internet search of the library database was carried out. ü Research Journals were read to find out about recent advances in Fisheries and Aquaculture. ü Newsletters of the Institute and other allied organizations were read.
INTEGRATED FISH FARMING AND POND MANAGEMENT PROGRAMME It is a programme under the Aquaculture and Biotechnology division. This programme is into integration of plant and other animals with fish farming. It comprises of different units and they include: INTEGRATED FISH CUM RICE UNIT This is the cultivation and rearing of fish with rice in the same enclosure. In this system, fish are fed with compounded feeds. The ponds are fertilized for proper growth of rice stems and to promote primary productivity. The NIFFR fish cum rice unit ponds are 10x10m2 in area each and are ten in number. The average depth from the furrows to the top is 0.5m and the width of the furrows is 0.5m while the water level allowance on top is 0.3m. 20 rows of rice stem are planted per 10x10m2 pond. Water is not allowed to completely cover rice so that the plant can photosynthesize and also that fish do not eat and damage the plant.
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The rice plant takes up to 3 months to mature hence can be harvested with fish especially when the fish stocked were post-juveniles. ADVANTAGES OF INTEGRATED FISH CUM RICE FARMING ü More profit is made ü Land is used more efficiently ü There is reduced risk in the sense that the success in one can alleviate the failure of another. DISADVANTAGES OF INTEGRATED FISH CUM RICE ü Skilled personnel is required ü The rice plant could harbor pests and diseases that could lead to fish kill. INTEGRATED FISH CUM POULTRY UNIT The NIFFR fish cum poultry unit occupies a 1.5ha reservoir. The fishes in this system are not fed but are allowed to feed naturally. The water is fertilized by the direct droppings of the poultry birds in poultry cages above the water. The number of birds required to successfully fertilize a water body is 600 birds/ha. Hence 900 birds are required to successfully fertilize the reservoir of the NIFFR fish cum poultry unit. The capacity of the NIFFR fish cum poultry unit however is 580 birds. The loss in manure is compensated with cow dung from cows that graze on the weeds inside the reservoir. It has been estimated from experience that 200 mature birds will feed on 25Kg of feed/day and the 25Kg bag of feed costs ₦1000 ADVANTAGES OF INTEGRATED FISH CUM POULTRY 38
ü There is reduced risk ü Cost of production is reduced i.e. cost of feed, fertilizer etc. (since the droppings and feed spillages of the birds fertilizes the ponds). ü Labour is used more efficiently. ü Land is used optimally. ü More profit is made. DISADVANTAGES OF INTEGRATED FISH CUM RICE ü It is capital intensive to start. ü It requires skilled labour or expert. ü It is time consuming. CAGE CULTURE UNIT Cage culture involves the rearing of fish in cages. Types include the floating and fixed cage types. FACTORS TO CONSIDER BEFORE STARTING CAGE CULTURE These include: ü Amount of capital. ü Area to culture fish. ü Marketability of fish cultured. ü Distance of cage culture site from home. ü Security of cage. 39
In the floating type of cage culture, the cage is tied to a floating raft for rearing of fish. It is mainly used for production of fry to fingerlings. MATERIALS FOR CONSTRUCTION Bamboo/hollow pipe/PVC pipe/straight stick, Kurallon rope, 6” nail, saw, hammer, plastic drum, synthetic netting etc. In the fixed type of cage culture, the cage is put at the bank at mid depth and is tied to sticks on the dyke. It is mainly used as a juvenile growout enclosure. MATERIALS FOR CONSTRUCTION Hyper net or table net is used in its construction. SPECIES OF FISH THAT CAN BE CULTURED IN CAGES These include: Moon fish, Slap water fish, Tilapia and Catfish species etc. MANAGEMENT/MAINTENANCE TECHNIQUES FOR CAGE CULTURE ü Wear and tear should be checked. ü Security in and around the cage culture site should be ensured. ü Labour must be available. ADVANTAGES OF CAGE CULTURE ü Easy to feed and harvest. ü 100fish/m2 can be stocked as against 50fish/m2 in others.
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DISADVANTAGES OF CAGE CULTURE ü Since easy to harvest hence can be stolen easily. ü Technical knowhow is needed.
SPECIES OF FISH CULTURED AT THE INTEGRATED FISH FARM They include: ü Oreochromis niloticus ü Sarotherodon galilaeus ü Tilapia zillii ü Oreochromis aureus ü Clarias gariepinus ü Clarias angulliaris ü Heterobranchus longifilis ü Heterobranchus bidorsalis ü Heterotis niloticus ü Citharinus citharus ü Cyprinus carpio ü Lates niloticus
PROBLEMS ENCOUNTERED ON THE INTEGRATED FISH FARM: ü Parasites such as leeches.
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ü Predators such as Monitor lizard. ü Monk failure. ü Eroded dykes.
HOW THE PROBLEMS WERE SOLVED: ü The leeches were exterminated with formaldehyde. ü Wire trap was set for monitor lizard. Also, hook and line with frog as bait was used to capture monitor lizard. ü Some parts of the failed monk structure were filled with concrete to stop seepage. ü The eroded nature of the dykes was as a result of livestock trampling on the dyke while grazing. Livestock were prevented from entering the reservoir and the eroded parts were reinforced with broken blocks and concrete.
ACTIVITIES CARRIED OUT: ü Harvesting, stocking and restocking of reservoirs were carried out. ü Identification of fish species was carried out. ü Identification of sex in Oreochromis niloticus was carried out. ü Management/maintenance of the integrated fish farm was carried out. ü General pond practices, management and care were learnt.
PHOTO SHOTS:
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HATCHERY PROGRAMME This is a programme under the Aquaculture and Biotechnology division. The building was officially commissioned by General Ibrahim Badamasi Babangida (President Commander in chief of the armed forces of the Federal Republic of Nigeria) on Thursday 22nd November, 1990. The NIFFR hatchery is into production of fry and fingerlings for internal research purposes and for commercial fish farmers. The NIFFR hatchery is a specialized hatchery with modern state of the art facilities which include: the indoor Water Recirculatory System (WRS), outdoor Water Recirculatory System (WRS), indoor concrete fry tanks, indoor concrete growout tanks, outdoor concrete tanks, aerators, hose, and overhead storage tanks etc. The NIFFR hatchery staff consists of a manager, 4 staff, 3 corpers and 2 farm lieutenants.
ACTIVITIES CARRIED OUT: ü The WRS was familiarized. ü Collection of Zooplankton to feed fry in the indoor hatchery was carried out. ü Sorting and sampling of fish was carried out. ü Hatchery maintenance/management was carried out. ü Hatchery operation was carried out. ü Knowledge on successful hatchlings survival procedures was acquired. Description of the WRS The Water Recirculatory System consists of the Culture tank, water storage pump tank, biotower, the sedimentation tank, and the UV filter all connected in a cycle. 47
Normally, water is pumped from the storage tank to the biotower which passes to the UV filter and then moves to the culture tanks. On return after being polluted, the water moves to the sedimentation tank then passes back to the storage tank. The biotower is a biological filter that contains nitrosomonas and nitro bacteria which converts harmful nitrates to nitrites which in low concentrations is not harmful to fish. The UV filter kills the microorganisms in water with ultraviolet rays. The sedimentation tank removes the waste metabolites present in the water. Procedure for collection of Zooplankton: The Zooplankton culture tank is trawled with plankton net either vertically or horizontally to collect Zooplankton into a holding bucket. The Zooplankton is usually collected with dirt, manure, debris, mud, vegetation etc. Since the Zooplankton collected is not pure, it is hence sieved with a hand sieve to remove impurities. Yet, mud is not still eliminated. To eliminate the mud, the resulting mixture is re-sieved with the plankton net to drain out the mud and isolate the Zooplankton. Procedure for carrying out sorting and sampling of fish: Fish is harvested with drag net into a big holding container of water. Sieves are then used to sort and separate the big fish from the small fish. The big fish are the Shooters/Jumpers and are voracious eaters, are good potential broodstock and grow faster. The small and big fish are then placed in separate enclosures. Sorting and sampling is a good management practice that
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reduces cases of cannibalism in fish, gives a fish farmer an idea of growth response of fish to feeding and prevents/reduces possible losses. Procedure for hatchery maintenance/management: This is done by mopping the hatchery floors, brush washing the outdoor hatchery concrete tanks, brush washing the indoor hatchery concrete tanks, clearing the hatchery surroundings, siphoning out dirt, mud, debris etc. from the fry tanks (nursery), washing of materials used for hatchery operation, and servicing of the aerators and hatchery generator. Procedure for hatchery operation: Before the hatchery operation proper takes place, some steps must be taken such as: preparation of the nursery tanks for hatching (by washing thoroughly with brush, broom and sponge without soap the tank to be used), selection and segregation of broodstock, preparation of hormone/injection of broodstock (usually at 9:00pm prompt), preparation of the hatchery operation tables, preparation of saline water, sterilized plastic bowl and spoon, dissecting kit and Kakaban to be used for the hatchery operation. The sterilized plastic bowls and spoons were placed on the readied spawning tables. Saline water, blade, towel and Petri dish were also placed on the tables. There were four groups each having their own pairs of brood stock and hatchery materials during the hatchery exercise. The hatchery operation went as follows; The male broodstock was brought out from the holding container. Towel was used to hold, support and wipe the body of the male. Blade was used to dissect the fish longitudinally to 49
remove the milt sac. The milt sac was placed in Petri dish for a group member to lacerate. The sacrificed male broodstock was placed into an empty container and left aside. The female broodstock was brought out from the holding container. Towel was used to hold and wipe the body of the female of water to prevent entry of water in to the eggs while stripping fish. The female fish was stripped of eggs into the sterilized plastic bowl. This was done by pressing gently the abdomen of fish down towards the genital orifice. Little quantity of saline water was added to the milt in the Petri dish. The resulting mixture was consequently added to the eggs in the sterilized plastic bowl. The sterilized plastic spoon was used in stirring the eggs and milt together. This was done for about 2 minutes after which the mixture was decanted. This was done by diluting with water to reduce the salt content. The mixture was poured in a zigzag manner onto the already prepared Kakaban in the culture system and was left to hatch.
PROBLEMS ENCOUNTERED IN THE HATCHERY: ü Mass mortality of early fry in the indoor hatchery.
HOW THE PROBLEMS WERE SOLVED: ü The mass mortality was caused by over stocking of early fry in nursery tanks. Hence, over stocking of early fry in future was avoided.
PHOTO SHOTS: 50
51
52
53
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BIOTECHNOLOGY PROGRAMME This is a programme under the Aquaculture and Biotechnology division. Biotechnology is the manipulation of biological organisms to make products that benefit human beings. Biotechnology contributes to such diverse areas as food production, waste disposal, mining, and medicine. The aims and objectives of biotechnology includes: proper identification of local species, production of fast and faster growing fishes, production of highly resistant fishes in adverse condition and for characterization of local species etc. The biotechnology building was officially commissioned by Professor B.O. Solomon (Director General, National Biotechnology agency, Abuja.) on Thursday 10th June, 2010. The NIFFR Biotechnology laboratory is a specialized laboratory for the production of transgenic fish. The facilities here include: The Water Recirculatory System (WRS), cold shocking and warm shocking machine, Photomacroscope, Aquaria, eggs dispenser etc.
ACTIVITIES CARRIED OUT: ü Familiarisation of Biotech facilities was carried out. ü Tank preparations were carried out and harvest/restocking of 6month old tetraploid Oreochromis niloticus from laboratory aquaria to outdoor biotech concrete tanks. ü Identification of Tilapia fish species was carried out ü Identification of sex in Tilapia fish species was carried out. ü Identification of Catfish species was carried out.
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ü Practical on production of diploid (2n), triploid (3n), tetraploid (4n) and hybrid catfish was carried out. ü Biotech laboratory maintenance/management was carried out. The facilities familiarized include the: WRS, Photomacroscope, Aquaria and the Aerators.
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Procedure for tank preparation: Washing of outdoor concrete biotech tanks was carried out. This was done with the use of brush and broom to scrub the tank of dirt and opportunistic undesirable algae. The tanks were thoroughly washed and the dirt was swept with broom towards the outlet to make the tanks completely clean. 6 month old tetraploid fish (Oreochromis niloticus) were harvested from laboratory aquaria, their sexes were determined and information about their weight and lengths was collected. The harvested genetically modified 4n fish i.e. tetraploid fish after the collection of morphometric characters were restocked into the already prepared outdoor concrete biotech tanks separately by sex. Procedure for identification of Tilapia fish species: The tail region is usually used to identify fish under the family Cichlidae. A tail with straight bans and sometimes pinkish colouration at the tip of the tail represents Oreochromis niloticus while
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a plain tail with golden colour spots represents Oreochromis aureus. Not to be too theoretic, sketches of the differences in body features is as follows: Procedure for sexing of tilapia: When sexing matured fish one just needs to press the stomach so that eggs or milt will flow. However, if one doesn’t want to stress the fish or the fish involved is immature one could use special markers to mark the genital area so as to see the holes more clearly without necessarily handling fish for too long. If the special markers are not available, one could use food colouring (blue preferably) as markers too. The number of holes of Tilapia is 3 when female and is 2 when male. Procedure for identification of Catfish species: Heterobranchus longifilis takes between 8-12 months to attain maturity. It has a black spot at the posterior end of the adipose fin. The eggs are usually blackish or dark green. The dorsal adipose fins are equidistant. Heterobranchus isopterus takes 1 year and above to attain maturity. The dorsal adipose fin is not equidistant but from a distance can be assumed so. Heterobranchus bidorsalis takes 2 years and above to attain maturity. It has a peculiar pinkish colouration. The adipose fin is shorter than the dorsal fin. The eggs are usually yellowish in colour. Clarias species are differentiated by the vomerine teeth.
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Clarias gariepinus Clarias angulliaris Clarias lazora Generally, the head of Clarias is elongated while that of Heterobranchus is flattened. Procedure for production of transgenic fish The IT team consisting of students from Michael Okpara University of Agriculture, Umudike (MOU); University of Ilorin (UNILORIN), Delta state University (DELSU), University of Agriculture, Makurdi (UAM); Ibrahim Badamasi Babangida University (IBB University), Lapai; Bingham University, Karu;; Usman Danfodiyo University, Sokoto (UDUS); Olabisi Onabanjo University (OOU), and University of Agriculture, Abeokuta (UNAAB) were split into 4 general groups for the practical. Each group to handle one of the four fish hatchery exercises. For the diploid group, Clarias gariepinus male and female were crossed together (Normal fish i.e. 2n) and normal hatchery procedure was carried out. For the hybrid group, Heterobranchus bidorsalis male and Clarias gariepinus female were crossed to give Clariabranchus spp. (It was said that the right way of naming hybrid fish is the use of female generic name followed by the male generic name as in Claria-Branchus not Hetero-Clarias). For the Triploid group (3n), normal Clarias gariepinus male and female was selected (i.e. diploid). The female was stripped of eggs into a clean Petri dish while the male was dissected
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and the testis removed into a Petri dish for a group member to lacerate. Saline water was added to the resulting mixture and then mixed with the collected eggs in the Petri dish by gently shaking the egg milt mixture in the Petri dish sideways. The resulting mixture was then allowed to fertilise for 2 minutes. After the two minutes had elapsed, the fertilized eggs were put into the already set Cold Shocking Machine and was cold shocked for 40 minutes at 50C. After the 40 minutes had elapsed, the eggs were removed and replaced on a Kakaban inside a water oxygenated aquaria and was left to hatch. For the tetraploid group (4n), the opposite of what was done by the triploid group was carried out. In this case, the fertilized eggs were put onto the Kakaban in a water oxygenated aquaria and was left for 40 minutes. After the 40 minutes had elapsed, the fertilized eggs was removed from the aquaria and transferred to the cold shocking machine to be cold shocked for another 40 minutes at 5 0C. After the 40 minutes had elapsed, the cold shocked fertilized eggs were then 1
replaced into the aquaria for hatching. Note: the reason for cold shocking in the Triploid group is so that the eggs will retain their polar cap while in the Tetraploid group is so that the shedding of chromosomes is prevented. Procedure for Biotech Laboratory maintenance/management: These include: collection of Zooplankton to feed transgenic fish in the aquaria, mopping of the biotech floors, clearing of hatchery operation tables, washing of dirty aquaria, filling of aquaria with water, setting up of aeration facilities, brush washing of concrete biotech tanks, etc.
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PROBLEMS ENCOUNTERED IN THE BIOTECHNOLOGY UNIT: ü Mass mortality of transgenic fish in the aquaria
HOW THE PROBLEM WAS SOLVED: ü Water quality was ensured.
FISH NUTRITION PROGRAMME This is a programme under the Aquaculture and biotechnology division. The nutrition unit of NIFFR is into formulation, preparation and testing of artificial feeds. Studies are carried out here on nutrient requirements of fish, Fish feed ingredients/ feedstuffs quality and usage, nutrient digestibility of fish and fish feed formulation and manufacturing.
ACTIVITIES CARRIED OUT: ü Knowledge on Nutrition generally was acquired. ü Knowledge on fish feed ingredients was garnered. ü Knowledge on how to measure digestibility of feedstuffs consumed by fish was acquired. ü Knowledge on fish feed formulation was acquired. ü Practical on fish feed formulation was carried out. Nutrition:
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This is a process by which an organism takes in and assimilated food. It involves ingestion, digestion, absorption and transport of various nutrients throughout the body where the nutrients in food are converted to body tissue and activities. It also includes the removal of excess nutrients and other waste. Nutrients required by fish There are 6 classes of nutrient. These include: Protein: - It is required in the diet to provide indispensable (essential amino acids) and nitrogen for synthesis of dispensable (non-essential amino acids). An indispensable amino acid - (AA) is one which the animal cannot synthesize in the quantity the body needs thus must be in the diet. A dispensable AA is one that can be synthesized by the animal in the quantity that is maximal for animal. In practice, fish feeds made from plant protein sources are supplemented with lysine and methionine to make up for the deficiency. Lipids: - It contains 2.25 times as much energy as an equivalent amount of carbohydrate. It is required in the diet to: provide essential fatty acids, serve as vehicle for absorption of a fat soluble vitamins (ADEK), serve as precursors for steroid hormone, increase fish feed palatability, increase dietary energy and aids in reduction of fish meal addition to fish diet. Carbohydrate: - They serve as energy source, tissue constituent, precursors of certain metabolic activities, aid in fish feed manufacture. Tropical freshwater fish species use carbohydrate more efficiently. Efficiency of use also depends on natural feeding habit of fish 62
Vitamin: - They are required in small quantities for body growth, reproduction and health. Fish feeds during storage and preservation usually lose the vitamins incumbent in them. Fish feeds are therefore generally supplemented with vitamin premix to meet the requirement and compensate for losses. Minerals: - These are required for osmotic balance between body fluids and their environment. Among all minerals, phosphorus is most important because it is required in relatively large quantity in fish diet. Fish feed Ingredients: Feed stuffs containing 20% CP or more are considered as protein supplements while feedstuffs containing less than 20% CP are usually considered as energy supplements. Protein supplements can be further categorized as animal and plant protein supplements. The characteristics of animal protein supplements include: Name
of % crude protein
deficient in
prepared from
____
dried
ingredient Fish meal
60-80
and
ground
tissues
of
undecomposed whole fish Blood meal
80-786
Methionine
clean, flesh animal blood excluding hair, stomach belching and urine
Hydrolyzed
35
clean undecomposed feathers
poultry feathers
slaughtered poultry
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from
The characteristics of plant protein supplements include: Name
of %crude protein
deficient in
ingredient Soybean meal
Soybean cake
disadvantage
prepared from
contains 48
some
oil
antinutritional
extracted
factors √
soybean
45
solvent
oil
mechanically extracted
from
soya bean
Energy supplements include grain and grain by products, animal fat and vegetables. Grains include maize and wheat. Maize is relatively cheaper than wheat and when cooked aids binding of feedstuffs. Grain by-products include wheat offal and rice bran. These can be used to replace maize and wheat in fish feeds. However it is advised that levels of 3 – 5% of rice bran be used in fish feeds because of high level of fat and fibre. Animal fats and vegetables: - These are highly concentrated sources of energy as well as sources of essential fatty acids. Animal fats used in fish feeds include beef tallow, poultry fat, lard and fish spoil. However, tallow is not recommended for use in feeds during harmattan because it is a saturated fat. Hence, vegetable oils can be used instead.
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Digestibility This describes the fraction of nutrients or energy in the ingested feedstuff or feed that is not excreted in the faeces. Methods of determining digestibility coefficients This involves either a direct or an indirect measurement of the amount of nutrient ingested and subsequently excreted. The direct method is cumbersome and expensive to carry out. The indirect method is mostly used. The indirect method of digestibility determination involves the use of non-digestible marker such as chromic oxide (Cr2O 3) which is included in the diet at a concentration of 0.5 -1%. It is assumed that the amount of the marker in the feed and faeces remains constant throughout the experimental period and that all of the ingested marker will appear in the faeces. The digestibility of the nutrient in question can be determined by assessing the difference between the feed and faecal concentrations of the marker and nutrients or energy. The percent nutrient digestibility can be estimated by the use of the following formulae: Amount of Chromic oxide (mg) present in the sample X =
1 4
x
Y – 0.0032 0.2089
Where X = weight of chromic oxide Y = absorption (spectrometer reading) Where 0.0032 and 0.2089 are constants. To calculate the % of chromic oxide in the sample, this formula is used:
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% chromic oxide = 100 X A
where X= weight of chromic oxide A= weight of sample
% Nutrient digestibility =100 - 100 (% marker in diet x nutrient in faeces) (% market in faeces x nutrient in diet)
Feed formulation is a process of combining ingredient to provide the nutrient required by a particular organism that the diet is targeted at. Factor to consider before formulating feed included: cost of ingredient, sources of ingredient, availability of ingredient, age and species of target species, etc. Methods of Feed formulation: 1. Pearson square method 2. Algebraic method 3. Trial and error method 4. Computer based methodology For the Pearson square method as the name implies, it involves the use of a square in calculation of feed ingredients for feed formulation Algebraic methods: alphabets are used to represent feed ingredients which are then inputted and solved simultaneously. Trial and error method involves arbitrarily fixing figures to ingredients to meet the protein level required based on previous knowledge. Computer based method involves the use of computer programs in formulating feed. 66
Procedure for fish feed formulation: It was carried out using the Trial and Error method. The various ground ingredients were weighed and poured on top of each other on the floor. Mixing was done with the use of shovel and big containers. After mixing, the resulting mixture was pelleted in the feed pelleting machine. The various ingredients that were mixed include: Fish meal, Soybean meal, Groundnut cake, bone meal, vitamin premix, millet, maize, ground vitamin C tablets (Ascorbic acid).
PROBLEMS IN THE NUTRITION UNIT: ü
Lack of maintenance in the area of servicing the Soybean extruder, combined milling and grinding machine, and large grinding machine.
ü
Inadequate staff.
HOW THE PROBLEMS CAN BE SOLVED: ü The Soybean extruder and other machines should be repaired and serviced. Those that need replacement should be replaced. ü More skilled hands should be employed to enable better service rendering.
PHOTO SHOTS:
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FISH PRODUCTS DEVELOPMENT PROGRAMME It is a programme under the Fisheries technology which is a research division under the Institute. The mandate of this programme is to seek for new inventions and innovation for development, to convert food wastes into inputs for fish feeds and to go into the production of other fish products such as fish oil.
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Research breakthroughs These include: ü The Kainji Gas smoking kiln. ü The Solar tent dryer. ü The modified drum kiln etc.
ACTIVITIES CARRIED OUT: ü Familiarisation of developed technologies for fish preservation was carried out. ü Knowledge on ongoing research work was acquired. Some developed technologies for fish preservation familiarized include:
Research being carried out:
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Research on the use of algae in fish feeds instead of fish meal: It has been researched that algae is very nutritious, has all the classes of food and is even eaten among some people in the Asian countries, can supplement fish meal and prevents bacterial entry into feed. Algae is collected from a pond with plankton net, soaked for 2 weeks in methanol, and filtered, dried and ground into powder. This technology is however still being developed at hand. Research on production of fish oil: It has been researched that fishes from the marine environment have more of Omega 3 fatty acids while fishes from the freshwater environment have more of Omega 6 fatty acids. Hence, research is being carried out on production of fish oil. Fish oil can be collected from fish flesh or the visceral i.e. intestines. For extraction of oil from the visceral, the visceral is heated in a pot and oil is drained out. For extraction from the fish flesh, the fish is boiled, pound in a mortar, and the resulting liquid is extracted. The fish oil produced here however is not pure since while pounding in the mortar, oil comes out with fish water thereby making it fish liquor instead of fish oil. Machinery for this technology is however still being developed.
FISH PRESERVATION PROGRAMME This is a programme under the division Fisheries technology. This unit is into preservation of fish.
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ACTIVITIES CARRIED OUT: ü Knowledge on Post Harvest Technology was acquired ü Practical on fish preservation was carried out. Post Harvest Technology: These are all the activities that take place after the harvest of fish. Such activities include: ü Handling ü Preservation ü Processing Handling: - it is the first stage and is very important in post harvest technology. It determines the quality of the product after processing. It is an integral part of post harvest technology because it determines the quality of the product. There are two types of handling: Artisanal handling: This type of handling is usually very poor and hygiene is not ensured. Fishermen leave fish at the bottom of their canoes often in dirty water under the scorching sun while fishing and on arrival at the beach sort fish on the bare ground based on freshness. The obvious poor handling practices and high ambient temperature results in the rapid loss of freshness in fish. Infestation by flies which lay large numbers of eggs on fish further reduces the aesthetic quality of fish. It is impossible to maintain absolute hygiene during handling. Industrial handling: Here, the hygiene is of paramount importance and fish are sorted into sizes then graded. The graded fish are kept in refrigerated sea water (RSW) chilled.
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Preservation: This could be done by sun drying, solar drying, smoking, freezing, and canning. Sun drying was first practiced in Bangladesh in Asia by Dough et al. Its operation is a function of humidity, temperature and movement of air. Smoking is a traditional method of drying fish. Fuel wood is used such that when the wood is ignited, the heat dehydrates fish and the smoke imparts flavor. There are two types. Cold smoking: It is practiced in advanced countries. There is possibility of keeping all EAA’s. however, this method has a shorter shelf life on fish. Hot smoking: It is a traditional method of drying fish. Here, lysine is affected but the product has extended shelf life. Traditional smoking kilns have high consumption of fuel wood and poor quality of fish due to lack of control over the temperature as disadvantage Hence the invention of improved smoking kilns e.g. Chorkor kiln, Altona/ Watternabe smoking kiln, Ivory Coast kiln, Magbon Alade kiln, Kainji Gas smoking kiln, Improved traditional smoking kiln, and Modified Drum kiln among others. Freezing and canning however are capital intensive and are not affordable by artisanal fishermen. Types of freezers used include: cabinet freezers, fast freezing cryogenic freezers, etc. Procedure for fish preservation: Moon fish (Citharinus citharus - Falia) was used for the practical. The fish was descaled (removal of scales), cut into sizes, rinsed in clean water, brined (i.e. soaked in salt solution), left to drain, 72
and then put into the modified drum kiln to smoke for 6 hours. Another set of the same fish species was descaled, degutted by slicing the fish with knife from the dorsal part bilaterally however with care. The fish was then rinsed and salted, left to drain, and put into the solar tent dryer to dry. Hydrometer readings were taken to determine humidity since it is a function of drying. A team of panelists made up of IT students assessed the fish and commented on the differences in quality. The comments ranged from that the fish smoked in the modified drum kiln was sweeter and tastier than the one dried in the solar tent to that the fish smoked in the modified drum kiln wouldn’t be as long lasting as the one dried in the solar tent. Photo shots of the practical carried out:
PROBLEM ENCOUNTERED: ü Funds were not made available by the Institute for the practical.
HOW THE PROBLEM WAS SOLVED: ü The IT team had to contribute amongst themselves to make the practical a reality.
PHOTO SHOTS: 73
FISH QUALITY AND STORAGE PROGRAMME This is a programme under fisheries technology.
ACTIVITIES CARRIED OUT: ü Knowledge on importance of keeping quality of fish was acquired. ü Knowledge on the various methods of assessing quality of fish was garnered. Fish quality: In this part of the world, quality is not a priority but quantity. Because of poverty, quality is not ensured. Fish handlers are mostly unaware of hygiene. They trample on fish and keep fish in dirty waters and containers. Fish marketers too keep fish in dirty containers and allow flies to infest the fish. At every stage of production there should be consciousness of hygiene and quality.
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Most often, fish quality refers to the aesthetic characteristics i.e. appearance, freshness or degree of spoilage which fish has undergone. It can also be considered as the characteristics and properties of a product that influences it’s acceptability to the buyer or consumer. According to the ISO 8402, quality is the totality of features and characteristics of a product or service that bear on its ability to satisfy stated needs. In this case of fish product, it entails aspects related to gastronomic delights, purity, nutrition, safety, consistency, fairness (in labeling, weight or species) and value and product excellence. How to assess quality of fish: ü Sensory evaluation ü Microbiological analysis Non Sensory methods
ü Biochemical and chemical methods of analysis Sensory evaluation is simply the use of sense organs to evaluate the quality of fish. There are a number of quality indicators on fish that one can use sensory values to assess. Sense of sight General appearance: When fish is in a very good state of quality, i.e. is bright, shiny, has external bloom and external slime is still there. The colour of Clarias spp from the tail gets faded as quality is reduced. Eyes: when fish is fresh, the eyes are full and bulgy; the pupil is distinctly clear from the cornea. When eye of fish is sinking or sunken, the fish has lost quality. The distinctiveness of the colour of the pupil (black) if it is not there means the fish is already loosing quality. 75
Gills: The gills are bright red when fish is good. The redness begins to fade as freshness reduces till green. Once the gills are green the fish is not consumable. Lateral line: This is for detection of waves and enemies in water. It is bright when fish very fresh. It will however fade away till for some species one would not see it again. Sense of touch When fish is fresh, fish is flexible, flesh is firm and the recovery rate on depression of skin of fish is fast. Sense of taste It should be fresh when fish is fresh. Where fish has gone bad, it is bitter due to formation of alkaline groups. Sense of smell Bad fish is foul most of the time because of formation of sulphur groups. Smell of fish must be fresh it is fresh. Biochemical and chemical methods of assessment of fish quality: They are more acceptable than sensory evaluation because sensory evaluation is subject to bias by assessors. Methods:
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pH: - The pH of fish is about neutral (around 7). When it is far from 7 then something is wrong. When pH of fish is 8.9, there is formation of alkaline compounds and the fish is bad. When pH of fish is 5.3, there is production of citric acid and such fish should be rejected. Proximate analysis: This is the determination of bulk nutrient composition of a biological sample e.g. crude protein, crude fat, moisture content, ash content, crude fibre, etc. Peroxide value: This is used to measure primary oxidation in fat TBA value: This is used to measure secondary oxidation in fat. Percentage solubility test: This is used to assess quality. When fish is fresh solubility is high but when low is spoilt and vice versa. Definition of some terms TBA – Thiobarbituric acid, PUFA – Poly saturated fatty acids Factors Responsible for spoilage Bacteria spoilages i.e. microbial spoilage: This is as a result of bacteria activity Oxidative rancidity: This is spoilage as a result of oxidation of fat. In this case, PUFAs are broken down to hydroperoxides. Primary oxidation: This gives rise to hydroperoxides Secondary oxidation: This gives rise to ketones and aldehydes i.e. low molecular carboxylic acid. Microbiological analysis: 77
Micro organisms in fish and fish products are categorized into spoilages organisms (which are always present in large numbers) and pathogens (organisms of public health significance). Pathogens are not usually present in large numbers but are hazardous; therefore are the main concern o microbiological quality control. Common microbiological tests include: Standard plate count (SPC): it gives a measure of the overall degree of microbiological contamination. Escherichia coli and fecal coliform bacteria (indicator organisms): - It determines the occurrence of indicator organisms in a product since all pathogens present in a given sample cannot be identified. Staphylococcus, salmonella, clostridium and Vibrio parahaemolyticus: it measures their occurrence, confirms their presence and degree of contamination.
AQUATIC PATHOBIOLOGY PROGRAMME This programme deals with fish diseases, carries out research on diseases causal control.
ACTIVITIES CARRIED OUT: ü Knowledge on fish diseases and it’s types was acquired. ü Knowledge on abnormalities associated with vitamin, mineral, and feedstuff imbalance was carried out. Disease is anything that causes deformity, poor return, loss of appetite, loss of growth potential, loss of fecundity and increase I production cost. 78
Types of fish diseases These include: Infectious disease and non infectious disease Infectious diseases are those caused by pathogens. Noninfectious diseases are those caused by management or nutritional abnormalities. Bacterial diseases: They are microscopic organisms which are different from other cells by lacking nuclear membrane. Bacteria multiply by binary fission. They live in the dead cells of host. They are highly ubiquitous. Examples are: white spot disease caused by Flexibacteria columnaris, gill disease which is caused by mycobacterium spp, pseudomoniasis is caused by pseudomonas spp. Other diseases are fin rot, bacterial hemorrhagic septicemia, etc. Bacteria could also be primary or obligate pathogen which are not normally aquatic pathogens but are capable of causing disease in healthy individual e.g. Aeromonas selemucida. Opportunistic pathogens are normally free living organisms either in water or on the fish that are capable of adopting pathogenic role under certain circumstances e.g. Aeromonas hydrophilia, pseudomonas spp, Vibrio parahaemolyticus. Parasitic diseases: All fish are potential hosts to many different species of parasites and a small number of the parasites probably cause little harm. One thing that is common with them is that they are highly prolific and could cause diseases when they overwhelm fish. Types
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Endoparasites: They are not common in ornamental fish but are common in other fish species. They invade the internal body of fish, the tissues, intestine or stomach. Ectoparasites: They invade all the external surfaces of the fish. They invade and causes severe damage to skin and could lead to secondary bacterial typically body ulcers and bacterial fish diseases Fungal diseases: Some fungi are associated with causing abnormalities in fish. They exhibit growth of mycelia or mould like cotton on the body e.g. mucous diseases infection, Aspergiliosis, and Saprolegniasis. Viral diseases: they are ultrasonic, intracellular filter passing organisms. The only identified viral disease in Africa is lymphocytes. Other examples include: infectious pancreatic necrosis, infectious hematopoietic necrosis, spring varemia of carp, channel cat fish virus, etc. Nutritional diseases are diseases caused by deficiency or as a result of imbalance nutrition. Abnormalities associated with vitamin, mineral and feedstuff imbalance includes Vitamin A – growth retardation, edema, acytis, bulging of eye, hemorrhage of kidney, etc Vitamin K – anemia, increase in coagulation time, hemorrhages on body surface etc. Vitamin E – Edema, growth retardation, hypo pigmentation, etc. Minerals imbalance Phosphorus – bone deformation, reduced growth rate
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Iodine – goiter, swollen jaw and thyroid tumor Iron- anemia Magnesium – renal calicinosis Zinc - eye lesion Copper – reduced growth rate Calcium – skeletal deformation Stuff imbalance Lipid – loss of appetite, skin discoloration, fin erosion, fatty liver, poor growth rate etc. Protein – poor growth rate, spinal abnormalities, deformity, skin discoloration, low resistance to disease infection. Fibre – gut impaction, loss of appetite, excessive fecal output and starvation Carbohydrate = lethargy, growth retardation, enlarged liver, excessive weight loss, hyperglycemia, lipolysis, ataxia, uncoordinated swimming, shock, etc.
FISHERIES BIOLOGY PROGRAMME This programme is under the Artisanal fisheries division. The mandate of this programme is to look at the food and feeding habit of fish in Nigerian water bodies, fecundity studies and the growth rate of fish species.
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ACTIVITIES CARRIED OUT: ü Practical on determination of fecundity of fish was carried out ü Practical to determine the age of fish was carried out. ü Knowledge on determination of food and feeding habit of fish was acquired. ü Knowledge on the methods of conducting stock assessment was garnered. Procedure in determining fecundity in fish: The materials used for the practical include: preserved egg samples from Silver catfish (Chrysichthys nigrodigitatus), measuring cylinder, Petri dish, dissecting kit, distilled water etc. The preserved egg samples was poured into a Petri dish, the preservative i.e. formalin was drained off to abate the choking smell. 100 eggs was counted into another Petri dish. A water volume (initial) of 20ml was put into the measuring cylinder. The counted eggs was then poured into the measuring cylinder by picking them in one by one and preventing the eggs from sticking on the cylinder. The water displacement caused by the addition of eggs was calculated and was found to be 1ml (Water displacement = final volume – initial volume). The total egg mass was then put into the measuring cylinder and the water displacement was calculated (Water displacement = 35ml-20ml = 15ml). An equation was then set: If 100 eggs causes water displacement of 1ml X eggs will cause water displacement of 15ml i.e. 100 eggs → 1ml
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X eggs → 15ml X eggs = 100 eggs X 15ml = 1500 eggs 1ml Hence the total number of eggs is 1500. Note: The dissecting kit was used in picking the eggs and dislodging them into the measuring cylinder. It was also used to separate the eggs from the tissues. Procedure in determining age of fish: Materials used include: the scales of Tiger fish (Alestes spp), Petri dishes, detergent, cotton wool, and microscope etc. Four scales were removed and soaked in warm water to remove the tissues, washed with detergent in a Petri dish and rinsed with water in another Petri dish. The scales were wiped dry with cotton wool, placed on the slide and covered with the cover slip to be viewed under the microscope. Procedure in determining food and feeding habit of fish: This can be done by carrying out stomach content analysis and is thus: Identify the fish, collect sample fresh, determine sample size, dissect and get the stomach, preserve the stomach in a sample bottle using 5% formalin, pick the stomach into a Petri dish, use scissors to rip the stomach apart, put the contents in a Petri dish, separate and sort the macro organisms from the microorganisms, count the number of occurrence of the macro organisms seen. To check for microorganisms, put the stomach on a dish, put 1-2 drops of 83
distilled water, check the micro content and use a guide to identify microorganisms, organize result based on percentages. The percentages then show whether a fish is herbivorous, carnivorous or omnivorous. Stock assessment is done to have knowledge on when to restock. It is also done to increase the productivity of a water body. Methods of conducting stock assessment: 1. Fishermen catch: - in this case, the fish caught by fishermen is analysed. 2. Experimental approach: - in this case, experimental gear is used by fisheries scientist and the fish analysed. Sizes of Experimental gill net used include: 30x3m2, 50x3m2, etc. with mesh sizes ranging from 1 – 11/2 – 2 – 21/2 – 3 – 31/2 – 4 – 41/2 – 5 – 7 inches or fingers. When restocking water bodies to increase productivity the carnivore to forage ratio of 1:4 is ensured, fish are allowed to stabilize by establishing closed fishing season for a period of 6=7 months to allow for recruitment. Then post stocking survey is carried out.
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FISHERIES STATISTICS/GEAR PROGRAMME These are two units in one. Fisheries statistics is an aspect of fish biology that deals with collection of data on the morphological attributes of fish. Fish gear technology is a programme under the Artisanal fisheries division that deals with fishing gears.
ACTIVITIES CARRIED OUT: ü Basic knowledge on fisheries statistics was acquired. ü Familiarisation of fishing gears was carried out. ü Basic knowledge on fish gear technology was acquired 85
ü Practical on production of gill net was carried out. Fisheries statistics is an aspect of fish biology that deals with collection of data on the morphological attributes of fish. Features that aid in identification of fish: 1. Morphometric features:- this are the measurable parts e.g. standard length (SL), total length (TL) etc. the standard length is length from the tip of the snout to the caudal peduncle while total length is length from the tip of the snout to the end of the caudal fin. In taxonomy, standard length is more important because the length of the caudal fin in some fish species is too long and also because in some cases the caudal fin is eroded. 2. Meristic features: - these are the features that can be counted e.g. the number of rays in the anal, dorsal, and caudal fins, the number of scales etc. 3. Appearance and position of body structures i.e. fish species that have barbells and those that do not. 4. Chromosome numbers and genetic parameters e.g. DNA Sequences aid in identification of fish species. 5. Principal component analysis is a computer based program used to analyze data and separate fish species from each other. 6. Colour is also an identification aid but is not very a very reliable feature because fish colour is dependent on the environment. 7. Keys have been developed by authors to aid in fish identification. Familiarisation of fishing gears was carried out 86
Fishing gear is anything apart from ordinary hands that is used to remove fish from the water body. Fishing ground is where fishing activities take place e.g. rivers, reservoir, streams etc. Gears can be active or passive. Active gears are gears that can catch fish immediately e.g. cast net, trawl net, hook and line etc. while passive gears are gears that do not catch fish immediately but are set to catch fish e.g. traps, gill net etc. The mesh size of a fishing gear is the distance between two opposite knots. A mesh has a diamond shape, 4 bars and 4 knots. A bar consists of two adjacent knots. 87
Fishing gear construction: This can be done with the use of either natural netting material e.g. cotton, sisal etc. or artificial netting material e.g. PP, PVC, PE, PVD, PVA, PES etc. The accessories i.e. non-netting materials used include sinkers, ropes, cord, floaters etc. Some terms: Clove inch: - it is the distance of the tying of the meshes to the head rope. Stape column: - it is the distance between two floaters. Procedure of production of gill net: A netting material with mesh size 3” was used. The stape column was set at 2m. fisherman’s needle with twine was used to mount the net onto the head rope by putting the needle through 3 consecutive mesh holes and tying at a constant fixed distance on the head rope (Clove inch). While mounting the netting material on the head rope, the floaters were fixed at a set distance of 2m.
LIMNOLOGY PROGRAMME This is a programme under the Environmental studies division.
ACTIVITIES CARRIED OUT: ü Basic knowledge of Limnology was acquired. ü Practical to test for dissolved oxygen level in a water sample was carried out. 88
ü Practical to test for the pH value of a water sample was carried out. ü Knowledge on the production of natural fish food (Zooplankton) was acquired. Limnology is a programme under environmental studies division. Limnology is the study of the physio-chemical parameters and biological characteristics of inland water bodies. Examples of physical parameters include: color, odor, turbidity and transparency, temperature and taste, etc. Examples of chemical parameters include: dissolved oxygen, pH, ammonia, ammonium nitrate, nitrite, calcium and magnesium (These are responsible for total hardness of water) etc. The presence of heavy metal such as copper, lead, mercury, arsenic, cadmium, etc are to be checked to avoid pollution. Under limnology, there are sub programmes and they include: ü Ecology and productivity studies ü Freshwater pollution studies ü Benthic ecology ü Natural fish food production (zooplankton) Some limnological equipment: ü Vandorm water sampler is used to take water samples at various depth.. ü Ekman bottom grab is used to take bottom soil which can be used to analyze for the presence of heavy metals and also various benthic organisms.
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ü Inverted microscope: It is used to identify and count algae, zooplankton and benthic organisms ü Conductivity meter: It is used to measure conductivity meter. Conductivity is the level of mineral salts in the water. ü Spectrophotometer is used to analyze for cathions and anions in a particular water sample. Others include Dissolved oxygen meter, pH meter, and Thermometer and Secchi disc. ü Winkler’s azide modification method This is used for D.O. level determination. It was invented in 1888 and is made up of 3 reagents. Reagent 1 contains manganese chloride, Reagent 2 – potassium hydroxide + Potassium iodide, Reagent 3 – concentrated H2SO4 (sulphuric acid). Materials used for the practical include: 200ml dissolved oxygen bottle, reagents, beaker, and sodium thiosulphate. Procedure: collect sample water, put 1 ml of reagent 1, put 1 ml of reagent 2, cover the sample bottle, shake for proper for distribution, a white precipitate or brown precipitate is formed. When whitish dissolved oxygen is low, the higher the brownish colour the higher the DO level. The precipitation is equal to the DO level. Add 1ml of reagent 3, it will react with the precipitate to form a golden yellow coloured simple which is equal to the precipitate and equal to the DO level in the water sample. 10 ml of the sample is taken out of the 200ml into a beaker and then titrated with sodium thiosulphate. The sodium thiosulphate is a base used in titration to turn the color of the sample
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to neutral. The quantity of the base used until it becomes colorless is then used to calculate the DO level of that sample. In this case, it was 0.45ml. D.O. = a b
D.O.
x
titre value
= 200ml 10ml =
x
where a =initial volume of water b =quantity for titration Titre value = quantity of sodium thiosulphate used
0.45
9mg/l
Test for pH Lovibond comparator was used. Two test tubes were filled with 10ml water. Then ten drops of indicator was put into 1 of the test tubes. The indicator used was bromethymol blue (pH indicator). There are two slots for the lovibond comparator. The colored test tube i.e. the test tube containing the colored water sample was placed into the transparent slot and the test tube with only the sample water was put into a colored slot. Then the knob was turned for the colours seen through a sitting glass of the two test tubes to match. The pH value was then read. Procedure for Natural fish food production Fill in water, from either river, bore hole or tap. If tap water, dechlorinate it, and if borehole cure it to remove the hardness. Conductivity must be low. Fertilise the tank with organic manure, inoculate with zooplankton. On the 4th day, zooplankton must have come up. On the 7th to 8th day, the brown color (color associated with zooplankton) will have faded away, and the green colour will have started to emerge.
PHOTO SHOTS: 91
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POLLUTION STUDIES PROGRAMME This is a programme under the environmental studies division. This programme deals with studies on pollutants, their toxicity, remedy and impacts on aquatic life.
ACTIVITIES CARRIED OUT: 93
ü Knowledge on pollution was acquired. ü Knowledge on the factors that determine the severity of pollutants was acquired. ü Knowledge on the ways of handling slowly degradable or non degradable substances was acquired. ü Knowledge on the impacts/effects of pollution in the aquatic environment was garnered. Pollution is the introduction of unwanted substances into the environment that renders the environment unsuitable for it’s intended use or purpose. It could be defined as an effect that interferes with man’s use of his environment. Pollution studies programme is one of the programmes under Environmental studies division. Objectives of pollution studies: 1. To determine through scientific studies the presence, nature, and extent of pollution in Nigerian inland water bodies. 2. To determine or assess the impact of pollution on the biota, environmental integrity and ecology of the environment. 3. To produce appropriate design or method to abate the pollution or impacts of pollution in an environment. Factors that determine the severity of the harmful effects of pollutants: 1. The chemical factor: - i.e. the active ingredient of that pollutant determines the severity of the pollution.
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2. Concentration: - i.e. the severity is dependent on the amount per unit area or volume per unit area or weight per unit area. 3. Persistence: - i.e. how long the pollutant will stay before it is being degraded or broken down. Ways of handling slowly degradable or non degradable substances: 1. Refuse to use 2. Reduce the usage 3. Recycle i.e. the byproducts that should be wastes are taken back to industries to be re used for other products. 4. Reuse i.e. to use over and over e.g. coca-cola bottles. Impact or effects of pollution in the aquatic environment: 1. Decrease in Oxygen content which could create anaerobic environment. 2. Destruction of the biota. 3. Introduction of toxic substances which will injure th gills pr other external structures and cause death. 4. Introduction of pathogens which could be direct, run off, seepage etc. (Pathogens are those microorganisms that cause diseases to fish).
AQUATIC VEGETATION PROGRAMME
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This is a programme under the Environmental studies division. This programme is into studies on the potential use and benefits of Aquatic vegetation, its control and curtailment of it’s harmful effects.
ACTIVITIES CARRIED OUT: ü Familiarisation of Aquatic vegetation was carried out. ü Knowledge on aquatic vegetation was acquired. ü Knowledge on the various methods of control of aquatic vegetation was garnered. Some of the familiarized aquatic vegetation includes:
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Aquatic vegetation is classified into two:
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Aquatic macrophyte i.e. the ones that can be seen without the aid of a microscope e.g. duck weed, water hyacinth, water lettuce, Azolla spp, water lily etc. Aquatic microphyte i.e. the ones that can only be seen with the aid of a microscope e.g. green algae, blue green algae etc. Aquatic vegetation can also be classified based on their physiology: Emergent i.e. those that have their roots fixed to the ground. Marginal i.e. those found on the walls of the pond or enclosure. Floating i.e. those found floating on the water surface. Submerged i.e. those found partially immersed in water with their roots not anchored onto the ground and leaves above the water. Economic importance of some Aquatic plants: Water hyacinth:- it is a freshwater plant that dominates the water column by strangulating other foreign plants. It was first detected at Epe - Lagos lagoon in 1994. In 1995, it was discovered in river Niger and in mid 1995 had covered almost all the surface of Niger. A lot of disadvantages were witnessed and include: it tends to dislodge fishing gears, it is a navigation nuisance, it harbors reptiles, crocodiles and other dangerous animals, it blocks tunnels and irrigation channels to mention a few. Lemna spp is proteinous and can be used as binder for fish feeds while water hyacinth is used as substrate for collection of eggs in hatcheries. Typha spp is used for weaving mats and other products.
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Control of aquatic vegetation: There are four different methods of controlling aquatic vegetation. These include: Physical method: - this involves the use of hands, rake to pull and remove the vegetation from the water body. Chemical method: - this involves the use of chemicals, herbicides, in the control of aquatic vegetation. Mechanical method: - this involves the use of machines in controlling aquatic vegetation. A machine called Amphibian is sometimes used. Biological method: - this involves the use of natural enemies to control aquatic vegetation. Herbivorous fish species such as grass carp (Ctenopharyngodon idella) can be used as a natural enemy because of it’s feeding habit. Some species of weevil such as Nichotina buchi and Nichotina bruchi are host specific parasites that attack water hyacinth only. The larvae of these weevils also cause havoc by boring and destroying the root.
CONCLUSION The knowledge gained so far as been compensating. The training has given me a lot of knowledge on matters in my field of study. The National Institute of Freshwater Fisheries Research, New Bussa is a place where not only knowledge on their research divisions is gained but also on recent advances in Aquaculture worldwide. IT Students whose fields are in Fisheries
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and Aquaculture or related Sciences should have their industrial attachment in NIFFR, New Bussa.
GENERAL CONCLUSION This industrial training has given me the opportunity to blend theoretical knowledge acquired in the classroom with work in Industry. It has exposed me to the environment in which I will eventually work. It has enabled me to gain experience in handling equipment and machinery which are not available in school. Knowledge on carrying out manual labour has been acquired. It has enabled me to develop personal skills such as creative thinking, resourcefulness, initiative, leadership, critical thinking and Management. It has helped me in building up friendship with Very important contacts in my field. It has enabled me to bridge the gap between the knowledge acquired in school and the relevant production skills required in industry.
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