journal of ecology, environment & biology

8 downloads 0 Views 244KB Size Report
Oct 10, 2013 - Guinea Savannah Zone of Nigeria. Journal of Ecology Environment & Biology 2013;2(1):72-77. ECOLOGICAL DISTRIBUTION OF SNAKES ...
pubscirivista.org Journal of Ecology Environment & Biology 2013;2(1):72-77

Journal home page: http://pubscirivista.org/new1.aspx

JOURNAL OF ECOLOGY, ENVIRONMENT & BIOLOGY

ECOLOGICAL DISTRIBUTION OF SNAKES AND THE PREVALENCE OF PARASITIC INFESTATIONS AND BACTERIAL ISOLATES FROM SNAKES CAPTURED WITHIN THE GUINEA SAVANNAH ZONE OF NIGERIA A. A. Adeiza, N. S. Minka* College of Agriculture and Animal Science, Ahmadu Bello University, Mando-Kaduna, Nigeria *Corresponding author: E-mail: [email protected] Received on: 05/08/2013 Revised on: 10/10/2013 Accepted on: 13/11/2013

ABSTRACT The present study investigated the types and prevalence of parasites and bacteria isolates of snakes captured in the northern (N) and southern guinea savannah zones (SGSZ) of Nigeria during the wet season. Nine different snake species were identified among 100 snakes captured. 58% were Naja spp. and 16% Pseudohaje goldii, captured mainly in the NGSZ. Bitis arietans and Pseudohaje goldii (8% each) were common in the SGSZ. Ectoparasites were found in 29% of the snakes captured with Aponomma

Key words –

(amblyomma) latum been the most common. 34% of the snake were infested with endoparasites with

Guinea savannah,

Coccidia (42%) and Strongyloides (22%) been the most common. Haemoparasites were found in 74% of the

Parasites,

snakes, of which Haemogragerina (61%) was the most common. Different bacteria isolates were found in

Prevalence

92% of the snakes. In conclusion, Naja spp. was the most common snake

Snake

found and the snakes were

infected / infested with bacteria and parasites.

INTRODUCTION The African savannah ecosystem is tropical grassland

various

with warm temperatures all year-round and with its highest

requirements. The snakes are even exported to foreign

seasonal rainfall in the wet or raining season. The savannah is

countries for exhibition shows, zoological gardens and

characterized by grasses and small or dispersed trees that do

manufacture of leather goods. Some families also depend for

not form a closed canopy, allowing sunlight to reach the

their livelihood on exhibiting snakes and they are known as

ground. The northern and southern guinea savannah zone of

snake charmers. In some cultures snakes are worshipped and

Nigeria occupied about 40% of the area of Nigeria and is the

offered milk etc. The skins of snakes are in great demand and

most extensive vegetation belt in the country. It is a belt of

are exported in various countries. In west European countries

mixture of trees and tall grasses in the south, with shorter

the leather products of snake skins are very popular. They

grasses and less trees in the north (Fig. 1). This area produces

prepare belts, wallets, purses, combs and cigarette cases,

staples food such as yams, sorghum, millet, cassava,

tobacco pouches and cufflink heads. In addition to these

cowpeas, and corn, with rice an important crop in some

other articles prepared are sports jackets, caps, shoes, and

places

[1,2]

.

like

venom

extraction

and

other

even neckties. In Brail and Sao Pando books also bound in

Snakes are an important component of the natural ecosystem

purposes

of

the

environment

and are

commonly [3]

[1] snake skin . Some species of snake are consumed as food

and there have been flourishing snake meat markets in many

.

parts of the world. Inspite of the beneficial effect of snake it

Live snakes are in great demand and are purchased for

is still considered as a public enemy, especially in the tropical

encountered in rural and urban areas of savannah zone

Adeiza AA and Minka NS: Ecological distribution of snakes and the prevalence of parasitic infestations and bacterial isolates from snakes captured within the Guinea Savannah Zone of Nigeria

pubscirivista.org Africa due to its venomous bite. Snake bite is a significant

coincided with the time of high agricultural activity,

cause of morbidity and mortality in many parts of the world.

reinforcing the association of the agricultural season,

Data from Nigerian hospitals have shown that out of every

breeding season, and migration of snakes.

100,000 admissions, 174 are attributed to snake bite . This number does not account for

Snake sampling Snake samples were captured by professional snake

unreported incidences, and those who survive envenomation

catchers during walking surveys of the areas and the paved

will often deal with secondary effects such as necrosis or limb

roads and dirt paths located in different sites, and also from

[5] amputation .

homes, schools and dilapidated buildings. The surveys were

envenomation

[2,4]

Snake bites peak between May and August and this

conducted between May to August. The captured snakes

period coincides with heavy rainfall which marks the

were taken to parasitology and microbiology laboratory of

beginning of the raining season. At this time, the agricultural

the College of Agriculture and Animal Science, Ahmadu Bello

season begins for 60% of the Nigerian population. Crops are

University Zaria, Nigeria for analysis of ecto-, endo-, haemo-

produced by family run farms called smallholdings. Farmers

parasites and bacterial isolates.

may have no or limited access to advanced tools or machinery, and directly harvest crops in the field. This puts

Parasites collection and analyses

. Besides, snakes

Ectoparasites After processing each snake, a magnifying hand lens

may carry many diseases, which can be spread to other

(10x) was used to visually inspect the skin, particularly skin-

animals, birds and humans within the ecological zone.

folds around the eyes, mouth, and vent, for the presence of

individuals in close contact with wildlife

[2]

Several studies have reported variations in species

ectoparasites. Presence of ectoparasites was determined for

of snakes found in the ecological zones of the Sahel desert,

each individual and the percentage of infested individuals

Sudan, Guinea savannah and rain forest.

However, little

and parasite prevalence were sampled and determined

information is available on different snake species found

[6]

within the narrow belt-line between the southern and

subsequent species identification using published keys.

northern guinea savannah zone of Nigeria. The present study

.When present, live ectoparasites were collected for

investigated the types and prevalence of parasites and

Endoparasites The captured snakes were pithed, dissected and all

bacteria isolates of snakes captured within the northern and

internal organs and the general cavity were analyzed for the

southern guinea savannah zone of Nigeria during the wet

presence of any endoparasite. Parasites found in the various

season.

organs were identified, counted and preserved in Formal

MATERIALS AND METHODS Study area The experiment was performed at the Livestock

Acetic Acid (FAA) and absolute alcohol separately. Flotation and sedimentation methods were

used to identify

endoparasites eggs from fecal samples. Identification and

Farm of the College of Agriculture and Animal Science,

determination of parasites was conducted under 1000×

Ahmadu Bello University, Kaduna. Snake samples were

magnification using light microscopy to determine the

ο / ο / collected from Birnin gwari (11 40 N, 06 32 E) and Kaduna

presence and absence of fecal parasites eggs or their ova,

ο

/

ο

/

(10 30 N, 07 25 E) areas, located partly in the Southern ο / ο / Guinea Savannah and from Zaria (11 06 N, 07 43 E) and

[7] which were identified using a published key .

Funtua (11ο 32/N, 07ο 19/E) areas located solely in the

Hemoparasites Hemoparasite prevalence in snakes was assessed

Northern Guinea Savannah zone of Nigeria. The study was

using microscopy techniques. About 1ml of blood from the

conducted during the wet season from May - October. The

caudal vein of each snake was collected in heparinized

areas are characterized with agriculture activities as most of

syringe with a 25-gauge needle and a small drop of blood was

the populace are agriculturist. The season of the study

immediately used to create a blood smear. Blood smears

Adeiza AA and Minka NS: Ecological distribution of snakes and the prevalence of parasitic infestations and bacterial isolates from snakes captured within the Guinea Savannah Zone of Nigeria

pubscirivista.org were allowed to air dry at ambient temperature and were

Cultural and morphological characteristics of the resultant

fixed in absolute methanol for 10 min and then stained using

colonies were enumerated studied and recorded

a modified Giemsa method

[8]

.Stained smears were cleared

[10]

.

with xylene, allowed to air dry, and then cover-slipped and

Statistical analyses A Chi-Square test was used to find out the

sealed using Cytoseal 60 (VWR, San Francisco, CA).

significance of the different associations of parasites.

Hemoparasites were determined from each blood smear

Statistical significance was confirmed at P