EEect of strategic feed supplementation during ...

5 downloads 0 Views 762KB Size Report
metabolism trial (after 135 DPM) was significantly lower in treatment HL in comparison to comparable values of HH and LH ... of each animal were preserved in 1:4 sulphuric acid (v/vf .... Mellor and Matheson (1 979) has reported that abruptly.
Indian Journal of Animal Sciences 78 ( 1 ) : 97-101, January 2008

EEect of strategic feed supplementation during pregnancy on the performance of goats ANKUR RASTOGI1, NARAYAN DUTTAZand K SHARMA3

Indian Veterinary Research Institute, Izafnagal; Uttar Pradesh 243 122 India Received: 3 January 2007; Accepted: 22 June 2007

ABSTRACT Gravid does (18) were randomly divided into 3 groups, fed wheat straw ad lib. and supplemented with concentrate mixture @ 20gkgW0.75throughout the experimental period to study the effect of strategically supplemented pregnancy was given as pregnancy allowance on the reproductive performance of goats. Additional 20g concentrate mixt~re/lcgW~.~~ allowance to gravid does from 61 days post-mating (DPM) to term, 61-90 DPM and 121 DPM to tenn to HH (highhigh), HL (high-low) and LH (low-high) group, respectively. Mean daily dry-matter (DM) intake (gkg W 0 9 increased significantly during first 90 days of gestation and then became stable. Intake and digestibility of DM by does during metabolism trial (after 135 DPM) was significantly lower in treatment HL in comparison to comparable values of HH and LH treatments, whereas crude protein digestibility was significantly higher for treatment LH followed by HH and HL, respectively. Live weight changes, foetal growth and reproductive performance of goats on treatment HH and LH were statistically similar and significantly better relative to does on HL. Results indicated that last month of gestation is the period of most rapid foetal growth necessitating supplementation of pregnancy allowance to economize production and minimize reproductive losses in goats.

Key words: Foetal growth, Gravid does, Pregnancy allowance, Strategic supplementation

In mid pregnancy, the nutrient requirements of foetus are still low, but placenta must grow at this time and if growth of placental tissue is restricted by low plane of nutrition, it will be unable to adequately nourish the foetus in final stage of pregnancy and consequently birth weight will be compromised (Osuagwuh et al. 1980, Rafiq et al. 2003). Rapid rate of foetal growth during the final 6 weeks of pregnancy imposes a metabolic challenge to the doe, which is met by the mobilization of maternal body tissue (Osuagwuh and Aire 1990) and this may result in weight loss of doe, if the dietary supply of nutrients is inadequate (Sibanda et al. 1997, Hossain et al. 2003, Rafiq et al. 2003, Martin et al. 2005). An unscientific approach to animal feeding during pregnancy may lead to reproductive wastage resulting from either abortion or neonatal death due to low birth weight resulting from malnutrition of pregnant does (Osuagwuh and Akpokdje 1981, 1986, Patra et al. 2006) or dystocia due to absolute foetal oversize as a result of high plane of nutrition Present address: 'Assistant Professor, Department of Animal Nutrition, Faculty of Veterinary Science and Animal Husbandry, Sher-e-KashrnirUniversity of Agricultural Science and Technology, R S Pura, Jammu 181102. 2Senior Scientist, 3Director, Centre for Advanced Studies in Animal Nutrition.

level. Therefore, the present study aimed to investigate the effect of strategically supplemented pregnancy allowance on the nutrient utilization and reproductive performance of stallfed goats.

MATERLALS AND METHODS Experimental animal Local non-descript adult does (21), of about 36-months of age, weighing 16.2650.82 kg, were teased twice daily for oestrus detection and were bred by a single buck during standing oestrus. Does returning to heat again in the subsequent cycle were re-bred. Eighteen c o d m e d pregnant goats [confirmation by ultrasound technique at 60 days post mating (DPM)] were randomly allotted to 3 dietary treatments of 6 each comprised HH (high-high), HL (highlow) and LH (low-high) in a completely randomized block design. Does were penned individually in well ventilated sheds and allowed daily out-door exercise in an adjacent dry paddock between 0830 to 0930 h. Experimental procedure All the does were offered a basal diet of wheat straw ad lib. supplemented with concentrate mixture (wheat bran, 55%; maize 20%, soybean meal 22%, mineral mixture 2%,

[Indiun Jo~irnriloJ'Anirnu1Sciences 78 (1)

RASTOGB ET AE.

98

salt 1% and 250 g of vitamin mixture was added to each batch of 100 kg concentrate mixture to take care of dLuly vitamin A requirement of animals) @ 20g/kgW07s thoughout the experiment. Additional supplementation of 20g concentrate m i x t ~ r e / k g W ~as' ~pregnancy allowance was given from 61 DPM to term, 61-90 DPM and 121 DPM to term to HH, HL and LH group, respectively.. Daily aPlowance of the concentrate was offered in single meals in the morning followed by wheat straw for ad lib. intake after ensuring complete consumption of concentrale. A metabolism trial of 7 days was conducted after 135 DPM during which the gravid does were housed in individual metabolism cages. Samples of feed offered and refused were collected daily and oven dried at 85 (3 2OC for dry-matter (DM) estimation. Dried samples were pooled, ground and stored for further analysis. Similarly, totd daily (24 la) faecal output was recorded and a sub-sample (20%) collected and dried in hot air oven to a constant weight for DM estimation. Representative samples of daily faecal and urine collection of each animal were preserved in 1:4 sulphuric acid (v/vf and pooled for 7 days for nitrogen estimation. Other subsamples were retained for further chemical analysis.

Live weight changes arzd pregnancy variables Does were weighed at mating, at fortnightly intervals during gestation period and within 24 h of kidding. Body weight (BW) of kids was also recorded within 24 h of birth. The does were weighed only after expulsion of placenta. Pregnancy variables (products of pregnancy, foetal growth rate and average daily weight gain of does) were derived from the live weight changes of gravid does based on the assumptions that BW of gravid does during gestation indicate foetal prenatal development and secondly, pregnant goats grew at a constant rate during gestation (Amoah et al. 1996, Akingbade et al. 2001). Chemical and statistical analysis Representative sub-samples of feeds offered and refused and faeces were analyzed for proximate composition (AOAC 1995) and fibre fractions (Van Soest et aE. 1991). Urine samples were analyzed for N (AOAC 1995). Results obtained were subjected to analysis of variance and treatment means were ranked using Duncan's multiple range test (Duncan 1955). Body weight of pregnant does at mating and pregnancy variables were subjected to regression analysis by programming and processing in a personal computer. RESULTS AND DISCUSSION

Intake and nutrient utilization Chemical composition of the concentrate supplement and wheat straw is given in Table 1. The values of concentrate mixture and wheat straw observed were within the normal range (Osuagwuh and Aire 1990, Osuagwuh 1992, Waque et al. 2004, Girdher et al. 2006). Mean daily dry matter intake

JC-Z

Table 1. Chenmical composition of feeds (% DM) Attributes

Concentrate mixture

Wheat straw

Organic matter Crude protein Ether extract Total ash

Crude fibre Neutral detergent fibre Acid detergent fibre

--

-93.4-1. 0.2 3.12 0.1 I .I+0.3 6.65 0.2 39.72 0.4 83.827 1.1 57.5rt 0.4 - -- - --

(DMII; g/kgWo75)of gravid does during gestation is given in Table 2. hespeclive of the stage of pregnancy or treatment, straw intake (g/kgWo7') of gravid does decreased with the increased dietary level of concentrate. The mean total DM1 (g/kgW075)of does was sirnilar (Pc0.05) irrespective of dietary treatments. Mean wheat straw intake of does an treatment HL and LH was significa~~ely (P