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Articles
by
D. Norris |
Total Records (
2 ) for
D. Norris |
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D.J. Novel
,
J.W. Ng`ambi
,
D. Norris
and
C.A. Mbajiorgu
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An experiment was conducted to determine the effect of different feed restriction regimes during the starter stage (14-21 days) on productivity and carcass characteristics of male and female Ross 308 chickens. A 3 (feeding levels: ad-libitum intake, 50% ad-libitum intake and 75% ad-libitum intake) x 2 (male and female chickens) factorial arrangement in a complete randomized design was used. Feed restriction affected (p<0.05) live weight of chickens at the age of 21 days and male chickens were heavier (p<0.05) than females at the same age. Chickens on 75% ad libitum feeding attained complete compensation in live weight at 42 days of age while those on 50% ad libitum feeding did not. However, male chickens attained higher (p<0.05) live weights than female chickens at 42 days of age. It is suggested that 75% ad libitum restriction feeding during the starter stage from 14 up to 21 days of age may offer some economic advantage over ad-libitum feeding regimen, mainly by enhancing feed utilization. It may, therefore, be a useful nutritional strategy to reduce the cost of commercial starter grain based-diets. |
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D. Norris
,
N.W. Selapa
,
C.B. Banga
and
J.W. Ngambi
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Records of 3379 Charolais cattle were used to estimate (co) variance components for 20 type traits. The traits analysed in the study were back, back breadth, depth, frame, front leg, head, hind leg, hind length, hind round, hip width, hooves, pastern, pigment, rump flat, rump form, rump length, scrotum, sheath, tail placement and top line. Variance and covariance components were estimated using restricted maximum likelihood procedure with univariate and multivariate models. Heritability estimates ranged from 0.02 for hooves to 0.5 for pigment. Genetic correlations ranged from -0.78 (rump form and hooves) to 0.01 (hooves with frame and front leg). Phenotypic correlations ranging from -0.01 (sheath with back breadth and depth) to 0.84 were also observed. |
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