Growth Performance and Biometry of Nellore Brown Lambs from Birth to Weaning under Different Systems of Rearing

Background: Among the three varieties of Nellore sheep, Nellore brown was most popular among the shepherds of Telangana state. The research on the performance of the other two varieties i.e. Palla and Dora was done extensively in their home tract but less data was available about performance of Nellore brown under different system of rearing. The growth rate of lambs was highest from birth to weaning in their life. The system of rearing can influence both growth rate and biometrical measurements of the lamb. The performance of the lambs during this stage influence the productive and reproductive performance in the lifetime.Methods: Sixty Nellore brown ewes (1.5-2 years) were selected from Sheep unit, Livestock Research Station, Mamnoor, Telangana for the present study. The lambs born in intensive (G1, lambs born N=14), Semi-intensive (G2, lambs born N=14) and Extensive (G3, lambs born N=12) system of rearing were used to study the growth performance and biometry of lambs from birth to weaning.Result: The birth weight (kg) of lambs in G1 and G2 groups were significantly (P<0.01) higher than lambs in G3 group. The weaning body weight (Kg) was significantly higher (P<0.01) in G1 group as compared to weaning body weights in G2 and G3 group. The mean average ADG (gm) of lambs from birth to weaning was significantly (P<0.01) higher in G1 (105.4 +/- 0.19) followed by G2 (97.9 +/- 0.14) and G3 (92.8 +/- 0.07) group. The mean pin shoulder length (cm) of lambs at birth in G1 group was higher than G2 and G3 group but had a significant (P<0.05) difference with the only G3 group. In G1 group, the mean heart girth (cm) of lambs from15th day to weaning was significantly (P<0.01) higher than G2 and G3 groups. The mean gain in paunch girth from birth to weaning in lambs of three groups was nearly 19 cm and had no significant (P<0.05) difference between groups.