Growth performance and carcass characteristics of horro lambs castrated at different ages
2000
Solomon Abegaz | Fikru Terefe | Ulfina Galmessa | Gemeda Dhuguma
Sixty-four male lambs of less than a week of age were assigned to with 16 animals each of intact males (T1), castration in the first week using illustrators (T2), castration using burdizo's castrator at four and half months of age (T3) and at about 10 months of age (T4). The lambs were kept to 18 months of age. At the end 4 lambs from each treatment were sacrificed for carcass measurement. Live weight and cannon bone length (CBL) and condition score data were collected from live animals. Only 27 lambs survived to the end. Overall gain realized was about 44 g/day. Least square mean values showed that entire lambs had the highest weight but the difference among treatments was not significant (p0.05). Differences in CBL and condition score were also non-significant (p0.05). Birth weight had significant effect on cannon bone length at about 18 months of age. Correlation between live weight and CBL were all highly significant while correlation between condition score and CBL were non-significant (p0.05). Least square means show that there is a clear trend that castration increased dressing percentage (DP), internal fat, omental fat, fat thickness and viscera empty, and rib eye area while it decreased tail weight and gut content. However, with the exception of omental fat (p0.05), non of the differences were significant (p0.05). It appears that castration at different stages and under the feeding regiem in this study has no significant effect on growth and body condition to 18 months of age, but slight improvement in DP, internal and backfat and reduction in tail fat indicated that castration affects distribution of fat deposition in the body. Earlier age is the best time of castration, but castrating rams approaching puberty is not detrimental.
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