Published online by Cambridge University Press: 27 March 2009
A sample of twelve buffalo, nine O Friesian × ♀ Egyptian native Baladi (½ Friesian) and nine ♂ Friesian ×♀½ Friesian (¾ Friesian) bulls were individually penned and fed commercially cubed concentrates and roughages from weaning at 100 kg and slaughtered over the live-weight ranges 161–560 kg for buffaloes and 176–448 kg for cattle. Weights of gut fill (GFW), empty body (EBW), offals (TOW) and carcass were recorded. Right sides of all carcasses were jointed then dissected into muscle, fat, bone and ‘other tissues’. Analysis of covariance based on the allometric equation Y = aXb was applied to assess growth patterns (estimated from the slopes) and compositional differences (estimated from the intercepts).
The effect of genotype-group was not statistically significant on EBW at the same fasted body weight and cold carcass weight at the same EBW. However, the buffalo empty body contained (P < 0·05) more offal than the ¾ Friesian empty body and heavier TOW and lighter hot carcass than ½ Friesian empty body of the same weight.
No significant genotype-group differences were found in the slope of the regression of weight of total side muscle (TSM), total side fat (TSF), subcutaneous fat, intermuscular fat and total side bone (TSB) on dissected side weight (DSW) and ½ EBW. Comparison of adjusted means, however, showed buffaloes to have significantly more TSF and TSB but less TSM than the Friesian cross-breds. Most of the difference in TSF was due to more subcutaneous fat in the buffaloes than in the Friesian cross-breds. In all comparisons the two Friesian cross-bred groups did not significantly differ from one another.
The results indicate that Egyptian buffaloes may be earlier maturing than Friesian cross-bred cattle and buffaloes of other countries. It was also concluded that in order to produce desirable carcass of fat:muscle ratio of 1:5, Egyptian buffalo bulls should be slaughtered to produce carcasses of slightly more than 230 kg whereas ½ Friesian and ¾ Friesian bulls can be taken to heavier weights. Methods for reporting carcass compositional data are discussed.