Effect of docking and diet energy on carcass fat characteristics in fat-tailled baluchian sheep

Effects of docking on carcass fat characteristics were studied in fat-tailed sheep. Male lambs were randomly divided into 2 groups. One group was docked after birth using rubber rings, and the tails of the other group were left intact (control). After weaning, 20 lambs from each group were divided into 2 subgroups; one subgroup was fed with a normal energy diet (10.25 MJ/kg ME) and the other one with a high-energy diet (11.42 MJ/kg ME) for 84 days. At the end of the fattening period, 28 lambs were slaughtered for determination of warm carcass weight (WCW) and other carcass characteristics. At 24 h postmortem samples of meat, omental fat, and caudal fat were taken from chilled (4 °C) carcasses for the assessment of fatty acid (FA) composition. No significant difference (P > 0.05) was observed in WCW and omental fat between carcasses of docking and control lambs, but lambs on 2 types of energy diets showed a significant difference (P < 0.05). Under these circumstances, docked lambs produced leaner carcasses than intact lambs (P < 0.05). Diet energy had a significant effect on average daily gain and daily feed intake (P < 0.05). Results showed that the predominant FA in body fat was oleic acid and a significant difference was observed for percentage of FA composition between fat in different parts of body (P < 0.05).

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