Breed effects on muscle fatty acid composition in fat-tailed sheep

Lamb meat is a traditional source of protein in Iran and the consumption levels are high compared with beef and goat meat. Production comprises proportionately about 40% of the total meat production, which is about 254 million kg per year. There are considerable differences among sheep breeds in the meat content of saturated fatty acids (SFA), monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acids and in PUFA:SFA ratios. This study was conducted to evaluate the growth performance, carcass characteristics and fatty acid (FA) composition of two fat-tailed Iranian lamb breeds, namely the Sanjabi and Mehraban. Twelve male lambs from each breed, Sanjabi (S) (n = 6) and Mehraban (M) (n = 6). weighing 23.33± 0.48 and 26.10± 2.14 kg (mean initial body weight ± standard error), respectively, were used in this experiment. Lambs were born under similar conditions following an oestrus synchronization program, kept exactly under the same conditions during their suckling, weaning and fattening periods. At the end of the fattening period (104 days), carcass characteristics and the fatty acid (FA) composition of muscle were determined. The results showed no significant differences in the average daily feed consumption (g) of Sanjabi (1192.57 g/day) and Mehraban (1338.77 g/day). Body weights at slaughter and feed conversion ratios were also similar in the two breeds. The MUFA (40.07 vs. 44.40%) and oleic acid (38.96–34.94%) contents in Sanjabi lambs were significantly (p<0.05) higher than in the Mehraban. The total SFA was significantly (p<0.05) higher in the Mehraban lambs than in the Sanjabi lambs. The muscle of the Mehraban had higher arachidonic acid content than the Sanjabi lambs. Overall, these results showed that the muscle fatty acids in the Sanjabi lambs were healthier for human consumption due to lesser saturated fatty acid levels.