The hypothesis that adding omega-3 oil to feedlot pellets will improve the meat's favourable n-3 PUFA composition was tested in this experiment. Therefore, we evaluated the productive traits and modification of the composition of n-3 PUFA of Longissimus lumborum (LL) muscle in growing lambs supplemented with microencapsulated omega-3 oil (MEOIL) in pelleted total mixed rations (TMR). Thirty six one month old Valle del Belice male lambs (14.04 ± 0.1 kg) were randomly distributed to one of the three dietary treatments (n = 12 lambs each) and provided the supplemented diets up to 14 weeks of age: 1. control (CON) pelleted TMR without omega-3 oil supplementation; 2. omega-3 oil fortified pelleted TMR at 1% (MEOIL1) supplementation; and 3- Omega-3 oil fortified pelleted TMR at 3% (MEOIL3) supplementation. Supplementing MEOIL at both levels in diet positively impacted (p < 0.05) body weight (BW) and feed efficiency. At the end of feeding period, most carcass quality traits did not vary significantly (p > 0.05) among groups, with the exception of carcass dressing and loin yield at both levels of MEOIL. The color and physical traits of LL muscle were affected by MEOIL supplementation (p < 0.05), with no significant change in chemical characteristics. Fatty acids composition of meat in term of linolenic, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were significantly (p < 0.05) influenced by both levels of MEOIL. It was concluded that the tested microencapsulated omega-3 oil preparation may be included at 1% in lamb diet for increasing unsaturated fatty acids in meat without any detrimental effects on lamb productivity.
Keywords: feeding; growth; lamb; meat; microencapsulated fish oil.