Original research articleFeeding microalgae increases omega 3 fatty acids of fat deposits and muscles in light lambs

•Dietary DHA-rich microalgae modified fatty acid composition of lamb fat deposits.•Intramuscular fat was more affected than subcutaneous or internal fats.•Feeding DHA-rich microalgae improved fatty acid profile of intramuscular fat.•The M. Infraspinatus deposited more DHA and n3 than M. Longissimus..

In the present study, we investigated the effect of dietary supplementation with microalgae rich in DHA (C22:6n3) on the fatty acid composition of different fat deposits and muscles in light lambs. Two dietary treatments were studied: control (CT) and microalgae (MT), containing 2% of DHA- rich microalgae. Dietary incorporation of microalgae modified fatty acid composition in all anatomical locations studied (intramuscular, subcutaneous and kidney knob and channel fat); however, intramuscular fat was the most affected deposit. Intramuscular fat of MT lambs had higher levels of DHA (3.35%) and total n3 fatty acids (5.71%), than that of CT lambs (0.25 and 1.23% respectively). Dietary supplementation with microalgae produced a greater proportion of DHA and total n3 in M. Infraspinatus (IM) (5.12 and 8.13% respectively) compared with M. Longissimus (LM) (3.35 and 5.71% respectively) and M. Psoas major (PM) (3.62 and 6.24% respectively). Dietary supplementation with microalgae enhanced the nutritional quality of lamb muscle with more favourable PUFA/SFA and n6/n3 ratios in conjunction with increased levels of DHA and total n3 fatty acids.