AUTHOR=Pewan Shedrach Benjamin , Otto John Roger , Kinobe Robert Tumwesigye , Adegboye Oyelola Abdulwasiu , Malau-Aduli Aduli Enoch Othniel 

TITLE=Fortification of diets with omega-3 long-chain polyunsaturated fatty acids enhances feedlot performance, intramuscular fat content, fat melting point, and carcass characteristics of Tattykeel Australian White MARGRA lambs

JOURNAL=Frontiers in Veterinary Science

VOLUME=9

YEAR=2022

URL=https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2022.933038

DOI=10.3389/fvets.2022.933038

ISSN=2297-1769

ABSTRACT=<p>Meat eating quality indices such as intramuscular fat content (IMF) and fat melting point (FMP) of the <italic>Longissimus thoracis et lumborum</italic> muscle and the feedlot performance, carcass traits, and commercial wholesale cuts of lot-fed Tattykeel Australian White (TAW) MARGRA lambs as a result of dietary fortification of the diet with omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA) were evaluated. A total of 75 TAW MARGRA lambs at 6 months of age with an average liveweight of 30 ± 1.2 kg were used. The lambs were randomly allocated to the following three dietary treatments of 25 lambs each in a 47-day feeding trial using a completely randomized experimental design: (1) control diet of hay plus pellets without omega-3 oil, (2) hay plus commercial whole grain pellets (MSM) without omega-3 oil, and (3) hay plus pellets fortified with omega-3 oil. It was hypothesized that dietary supplementation with omega-3 fortified pellets will improve feedlot performance, meat-eating quality indices of IMF, FMP, and carcass characteristics. Lot-fed lambs on the MSM whole grain had the highest feed intake of 1.69 kg/day, followed by the control at 1.57 kg/day and the lowest in the omega-3 diet at 1.01 kg/day (<italic>p</italic> = 0.0001). However, the omega-3 diet had the highest average daily gain of 230 g/head/day (<italic>p</italic> = 0.0001), indicating the greatest feed efficiency since it had the best growth response with minimal feed intake. Post-slaughter evaluation of the <italic>Longissimus thoracis et lumborum</italic> muscle revealed significant treatment variations in IMF (<italic>p</italic> = 0.0001), FMP (<italic>p</italic> = 0.0001), pH (<italic>p</italic> = 0.0380), and wholesale French rack primal cut (<italic>p</italic> = 0.0001). Strong correlations (<italic>p</italic> &lt; 0.05) between liveweight, temperature, pH, FMP, and IMF were observed. Similarly, significant correlations between carcass characteristics of total saleable meat yield, lean trim, fat trims, bones, and leg shank were evident (<italic>p</italic> &lt; 0.05). However, there were no treatment differences in the final liveweight, GR fat depth, hot standard carcass weight, or dressing percentage. The findings indicate that feedlot performance, meat-eating quality traits such as IMF and FMP, and commercial wholesale French rack cuts can be further improved during feedlot finishing of TAW MARGRA lambs through dietary supplementation with omega-3 oils, and hence the tested hypothesis of improved meat quality attributes is partially confirmed.</p>