The effects of supplementing EPA and DHA during late gestation on ewe metabolic profile and milk production

COLEMAN, D.N.; A E RELLING; P.A. DIETER

Congreso; 2017 Midwest ASAS ADSA meeting; 2017

Fatty acids are involved in the regulation of many physiological pathways, including those involved in gene expression andenergy metabolism. Therefore, our objective was to investigatethe impact of supplementing ewes with the omega-3 fatty acidseicosapentaenoic acid (EPA) and docosahenaenoic acid (DHA)during late gestation on ewe performance, metabolic profie ofewes, and their milk production. Eighty-four gestating ewes wereblocked by conception date into group pens with 3 animals perpen and randomly assigned to a diet enriched with monounsaturated fatty acids (MUFA using EnerG II as source) or the polyunsaturated fatty acids (PUFA, using Strata G113 as a source)EPA and DHA during the last 50 d of gestation. The dose of EPAand DHA supplemented was 18 mg per kg of metabolic bodyweight (BW0.75), with total fat supplementation on MUFA andPUFA being fed at the same percent of the diet. After lambing,ewes and lambs were placed on pasture. The ewes were weighedand body condition scored on Days 0, 30, 80, and 120 (weaning)of the experiment. Blood samples were taken on Days 0, 30, 50(lambing), 80, and 120, and plasma was analyzed for concentrations of glucose and non-esterifid fatty acids (NEFA). Milkyield and composition were measured at 30 d postpartum. Therewas no difference (P > 0.05) in body weight or body conditionscore (BCS) between treatments. No signifiant differences(P > 0.05) were observed for plasma glucose and NEFA concentrations among ewes supplemented with MUFA or PUFA.Neither milk yield nor milk protein, fat, lactose, solids, somaticcell count (SCC), milk urea nitrogen (MUN), energy correctedmilk (ECM), or net energy of lactation (NEL) were different (P >0.05) among treatments. These results suggest that supplementation of EPA and DHA during late gestation has no effect on ewemetabolic profie or milk production. Further laboratory analy-ses will determine if fatty acid composition of ewe plasma andmilk were altered by feeding EPA and DHA. Future researchshould investigate the potential effects of supplementing higherdoses of EPA and DHA on metabolism and milk production.