Effect of Dietary Enrichment with Omega 3 and 6 Fatty Acids on Blood Metabolites, Hormone Concentration and Ovarian Function in Sahiwal Heifers

Abstract

Background: Supplementation of fat, especially those having unsaturated fatty acids has been proposed to carry positive effects on the reproductive organ, beside providing dietary energy to the animals. This experiment was designed to examine the effects of dietary ω-3 or ω-6 fatty acid (FA) rich oil supplementation on blood FA, metabolite and hormone concentrations; ovarian follicular growth and corpus luteum (CL) size in Sahiwal breed heifers.Methods: Eighteen heifers of 18.33±1.14 months of age and 194±4.16 kg of mean body weight were randomly assigned to 3 diets and individually fed as per ICAR (2013) diets. The diets include chopped wheat straw, green fodder and concentrate mixture containing either (i) no added PUFA rich oil but palm oil @ 3.5% (PO; n=6); (ii) 3.5% added soybean oil as ω-6 FA source (SO; n=6); or (iii) 3.5% added linseed oil as ω-3 FA source (LO; n=6).Result: SO increased (P less than 0.05) the plasma concentration of ω-6 FA while LO increased (P less than 0.05) the plasma ω-3 FA. Plasma glucose, triglyceride and non-esterified fatty acid (NEFA) concentrations was not affected due to different diets. Plasma total cholesterol and HDL-cholesterol were significantly higher (P less than 0.05) in SO and LO in comparison to PO. However, LDL-cholesterol was at par among all the treatments. Growth Hormone (GH) was not influenced due to different types of oil in heifers’ concentrate mixture. Insulin concentration increased (P less than 0.05) in LO compared to others. IGF-1 was statistically higher (P less than 0.05) in SO and LO as compared to CON, which among themselves also varied significantly. Plasma progesterone concentration at day 12 post estrous was higher (P less than 0.05) in LO. PUFA rich oil supplementation in the concentrate mixture of heifers (SO and LO) increased (P less than 0.05) the size of the ovulatory follicles as well as size of CL. It was inferred that feeding PUFA rich oil to pre-pubertal Sahiwal heifer’s results in advantageous changes in the blood metabolites, plasma hormones and ovarian functions.