The effect of supplementation with omega-3 and 6 fatty acids to mares during late gestation and early lactation on the transfer of passive immunity in foals

Abstract

The present study aimed to evaluate the effects of omega-3 and 6 fatty acids supplementation to mares during late gestation and early lactation on the transfer of passive immunity in foals. Seventeen mares and their respective foals were included in this study. Supplementation consisted of the addition of oil corresponding to 0.05% of the mares’ body weight. Mares received one of three supplementation protocols: (1) basal diet without the addition of oil (CON, n = 7); (2) basal diet supplemented with soybean oil (SO, n = 6); or (3) basal diet supplemented with linseed oil (LO, n = 4). The oil supplement was measured and mixed into the concentrate. Supplementation started 3 months before the expected parturition date and continued until 15 days postpartum. Foals were fed exclusively with mares’ milk. To analyze the transfer of passive immunity, immunoglobulin (Ig) concentrations in colostrum, milk and blood serum samples from foals were determined. Lymphocyte proliferation analysis of mares and foals was performed using blood samples. Concentrations of IgM and IgA in foals and colostrum of mares did not differ in supplementation groups (p > 0.05). There was a tendency for higher IgGa values ​​(p = 0.08) in C1 and C2 isotypes and IgGb (C1, p = 0.07; C2, p = 0.09) in colostrum. Foals from mares supplemented with flaxseed oil showed higher lymphocyte proliferation on day 7 after birth (p < 0.05). There were no significant effects from omega-3 and 6 supplementations in mares on the passive immunity transfer in foals.