Supplementation of diets with omega-3 fatty acids from microalgae: Effects on sow reproductive performance and metabolic parameters

Supplementation of diets with omega-3 polyunsaturated fatty acids (PUFA) may benefit sow reproductive performance, but the efficiency of algae as a source of PUFA is still unknown. This study evaluated serum levels of metabolic markers and reproductive performance of sows supplemented with the heterotrophic microalgae Schizochytium sp. Sows (n = 596) were supplemented from the 85th day of gestation, during lactation and until the weaning-estrous interval (WEI). Microalgae were included at five levels: 0 (control); 3.5; 7.0; 14.0; and 28.0 g/d. Blood samples were collected at the 85th day of gestation, at the 10th d of lactation and at the last day prior to weaning (WEI). Serum levels of cholesterol, triglycerides, insulin-like growth factor type-1 (IGF-1) and non-esterified fatty acids (NEFA) were evaluated. At the parity concurrent with the supplementation, no effects were observed on stillborn rates (P > 0.05), sows fed 28.0 g/d farrowed heavier piglets than sows fed lower levels (P < 0.05), but the WEI for sows fed 7.0 g/d was longer than for the control (P < 0.05). Serum levels of triglycerides were decreased during gestation, only for sows supplemented with 14.0 and 28.0 g/d (P < 0.05). At the subsequent parity, there was no difference on stillborn rates and total litter size (P > 0.05). The highest tested concentration (28.0 g/d) of Schizochytium sp. was associated with reduced serum levels of triglycerides during gestation and with increased piglet birth weight, but the supplementation generally did not benefit sow reproductive performance.