Postweaning Swine Performance and Serum Profile Responses to Supplemental Medium-Chain Free Fatty Acids and Tallow

Abstract

An experiment involving a total of 164 pigs weaned at 21 d of age was conducted to evaluate the dietary effects of esterified long-chain fatty acids and nonesterified medium-chain fatty acid lipid sources on postweaning growth and feed intake responses. Serum urea, triglyceride and free fatty acid profiles were measured weekly over a 28-d postweaning period. Treatment diets contained an 8% medium-chain free fatty acid (60% C 8:0, 40% C 10:0) mixture (FFA), 8% tallow or a FFA:tallow combination (each at 4%). Feeding of the basal diet and those containing FFA or the FFA:tallow combination resulted in similar postweaning pig gains during the initial 21-d period, whereas slightly lower gains resulted when tallow was provided. During wk 4, pigs fed the lipid-containing diets had higher weight gains than did pigs fed the basal diet, but for the overall 4-wk period gains were similar between all treatment groups. Feed-to-gain ratio for the 28-d period was poorer for the tallow than for the FFA diet, whereas the FFA:tallow diet combination had intermediate values; all were superior to the basal diet. Serum urea was lower in pigs fed the medium-chain FFA mixture, suggesting that energy and subsequent amino acid utilization were improved. Serum free fatty acid concentrations of C 8:0 and C 10:0 were higher (P < .01) when pigs were fed the medium-chain FFA diet than those fed either the basal or tallow diets. Serum triglyceride concentrations were higher at each postweaning measurement period when the FFA diet was fed compared with the basal treatment but lower than when pigs were fed supplemental tallow. No synergism between tallow and FFA supplements was detected.