Effect of various levels of standardized ileal digestible branched-chain amino acids on lactating sow and litter performance

Lactation is the most metabolically demanding period in the reproductive lifetime of a sow. It is imperative that sows are provided ample amounts of dietary essential amino acids to support the demand of the lactating mammary gland for milk protein synthesis. Leucine, isoleucine, and valine, collectively termed the branched-chain amino acids (BCAA), are dietary essential amino acids in swine. However, due to common steps in their catabolic pathway, feeding excess levels of one BCAA will increase the catabolism of all 3 amino acids, which can lead to marginal deficiencies in the BCAA not provided in excess. Therefore, the response of each BCAA may depend on the levels of the other 2 in the diet. To evaluate this hypothesis, various levels of BCAA were fed to lactating sows to investigate their impact on sow and piglet performance. Dietary BCAA levels relative to standardized ileal digestible (SID) Lys were 114% or 180% for Leu, 56% or 64% for Ile, and 64% or 120% for Val. The results of this study suggest that, at the levels of intake observed, the various levels of SID Leu, Ile, and Val did not impact lactating sow or piglet growth performance.