Arginina e valina na nutrição de matrizes suínas hiperprolíficas

Abstract

Genetic advances in swine farming have brought to the market highly productive sows with large numbers of piglets born to litter, however, some points inherent to these advances have been worrisome due to their economic impact on pig production, since they are directly related to weight at birth, as the disuniformity of litters with high weight variability. As a strategy to solve these points, the objective of this study was to evaluate whether supplementation with Arginine ( L-Arg) and Valine (L-Val) in the diet of sows in the final third of gestation and during lactation has effects on the development of the gland mammary and performance of swine matrices and their respective litters. Two experiments were conducted. In the first experiment the gene expression of amino acid transporters (AA) SLC7a7 and SLC7A9; SLC27a1, SLC27a2 and SLC27a4 fatty acids, and β-casein (CSN2) and LALBA (α-lactalbumin) milk proteins. The matrices were fed with 1) diet without supplementation of AA (CON); 2) CON + L-Arg; 3) CON + L-Val; 4) CON + L-Arg + L-Val. The density, area and alveolar diameter were not influenced by suppleme ntation with L-Arg and L-Val, however, the combination of L-Arg + L-Val increased the cell proliferation in the mammary gland of sows during lactation. Supplementation with AA did not influence expression of BCATm, SLC27a2, CSN2 and LALBA genes. Gene expression of BCATc was higher in L-Arg treatment when compared to L-Val and L-Arg + L-Val treatment matrices. The SLC7a7 gene was less expressed in the treatment with L -Val when compared to the treatment CON and L-Arg. The SLC7a9 gene was less expressed in the L-Ag + L-Val treatment than in the CON and L-Arg treatments. Expression of the SLC27a1 gene was similar between treatments, except for treatment with L-Val. SLC27a4 gene expression was similar to control in L-Arg and L-Val treatments, and lower in LArg + L-Val treatment. In the second experiment, the same treatments were adopted, however the supplementation period was different, and the matrices were supplemented from the 85 days of gestation and throughout the lactation (21 days). The performance parameters of the litter, body condition of the sows, average feed intake and blood parameters were evaluated. Supplementation with L-Arg and L-Val had no effect on the reproductive, productive and blood parameters of the sows in the final third of gestation and lactation, except for the total number of piglets born, whose treatments CON and L-Val differed, but these were similar among the other treatments. It was concluded that supplementation with 1% L-Arg and 120% of L-Val: Lys in rations containing corn, soybea n meal from the 85th day of gestation and during lactation did not promote improvement in the body condition of the sows as well as on the expression of genes related to the synthesis of proteins and fats in the milk, but increased to the cellular proliferation in the mammary gland of sows during lactation.