Bovine gene polymorphisms related to fat deposition and meat tenderness

Leptin, thyroglobulin and diacylglycerol O-acyltransferase play important roles in fat metabolism. Fat deposition has an influence on meat quality and consumers' choice. The aim of this study was to determine allele and genotype frequencies of polymorphisms of the bovine genes, which encode leptin (LEP), thyroglobulin (TG) and diacylglycerol O-acyltransferase (DGAT1). A further objective was to establish the effects of these polymorphisms on meat characteristics. We genotyped 147 animals belonging to the Nelore (Bos indicus), Canchim (5/8 Bos taurus + 3/8 Bos indicus), Rubia Gallega X Nelore (1/2 Bos taurus + 1/2 Bos indicus), Brangus Three-way cross (9/16 Bos taurus + 7/16 Bos indicus) and Braunvieh Three-way cross (3/4 Bos taurus + 1/4 Bos indicus) breeds. Backfat thickness, total lipids, marbling score, ribeye area and shear force were fitted, using the General Linear Model (GLM) procedure of the SAS software. The least square means of genotypes and genetic groups were compared using Tukey's test. Allele frequencies vary among the genetic groups, depending on Bos indicus versus Bos taurus influence. The LEP polymorphism segregates in pure Bos indicus Nelore animals, which is a new finding. The T allele of TG is fixed in Nelore, and DGAT1 segregates in all groups, but the frequency of allele A is lower in Nelore animals. The results showed no association between the genotypes and traits studied, but a genetic group effect on these traits was found. So, the genetic background remains relevant for fat deposition and meat tenderness, but the gene markers developed for Bos taurus may be insufficient for Bos indicus

Pyruvate: immunonutritional effects on neutrophil intracellular amino or alpha-keto acid profiles and reactive oxygen species production

For the first time the immunonutritional role of pyruvate on neutrophils (PMN), free α-keto and amino acid profiles, important reactive oxygen species (ROS) produced [superoxide anion (O2−), hydrogen peroxide (H2O2)] as well as released myeloperoxidase (MPO) acitivity has been investigated. Exogenous pyruvate significantly increased PMN pyruvate, α-ketoglutarate, asparagine, glutamine, aspartate, glutamate, arginine, citrulline, alanine, glycine and serine in a dose as well as duration of exposure dependent manner. Moreover, increases in O2− formation, H2O2-generation and MPO acitivity in parallel with intracellular pyruvate changes have also been detected. Regarding the interesting findings presented here we believe, that pyruvate fulfils considerably the criteria for a potent immunonutritional molecule in the regulation of the PMN dynamic α-keto and amino acid pools. Moreover it also plays an important role in parallel modulation of the granulocyte-dependent innate immune regulation. Although further research is necessary to clarify pyruvate’s sole therapeutical role in critically ill patients’ immunonutrition, the first scientific successes seem to be very promising

Organic acids an anaerobic microflora for control of experimental infection of broilers by Salmonella typhimurium and S-enteritidis

The aim of this investigation was to study the effect of organic acids and/or anaerobic cecal microflora (ACM) on systemic and digestive infection of broilers by Salmonella typhimurium and S. enteritidis. ACM was used without previous bacterial identification. The treatment with ACM increased the resistance to Salmonella spp infection. Infection was more evident in caeca, followed by rectum and crop and did not interfere on body weight of broilers. Treated and control groups showed the same degree of infection at the end of the experiment. The use of ACM isolated or combined with acetic acid, reduced the colonization of the chick's digestive system by S. typhimurium and S. enteritidis. Acetic acid added to ACM did not potentiate the reduction of digestive system colonization. Except for the crop, the isolated use of acetic, propionic or formic acids did not reduce S. typhimurium and S. enteritidis, in caeca and rectum. The use of organic acids and ACM had little effect on reduction of caecum pH. The treatment with ACM reduced the quantity of S. enteritidis in the faeces. The reduction of caecum pH did not reduce the quantity of S. enteritidis in faeces. S. enteritidis was much more invasive than S. typhimurium and use of organic acids and ACM had little effect on reduction of systemic infection.49666167