Inclusion of exogenous enzymes in feedlot cattle diets: Impacts on physiology, rumen fermentation, digestibility and fatty acid profile in rumen and meat.

The objective of this study was to evaluate if the inclusion of a blend composed of exogenous enzymes (amylase, protease, cellulase, xylanase and beta glucanase) in the individual and combined form in the feedlot steers diet has benefits on the physiology, rumen fermentation, digestibility and fatty acid profile in rumen and meat. The experiment used 24 animals, divided into 4 treatments, described as: T1-CON, T2-BLEND (0.5 g mixture of enzyme), T3-AMIL (0.5 g alpha-amylase), T4-BLEND+AMIL (0.5 g enzyme blend+ 0.5 g amylase). The concentration of mineral matter was higher in the meat of cattle of T4-BLEND+AMIL. A higher proportion of monounsaturated fatty acids was observed in the T3-AMIL group when compared to the others. The percentage of polyunsaturated fatty acids was higher in the T2-BLEND and T4-BLEND+AMIL compared to the T1-CON. The combination of exogenous enzymes in the diet positively modulate nutritional biomarkers, in addition to benefits in the lipid and oxidative profile meat.

Trypanosoma vivax infection in dairy cattle: Parasitological and serological diagnosis and its relationship with the percentage of red blood cells.

Trypanosoma vivax is an emerging infectious agent in Brazil. Trypanosomosis kills cattle, especially in regions where the protozoan is unknown and herd immunity does not occur. The present study aims to report infection by T. vivax in dairy cattle from Santa Catarina, Brazil, and evaluate the effects on the percentage of red cells in the blood. Was analyzed 146 cattle blood samples with a clinical diagnosis of anaemia (pale pink mucosa: ocular and vaginal) using indirect immunofluorescence assay PCR and blood smear. 39% of the samples were positive by IFA, but none of them were positive by PCR. It was possible to verify the presence of trypomastigote forms of parasite in 3 samples of cows positive by IFA. The percentage of red cells (hematocrit) did not differ between animals with a positive serological diagnosis compared to seronegative ones. Regardless of the concentration of antibodies, hematocrit did not differ. Another piece of information that drew attention was the hematocrit of the three animals with a parasitological diagnosis. That is, these animals had a percentage of red cells of 35, 38, 39%. Among the symptomatic animals evaluated, 11 had fever and anorexia, cows that presented hematocrit between 21 and 30%. This is the first description of infection in cattle in Santa Catarina, Brazil. Anaemia is not a clinical finding in asymptomatic dairy cows but seroreactive for T. vivax.