Uso de biocolina (Fosfatidilcolina) e adsorvente de micotoxinas na dieta de bovinos

Abstract

This study consists of two experiments. The first experiment aimed to evaluate the effect of phosphatidylcholine administration in the rumen or abomasum on the digestibility of dry matter and nutrients, as well as ruminal and blood parameters of cattle. Five Jersey castrated male animals with an average body weight of 829.6 ± 34.6 kg, fitted with a ruminal cannula and distributed in a 5x5 Latin square, were used. Five treatments were evaluated, one without the addition of phosphatidylcholine (control) and the others consisting of combinations of doses of 3 or 6 g/100 kg of body weight of phosphatidylcholine with the site of administration, either the rumen or the abomasum. The intake and total digestibility of dry matter and nutrients were evaluated. In ruminal fluid, pH and N-NH3 were evaluated, and the concentrations of glucose, triglycerides, and cholesterol in the blood. There was no difference in dry matter and nutrient intake between treatments. No significant differences were observed in digestibility. There were no differences in ruminal parameters, pH and N-NH3. Plasma glucose concentration was higher when phosphatidylcholine was administered into the rumen compared with administration into the abomasum, while cholesterol concentration was lower. The second experiment aimed to evaluate the effect of mycotoxin adsorbent use on endotoxin control in cattle fed a high-starch diet. Four Jersey cattle (806 ± 45 kg) with ruminal cannulas were used in a 4 x 4 Latin square design. The treatments consisted of four adsorbent inclusion levels: 0 g/kg BW (control); 20 mg/kg body weight (BW); 40 mg/kg BW and 80 mg/kg BW. Each experimental period lasted 21 days, of which, in the first seventeen days, the steers were fed a maintenance diet consisting of a roughage:concentrate (R:C) ratio of 80:20 on a dry basis without the adsorbent. From the 18th to the 21st day, the animals received the adsorbent and a challenge diet with a R:C ratio of 30:70. Blood, ruminal fluid, and feces were collected for lipopolysaccharide (LPS) evaluation. The dietary change resulting in acidosis caused an increase in the endotoxin concentration in all samples evaluated. The use of the adsorbent showed a tendency to reduce the endotoxin concentration in ruminal fluid samples; however, it did not change the endotoxin concentration in plasma or feces.