Quitosana em suplementos para bovinos em pastejo

Abstract

The objective was to evaluate the addition of chitosan as modular fermentation in supplements for grazing cattle. five (5) cannulated crossbred steers rumen with an average weight of 350 kg on individual paddocks Urochloa brizantha and distributed in Latin 5X5.Os square animals were supplemented daily at the rate of 0.15% body weight (BW) were used. Chitosan (85% desatilação) was provided in combination with a proteinaceous mineral supplement 30% (43,5% corn, 4% soybean meal, 8.5% urea, 44% mineral) second balanced NRC (2000) . The chitosan doses used were 0, 400, 800, 1200 and 1600mg of chitosan per kg DM. The total forage availability was held on the first day of each experiment period. Voluntary intake of dry matter was determined by the ratio between the amount of excreted faecal dry matter and the use of internal display (ADFi). The collection of rumen fluid to determine the pH and ammonia (NH3) rumen was carried directly into the rumen at times 0, 2, 4, 6 and 8 hours after delivery of the supplement via rumen cannula. The addition of chitosan in supplements provided quadratic effect on the total dry matter intake of the animal, urea excretion rate and microbial protein synthesis (P <0.05). There was no effect of the inclusion of chitosan on rumen pH of animals (P> 0.05), obtaining average between treatments of 6.5, but there was a quadratic effect (P <0.05) for N-NH 3 concentrations, where the level of great inclusion was 875 mg / kg DM. The inclusion of chitosan provided an increase in digestibility of the protein in DM and growth of animals, which estraria according to NNH3 contents. Chitosan can be added to supplements for animals to pasture 900mg / kg DM.