Aiming to study the effects of probiotics on performance of broiler chickens fed on diets containing bone and meat meal with different levels of bacterial contamination, an experiment was carried out in the Federal University of Lavras . 576 one-day-old broiler chicken of the Hubbard line, of both sexes, were used. The experimental design was completely randomized, in a 4 X 3 scheme (4 rations and 3 probiotics) with 4 replications, being 12 birds per plot, housed in cages. The treatments were made up of 4 rations, one with no meat meal and with bicalcic phosphate (check) and the other three with meat meal with high, medium and lower levels of contamination (1.0x104, 4.5x103 and 1.0x103 ufc/g), respectively. Each of these rations were fed: without probiotic; with a probiotic containing about 3 billion viable cells pergram of Lactobacillus acidophilus, Streptococcus faecium e Sacharomices cerevisae, at the a dose of 10 g/ton; and a probiotic containing Enterococcus faecium, Lactobacillus acidófillus, Lactobacillus plantarum e Lactobacillus sp., at the concentration of 3 X1010 ufc/g of this product, added to water (1.33 g/L) in the first 24 hours of chick's life. It was found that there was not any significant effects (P<0.05) on the weight gain, feed intake and feed conversion, for the birds fed on the ration with low level contamination. The inclusion of bone and meat meal resulted in a better feed conversion for the birds fed on the rations with high and medium contamination. It was observed a reduction on the appearance of diarrhea, during the first week chick's life, when the probiotics were used and an increase when bone and meat meal with medium and high level of contamination.
probiotics; meat and bone meal; contamination; broiler
