The effect of the probiotic strain Enterococcus faecium DSM 7134 in combination with natural humic substances on performance and health of broiler chickens.

The present study investigated the effect of the probiotic strain Enterococcus faecium DSM 7134 (2 x 10(7) cfu per g of feed) (probiotic group), natural humic substances (7g x kg(-1) feed) (HS group), and the combination of both (probiotic + HS group) on the performance, serum biochemistry, and biological activity of leucocytes of broiler chickens. Average body weight of chickens in different phases as well as throughout the observation period under different treatments did not differ significantly. Final body weight and feed conversion ratio (FCR) reached in 41 days of trial were 2542.