Necrotic enteritis (NE) caused by Clostridium perfringens (CP) is a devasting bacterial disease responsible for economic losses, by increasing mortality because of damage to the broiler small intestine. Since ban of antibiotics use as growth promoters (AGPs) in some markets like in Europe and no antibiotic ever programs (NAE) in U.S., economic losses have become more prevalent. To prevent NE, supplementing probiotics and prebiotics in feed has been considered as an alternative to AGPs and seems to improve both bird health status and animal welfare.
The present study assessed the effect of four products administered in the feed (prebiotic product A: 250g/t, and 3 probiotic products: B, C and D at 5, 6.2 and 5.5 log CFU/g of feed, respectively) for reducing the effects of CP in a moderate NE challenge.
Three-thousand day-of-hatch chicks were assigned to six groups: (i) two control groups, negative control without NE challenge (NCtrl) and positive control (PCtrl) with NE challenge; (ii) four treated groups (A, B, C, D) with ten-replicate pens per group and 50 birds per pen.
The trial lasted 42 days, and NE was induced by adding CP to the water at dose 1x108 CFU/ml on d 18 and 19.
After the NE challenge, at d 21, no significant difference in small intestine lesion scores was recorded. On d 35, treated groups had lower FCR and heavier body weight than both NCtrl and PCtrl (10% and 16% on average respectively). At d 42, group B had the lowest mortality adjusted FCR (1.72) compared to D (1.76). Animals from groups A, B, C, D had higher body weight compared to PCtrl, showing that all products were successful in alleviating subclinical effects of CP.
Although probiotic B was used at the lowest concentration in feed it outperformed the other probiotic products by significantly reducing mortality: 8.2% versus 11.4% and 9.6% for product C and product D, respectively.
Key Words: Necrotic enteritis, probiotic, Clostridium perfringens, broilers performance