Early feeding and high amino acid level on performance of broilers under subclinical NE challenge

Ao et al. (2012) showed that broilers with early access to dietary additives or specific nutrients have enhanced immune system and gut development. Furthermore, early feeding provided the birds with extra resilience against necrotic enteritis (NE). Therefore, the present study examined the effect of early feeding a high amino acid density diet on performance of broilers under a sub-clinical NE challenge model. A total of 630 male Ross 308 broiler chickens were assigned to a 2 x 2 x 2 factorial design with two feeding regimes (FED vs HELD), two diets (control vs high amino acid) and two challenges (challenged vs non-challenged). Each treatment had 6 replicates of 12 birds. Starter diets, with or without an extra 10% of digestible amino acids, were fed to d 13, then grower and finisher diets fed to all birds from d 13 to 23 and d 23 to 35, respectively. Feeding regimes included birds given feed and water within 6h of hatch (FED) or those fed 48h after hatch (HELD). Birds were challenged on d 14 and 15 with 'C. perfringens' type A strain EHE-NE18 (CSIRO Animal, AU) by oral gavage and performance data collected on d 13, 23 and 35.