Effect of dietary prebiotics supplementation on growth performance, relative carcass and organ yields, gut microbiome, and blood malondialdehyde level of broilers subjected to post-hatch feed and water restriction

A trial was conducted to investigate the effect of dietary prebiotics supplementation on growth performance, relative carcass and organ weight, gut microbiome, and blood malondialdehyde (MDA) in broiler chickens subjected to delayed feed and water access post-hatch. A total of 648 one-d-old chicks (Ross 308) were randomly divided into 6 experimental groups, each consisting of 6 replicate pens having 18 chicks in each pen. The study followed a completely randomised design with 3x2 factorial arrangement of three levels of post-hatch restriction time (0, 24, and 48 h) and basal diets with or without mannan oligosaccharide (MOS) prebiotics supplementation (0 and 0.1% for starter and grower or 0 and 0.05% for finisher). The trial lasted for 42 days. The chicks were weighed at the end of restriction periods. Body weight gain (BWG), feed intake, and feed conversion ratio (FCR) were recorded for days 1 -21, 22-42, and 1-42. Relative carcass and organ weights were recorded on day 42 after slaughter. Gut microbe populations (mesophiles, coliforms, lactobacilli, and Enterobacteriaceae spp.) were enumerated on days 6 and 15 of the experiment. Blood MDA levels were measured at the end of the restriction period on days 15 and 42. There was no interaction between prebiotics and restriction on any mentioned parameters. Prebiotics had no effect on BWG, feed intake, FCR, relative yields of carcass and organs, gut microbial populations, or blood MDA levels. BWG of broilers subjected to 48 h restriction was lower (P < 0.05) for days 1-21 compared to those subjected to 0 and 24 h. Feed and water restriction for 48 h post-hatch increased the feed intake (on days 22-42 and 1-42) and FCR (at days 1 -21, 22-42, and 1-42) in comparison with those restricted for 0 and 24 h post-hatch (P < 0.01 and P < 0.001, respectively). There was no effect of restriction on relative carcass and organ yields, and blood MDA. On day 6 of the experiment the count of mesophiles was higher in broilers restricted for 48 h (P < 0.001) and coliforms and Enterobacteriaceae spp. counts were higher in broilers subjected to 24 h restriction compared to 0 or 48 h (P < 0.01 and P < 0.001, respectively). In conclusion, the use of prebiotics in broilers with post-hatch feed and water restriction did not influence growth performance, relative carcass and organ weight, gut microbe populations, and blood MDA level. However, post-hatch feed restriction for 48 h may negatively affect growth performance.