Search

This study aimed to determine the effect of varying inclusion levels of amaranth leaf meal on the performance, blood profiles, and gut organ characteristics of Ross 308 broiler chickens. A total of 200, day-old, Ross 308 broiler chicks were randomly allocated to five dietary treatments in a complete randomized design, with each group having four replicates with ten chicks. Amaranth leaf meal (ALM) inclusion levels used in this study were 0, 5, 10, 15, and 20%. Body weight and feed intake were measured weekly to calculate the feed conversion ratio. Gut organ weights, lengths, organ pH, and blood profiles were measured and the general linear model of statistical analysis software was used to analyze collected data. ALM had no effect ( p > 0.05) on feed intake, body weight, or the feed conversion ratio of Ross 308 broiler chickens between 1-21 and 22-42 days, respectively. Furthermore, ALM inclusion levels had no effect ( p > 0.05) on dry matter (DM) or gross energy (GE) digestibility of Ross 308 broiler chickens. Ross 308 broiler chickens, which were fed with 5% ALM inclusion levels, had higher ( p < 0.05) white blood cells, lymphocytes, and eosinophils than those fed with diets containing 0, 10, 15, and 20%. Chickens that were fed with 0 and 20% ALM inclusion levels had higher ( p < 0.05) heterophils than those fed with diets containing 5, 10, and 15%. Chickens that were fed with 15% ALM inclusion levels had higher ( p < 0.05) monocytes, eosinophils, and basophils than those fed with diets containing 0, 10, and 20%. Apart from Ile, ALM inclusion of 5 and 10% had higher ( p < 0.05) essential and nonessential amino acid digestibility in Ross 308 broiler chickens. ALM inclusion levels had no effect ( p > 0.05) on gut organ lengths or weights of Ross 308 broiler chickens aged 21 and 42 days. In conclusion, 5, 10, and 15% ALM inclusion levels can be included in broiler chicken diets as they showed favor in most of the affected parameters., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Manyelo, Sebola, Ng'ambi, Weeks and Mabelebele.)

In commercial poultry production, chickens are reared under intensive conditions, which may allow infections to spread quickly. Antibiotics are used at sub-therapeutic doses in livestock and poultry feed to prevent diseases and improve productivity. However, restrictions on the use of antibiotics at sub-therapeutic concentrations in livestock feed due to growing concerns of antimicrobial resistance (AMR), together with antibiotic residues in meat and eggs has prompted poultry researchers and feed producers to look for viable alternatives. Thus, there is increasing interest in developing natural alternatives to in-feed antibiotics to improve chicken productivity and health. Probiotics, specifically from the genus Bacillus have proven to be effective due to their spore-forming capabilities. Furthermore, their ability to withstand heat during feed processing and be stored for a long time without losing viability as well as their potential to function in the acidic medium of the chicken gut, provide them with several advantages over conventional probiotics. Several studies regarding the antimicrobial and antioxidant activities of Bacillus probiotics and their positive impact in chicken nutrition have been documented. Therefore, the present review shields light on the positive effect of Bacillus probiotics as alternatives to in-feed antibiotics on growth performance, serum chemistry, antioxidant status, intestinal histomorphology and lesion scores of disease-challenged broiler chickens and the mechanisms by which they exert their actions. It is concluded that Bacillus probiotics supplementation improve growth, health and productive indices of disease-challenged broiler chickens and can be a good alternative to in-feed antibiotics. However, more studies are required on the effect of Bacillus probiotics supplementation in broiler chickens to maximize productivity and achieve the ultimate goal of stopping the usage of antibiotics at sub-therapeutic doses in broiler chicken feed to enhance performance., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Ogbuewu, Mabelebele, Sebola and Mbajiorgu.)