Location: Livestock Behavior ResearchTitle: Effects of a synbiotic supplement on cecal microbial ecology, antioxidant status, and immune response of broiler chickens reared under heat stress
|MOHAMMED, A - Assiut University|
|JIANG, S - Southwest University|
|JACOBS, J - Purdue University|
|Cheng, Heng Wei|
Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/10/2019
Publication Date: 12/11/2019
Citation: Mohammed, A.A., Jiang, S., Jacobs, J.A., Cheng, H. 2019. Effects of a synbiotic supplement on cecal microbial ecology, antioxidant status, and immune response of broiler chickens reared under heat stress. Poultry Science. https://doi.org/10.3382/ps/pez246.
Interpretive Summary: Dietary supplementation of probiotics has become an important management strategy in improving farm animal health and production. The current results indicated that the heat stress-induced gut microbial dysbiosis, oxidative damage and stress reaction in broiler chickens could be reduced by feeding a synbiotic (a combination of prebiotics and probiotics). Compared to controls, synbiotic fed broiler chickens had higher levels of beneficial gut bacteria and antioxidants with lower stress responses. These results could be used by producers and scientists for further investigating the mechanisms of synbiotics to prevent heat stress-associated damage in farm animals.
Technical Abstract: The aim of this study was to examine the effects of a dietary synbiotic supplement on the cecal microflora, antioxidant status, and immune response of broiler chickens under heat stress (HS). Three hundred and sixty 1-d-old male Ross 708 broiler chicks were randomly distributed among three dietary treatments containing a synbiotic (PoultryStar) at 0 (control), 0.5 (0.5X), and 1.0 (1.0X) g/kg. Each treatment contained eight replicates of 15-birds each housed in floor pens. Heat stimulation was arranged at 32 °C for 9 h daily from d 15 to 42. The results showed that, compared to controls, synbiotic fed broilers had higher levels of cecal enumeration of Bifidobacteria spp. and Lactobacilli spp., glutathione peroxidase (GPX) and plasma nuclear factor erythroid 2-related factor 2 (Nrf-2) (P < 0.05) but lower cecal enumeration of Escherichia coli and Coliforms, and heterophil/lymphocyte (H/L) ratio (P < 0.05). However, there were no treatment effects on the levels of Enterococcus spp., the circulating monocytes, eosinophils, and basophils, Toll like receptor-4 (TLR-4), Interleukin-6 (IL-6), Interlukin-10 (IL-10), and their mRNA expression, as well as plasma Kelch like-ECH-associated protein 1 (Keap-1) (P > 0.05). There were dose-related differences of the synbiotic effects; namely, the 1.0X broilers had the highest levels of lymphocytes, GPX, Nrf-2, Lactobacilli spp. and Bifidobacterium spp., while the lowest levels of heterophil and H/L ratio. The results suggest that the synbiotic inhibits the negative effects of HS on chicken health through the reduction of cecal pathogens, regulation of stress reactions, and improvement of antioxidant status. Feeding a diet supplemented with synbiotics could be a useful method for the poultry industry to improve chicken health and welfare during hot seasons, especially in the tropical and subtropical areas.