Prophylactic influences of prebiotics on gut microbiome and immune response of heat-stressed broiler chickens

Abstract

Climatic changes and elevated ambient temperature are significant environmental stressors with a negative impact on birds’ physiological, immunological, and behavioral status, increasing their susceptibility to stressors and immunosuppression and consequently increasing intestinal permeability (leaky gut). Prebiotics have been utilized to stop or diminish the harmful effects of stress in chickens. We aimed to evaluate the role of mannan-oligosaccharides, and beta-d-glucan prebiotics supplements in drinking water against experimentally induced heat stress (HS) on broiler chickens and study their impact on birds’ performance, gut microbiome, and immune response. A total of 120 1-day-old Ross broiler chicks were allocated into four groups (30 birds/group), and each group was subdivided into triplicates (10 birds each). The experimental groups were classified as follows; the 1st (G1) control birds, the 2nd (G2) birds exposed experimentally to HS, the 3rd (G3) birds administered prebiotics in drinking water without exposure to HS, and the 4th (G4) birds exposed to HS and administered prebiotics in drinking water. After each vaccination, blood samples and serum samples were collected to evaluate the birds’ immune status. Fecal samples were also collected for the molecular evaluation of the gut microbiome based on the genetic analyses and sequencing of 16S rRNA gene. The results showed that HS has reduced the birds’ performance and badly affected the birds’ immune response and gut microbiome. However, the addition of prebiotics to drinking water, with or without stress, enhanced the growth rate, maintained a normal gut microbiome, and improved immune parameters. Moreover, the usage of prebiotics improved the chicken gut microbiome and alleviated the negative effect of heat stress. Administering prebiotics significantly (p < 0.05) increased the relative abundance of beneficial bacteria and eradicated pathogenic ones in the birds’ gut microbiome. Prebiotics showed a positive effect on the gut microbiome and the immune status of chickens under HS in addition to their efficacy as a growth promoter.

Safety assessment of Enterococcus lactis strains complemented with comparative genomics analysis reveals probiotic and safety characteristics of the entire species

“…The DNA was reconstituted in 50 µl nuclease free water and stored at -20 ºC. The concentration and quality of the DNA were measured using a NanoDrop ND-1000 spectrophotometer (Thermo Fisher Scientific, USA) [ 29 ]. High purity genomic DNA expressing an OD260/OD280 ratio of 1.8–2.0 was used for whole-genome sequencing [ 30 ].…”

Alleviating heat stress effects in poultry: updates on methods and mechanisms of actions

“…These include essential oils, organic acids, symbiotics, prebiotics, probiotics, enzymes, and phytogenes such as oleoresins, botanicals, and herbs ( 64 ). Besides their effectiveness as growth promoters, prebiotics have also been shown to have a beneficial impact on the gut microbiome and immunological condition of birds during heat stress ( 65 ). Intensifying the use of natural antibiotic alternatives as growth promoters on a large scale provides safe and healthy substitutes that possess a wide range of beneficial properties such as immune-modulating effects, enhanced digestion, improved performance, improved nutrient absorption, increased absorbability, improved gut health, lesser risk of antibiotic resistance, and safe consumption of poultry products.…”