Impact of peanut skin supplementation and salmonella challenge on gut microbiota of broiler chickens.

Authors: TAHIR, YABAIZ - North Carolina State University; WALKER, LIN - North Carolina State University; LOWERY, JUSTIN - North Carolina State University; ANDERSON, LAUREN - North Carolina State University; ROBERTS, NATALIE - North Carolina State University; Vu, Thien; Toomer, Ondulla; Proszkowiec-Wegla, Monika

Submitted to: International Poultry Scientific Forum
Publication Type: Abstract Only
Publication Acceptance Date: 12/30/2025
Publication Date: N/A
Citation: N/A

Interpretive Summary: Salmonella is the leading cause of bacterial food-borne zoonoses and is a predominate public health concern. Hence, in this study we aimed to examine the use of alternative feeding strategies to alter the gut microbiota of poultry and reduce the prevalence of food borne pathogens such as Salmonella. In this study we compared the gut microbiota of birds that were either non-inoculated or inoculated with Salmonella and fed a conventional corn/soy diet or a conventional corn/soy diet supplemented with ground peanut skins (5%) for 6 weeks. This study demonstrated that use of peanut skins as a poultry feed additive enhanced the overall diversity and health of the gut microbiota, while Salmonella inoculation alone significantly disrupted the microbial diversity of the gut microbiota. These studies suggest that dietary inclusion of peanut skins in poultry diets may promote microbial stability and reduce the predominance of Salmonella and other food-borne pathogens within the gut.

Technical Abstract: Salmonella, a major foodborne pathogen in poultry production, poses a health risk to human health. This study evaluated the outcomes of the presence of peanut skin (5%) in the diet on cecal and ileal microbiota in Salmonella Typhimurium-challenged birds. A 2 x 2 design was used to randomly assign 180-day-old Ross 308 chicks into four treatments: CON (control diet, uninfected), PS (peanut skin diet, uninfected), CONS (control diet with Salmonella), and PSS (peanut skin diet with Salmonella). At the end of the trial (day 44), cecal and ileal contents were aseptically collected from 12 birds/treatment for microbiota analysis. Sequencing of the V3-V4 hypervariable region of the 16S ribosomal RNA (rRNA) was performed using Illumina’s MiSeq platform and was analyzed using QIIME2 software. Statistical analysis was performed using nonparametric tests, with a significance level of p < 0.05. In the cecum, evenness, the number of amplicon sequence variants (ASVs), and Shannon Index did not differ significantly among dietary treatments. Regarding richness, a difference was observed between CON and PS groups (p = 0.05); however, richness was higher in non-challenged birds than in challenged birds (p = 0.0004). Unweighted UniFrac PERMANOVA indicated strong compositional shifts (p = 0.001), where challenged birds clustered away from the non-challenged groups. In the ileum, evenness was unaffected (p < 0.05); however, richness, ASVs, and Shannon Index in non-challenged birds were significantly different (p < 0.05) compared to challenged birds. PS also showed a significant difference (q < 0.05) compared to CON across all metrics except for Shannon Index (q > 0.05). Unweighted UniFrac showed distinct microbiota clustering in non-challenged groups compared to the challenged groups (p = 0.001), though less distinctly than in the cecum. Overall, CON and PS diets differed in initial metrics, suggesting differences in healthy microbiota structure; however, diversity was greatly reduced after Salmonella challenge. PS supplementation produced significant effects, especially in the ileum. These results suggest that infection is a major factor in the shift of intestinal microbiota, but dietary PS may promote microbial stability. Further research is in progress to clarify host microbiota interactions.