EFFECT OF GLYPHOSATE ON GUT MICROBIOME BIOMARKERS ASSOCIATED WITH REPRODUCTIVE LONGEVITY IN LAYING HENS

Abstract

Glyphosate is herbicide that is now widely used in agriculture. Glyphosate has a direct effect not only on plants but also on the gut microbiome of farm animals and poultry. This study examined the effects of glyphosate on the gut microbiome biomarkers of laying hens depending on their reproductive longevity. The results of the study revealed a relationship between glyphosate exposure, the composition of the gut microbiota, and the productive longevity of laying hens. It was found that the herbicide can induce changes in the bacterial community. Glyphosate had the most significant effect on the Firmicutes/Bacteroidota ratio. In the group with high reproductive longevity, glyphosate led to a 6.36% increase in Firmicutes and a 5.78% decrease in Bacteroidota. In the group with low reproductive longevity, it increased Firmicutes by 3.44% and decreased Bacteroidota by 4.05%. These microorganisms can be considered markers reflecting the negative impact of the herbicide on the microbiome. Glyphosate reduced the proportion of groups responsible for fiber fermentation and short-chain fatty acid synthesis, such as Bacteroidetes and Ruminococcaceae. Furthermore, laying hens from a line with high reproductive longevity were found to exhibit significantly greater resistance to the negative impact.