Distribution and spatiotemporal development of organised lymphoid tissues in the chicken intestinal tract

Cannabidiol and nano-selenium mediate intestinal barrier function by affecting mucosal microstructures, and gut-associated immunological and oxidative stress response in the gut of chickens infected with C. perfringens

Nutritional additives with biological activity, such as cannabidiol (CBD) and nano-selenium (nano-Se), are viable to prevent bacterial diseases such as necrotic enteritis in chickens. The present study hypothesized that CBD and nano-Se mediate epigenetic and oxidative DNA changes in blood and intestinal epithelial cells and can affect intestinal development and functionality in broiler chickens at an early stage of infection with C. perfringens. This study revealed that both compounds, in combination under physiological or pathophysiological conditions, can act synergistically, improving the indices of histomorphometry of duodenum, jejunum, and ileum. Examination of the structures and ultrastructures of the gastrointestinal tract showed that CBD + nano-Se supplementation did not manifest adverse effects on the host gut indices. In contrast, epigenetic and oxidative markers of blood and gut structures indicated that these components balanced the immune system, mitigating the excessive inflammatory response caused by infection, which boosted the immune response of birds to challenge. There were also significant correlations between indicators of intestinal barrier function, such as diamine oxidase and lactic acid levels, and histomorphometry and markers of DNA integrity in the blood and intestine of chickens. In addition, it was shown that nano-Se increased hemoglobin concentration, which may be beneficial in the host's response to pathogen stimuli. These findings evidenced the health-promoting effect of cannabidiol and nano-selenium in C. perfringens-infected chickens and provided new insights into the mechanism of action of both nutritional additives.

Benzoic Acid potentiates intestinal IgA response in broiler chickens against Salmonella enterica Serovar Typhimurium infection

As a feed additive, Benzoic Acid (BA) has been demonstrated to significantly enhance feed conversion efficiency, regulate gastrointestinal pH, and improve overall animal health. Young animals, highly susceptible to S. Typhimurium infection, suffer from high mortality rates and substantial economic losses due to this pathogen. Despite promising indications of BA's immunomodulatory potential in boosting intestinal immunity, its underlying mechanisms remain insufficiently understood. This study investigates how BA strengthens intestinal anti-infection defenses in young animals via immunomodulatory pathways, focusing on its impact on macrophage polarization and IgA-mediated immune responses. Employing in vitro cell experiments and animal models, we examined the macrophage phenotypic alterations following BA treatment. We assessed the expression of immune-related genes in the intestine through immunofluorescence staining, Western blotting, and quantitative real-time PCR. The results demonstrate that BA promotes M2 macrophage polarization by activating the mTOR/PPAR-γ/STAT3 signaling pathways. Furthermore, BA enhances the intestinal expression of the polymeric immunoglobulin receptor (PIgR), B-cell activating factor (BAFF) from the TNF family, and activation-induced cytidine deaminase (AID), thereby enhancing IgA production by B-cells. These results underscore the potential of BA to bolster innate immune functions in young chickens, mitigate intestinal damage caused by S. Typhimurium infection, and ultimately promote both animal health and food safety.

Discrimination of distinct chicken M cell subsets based on CSF1R expression

In mammals, a subset of follicle-associated epithelial (FAE) cells, known as M cells, conduct the transcytosis of antigens across the epithelium into the underlying lymphoid tissues. We previously revealed that M cells in the FAE of the chicken lung, bursa of Fabricius (bursa), and caecum based on the expression of CSF1R. Here, we applied RNA-seq analysis on highly enriched CSF1R-expressing bursal M cells to investigate their transcriptome and identify novel chicken M cell-associated genes. Our data show that, like mammalian M cells, those in the FAE of the chicken bursa also express SOX8, MARCKSL1, TNFAIP2 and PRNP. Immunohistochemical analysis also confirmed the expression of SOX8 in CSF1R-expressing cells in the lung, bursa, and caecum. However, we found that many other mammalian M cell-associated genes such as SPIB and GP2 were not expressed by chicken M cells or represented in the chicken genome. Instead, we show bursal M cells express high levels of related genes such as SPI1. Whereas our data show that bursal M cells expressed CSF1R-highly, the M cells in the small intestine lacked CSF1R and both expressed SOX8. This study offers insights into the transcriptome of chicken M cells, revealing the expression of CSF1R in M cells is tissue-specific.