Addition of a protected complex of biofactors and antioxidants to breeder hen diets confers transgenerational protection against Salmonella enterica serovar Enteritidis in progeny chicks

Authors: Swaggerty, Christina - Christi; MALHEIROS, RAMON - North Carolina State University; LAHAYE, LUDOVIC - Jefo Nutrition Canada; Byrd Ii, James - Allen; Genovese, Kenneth - Ken; He, Louis; SANTIN, ELIZABETH - Jefo Nutrition Canada; Kogut, Michael - Mike

Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/19/2023
Publication Date: 1/24/2023
Citation: Swaggerty, C.L., Malheiros, R.D., Lahaye, L., Byrd II, J.A., Genovese, K.J., He, L.H., Santin, E., Kogut, M.H. 2023. Addition of a protected complex of biofactors and antioxidants to breeder hen diets confers transgenerational protection against Salmonella enterica serovar Enteritidis in progeny chicks. Poultry Science. 102(4). Article 102531. https://doi.org/10.1016/j.psj.2023.102531.
DOI: https://doi.org/10.1016/j.psj.2023.102531

Interpretive Summary: Poultry producers are looking for alternative products to replace antibiotics. As such, natural products including plant extracts, botanicals, or essential oils are being used more and more as antibiotic replacements, and in most cases, these products are added to the feed when chicks are placed for the grow-out phase. Very little is known concerning the ability of these natural products to result in healthier, more robust chicks that are more resistant to foodborne pathogens such as Salmonella. The purpose of this project was to see if hens fed a diet supplemented with a natural botanical product produced chicks with a better immune response that makes them more resistant to Salmonella infections. Baby chicks hatched from hens fed the supplemented and control diets were infected with Salmonella. Four and 11 days after infection, some of the chicks were terminated to determine if the ones from the supplement-fed hens had lesser amounts of Salmonella compared to those from hens on the control diet. At both timepoints, there were far fewer chicks from the supplement-fed hens with detectable levels of Salmonella compared to the chicks from the control-fed hens. In addition to fewer Salmonella-positive chicks, those that were infected had smaller numbers of Salmonella that could be recovered. Once we knew the chicks from the supplement-fed hens were more resistant to Salmonella, we wanted to find out why. The immune response sends out small chemical messengers (cytokines) that helps direct a strong immune response against infections, including Salmonella. The chicks from hens on the supplemented diet had stronger cytokine responses that helped them fight off the Salmonella and kept them healthier than the chicks from the control-fed hens. In summary, this study showed that feeding hens a diet supplemented with a natural botanical, produced baby chicks with a strong immune response and having more resistance to Salmonella. A healthier chick will grow up to be a healthy bird entering the food chain; therefore, less likely to pass on microbes like Salmonella, thus creating a safer food supply for the consumer.

Technical Abstract: Addition of botanicals or other natural products as feed additives is becoming commonplace practice in the poultry industry as producers rely less on antibiotics; however, less is known regarding their use in broiler breeder hens. The objective of this study was to determine if feeding a botanical to broiler breeder hens conferred resistance against Salmonella enterica serovar Enteritidis in the progeny chicks. Three-day-old chicks from control- and supplement-fed hens were challenged with S. Enteritidis and necropsied 4- and 11-days post challenge (dpc) to determine if there were differences in invasion and colonization. Serum and jejunum were evaluated for various cytokine and chemokine production. Fewer (P=0.002) chicks from supplement-fed hens had detectable S. Enteritidis in the ceca (32.6%) compared to chicks from control-fed hens (64%). By 11dpc, significantly (P<0.001) fewer chicks from supplement-fed hens were positive for S. Enteritidis (liver [36%]; ceca [16%]) compared to chicks from the control hens (liver [76%]; ceca [76%]). The recoverable S. Enteritidis in the cecal content was also lower (P=0.01) 11dpc. In additional to the differences in invasion and colonization, cytokine and chemokine production were distinct between the two groups of chicks. Chicks from supplement-fed hens had increased production of IL-16, IL-6, MIP-3alpha and RANTES in the jejunum while IL-16 and MIP-1beta were in the serum of chicks from the control-fed hens. By 11dpc, production of IFN-gamma and VEGF were decreased in the jejunum of chicks from supplement-fed hens. Collectively, this data demonstrates that addition of the botanical feed additive to the diet of broiler breeder hens offers a measure of transgenerational protection of the offspring against S. Enteritidis infection and reduces colonization that is mediated, in part, by a robust and distinct cytokine and chemokine response locally at the intestine and systemically in the blood.