Transcriptomic responses of in ovo delivered bioactive substances in heat-stressed broiler chickens

Poultry constitutes one of the most consumed animal proteins globally; thus, the poultry industry currently sustains the food security of billions of people. Despite the importance of the poultry industry, the welfare and performance of poultry birds are being impaired by environmental and regulatory factors regarding the use of antibiotics. Heat stress (HS) has explicitly been regarded as "the main environmental factor" negatively impacting the poultry sector. HS occurs when the heat generated in the body surpasses its dissipation ability and the animal becomes incapable of getting rid of excess heat. Poultry lacks sweat glands and has an increased metabolic rate due to selection for rapid growth; hence they are more vulnerable to HS, which causes significant economic losses to the poultry industry. The economic impact of HS on the poultry industry is up to $165 million in annual losses. Several bioactive substances have been reported to have HS mitigative and antibiotic replacement properties. However, the conventional routes of bioactive substance delivery, i.e., via the feed or water, limit their efficacy. Delivering these substances via the in ovo route might help overcome the limitations of the conventional delivery routes and enhance their HS mitigating and antibiotic replacement capacities. Therefore, this study intends to utilize molecular biological techniques to evaluate broiler chickens' response to a mimicked summer heatwave. The HS mitigating potential of in ovo delivered bioactive substances (probiotics, folic acid, and essential oil) will also be determined. Outcomes from this study could help solve two critical challenges facing the global poultry industry, finding an effective alternative to antibiotics and HS mitigation. This research will ensure optimal gut health development in broiler chickens, hence dismissing the need for antibiotic use. In collaboration with a Professor of Avian Endocrinology and Molecular Genetics, at the Center of Excellence for Poultry Science, University of Arkansas, USA, we will determine the immune and intestinal barrier-related gene expression, using genomic and transcriptomic tools. A Ph.D. student will be trained by both participating researchers.