6455 The Effect of Gene Silencing on Inhibiting Stress Hormones in Wild Birds Raised Under Stressful Conditions

Abstract

Abstract Disclosure: S.M. Abdulateef: None. T. Mohammed: None. W. Al-Jugif: None. M.Q. Abed: None. Wild birds are notable for their ease of rearing, tolerance to extreme environmental conditions such as heat and cold, and their resistance to diseases. They are also recognized for their ability to withstand stress. However, their primary challenge is low egg production, stemming from their aggressive nature. This aggression elevates the secretion of stress and fear hormones, significantly impacting reproductive hormones. This study aims to explore the effects of gene silencing on the physiological traits of wild birds, particularly its influence on physiological responses and the reduction of stress hormone levels. Three treatments were employed: T1 (control), T2 (welfare treatment, wherein birds were raised with enhanced well-being), and T3 (using siRNA technology to silence the gene responsible for stress hormone corticosterone production). The silencing of CYP11B1 and CYP11B2 involved obtaining the cDNA of each gene from the NCBI, associated with corticosterone production. The coding sequence from the 5' end at the cap direction was reversed to complement mRNA. Two siRNAs were procured from Macrogene Company (South Korea) in lyophilized form at high concentration, with sequences: CYP11B2 5'-acacctctgcctttgccctgagtgccat-3' and CYP11B1 5'-ctaaagtcaaactcagccccacattcat-3'. These were dissolved in molecular-grade distilled water for a final concentration of 500 pmol/µl. Each hen was injected in the wing in the jugular artery with 125 µl of the siRNA solution at 14 and 18 weeks of age, before the commencement of the egg-laying cycle. Corticosterone levels were measured using the Sunlong Biotech CO., LTD kit. The results showed a significant decrease (p<0.01) in stress hormone levels in the third treatment group (gene silencing treatment), leading to notable physiological responses in the birds compared to the other treatments. This study highlights the impact of gene silencing on the physiological traits of wild birds and its effects on their physiological responses. The findings of this study are significant in the context of avian physiology and poultry farming. By elucidating the impact of stress hormones on egg production and demonstrating the efficacy of gene silencing as a method to enhance reproductive efficiency, this research opens new avenues for improving the productivity and well-being of wild birds in controlled environments. It also underscores the potential of genetic interventions in addressing physiological challenges in wildlife. Presentation: 6/1/2024