PSVIII-B-3 Comparison of Telomere Length in Leukocytes of Control and Prenatally Stressed Brahman Bull and Heifer Calves

Abstract Telomeres are comprised of G-rich nucleotide sequences (5’-TTAGGG-3’) at the chromosome termini that responsible for protecting chromosomes; however, attrition these has been observed due to aging and stress. The purpose this study was compare telomere length (TL) in control prenatally stressed (PNS) calves. Mature Brahman cows inseminated a single sire 2018 were assigned be either Control (n=35; not transported) or PNS (n=37; 2 h transportation 60, 80, 100, 120, 140±5 d gestation). Jugular blood samples obtained by venipuncture from 10 (5 bulls 5 heifers) calves 25±2 age. Peripheral leukocytes isolated genomic DNA extracted utilizing silicone membrane spin column kits. relative quantity products, which is proportional average TL, determined multiplex quantitative PCR analysis using ratio bovine β-globulin (T/S ratio). An absolute standard (1012–107 dilution series) (109-104 genes utilized produce copy number. All processed triplicate included if Cq difference less than 0.25 cycles. Data analyzed ANOVA. TL differed sex (P< 0.03; 11,959±211; heifers 12,850±366) treatment 0.02; 12,895±278; 11,913±303). There an interaction (P >0.43) although (13,482±396) exceeded (11,609±348). These observations fewer copies suggest influence on within 1 month age; and, prenatal stress may increase telomeres cattle. Support: USDA NIFA Award No. 2019-67015-29573