Expression of Two Heat Tolerant Genes and Their Relationship With Thermoregulatory Traits in Some Indigenous Cattle in Mubi

Eighty (80) clinically healthy lactating cow breeds (Adamawa Gudali, Bokoloji, Bunaji, and Rahaji), 20 per breed were selected, and blood samples were collected from 16 cows (4 per breed) between February and April 2024. Gene expression was analyzed using real-time PCR (qPCR), evaluating the ∆Ct values for Heat Shock Protein (HSP90AA1) and prolactin receptor gene (PLRL) genes. Thermoregulatory parameters: rectal temperature (RT), respiration rate (RR), pulse rate (PR), and heat tolerance coefficient (HTC), were measured at 8:00 am and 2:30 pm throughout the study period. Significant (P < 0.05) positive correlations were found between PLRL and RR (r = 0.48), HTC (r = 0.42), and PR (r = 0.79), while a negative correlation existed between PLRL and PR (r = -0.38). HSP90AA1 showed positive relationships with RR (r = 0.61), PR (r = 0.51), and HTC (r = 0.59), A significant negative association was observed between HSP90AA1 and PR (r = -0.52), and between HSP90AA1 and HTC. Overall, the study highlighted complex but significant interactions between stress-related gene expressions and thermoregulatory traits in indigenous cattle breeds, indicating their potential as genetic markers for heat stress adaptation in tropical environments. It is recommended that, Adamawa Gudali breed should be used for improvement of heat tolerance because of its high adaptation during the hot period of Mubi, compared to Red Bororo, Sokoto Gudali and Bunaji breeds.