Evaluation of Heat stress Impact on Coat Color pattern and physiological responses of West African Dwarf goats in South Western Nigeria

This study evaluated the impact of heat stress on different coat color patterns and the associated physiological responses of West African Dwarf (WAD) goats in South-Western Nigeria. Thirty clinically healthy WAD goats were assessed in Iwo, Osun State, a region characterized by high ambient temperature and humidity that predispose animals to thermal strain. Physiological indicators of heat stress rectal temperature (RT), respiration rate (RR), and heart rate (HR) were measured across goats with varying coat color patterns. Concurrently, meteorological parameters including ambient temperature and relative humidity were recorded to compute the Temperature Humidity Index (THI). The THI values (79.46–90.99) confirmed that all goats were exposed to moderate to severe heat stress during the study period. Significant differences (p < 0.05) were observed in physiological responses among coat color categories. Goats with darker coat patterns, particularly black and black-mixed colors, exhibited higher RT, RR, and HR compared to lighter-colored counterparts, indicating reduced thermotolerance. Additionally, male goats showed higher respiration rates than females, suggesting sex-related variation in heat adaptation. The findings demonstrate that coat color pattern plays a crucial role in heat stress susceptibility, with darker-coated WAD goats being more vulnerable to thermal load. Therefore, lighter-colored coat patterns may serve as a more suitable selection criterion for breeding programs aimed at improving heat resilience in hot and humid environments of South-Western Nigeria.