Effect of the Microclimatic Temperature-Humidity Index (THI) on the Productivity Performance of Rabbit

Temperature-humidity index (THI) is a useful and easy way to assess the risk to heat stress. This index combines effects of environmental temperature and relative humidity. This study was conducted to determine the temperature-humidity index and to assess its effects on breeding does’ productivity potential at the rabbit house of the University of Benin Teaching and Research Farm. Data on microclimatic factors of ambient temperature (TEMP) and relative humidity (RH) of the rabbit house were obtained on monthly bases for 1 year. The year was divided into four seasons: late dry (January to March), early rain (April to June), late rain (July to September), and early dry (October to December). Temperature-humidity index was calculated using the ambient temperature and relative humidity values obtained on monthly and seasonal bases. The estimated values for TEMP were 34.78 ± 0.17, 33.41 ± 0.22, 31.17 ± 0.22, and 33.55 ± 0.19°C for late dry, early rain, late rain, and early dry seasons, respectively (p < 0.05), and the corresponding RH values were 56.89 ± 0.17, 57.23 ± 0.16, 59.03 ± 0.25, and 57.17 ± 0.20% (p < 0.05). The highest and lowest THI values were reported in late dry (32.03 ± 0.14) and in late rain (29.03 ± 0.19) (p < 0.05), in agreement with the higher and lower thermal stress in these seasons. In relation to the productivity of does, percentage conception rate ranged from 0 to 20% in late dry vs. from 52 to 56% in late rain. In conclusion, the most favorable season was late rain with the lowest THI and the highest productivity potential parameters