Temperature – Humidity Index (THI) of Rabbits in a Tropical Environment as Influenced by Dietary Cocoa Pod Husk Meal

Abstract

The temperature – humidity index (THI) of cross bred rabbits fed differently processed forms of cocoa pod husk meal based – diets was evaluated using sixty animals (24 bucks and 36 does with mean body weight of 606.42±1.30g). Twelve experimental diets were formulated containing raw, fermented and hot – water treated cocoa pod husk meal (CPHM) at 0, 12.5, 25 and 37.5 percent levels each. The rabbits were subjected to nine weeks feeding trial in a completely randomized design during which records of daily ambient temperature and relative humidity were taken using digital thermometer (LCD Digital Thermo - Hygrometer, model MT - 3 with sensor for indoor/outdoor temperatures and relative humidity display at the same time) throughout the study period. The rectal temperature of each rabbit was taken twice at 3 – 4 days interval on a weekly basis with the aid of a clinical thermometer (Ocean med+ England model). The thermometer was inserted into the rectum of the rabbits to a certain depth and reading was taken after 50 – 55 seconds when the mercury level stopped rising. The THI was calculated using appropriate formula. Results showed that the average rectal temperature was between 38.30° and 38.63 ℃ while the mean indoor and outdoor temperatures were 29.27 ± 0.04° and 28.72±0.18℃ respectively and relative humidity of the rabbitry was 39.30±0.51% with the THI at 26.44; which was less than the critical value of 27.80, implying absence of heat stress. The study concluded that feeding raw, fermented and hot – water treated cocoa pod husk meal based-diets up 37.5 % to rabbits will not imposed additional heat load (heat stress) on the animals in the tropics and therefore establishes the THI of rabbits in a typical tropical environment as 26.44. Farmers are strongly advised to adopt this agro – industrial by –product in diets meant for rabbits in the tropics.