Adaptation of the White Fulani cattle to the tropical environment.

This review summarizes the available information on the adaptation and the performance of White Fulani cattle in tropical environments. White Fulani cattle is an indigenous breed of cattle widely distributed in the humid tropical regions of Africa and plays significant roles in meat and milk production, as well as draught purposes. Poor management and the harsh environmental conditions in the tropics encumber the optimal productive and reproductive performance of the breed, having about 4.75 years age at first calving, 57% calving rate, 18 months calving interval and 3 to 4 calves are born in a reproductive lifetime. The cattle breed adapts to these climatic patterns via physiological, morphological, behavioral, genetic, and metabolic responses. Different physiological mechanisms and morphological features such as their white coat color, hair coat thickness, and lengthy rump appear to play an important adaptive role. The distinct genetic traits (including the possession of seven genetic variants of HSP 90 gene) of the breed afford them some levels of thermotolerance and high resistivity to some endemic diseases (such as trypanosomiasis, liver fluke, brucellosis and foot and mouth disease) in the tropics constitute inherent characteristics that should be explored in detail using molecular assisted approaches. The productive performance of the breed under different systems is discussed. A better understanding of the adaptive characteristics of White Fulani cattle could provide crucial information on the best management approach/techniques that should be adopted to improve the performance, productivity, and sustainability of this cattle breed. Therefore, this review aims to compile the various production, reproduction and adaptation traits of the breed and presents vital information underlying their thriving and survivability in tropical environments.

Environmental stress and livestock productivity in hot-humid tropics: Alleviation and future perspectives.

Tropical environments are characterized by persistently high temperature and relative humidity and the harsh environmental conditions pose a serious limitation on the optimal performance of the animals raised in this region. Heat stress causes deleterious effects on welfare, immunology and physiology of farm animals with a resultant impact on their productivity as the use of body resources is re-organized and the metabolic priorities of animals shift away from production, growth, health and reproduction. It is imperative to understand the mechanisms involved in the thermoregulation of animals under tropical conditions in order to develop appropriate strategies for their improvement. This review focuses on the available data on the increasing global temperature and the adverse impact of tropical conditions on animals' adaptive mechanism affected during thermal stress on production performance, intestinal and ileal microbiome, physiological responses, antioxidant system, metabolic responses, cellular and molecular response, adaptive mechanism strategies to heat stress and also strategies to palliate environmental stress on livestock under humid tropical conditions including environmental manipulation, genetic opportunity, epigenetic and feeding modification. Overall, the present review has identified the disturbance in the physiological indices of tropical livestock and the need for concerted efforts in ameliorating the adverse impacts of high ambient temperature aggravated by high humidity on livestock in tropical environments. Further research is needed on genotype-by-environment interaction on the thermotolerance of different livestock species in the tropics.

Evaluation of sweet citrus peel supplement in water on performance and ileal microbial count of broiler chickens.

The effect of supplementing drinking water with sweet citrus peel powder (SCPP) on the performance, ileal microbial count, and relative weight of organs of broiler chickens reared in a tropical environment was investigated. Ninety-six (96) 1-day-old Ross broiler chickens, after brooding, were randomly allotted into four treatment groups: T1 (control) received drinking water without SCPP, while birds in T2, T3, and T4 were given water supplemented with 2, 4, and 6 g of SCPP per liter of water, respectively. Each treatment was replicated three times with eight birds per replicate in a completely randomized design. Feed intake and weight gain were not significantly (p > 0.05) different among the treatments. However, significant variations (p < 0.05) were observed in the final weight and feed conversion ratio (FCR) with birds on T4 (6 g SCPP) having the highest final weight of 2164.60 g and the lowest FCR of 2.11 compared with 1838.40 g final weight and 2.40 FCR recorded for birds in the control group. Total bacteria count (TBC) of 2.07 × 106 CFU/ml (T1), 1.20 × 106 CFU/ml (T2), 1.27 × 106 CFU/ml (T3), and 1.33 × 106 CFU/ml (T4) recorded showed no significant (p > 0.05) variations among the treatments. However, orthogonal contrast between control and SCPP treatment groups showed significant variation (p < 0.05) in TBC. Significant variations (p < 0.05) were observed in the live weight and relative weight of heart and pancreas. Higher live weight with lower FCR and TBC recorded in this study showed the positive effect of SCPP on the performance and ileal microbial count of broiler chickens.