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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.

This research was influenced by the need to eradicate voltage selection error in manual battery-charging, as well as the necessity for getting more batteries charged within a short duration without compromising the cycle life of a battery. Minimizing human interference in charging of batteries as a means of making the process stress-free, safer and faster is also a motivation for this work. This paper presents a battery charger which takes accurate decisions by itself and eliminates poor charging parameters which can damage even brand new batteries. The battery charging unit automatically senses the battery terminal voltage(s), supplies appropriate charging voltage/current, and terminates charging process based on preset operational conditions of voltage, current and temperature. Key components of the developed prototype include PIC16F877A microcontroller chip, LLC resonant converter, and an LCD based display unit. The chip runs dedicated codes that control all tasks involved in the operation of the charger. Pulse-width modulation (PWM) technique was employed to control switching duty cycle which consequently varies the output of the converter and enables battery-charging from 6-volt to 48-volt. Before embarking on the actual constructions, simulations were done to evaluate the performance of the system. The model was subjected to tests under various load conditions and the results agreed with objectives of the research.

Goat plays a vital role in the rural village economy and are critical for food security and livelihood. The contributions of goats to the economy of millions of rural people notwithstanding are hindered by severe heat stress due to the global climate change. Prediction of climate change impact indicate that heat stress is the overriding factor influencing native habitats of different species of domestic animals and is an important determinant for either survival of each species in its current state with consequent decline in performance or in more severe conditions, species extinction. However, West African Dwarf (WAD) goats surpass other ruminants and have optimally adapted to harsh environmental conditions because of their unique adaptive traits. The goats can adapt to heat stress through a combination of morphological, behavioral, physiological and genetic traits. This review paper therefore, provides an update of integrative facts of potential impact of global climate change, and unique adaptive traits of WAD goats responsible for their resilience to environmental stress. The elucidation of the mechanisms involve in WAD goats’ adaptation may facilitate adoption of comprehensive control measures to ameliorate the impact of environmental stress in domestic animals.