Food and Environment

by Yadav Sharma Bajagai Swine are particularly susceptible to increased environmental temperature because evaporative cooling by sweating is of limited value to them due to barely functional sweat glands. Impacts of thermal stress on pig due to increased ambient temperature are described here briefly.   For Impacts of Climate Change on Cattle , Click Here.

by Yadav Sharma Bajagai Reduction in milk production is one of the major economic impacts of climatic stress in dairy cattle. Decrease in milk yield due to heat stress is more prominent in Holstein than in Jersey cattle [ 1 ] . Decreased synthesis of hepatic glucose and lower non esterified fatty acid (NEFA) level in blood during heat stress [ 2 , 3 , 4 ] causes reduced glucose supply to the mammary glands resulting low lactose synthesis which in turn ensues low milk yield [ 5 ] . Reduction in milk yield is further intensified by decrease in feed consumption by the animals to compensate high environmental temperature [ 5 , 6 ] .

by Yadav Sharma Bajagai Any physiological, metabolic, behavioral and performance abnormality in animals due to inability of thermoregulatory mechanism to regulate normal body temperature during high ambient temperature can be referred to as heat stress. Heat stress is not only the concern of only tropical region but also a matter of major apprehension in sub-tropical and temperate regions too as frequent spells of high ambient temperature and gradual rise in global atmospheric temperature is being experienced in many of the temperate regions of the world due to global climate change. Heat stress is one of the greatest climatic challenges faced by horses affecting animal health and welfare in the area of the world where ambient temperature often exceeds upper critical temperature.  Principle of management of heat stress during hot weather is to hasten the heat loss and avoid the heat gain as far as possible.

Major M echanisms that A nimals use to C ontrol B ody T emperature (Thermoregulatory Mechanisms in Animals) by Yadav Sharma Bajagai Major Impacts of climate change on animals are due to thermal stress resulting from increased ambient temperature. This article has been posted to illustrate how animals control their body temperature. This will help to find/design adaptation methods against climate change effects.  The first line of defense animal use to maintain body temperature in unfavorable ambient temperature is behavioral response to manage heat loss or gain [ 1 ] . Seeking shelter in hot day or sun in cold day and altering body posture according to temperature to minimize or maximize relative body surface area to alter heat loss or gain are major behavioral response to maintain body temperature by cattle [ 1 ] . Animals can maintain its body temperature within narrow range irrespective of ambient temperature due to metabolic heat production [ 2 , 3 ] ...

  by Yadav Sharma Bajagai 1     Introduction Warming of climate system of the earth is a unanimously accepted reality [ 1 ] and probably one of the most prominent challenges for scientists, development workers, policy makers and other relevant stakeholders regarding development and sustainability in international and national arena during past several years. Intergovernmental panel on climate change (IPPC) has described climate change as any anthropogenic or naturally occurring alteration in the climate over time [ 1 ] . The World Bank has published ‘world development report 2010’ with the title “development and climate change” as an example to depict the importance of this issue. Global warming is attributable to increase in atmospheric concentration of green house gases (mainly CO 2, CH 4 and NO 2 ) as a result of human activities since the industrial revolution [ 1 , 2 ] . Concentration of total green house gases in the atmosphere has been i...