Livestock Production Case Study

BASE PAPER FOR BRAINSTORMING SESSION ON
Climate Resilient Livestock Production
1. Justification and relevance of the subject:
The demand for animal products and by-products is continuously increasing in India due to un-abatable increase in human population, change in food habits, increase in disposable income and urbanization. In spite of around 4 per cent growth in livestock sector and country being the highest milk producer in the world, wide gap exists in demand and supply of animal food products. The contribution of livestock sector in the agricultural gross domestic product is around 30 per cent which will further increase in future. Livestock production in India is predominantly in small holding farming system. Crop residues with little
A lack of appropriate physiological models that relate climate to animal physiology rather limit the confidence that can be placed in prediction of impacts. It is, however, well documented that warming will alter heat exchange between animal and environment and, feed intake, growth, reproduction, health and production are all affected potentially. The thermoregulatory mechanism like increase in respiration rate and pulse rate as initial response to increase in ambient temperature above upper critical temperature incur energy expenditure and thus adversely affect the production. Producing animals face heat stress during summer and rainy season in India and further rise in temperature will have additive impact. Although the animal gets acclimatized to prolonged exposure to that particular temperature but this adaptation is at the cost of production. If the physiological and behavioural responses are insufficient to maintain thermal balance the animal tries to restrict the feed intake to reduce the internal heat load. Intake of digestible nutrients is most often the limiting factor in animal production and then
Abrupt environmental temperature changes above critical level reduce the conception rates. The drop in fertility when the maximum temperature the day after breeding exceeds upper limit of zone of homeothermy are of concern in context of climate change. Stress full environmental temperature triggers blood flow changes that reduce the flow of blood to the uterine tract, damaging, or killing the developing embryos. Uterine blood flow is source of oxygen, water, nutrients and hormones for embryos. It also carries excessive, damaging heat away from the embryos. Zygotes are most vulnerable to heat stress in initial stages of cleavage. Heat stress is a major cause of early embryonic losses and with further increase in temperature it may increase. A reduction of 3-4 per cent in conception rates has been observed in cows when THI reaches above 70 (Hahn, 1995; Anderson et. Al., 2005). Such information is not available for Indian farm animals. Silent heat and low conception rates during summer in buffaloes is already a serious problem in northern India. It is not that reproduction in females is affected, in males also the semen quality get