Adaptation to Hot Environment in Sheep and Goat
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ABSTRACT
In this article we will come to know how various adaptive behaviors shown by Sheep and Goat during hot environmental conditions. High rise in ambient temperature leading to decline in production and various changes in normal behavior to cope up with the conditions. Sheep and goat both are well tolerant to heat but goats are more heat resistant in comparison to sheep. Various important adaptive behaviors shown by these two species are panting, evaporation and increase in water intake.
Key words: Adaptive behavior, hot environment, panting, evaporation etc.
INTRODUCTION
Sheep and Goat are closely related species and living with human being since a long across the globe. Sometimes it becomes difficult to differentiate in between them. One of the important feature to distinguish in between is on the basis of tail, tail of goat turns upward where as it is not so in case of sheep. Both sheep and goat are considered as heat resistant but in general goats are more resistant to heat stress. Goats are more intelligent and curious in comparison to sheep.
Sheep have well adaptations towards cold climatic conditions but they also have remarkable heat tolerance, though this tolerance is not up to the level of goats. When ambient temperature lies between 370C to 400C their body temperature remains normal. When environmental temperature rise beyond this level sheep maintain their body temperature by panting and evaporation from respiratory system. These two are most important mechanism for heat loss in sheep. Sweating also has some cooling effect mainly in shorn animals. Feed intake is reduced to minimize the heat production in body where as water intake increased. Rumination also slows down, respiration rate and respiratory volume increases
Regulation of body temperature in goats is much similar to that of sheep. Two major mechanisms to maintain body temperature in goats are increase in respiration rate and heat loss by evaporation. Horn of goat also supposed to play a minor role in maintenance of body temperature by its supply to brain. Goats are non sweating animals. Goats are more abundant in tropical and subtropical regions reflecting that they are more heat resistant in comparison to sheep. Jamnapari goat and Bikaneri sheep graze normally even at a high temperature of 47.80C, where as Corriedale breed of sheep requires artificial cooling at this temperature. Goats are prolific breeders in tropical region showing their well adaptation in these hot conditions. Water intake increases with rise in ambient temperature.
Thus we can say that both sheep and goat are well heat tolerant species and can be reared in tropical regions. When both species are compared in terms of heat tolerance goats has little bit edge over sheep.
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Rishi Kant1, R. P Diwakar2 and Pramod Kumar3
College of Veterinary Science & Animal Husbandry,
Achary Narendra Deva University Of Agriculture & Technology,Kumarganj
Ayodhya (UP)-224229 India
1 Assistant Professor, Department of Veterinary Pharmacology& Toxicology
2 Assistant Professor, Department of Veterinary Microbiology
3 Assistant Professor, Department of Veterinary Physiology& Biochemistry
REFERENCES:
Bligh, J. (1961). The synchronous discharge of apocrine sweat glands of the welsh mountain sheep. Nature(Lond.), 189,582-583.
Brockway, J.M., McDonald, J.D. and Pullar, J.D.(1963). Evaporative heat loss mechanisms in sheep. J. Pysiol., 179, 554-568.
Epstein, H. and Herz, A. (1964). Fertility and birth weights of goats in a subtropical environment. J. Agric. Sci.,62, 237-244.
