javad Motamedi(torkan); Hossein Arzani; Mehdi Ghorbani
Abstract
More than 20 sheep breeds having different body size utilize various rangelands in different climate regions which the conversion coefficient of each breed compared to animal unit must be recognized. For this purpose, two herds were selected from each breed sheep grazing at the central region during ...
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More than 20 sheep breeds having different body size utilize various rangelands in different climate regions which the conversion coefficient of each breed compared to animal unit must be recognized. For this purpose, two herds were selected from each breed sheep grazing at the central region during 2001-2007. Among selected herds, 30 animals randomly weighted at various age and sex groups and at various grazing seasons. Mean weight of three and four years old sheep was considered as mature weight of each breed. Conversion coefficient of each breed to animal unit (animal unit equivalent) calculated from the ratio of metabolic weight ((live weight)0.75 to animal unit metabolic weight. According to the results, Naeeini breed classified as light body breeds, Zandi, Kermani and Varamini as medium body and Shaal as heavy body breeds. Equivalent animal unit for each breed to animal unit were 0.7, 0.86, 0.9, 0.97, 1.06 and 1.20. based on proposed conversion coefficient and using MAFF proposed equation, daily requirement of each breed at maintenance condition and at grazing condition were as 4.76, 5.85, 6.12, 6.60, 7.21 and 8.16 MJ per day. Results represent that considering to same forage amount as daily requirement of grazing sheep breed in rangelands in order to calculating grazing capacity, without considering their body size is not valid.
H. Arzani; A. Esfandiari; H. Nourozian; M. Ghorbani; J. Torkan
Volume 62, Issue 2 , October 2009, , Pages 175-186
Abstract
Knowledge on animal requirement, available forage and its quality is fundamental for successful livestock and range management. Since sheep is dominant grazing animal of rangelands in Iran and there are over 27 sheep breeds and each breed has special body size, physiological condition and consequently ...
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Knowledge on animal requirement, available forage and its quality is fundamental for successful livestock and range management. Since sheep is dominant grazing animal of rangelands in Iran and there are over 27 sheep breeds and each breed has special body size, physiological condition and consequently different daily nutrition requirement, animal unit should be determinated for dominant breed of sheep in every region to be calculated the forage requirement based on body weight, daily energy requirement and quality of available forage. In this study, two herds of Kermanshah's Sanjabi breed have been weighted including 50 animals in each herd (15 heads three years old ewe, 15 heads four years old ewe, 5 heads three years old ram, 5 heads four years old ram, 5 heads three months old lamb and 5 heads six months old lamb) in three stages. The body weight of Sanjabi breed (based on average body weight of three and four years old ewe) was 60.68 ±0.56 kg. Animal unit equivalent (AUE) for ewe, ram and lamb were 1.29, 1.88 and 0.63 kg, respectively. The results of analysis of variance indicated that there are significant differences between weight of ewes and rams (P