Forage quality and daily requirement of grazing animal in the Nadoshan rangelands

Determing of daily metabolism energy required livestock rangelands in different climatic zone، in order to calculate grazing capacity is essential. In this regard; daily metabolism energy required in Balochi breed sheep and Nadoshan breed goat in Nadoshan rangelands were studied. For this purpose، according to the average values ​​of forage quality indices in plant species and their proportion in the composition of rangeland vegetation in different growth stages، metabolism energy value in 1Kg of dry matter for livestock grazing rangelands was estimated. Considering of daily metabolism energy required in Balochi breed sheep and Nadoshan breed goat، amount of forage which supplies animal requirements in different stages of growth in this region، were estimated. Daily requirement of sheep، ram and lambs of Balochi breed sheep and animal classes of Nadoshan breed goat based on metabolism energy، according to the MAFF equation proposed (1984) in the state of maintenance and livestock grazing in rangeland، and considering the physical characteristics of the rangelands، intervals of animal drinking places، plants density and 40% additive coefficient، were calculated 8. 19، 14. 66، 8. 29 and 5. 90، 6. 0، 5. 45 Mj، respectively. According to the results، amount of forage required to provide the daily requirements of sheep، ram and lamb of Balochi breed sheep considering the forage quality of rangelands in the initial stages of growth respectively، is 0. 92، 1. 64 and 0. 93; in the middle of stages growth respectively، is 1. 06، 1. 89 and 1. 07، and in the final stages of growth is 1. 19، 2. 13 and 1. 21 Kg of dry forage. Thus، the amount of forage required to provide the daily requirements animal classes of Nadoshan breed goat considering the forage quality of rangelands in the initial stages of growth is 0. 66، 0. 67 and 0. 61، respectively; in the middle of stages growth is 0. 76، 0. 77 and 0. 70، respectively and in the final stages of growth is 0. 86، 0. 87 and 0. 79 Kg of dry forage. This implies that time of grazing affects on the daily requirements of livestock and daily requirement of livestock must be determined according to forage quality. It is obvious that the quality of forage plants changes depending to the environmental condition of year، but since the determing forage quality is expensive، the obtained results can be used to estimate daily requirement of livestock in different years.