Manegement of sheep, goat and camel in arid and semi-arid regions for optimum and sustainable production of animal and range.

Английский. Human needs to animal products have been increased due to increasing population and changing diet habite. Sheep, goat and camel are adapted animals in arid and semi-arid regions. These animals depend more to rangelands for feed requirments as grazing animals. Rangelands have many benefits for society such as suppling forage, medicines, soil and water conservation, genetic resources, recreation and etc. Report of regional agensis and direct observations, indicated that rangelands have not expectable efficiency based on ecological condition and need proper management especially by considering animals as an integraded parts of range ecosystem. So, the aims of this investigation were to present some ways for managent of these animals through scientific approachs for sustainable production of ranglands and improving productivity of animals. Two management systems of private rangelands and non private rangeland measured for two years for forage production, condition and trend. In general private rangelands have better condition and trend relative to none private rangelands and produce about 15% more yied than none private range. In this system, the annual income of a sheep is about 115000 rials. Animals depend to about 50 to 60% of their feeds to rangelands. For improvement of the income of stockholders, agriculture also should be considered as part of these production system. Some species have shown good adaptability to arid and semi-arid environment and recommended for rangeland improvement. They are mentioned in the text...

Английский. ...Cultivating some species as pasture have promise for producing more forage for grazing animals. Cultivated pastures produced two times forage comparing to natural range in Sisab Research Station. Three grass species of Agropyron desertorum (Agd), Agropyron elengatum (Age) and Bromus tomentellus are have shown adaptability in semi-arid area. Because threre is less information about mangement of these grasses, this study was conducted in SRS in north of Iran to evaluate plant responses to grazing management. Three grazing intensities of light (20 to 45%), moderate (45- 65%) and heavy (65- 80%) of forage removal and without grazing applied by lamb and sheep for three consequent years from 1999 to 2001. The forth year considered as rest grazing. During this study, pastures experienced drought, normal and wet years (195 to 367 mm rainfall). Growing periods were recorded 110, 132 and 168 days for Brt, Agd and Age respectively. The averaged herbage mass (HM) productoion of Agd (1357 kg/ha) and Age (1250 kg/ha) across the years were statistically similar and higher than Brt (880 kg/ha). HM decreased by reduction in annual precipitation in all species especially in Age. It seems that that removal 45-65% of herbage mass annually or 20 -45% with one year rest after three years grazing is suitable for survival of these plants. Forage quality decreased through the grazing season. Animals have different grazing behavior and prefere species with different morphology and quality. So, sheep should be raised in north and sheep and goat in south of Khorasan. Camel can tolerate harsh condition of desert regions. Selection goal in sheep industry of Khorasan changed to meat production. So, the stock holders select high weight breeds. Performance of pure breeds of Kordian, Moghani and Chini ) was studied with 32 lambs of each breed under different grazing lands. Grazing management conducted in Bromus tomentellus, Agropyron desertorum and Agropyron elengatum, as grasses, Eurotia ceratoides, Kochia prostrata, and Salsola orientalis as halophytes , residual cereal crops and natural range without annual feeding. Animals weighted every 15 days. Data analysis with SAS software . Mean daily gain were 220, 180 and 160 (g/day) at grasses, 157, 139, 106 (g/day) at halophytes and residual cereal and 20 , 89 , 53 (g/day) at natural range in Kordian , Moghani and Chini lambs respectively. In another experiment daily weight gain of ewes also decreased over grazing season. Kordian and Chini ewes showed better performance than two other breeds under Sisab Research Station condition.Atriplex canscence is a plant in which extensively used for range reclamaain . This plant is not provide all feed requirment of animals as pure stand. To improve animal nutrition, and experiment conducted by feeding 20 male Bluchi Sheep with using diffent proportion of 0, 25, 50, 75 and 100 percent dry matter (DM) of Atriplex canescence (A.ca) and Panicom antidotal (P.an). Digestibillity of these rations measured as in-vivo method. Also Chemical composition of both plants were measured in laboratory. The data for Crude Protrin (CP) (%13.72 and %12.2), NDF (%32.75 and %62.03), ADF (%16.43 and %29.17) and energy (3720 and 3845 Kcal/kg) obtained for A.ca and P.an. repcctively.Using mixed rations both plants with proportions of 75:25 and 50:50 showed the same results for DM, orgnic matter (OM), CP, crude Energy, NDF and ADF but when data corrected as metubolic weight, using 50:50 percent of each species in feed ration, gave better results for sheep nutrition improvement. An experiment was conducted in examine the effect of supplemental feeding (SF: 250g of barley/day) on production and reproduction efficiency of 105 Balouchi ewes. Treatments were: 1) no SF, 2) SF from one month before mating to weaning 3) SF from mating to weaning 4) SF from one month before lamb weaning 5) SF from lambing to weaning. Ewes were mated with rams at the same time by sider. The pregnant ewes weighted monthly, ٧٠weaning weight and daily weight gain of lambs were also recorded. Data were analyzed based on imbalanced complete randomized design and means were compared by Duncan test. Milk production, weight before lambing, daily loosing weight during the first month of postpartum were not different between treatments. But wool production, weight after lambing, 30d weight of lamb and the weight of ewes at the end of the experiment were affected (p0.05) by SF. SF had significant (p0.05) effect on 30d weight, weaning weight and daily weight gain of lambs but it had no effect on the birth weight. Results showed that using of barley as an energy source may prevent from culling and improve the weight of ewes at the end of experiment which in turn result in increased longevity, production and reproduction efficiency in following parities. On the other hand supplemental feeding increased birth and weaning weights of lambs.