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从动物机体和机体与环境两大系统出发,对影响我国放牧绵羊生产性能的主要营养因素进行了深入探讨,提出了蛋白质、可发酵能和某些矿物质元素缺乏是我国北方放牧绵羊的限制性营养因素,最后提出进一步提高我国放牧绵羊生产水平的一些关键措施. 相似文献
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影响我国放牧绵羊生产性能营养因素的探讨 《畜牧与饲料科学》1997,18(Z1):120-120
从动物机体和机体与环境两大系统出发,对影响我国放牧绵羊生产性能的主要营养因素进行了深入探讨,提出了蛋白质、可发酵能和某些矿物质元素缺乏是我国北方放牧绵羊的限制性营养因素,最后提出进一步提高我国放牧绵羊生产水平的一些关键措施。 相似文献
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人工草地绵羊放牧系统研究—载畜量试验 总被引：3，自引：0，他引：3
通过监测划区轮物条件下的放牧系统中两种载畜量的牧草生长速度，草地现存量，绵羊采食量以及绵羊生产性能等有关指标的动态变化，探讨了高低两种载畜量对系统中牧草生长，草地利用和家畜生长三方面的影响。结果表明：低载畜量仅在羊毛产量，羔羊断奶及半岁体重等三项指标上显示出一定，它方面均无显著差异。草畜平衡分析结果表明，在本试验采用的两种载畜量下，系统中牧草全年供给量均大于家畜需求量，说明系统还有潜在生产能力。 相似文献
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澳大利亚联邦科学与工业研究组织家畜生产部的科学家们研制出一种称为“蠕动泵”的装置,以此提供放牧绵羊营养方面的内部资料。众所周知,放牧绵羊的采食情况和营养需要与舍饲绵羊大不相同。使用这种蠕动泵可测出放牧绵羊从牠所食 相似文献
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本试验自1982～1985用山羊、绵羊及牛三种家畜重牧(100公斤代谢体重/0.4公顷)来清除美国东北部撂荒地灌木。结果表明:放牧一年后,放牧山羊小区内灌木下降50％,两年后,基本消失,而禾草旺盛生长(增加45％)、豆科牧草比重增加;放牧绵羊及牛的小区第一年没有变化,两年后比重有所下降。三种家畜清除灌木的效果是:山羊>绵羊>牛,在灌木、禾草及杂类草共生草地中,三种家畜混牧,山羊不仅不与二者争食,而且有利于清除灌木,具有互补作用。 相似文献
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高山草原绵羊放牧生态及消化代谢系列研究 总被引：9，自引：2，他引：7
应用灰色系统理论中的灰色关联度分析法对影响高山草原牧草营养的季节性与放牧绵羊消化代谢和生产性能动态关系的18种主要限制性因素进行了研究。关联度分析结果表明：牧草代谢能浓度是影响放牧绵羊采食量的主要因素；影响放牧绵羊日增重的主要因素是大气温度和饲养粗蛋白质含量；羊毛生长速度限制性因素是饲草粗蛋白质水平，气温对羊毛的生长速度影响较小；瘤胃氨氮量是影响粗蛋白质存留率的主要因素，气温影响次之。 相似文献
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本文以不同水平人工草地绵羊放牧系统的监测分析资料为基础，针对原系统中存在的问题，提出了系统优化方案。 相似文献
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产羔期、补饲水平对考力代羊生产和繁殖性能影响的研究 总被引：2，自引：1，他引：1
为了研究草地一绵羊系统中草畜供求间的动态平衡，寻求在人工草地放牧条件下适宜的产羔时期及在此时期给产羔母羊的合理补饲水平，１９９０～１９９３年，在贵州省威宁县灼甫联户示范牧场进行了两期产羔期及补饲水平对绵羊生产性能影响的试验。产羔期的改变，导致了母羊及羔羊体重的不同变化趋势。结果显示出母羊体重对其生产、繁殖性能的重要性。春羔母羊配种前体重较之冬羔母羊提高９．７５ｋｇ，两者产羔率分别为１３９．２％和１１６．１％。春羔母羊较高的双羔率导致了春羔母羊较之冬羔母羊更低的繁殖成活率（分别为９１．２％和１０４．７％）。断奶时，春羔较之冬羔体重高５．２５ｋｇ，但断奶以后这种优势即消失了。补饲水平的差异对母羊及羔羊体重有一定的影响，但在牧草丰富的条件下表现得并不很强烈。 相似文献
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为了探讨优良地方品种滩羊最佳产羔季节,从生产发育、羔羊成活率和经济效益3个方面进行研究试验结果表明,试验组羔羊平均初生重3．66kg,1月龄体重8．80kg,3月龄体重16．78kg;对照组羔羊平均初生重3．42kg,1月龄体重9．60kg,3月龄体重18．25kg。冬羔初生重大于春羔,而断奶期生长速度低于春羔。冬羔的成活率为97．5％,春羔为95．8％。3月龄冬羔每只收入402．72元,春羔每只收入401．5元。春羔虽然断奶期日增重高于冬羔,但综合羔羊成活率、经济效益等因素,在甘肃省景泰县饲养优良绵羊品种滩羊冬羔的生产效果和经济效益优于春羔。 相似文献
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中国北方草原草畜代谢能平衡分析与对策研究 总被引：2，自引：0，他引：2
草畜平衡是天然草地可持续利用和放牧家畜高效生产的前提,草畜平衡评估技术是实现草原保护,提高草地畜牧业可持续发展的基础。本研究建立了以代谢能为指标的草畜平衡评价方法,２００８年冬以甘肃肃南草原和典型牧户为研究对象,通过草畜代谢能平衡分析了草畜平衡现状,应用研究试验,验证了实现草畜平衡的优化途径和对策。草畜平衡分析结果表明,在牧草生长期（６月－１０月）家畜获得的代谢能高于家畜的维持需要,因此,家畜体重增加,生长速度最快;在枯草期（１１月－次年５月）代谢能摄入量低于维持需要量,家畜掉膘,体重下降,夏草场的载畜量最大。冬季暖棚舍饲养殖能够降低家畜的代谢能需要,有助于实现草畜平衡。与对照组相比,暖棚养殖绵羊平均产毛量显著提高（P＜０．０５）,提高了０．７３ｋｇ／只,冷季体重损失减少１４．９％,纯收入增加１２６．２５元／只。产羔时间对草畜平衡具显著的影响,适当推迟产羔时间能够有效的改善草畜平衡状况。分别测定了４月和５月所产羔羊的生长发育情况和母羊体况,５月羔羊平均初生重、１月龄、２月龄体重显著高于４月份羔羊（P＜０．０５）,但由于生长期短,５月羔羊出栏重较４月低４～５ｋｇ。草畜代谢能平衡是分析研究草畜平衡的科学、合理和准确的方法和技术,草畜代谢能平衡分析模型的准确度高,适用性强,有利于草原管理,所提出的改善草畜平衡的途径和策略可
行性高。 相似文献
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Campbell AJ Croser EL Milne ME Hodge PJ Webb Ware JK 《Australian veterinary journal》2012,90(6):235-239
Background Several outbreaks of goitre, considered to be related to iodine deficiency, occurred in sheep flocks throughout Victoria in 2010. Objective We describe one outbreak in Merino–Border Leicester‐cross ewes and their lambs in north‐east Victoria that appeared to be associated with increased rainfall and pasture growth, particularly during the preceding summer and autumn. Results The outbreak was characterised by a four‐fold increase in neonatal lamb deaths and goitre, alopecia and poor skeletal development in the lambs. Most cases occurred in lambs born to 2‐year‐old crossbred ewes that had grazed long, lush perennial pastures throughout their entire pregnancy, whereas few cases occurred in mature crossbred or Merino ewes that had grazed shorter, annual pastures on hill country for 3 weeks in late pregnancy but were otherwise managed similarly. Conclusion Existing recommendations for south‐eastern Australia are that only spring‐lambing ewes in iodine‐deficient areas require iodine supplementation to prevent goitre in years with high autumn–winter rainfall. Aspects of this outbreak suggest that ewes lambing at other times of the year and grazing abundant pasture for prolonged periods may also require supplementation to prevent goitre, even if autumn–winter rainfall does not exceed previously established thresholds. 相似文献
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本试验采用引进优良肉用种公羊与藏羊进行经济杂交生产杂一代肉用羔羊,通过“放牧＋补饲”育肥技术,达到当年羔羊适时育肥出栏,加快羊群周转、增加收入,减轻冬春草场压力,保护草地生态和持续合理利用天然草场,提高养羊业经济效益,进一步增强优质羔羊肉市场竞争能力,促进海北州羔羊生产向可持续和产业化方向发展. 相似文献
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Egil Simensen Sigrun Hauge 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(3):120-126
A study of ewe performance was undertaken in 795 sheep flocks based on data from the Norwegian Sheep Recording System. Herd level data included in the annual report for 1998 were used as the basis for the study. Average flock size was 75.3 ewes. The material was considered as representative of the better and more motivated sheep farmers in the mountain valley regions in south-eastern Norway. The average number of lambs born per ewe, inclusive (and exclusive) of barren ewes, was 1.89 (2.02), and of autumn lambs (those surviving from birth in the spring to autumn) 1.60 (1.66). The average autumn weight of the lambs corrected to 145 days of age was 42.4 kg, giving an overall performance of 67.9 kg lambs live weight per ewe. When including artificially reared lambs, overall performance was 70.4 kg per ewe. Artificial rearing of lambs, mostly triplets which had been removed from the ewe, was practised on 395 of the farms. In the 74 flocks with a rate of artificial rearing of more than 10% of all lambs, overall performance per ewe was 13.3 kg higher than in flocks with no artificial rearing. Total lamb mortality from birth to autumn recording, including stillborn lambs, was 12.44%. Mortality had a skewed distribution, some flocks having very high mortality figures. The arithmetic means (and medians) for mortality were as follows: 2.75 (2.29)% stillbirths, 2.93 (2.30)% died during the indoor feeding period, 0.88 (0.00)% at spring pasture, and 6.16 (4.40)% at summer pasture. In regression models using Proc Genmod in SAS®, it was found that average number of autumn lambs per ewe was negatively associated with the rate of barren ewes, late lambing date (flock average day in year when lambing took place), and total lamb mortality. The corrected autumn weight of the lambs was positively associated with the average number of lambs born per ewe and non-fertility rate, and negatively associated with flock size and total lamb mortality. The Dala breed had a positive effect on number of autumn lambs per ewe, and Spæl breed a negative effect on corrected autumn live weight of the lambs. 相似文献
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Efficiency of Duddingtonia flagrans against Trichostrongyle infections of sheep on mountain pastures
The control of sheep nematode parasites in extensive mountain/transhumant management systems using the nematophagous fungus Duddingtonia flagrans was assessed in this study. Two groups of Churra Tensina ewes were allowed to graze for 8 weeks in autumn on two separate paddocks of infected pasture near their winter sheds in the valley. At lambing, ewes and their twin lambs were turned out into the same paddocks for the following 12 weeks. One group of ewes received a daily dose of 5 x 10(5) chlamydospores of Duddingtonia flagrans/kg live weight per day both in autumn and in spring, while the other group was used as a non-treated control. Daily dosing of grazing ewes with the fungus D. flagrans had a clear effect on reducing autumn pasture contamination. This had a subsequent effect on the over-wintering larvae population that was confirmed by a 20% lower worm burden of tracer lambs kept in early spring on the paddock previously grazed by fungus treated ewes. In spring, pasture contamination was also significantly reduced in the paddock grazed by fungi-treated ewes and their lambs showed a 61% lower worm burden and a better performance than the control lambs. Results herein show that fungal spores fed to sheep at critical times with regard to the epidemiology of parasite infection, can have a significant effect on the infective larvae present on pasture, which could further improve lambs performance. This novel approach to parasite control would be of interest amongst both organic and conventional sheep farmers operating in mountain regions. 相似文献
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Autopsies were performed on lamb carcases from 2 groups of Merino ewes lambing in paddocks in spring 1978 and from 1 group lambing in pens in 1980 in southwest Queensland. These showed that the main causes of death were starvation due to failure of the lamb to obtain milk, problems at parturition causing death during or shortly after birth and, in some cases, predation. The majority of lambs died within 1 week of birth with the highest mortalities occurring in the lighter lambs. In the pen study, mean birth weight of lambs that died was 3.0 (s.d. = +/- 0.5) kg. The mean daily weight loss of lambs that died of starvation in the pens was 0.22 kg and the mean loss to autopsy was 0.35 kg. In the pen study, there were more lamb deaths, deaths from starvation, mismothering and desertion in each of 2 groups fed a below maintenance ration than in an above maintenance group. More lambs died and more lamb deaths were due to starvation in a group with unsound udders than in a sound udder group. The results are similar to those found by workers investigating perinatal lamb mortality in other areas. Their significance is discussed in relation to Merino sheep flocks in southwestern Queensland. 相似文献
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人工草地绵羊放牧系统草畜供求关系的优化 总被引：9，自引：1，他引：9
在牧草平均生长量及其生长模式，基础母羊载畜量相同的前提下，以年生产周期为时间单元，以产羔时间的选择为主要手段，对人工划时绵羊放牧系统进行了逐步的总体优化设计和实验监测对比。逐步优化以后的产春盖设计系统与原产冬羔的生产系统相比，草畜供求的季节匹配趋于合理，全年供求趋于；上单位的冬季补饲成本可以由４．４６元下降到１２．０８元；草地产出利润可由７４５元／ｈｍ＾２提高到１４１３元／ｈｍ＾２。优化后的实验监 相似文献
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