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多年来,人们普遍认为反刍家畜不需要补充B族维生素,因为反刍家畜瘤胃的维生物区系能合成多种维生素,满足机体需要。但目前的研究表明,反刍家畜仍需要对B族维生素的补充,因为反刍家畜的瘤胃微生物不能合成所有的维生素;并且还受以下 相似文献
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<正> 饲料的加工方法,对饲料性能的影响,随着家畜的种类及其生产类型的不同而不同。反刍动物饲料和单胃动物饲料,在加工的目的和方法上有很大不同,而在反刍家畜的范围内,肉用家畜和牛用家畜饲料的加工目的和方法也不尽相同。下面就反刍家畜饲料加工方法的共同点,肉用反刍家畜饲料和牛用反刍家畜饲料加工方法的不同点进行比较详细的叙述。 相似文献
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《中国牛业科学》2017,(6)
朊蛋白基因(PRNP)不仅与动物传染性海绵样脑病(TSEs)密切相关,还与反刍家畜的表型性状密切相关。已有研究表明:牛、水牛、牦牛、绵羊、山羊等反刍家畜PRNP基因具有丰富的多态性,同时,这些遗传变异位点在这些物种中又具有显著差异性;其中,牛、绵羊和山羊PRNP基因多态性与BSE、瘙痒病显著相关;牛、绵羊和山羊PRNP基因多态性与生产性能有密切相关性。为此,本文从反刍家畜PRNP基因结构比较、反刍家畜PRNP基因多态性研究、反刍家畜PRNP多态性与疾病的关系、反刍家畜PRNP多态性与生产性能的关系等四方面进行综述,以期为反刍家畜优良个体及品种的高效选育提供理论参考。 相似文献
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由于对反刍家畜消化代谢生理生化过程的不断认识,对于反刍家畜粗蛋白质利用研究不断深化,畜收工作者在反刍家畜饲养中已经开始利用粗蛋白质(包括非蛋白氮)来代替真蛋白质,从中取得可观的经济效益。本文仅就如何利用粗蛋白质,特别是尿素等非蛋白氮作为反刍家畜的蛋白质补充料的有关问题加以浅述。 相似文献
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肠道甲烷是反刍家畜瘤胃发酵的副产物,肠道甲烷排放降低了家畜对饲草料的利用率,同时是影响气候变化的重要因素。百年尺度上,CH_4全球增温潜势(Global warming potentials)是CO_2的25倍;20年尺度上,CH_4全球增温潜势是CO_2的72倍,CH_4对全球温室效应贡献率高达18%。反刍家畜瘤胃肠道是主要的CH_4排放源,实现反刍家畜CH_4减排对提高家畜生产能力和改善大气环境具有双赢效果。论文概述了反刍家畜肠道CH_4排放机制,家畜肠道CH_4排放趋势及反刍家畜肠道CH_4减排,以期为低碳牧业提供理论参考。 相似文献
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反刍家畜具有复胃,特别是较大容量的瘤胃,这是与单胃家畜有区别的显著标志。由于瘤胃中含有大量的微生物,因此反刍家畜在饲料利用和营养物质消化代谢方面与单胃家畜存在显著差异。近几10年来,国内外对反刍家畜营养学特点、瘤胃及其内容物评定饲料营养价值、非常规饲料的利用和人工瘤胃饲料的研究方面,做了大量的工作。现简述如下:一、反刍家畜瘤胃的消化特点对饲料营养物质消化代谢有较大影响的 相似文献
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一、适当补充蛋氨酸和赖氨酸同单胃家畜相类似,反刍家畜也有最基本的养分和必需氨基酸(EAA)需要量,然而,由于瘤胃微生物具有蛋白质转化器作用,反刍家畜的EAA营养不象单胃家畜那样明显。Candler等(1971)指出,当反刍家畜生产水平很高时,对添加蛋氨酸羟基类似物(MHA)的响应最大,Brette(1974)也指 相似文献
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利用芳香族化合物估测反刍动物采食量的潜力 总被引：14，自引：8，他引：6
综述了芳香族化合物的发现过程、反刍动物饲草料、瘤胃和尿液中芳香族化合物的主要类型及存在形式.马尿酸是最早从家畜排泄物中发现的芳香族化合物.反刍动物的尿液中排出的苯甲酸几乎完全来源于日粮中的前体物.饲料日粮中芳香族化合物是酚酸、简单酚、香豆素、棉子酚、酚的生物碱、类黄酮、单宁酸和木质素.羟基肉桂酸和安息香酸是维管束植物中广泛存在的一类酚类化合物,其在禾本科牧草中的含量远高于豆科牧草,但禾谷类籽实中的含量却很低.瘤胃液和尿液中的芳香族代谢物主要是无酚的芳香酸、酚酸和苯酚,环己烷羧酸是惟一发现的脂环族酸.饲喂不同的日粮饲草料,反刍家畜以马尿酸形式排出的氮量大约占尿氮总量的6%,变化范围为1%～38%.测定尿中芳香族化合物特别是马尿酸对预测反刍家畜的采食量具有重要潜力和作用. 相似文献
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We provide first an overview of studies on ruminant livestock that emphasises an inter-individual variability and a relative intra-individual consistency in fear responsiveness. Then, we provide evidence that genetic factors underlie fear responsiveness. We discuss problems that may hinder the genetic evaluation and the application of fearfulness traits for genetic selection in livestock. These problems include the absence of validation in experimental designs, the complexity of fear-related responses, and the interaction between genetic factors and environmental influences that limit the consistency in fear-related responses. Some possible welfare consequences of current selection programs are also considered. Finally, we discuss the possibility for including fear criteria in current selection programs and consider how such approaches may have considerable promise in ruminant livestock. More particularly, we outline current knowledge about how genes control fearfulness. Even if fear-related responses in ruminant livestock are complex, the capacity to select on fear-related criteria or even perhaps on genes that confer fearfulness traits has the potential to significantly enhance our ability to optimise livestock for their production environment and reduce the potential for compromise to their welfare. 相似文献
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Beigh Yasir Afzal Ganai Abdul Majeed Rather Mohammad Ashraf Athar Hakim Hamdani Shabeer Ahmad 《Tropical animal health and production》2020,52(5):2469-2480
Tropical Animal Health and Production - Assessment of the ruminant livestock feed sources availability, existing feeding practices, and nutrient balances was embarked at different zones of Gurez... 相似文献
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Methane (CH4 ) is the second most important greenhouse gas (GHG) and that emitted from enteric fermentation in livestock is the single largest source of emissions in Japan. Many factors influence ruminant CH4 production, including level of intake, type and quality of feeds and environmental temperature. The objectives of this review are to identify the factors affecting CH4 production in ruminants, to examine technologies for the mitigation of CH4 emissions from ruminants, and to identify areas requiring further research. The following equation for CH4 prediction was formulated using only dry matter intake (DMI) and has been adopted in Japan to estimate emissions from ruminant livestock for the National GHG Inventory Report: Y = −17.766 + 42.793X − 0.849X2 , where Y is CH4 production (L/day) and X is DMI (kg/day). Technologies for the mitigation of CH4 emissions from ruminants include increasing productivity by improving nutritional management, the manipulation of ruminal fermentation by changing feed composition, the addition of CH4 inhibitors, and defaunation. Considering the importance of ruminant livestock, it is essential to establish economically feasible ways of reducing ruminant CH4 production while improving productivity; it is therefore critical to conduct a full system analysis to select the best combination of approaches or new technologies to be applied under long-term field conditions. 相似文献
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Waller PJ 《Animal health research reviews / Conference of Research Workers in Animal Diseases》2003,4(1):35-43
Effective, sustainable control of nematode parasites of grazing livestock is becoming evermore challenging and difficult. This is largely due to two contrasting issues. One is the rapid escalation of resistance to anthelmintic drugs, which is arguably the greatest problem now facing the small ruminant industries worldwide. Secondly, there is the increasing trend towards organic farming, in which there is prohibition of the prophylactic use of all chemical compounds. Livestock producers urgently need non-chemotherapeutic alternatives in parasite control. Researchers have responded to this challenge and a variety of quite different approaches have been the subject of intense investigation in many countries for several decades now. These vary in relation to their stage of development for on-farm use, their utility, and their applicability across the spectrum of grazing livestock enterprises throughout the world. One relatively recent innovation is the biological control approach to nematode parasites. This has now reached the stage of commercialization. This review focuses on these issues and provides an overview of the possible ways in which the biological control of nematode parasites could be employed in grazing ruminant livestock systems worldwide. 相似文献
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Roberto Cortinas Carl J Jones 《Veterinary Clinics of North America: Food Animal Practice》2006,22(3):673-693
Arthropod ectoparasites are the most ubiquitous life forms affecting ruminant animals and commonly affect the daily activity and health status of ruminants. This article describes the phenology of several important ectoparasites of livestock and small ruminants, and delineates some general control and management strategies for protecting domestic ruminants. 相似文献
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The second in this series of clinical reviews on neurological diseases in ruminant livestock in Australia examines toxic disorders associated with plant and microbial toxins as well as the neurological effects of vitamin and mineral deficiencies. The aim of these reviews is to assist in the surveillance of neurological diseases, especially the transmissible spongiform encephalopathies. 相似文献
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The factors that control the demography of European hare Lepus europaeus populations are poorly understood, but it has been recognized that the decline of hares in Europe is associated with an increasing intensity of agricultural activity. Many mechanisms have been suggested. We propose another mechanism; a negative impact arising from ingestion of the infective larvae of ruminant livestock. We dosed juvenile hares from a worm-free colony with a conservative dose from a mixed culture of infective larvae of the nematode parasites of sheep and cattle. We examined the hares post-mortem for the establishment of those ruminant nematodes, differences in weight changes, and the shedding of eggs. 相似文献