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1.
不同放牧强度下绵羊采食方式的变化特征   总被引:5,自引:2,他引:5  
本研究将绵羊对禾本科植物的采食方式主要分为摘叶、拔芯和去顶3种类型.研究发现采食方式受植物种类、季节和放牧压的影响.对羊草(Leymus chinensis)的采食方式以去顶和摘叶为主, 对芦苇(Phragmites communis)的采食方式以去顶和拔芯为主.具体表现为,羊草的去顶率,8月以前随放牧强度减小、季节推移而降低,8月后则相反;摘叶率随放牧压增加和时间推移大致是先增加后减少;拔芯率随放牧压的增加而增大,6月最高,9月最低;总体上,未被采食的羊草比例随放牧压降低而增大,在生长季后期相应增加.芦苇去顶率随时间推移先降低后增加;拔芯率在6月随放牧压减小而降低,其它月份里主要随放牧压减小而升高,从整个生长季看,芦苇拔芯率在6月初最大;芦苇摘叶率的变化受前2种采食方式制约;未被采食的芦苇比例随放牧压降低而增加,但在7月后中牧要比轻牧和重牧低,在放牧干扰下,生长季里未被采食的芦苇比例在8月达最大.  相似文献   

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小反刍兽疫是由小反刍兽疫病毒引起的急性、烈性、高度传染性疾病,是WOAH法定报告动物疫病,对全球的畜牧业造成了严重的损失。FAO和WOAH联合制定了小反刍兽疫全球控制与根除战略。本文对小反刍兽疫全球控制与根除战略的内容和可行性进行了解读,并对我国小反刍兽疫防控情况进行分析,以期为我国小反刍兽疫的控制与根除提供参考。  相似文献   

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Peste des petits ruminants (PPR) is an acute, febrile, highly contagious and economically important viral disease of small ruminants. A polyclonal antibody based indirect ELISA was developed for detection of antibodies to PPR virus in the serum samples of goats and sheep using purified PPR viral antigen propogated in Vero cell culture. A threshold (cut-off) value was set as twice the mean of the negative population based on the distribution of known negative serum samples in respect of PPR virus antibodies in the test. A total of 1544 serum samples from goats and sheep were screened by indirect ELISA and competitive ELISA. The indirect ELISA compared very well with competitive ELISA, with a high degree of specificity (95.09%) and sensitivity (90.81%). When compared with virus neutralization test, the present assay had 100% specificity and 80% sensitivity. With serum samples, the assay could clearly differentiate animals from the infected population from uninfected ones. These results suggest that the indirect ELISA may be a good alternative tool to competitive ELISA for seroepidemiological surveys.  相似文献   

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We studied Kirdi goats and Foulbe sheep kept on-station at the Institute of Agricultural Research for Development (IRAD), Garoua to look at their immunological response following vaccination with a specific peste des petits ruminant (PPR) virus vaccine. Pre-vaccination PPR antibody seroprevalences were 44 and 29% in goats and sheep, respectively. Seroprevalences following vaccination were 100% in both species. Titres remained above the protection threshold level (1:10) in both species at 12 months. Maternal antibodies in young animals were detectable to up to 6 months of age but fell below the protection threshold level at 3.5 and 4.5 months in lambs and kids, respectively. Kids and lambs from immunised or exposed dams should be vaccinated at 4 and 5 months of age, respectively.  相似文献   

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发展反刍动物绿色营养技术   总被引:16,自引:0,他引:16  
作者把以提高反刍动物对日粮营养物质的利用率和减少对环境污染为目标的一整套实用的营养技术称之为反刍动物绿色营养技术。本文从提高氮代谢利用率、提高日粮能量利用率和提高日粮矿物质元素利用率三个方面介绍了国际上在这些方面的研究进展和技术进步 ,并着重介绍了内蒙古畜牧科学院近年来在发展反刍动物绿色营养技术方面的研究成果。本文介绍的反刍动物绿色营养技术措施有以下九种 :(1)饲料蛋白质保护和尿素缓释技术 ;(2)激素调控氮代谢技术 ;(3)进入小肠食糜氨基酸平衡技术 ;(4)降低甲烷发散技术 ;(5)日粮营养结构平衡调控技术(利用代谢葡萄糖调控组织代谢层次C3+C6 能占ME摄入量比值技术) ;(6)提高低质粗饲料的营养工程技术 ;(7)使用矿物质螯合物或络合物技术 ;(8)日粮阴阳离子平衡技术 ;(9)控制磷的排放技术。作者着重指出 ,在设计和使用这些技术时 ,应强调围绕一定的调控目标 ,将多种营养技术措施加以系统组合 ,充分利用其正组合效应 ,尽量控制或缩小其负组合效应 ,以达到充分发挥各种营养技术措施整体优势的目的。  相似文献   

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The potential of tannins from 21 medicinal and aromatic plant leaves as antimethanogenic additives in ruminant feeds was investigated. The effect of tannin from these leaves on rumen fermentation parameters, protozoa population and methanogenesis was studied by incubating the samples [200 mg dry matter (DM)] without and with polyethylene glycol (PEG)‐6000 (400 mg DM) as a tannin binder during 24‐h incubation in the in vitro Hohenheim gas method. Based on the methane percentage estimated in the total gas produced, methane production in millilitre was calculated [methane volume (ml) = methane % × total gas produced (ml) in 24 h]. In the samples, crude protein and neutral detergent fibre (g/kg DM) ranged from 113 to 172 and from 352 to 444 respectively. The total phenol (TP; g/kg DM) content was highest in Terminalia chebula (274) followed by Hemigraphis colorata (71) and Sapindus laurifolia (51) respectively. In the remaining samples, it was <43 g/kg DM. Activity of tannins, as represented by the increase in gas volume on addition of PEG, ranged from 0 to 133%, with the highest being recorded in T. chebula. The per cent increase in methane on PEG addition was 0 for Ammi majus, Aristolochia indica, Cascabela thevetia, Ipomea nil and Lantana camara, illustrating that tannins present in these samples had no effect on methane concentration. The PEG addition increased the total protozoa count by >50% in A. indica and C. thevetica. One of the important findings of our study was that of the 21 samples screened, Entodinia population increased in 12 with PEG as compared to 7 where Holotricha increased, indicating higher susceptibility of Entodinia to tannin. There was no increase in the protozoa population with PEG when incubating Cardiospermum halicacabum, Clerodendrum inerme, Dioscorea floribunda, Nerium oleander and Selastras paniculatus, which strongly suggested that methane suppression recorded in these samples was not because of a defaunating effect of their tannins per se. The fermentation pattern reflected increased total volatile fatty acid (TVFA) concentration from 0 to 28.3% with PEG addition among the leaves. Our results confirmed further observations that methanogenesis in vitro is not essentially related to density of protozoa population. Secondly, medicinal and aromatic plants such as C. inerme, Gymnema sylvestre and Sapindus laurifolia containing tannins appear to have a potential to suppress in vitro methanogenesis.  相似文献   

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尿素在青贮饲料中的应用   总被引:1,自引:0,他引:1  
在描述反刍动物利用尿素机理的基础上,介绍了尿素青贮的作用、青贮饲料中的尿素用量、尿素青贮对青贮成分的影响以及尿素青贮对家畜生产性能的影响,并进一步指出了存在的问题。  相似文献   

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铜作为反刍动物营养中重要的微量元素之一,对反刍动物的生命活动有着重要的作用。文章主要综述了微量元素铜对反刍动物的营养生理作用、铜在反刍动物生产中的应用和反刍动物铜缺乏的危害,并提出了反刍动物铜缺乏的预防措施。  相似文献   

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反刍动物瘤胃和粪便中产生的甲烷是造成大气温室效应的主要气体之一。但是,粪便中甲烷排放持续期很长,排放数量难以检测,故受到研究者的忽视。作者介绍了反刍动物粪便中甲烷排放量的测定技术,探讨了其排放量的影响因素,指出有必要同时研究瘤胃和粪便中甲烷生成的调控措施。  相似文献   

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This study was initiated to determine whether a comparative pharmacokinetic (PK) approach could be used to expand the pool of approved anthelmintics for minor ruminant species. Accordingly, the PK profiles of six anthelmintics (levamisole, albendazole, fenbendazole, moxidectin, doramectin, and ivermectin) in sheep, goats, and cattle were determined. The PK values determined for each anthelmintic included Tmax, Tlast, Cmax, AUC, AUC/dose, and Cmax/dose. The results of this study demonstrate that a comparative PK approach does not show commonality in the way these six anthelmintics are individually processed by these three ruminants. While some drugs demonstrated identical PK profiles between sheep and goats, none of these drugs demonstrated PK profiles in sheep and goats comparable to the PK profiles found in cattle. The results from this study suggest drug approval across these three ruminants is not a viable concept. However, the resulting PK profiles for each combination of drug and ruminant species represents a new dataset that can be used to support the US FDA Center for Veterinary Medicine's Minor Use/Minor Species indexing process for drug approvals in minor species such as sheep and goats.  相似文献   

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小反刍兽疫是一种传染性极强的病毒性疾病,主要影响家养及野生的小反刍动物。该病的主要特征是发热、口腔炎、结膜炎、肠胃炎和肺炎,是世界动物卫生组织(World Organization for Animal Health,OIE)规定必须上报的疾病之一。文章对该病的流行与传播、诊断方法及防控措施进行了综述。  相似文献   

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小反刍兽疫是一种传染性极强的病毒性疾病,主要影响家养以及野生的小反刍动物。该病的主要特征是发热、口腔炎、结膜炎、肠胃炎和肺炎。小反刍兽疫也是世界动物卫生组织(0IE)规定必须上报的法定疾病之一。文章对该病的流行、传播方式、诊断方法以及防控措施进行了综述。  相似文献   

18.
The ruminant urinary tract is normally obscured by abdominal viscera, which hampers rediographic investigation by conventional urographic methods. A double contrast technique that uses pneumoperitoneum in conjunction with excretory urography is described. Bolus and infusion urographic techniques were used in sheep and calves. Only the infusion technique was used in cows. The radiographic anatomy of the upper urinary tract in these animals is described. Visualization of the nephrogram and collecting system varied, depending on the method of excretory urography used.  相似文献   

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本文简要介绍了益生素对反刍动物的影响及作用机理,并对有待于继续研究的问题进行了探讨。  相似文献   

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小反刍兽疫(PPR)是一种主要感染山羊和绵羊的传染病,病原为副黏病毒科麻疹病毒属的小反刍兽疫病毒(PPRV).PPRV基因组由6个基因组成,依据N和F基因可将PPRV分为4个谱系或者基因群,我国流行的PPRV属于谱系Ⅳ.2007年我国首次报道发生PPR疫情,在2014年大流行后,农业农村部加强了 PPR的防疫措施.目前...  相似文献   

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