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1.
粗饲料是反刍动物最主要的饲料来源,而粗饲料中的各种纤维物质不能被宿主动物直接利用,而是先通过瘤胃内微生物的发酵形成挥发性脂肪酸(VFA)后才能被宿主动物作为能源物质吸收利用。某些粗饲料原料由于质地粗硬、适口性差,导致反刍动物对其利用率降低,造成生产效率低下。从改善饲料纤维物质的营养特性及提高瘤胃微生物降解纤维物质的能力两个角度出发,对如何提高饲料纤维物质在瘤胃内的降解率作一介绍。  相似文献   

2.
粗饲料是反刍动物最主要的饲料来源,而粗饲料中的各种纤维物质不能被宿主动物直接利用,而是先通过瘤胃内微生物的发酵形成挥发性脂肪酸(VFA)后才能被宿主动物作为能源物质吸收利用.某些粗饲料原料由于质地粗硬、适口性差,导致反刍动物对其利用率降低,造成生产效率低下.从改善饲料纤维物质的营养特性及提高瘤胃微生物降解纤维物质的能力两个角度出发,对如何提高饲料纤维物质在瘤胃内的降解率作一介绍.  相似文献   

3.
反刍动物瘤胃纤维降解微生物能分泌大量的纤维素酶和半纤维素酶,在瘤胃纤维降解过程中发挥着重要作用,是反刍动物高效利用粗饲料资源的基础。该文简要介绍了纤维素酶组成、瘤胃纤维素酶基因多样性研究进展,综述了纤维素酶降解纤维素的作用机制以及厌氧真菌对纤维物质的降解过程,概述了近年来瘤胃纤维降解微生物的分离筛选研究进展,以及碳水化合物、饲料加工和添加剂对瘤胃纤维降解微生物的调控作用,以期为相关研究提供参考。  相似文献   

4.
设计奶畜日粮的饲料营养学要点   总被引:3,自引:0,他引:3  
充分发挥瘤胃微生物消化粗饲料和利用 NPN等的有益功能,并尽量避免微生物对高品质饲料的降解损失,保持瘤胃微生物与反刍动物本身消化代谢活动的协调统一,是设计奶畜日粮的基本出发点。该文从奶畜日粮结构、不同生产水平时日粮蛋白质来源、精粗饲料的饲喂状态、高效添加剂的选用等方面论述设计奶畜日粮的饲料营养学要点。  相似文献   

5.
瘤胃纤维分解菌多纤维素酶体及其类似物的研究进展   总被引:3,自引:0,他引:3  
反刍动物瘤胃微生物能够有效地降解粗饲料,瘤胃细菌特别是纤维分解菌在此过程发挥了特别重要的作用。近年来的研究表明,只有与饲料颗粒相黏附的细菌才直接负责纤维物质的降解,可见黏附是瘤胃细菌降解纤维物质的关键步骤。多纤维素酶体是某些厌氧细菌和真菌产生的、能使微生物细胞与纤维物质发生黏附并高效降解纤维物质的多酶复合体。本文综述了多纤维素酶体的分子结构、瘤胃中主要纤维分解菌的多纤维素酶体及其类似物等方面的研究进展。  相似文献   

6.
提高反刍动物瘤胃的纤维降解率是增加粗饲料利用的有效途径.本文从饲料纤维对反刍动物采食量、咀嚼和反刍,对瘤胃发酵的调控以及对消化、生产性能和健康的影响三个方面综述了饲料纤维的营养调控作用.  相似文献   

7.
国际饲料分类法与我国饲料分类方法均将饲料中自然含水量低于45%,粗纤维高于18%的饲料划为粗饲料,包括青绿饲料制得的干草(粉)、脱谷收得农副产品(秸杆、秕壳等)以及糟渣类、饼粕产物、草籽、油料籽实等饲料。这类饲料一般营养价值相对低,其主要利用者为反刍动物,利用的关键在于瘤胃微生物对粗饲料的摄取、消化、降解的能力。研究反刍动物瘤胃微生物对粗饲料的摄取、消化、降解的机理以提高反刍动物粗饲料的利用效率一直是饲料科学和相关领域十分关注的课题。  相似文献   

8.
瘤胃是反刍动物最主要的消化器官,寄养着细菌、真菌、原虫、古生菌等多种微生物,这些瘤胃微生物菌群在反刍动物消化系统中起着重要作用。瘤胃真菌在瘤胃微生物中占比较小,且绝大多数为厌氧真菌。瘤胃真菌可以充分降解纤维物质,同时真菌还参与蛋白质和淀粉的降解过程,以提高饲料的利用率。瘤胃真菌的数量容易受硫元素、氮元素以及瘤胃内其他微生物的影响,因而从这些方面对饲粮进行调控,能够提高瘤胃内真菌的数量,从而提高反刍动物的消化能力和对饲料的利用。文章结合国内外研究进展,从瘤胃真菌特点、功能、影响因素及应用等多个方面进行综述,以期为反刍动物的健康养殖提供参考。  相似文献   

9.
毕晋明 《饲料工业》2006,27(7):39-41
瘤胃微生物如细菌、原虫以及纤毛虫等的研究一直是反刍动物研究的重要方面。它们不仅可以对饲料纤维、淀粉进行降解,日粮蛋白质也是它们的发酵底物之一,此外,内源性的含氮物质和日粮中添加的氮源物质都可被它们代谢利用。在瘤胃微生物产生的各种降解酶的作用下,饲料养分被逐级降解进行转化,但它们的作用机理及相互作用尚不完全清楚,一直是反刍动物营养研究的重点。为此,文章对瘤胃微生物对宿主动物氮源物质的作用及其需求作一介绍,以便为深入研究作一参考。  相似文献   

10.
瘤胃微生物,如细菌、原虫以及纤毛虫等微生物的研究一直是反刍动物研究的重要方面。它们不仅可以对饲料纤维、淀粉进行降解,日粮蛋白质也是它们的发酵底物之一。此外,内源性的含氮物质和日粮添加的氮源物质都可被它们代谢利用。在瘤胃微生物各种降解酶的作用下,饲料养分被逐级降解进行转化。但是它们的作用机理及相互作用尚不完全清楚,一直成为反刍动物营养研究的主要任务之一。为此,本综述对瘤胃微生物对宿主动物氮源物质的作用及其需求作一介绍,以便为日后的深入研究作一参考。  相似文献   

11.
The objective of this study was to compare the application of different in vitro and in situ methods in empirical and mechanistic predictions of in vivo OM digestibility (OMD) and their associations to near-infrared reflectance spectroscopy spectra for a variety of forages. Apparent in vivo OMD of silages made from alfalfa (n = 2), corn (n = 9), corn stover (n = 2), grass (n = 11), whole crops of wheat and barley (n = 8) and red clover (n = 7), and fresh alfalfa (n = 1), grass hays (n = 5), and wheat straws (n = 5) had previously been determined in sheep. Concentrations of indigestible NDF (iNDF) in all forage samples were determined by a 288-h ruminal in situ incubation. Gas production of isolated forage NDF was measured by in vitro incubations for 72 h. In vitro pepsin-cellulase OM solubility (OMS) of the forages was determined by a 2-step gravimetric digestion method. Samples were also subjected to a 2-step determination of in vitro OMD based on buffered rumen fluid and pepsin. Further, rumen fluid digestible OM was determined from a single 96-h incubation at 38°C. Digestibility of OM from the in situ and the in vitro incubations was calculated according to published empirical equations, which were either forage specific or general (1 equation for all forages) within method. Indigestible NDF was also used in a mechanistic model to predict OMD. Predictions of OMD were evaluated by residual analysis using the GLM procedure in SAS. In vitro OMS in a general prediction equation of OMD did not display a significant forage-type effect on the residuals (observed - predicted OMD; P = 0.10). Predictions of OMD within forage types were consistent between iNDF and the 2-step in vitro method based on rumen fluid. Root mean square error of OMD was least (0.032) when the prediction was based on a general forage equation of OMS. However, regenerating a simple regression for iNDF by omitting alfalfa and wheat straw reduced the root mean square error of OMD to 0.025. Indigestible NDF in a general forage equation predicted OMD without any bias (P ≥ 0.16), and root mean square error of prediction was smallest among all methods when alfalfa and wheat straw samples were excluded. Our study suggests that compared with the in vitro laboratory methods, iNDF used in forage-specific equations will improve overall predictions of forage in vivo OMD. The in vitro and in situ methods performed equally well in calibrations of iNDF or OMD by near-infrared reflectance spectroscopy.  相似文献   

12.
大庆市羊东毕吸虫病流行病学调查   总被引:1,自引:0,他引:1  
对大庆市羊东毕吸虫病的流行病学进行了调查研究。结果表明,大庆有3种东毕吸虫,即程氏东毕吸虫(O.cheni)、土耳其斯坦东毕吸虫(O.turkestanica)和土耳斯坦东毕吸虫结节变种(O.turkestanican var.thuberculata);中间宿主螺类有1种,即卵萝卜螺;东毕吸虫病在大庆分布很广,所调查的4区2县均有发生,羊东毕吸虫平均感染率分别为50.33%,平均死亡率为21.12%,大庆羊急性病例发病时间为8月上旬至10月下旬,慢性病例为11月上旬至翌年2月中旬。  相似文献   

13.
中国圈养野生动物疫苗使用调查   总被引:1,自引:0,他引:1  
2005年对中国动物园协会单位中的18家动物园饲养野生动物疫苗免疫情况进行调查。受调查动物园在野生动物疫苗使用和动物种类方面具有一定的代表性。调查结果显示动物园动物现共使用18类36种疫苗,预防31种疫病。其中哺乳动物使用14类24种疫苗,预防24种疫病;禽类使用4类12种疫苗,预防7种疫病。使用范围最广的有禽流感、犬瘟热疫苗等、新城疫疫苗、猫瘟热疫苗等。共有24目58科动物接种疫苗,其中食肉动物类1目8科,食草动物类3目9科,杂食动物类2目3科,禽类18目38科。研究结果提示应加强动物园之间疫病信息交流、防疫资源的利用、疫病监测和研究,加大对动物园动物疫病的研究投入,逐步建立动物园动物统一的防疫规程。  相似文献   

14.
15.
Information gathered from cases of fowl cholera (FC) in commercial turkey flocks through case records, flock records, and telephone and mail surveys was used to estimate disease costs. The cost to the Georgia commercial turkey industry in 1986 from preventive measures, treatment of outbreaks, and production losses from the disease was estimated at $634,545. The cost of FC per kg of live production was estimated to be $0.015.  相似文献   

16.
猪伪狂犬病是由伪狂病病毒(Pseudorabies virus PRV)引起的急性传染病。其特征是成年猪常为隐性感染,可有流产、死胎、呼吸系统症状,新生仔猪除神经症状外还可侵害消化系统,并伴大批死亡。本病已经给全世界的养猪业造成严重的损失,我国许多地区已报道该病。为进一步探讨该病的控制、净化措施,我们对12个养猪场共856分血清采用美国嗍公司的ELISA试剂盒进行了抗体检测。  相似文献   

17.
In 5 cases of glaucoma (2 from trauma, 2 from narrowed drainage angles, 1 secondary to lens extraction), cyclocryotherapy was used to control intraocular pressure. In all cases the intraocular pressure decreased, with the usual result being a cosmetic and painless but blind eye.  相似文献   

18.
In 2007, 678 pigs of all age groups out of 347 different farms from Lower Saxony and Northrhine-Westphalia and 86 persons occupationally exposed to pigs were investigated for their nasal colonisation with methicillin-resistant Staphylococcus areus (MRSA) by the Field Station for Epidemiology of the University of Veterinary Medicine Hannover and the Robert Koch-Institute. At the individual animal level, a frequency of positive results of 13% (n = 85 positive animals) and at the herd level, a frequency of positive results of 18% (n = 62 positive herds) were found. All isolates were assigned to the Multilocus Sequence Typing Type ST398. Within MRSA-positive herds, there were more MRSA-negative than MRSA-positive animals. Among the occupationally exposed persons (veterinarians, laboratory personnel and meat inspection personnel), 20 persons (23%) showed a nasal colonisation with MRSA ST398. A quite strong association between the intensity of the contact to pigs with the frequency of nasal colonisation in the occupationally exposed persons was detected. None of the animals or the humans nasally colonised by MRSA ST398 showed any clinical symptoms of a staphylococcal infection. Conclusions are drawn on the herd and intra-herd prevalence of the nasal colonisation of pigs with MRSA ST398 in pigs, but especially on which questions need to be addressed by further research.  相似文献   

19.
为了解西藏拉萨市家禽禽流感抗体水平,2017年8月随机选择免疫过H5禽流感疫苗的8个规模养殖场、2个散养户、3个活禽交易市场,共13个群体,采集1 041份家禽血清样品进行H5、H7、H9亚型禽流感HI抗体检测。结果显示:H5亚型禽流感免疫抗体合格率为45.73%,H7、H9亚型抗体阳性率分别为21.13%、52.64%;养殖场、散养户和活禽交易市场的不同亚型抗体水平存在较大差异,规模化养殖场的H7亚型抗体阳性率最高(29.92%),活禽市场的H5、H9亚型阳性率最高(78.16%、79.31%),散养户的所有亚型抗体阳性率均最低。结果表明,拉萨市H5亚型禽流感疫苗免疫效果较差,特别是散养户,疫病发生风险较高,H7、H9亚型疑似自然感染率较高,应进一步查明原因,及时采取相应的措施,防止疫情发生。  相似文献   

20.
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