内蒙古地区部分奶牛场副结核病的血清学调查

采用ELISA检测方法对内蒙古地区17个奶牛场的2 391头奶牛进行牛副结核血清学检测。结果表明,大型奶牛场副结核的血清阳性率较低,在0~5%之间;小型奶牛场的副结核血清阳性率较高,平均阳性率为14.1%。调查结果提示,内蒙古地区奶牛场存在牛副结核病的流行,对该病的防控工作应给予高度重视。     

奶牛乳房炎主要病原菌基因检测技术研究进展

奶牛乳房炎是奶牛三大疾病之一,给奶牛业带来严重经济损失的同时,也间接影响人类的健康。奶牛乳房炎主要病原菌快速、准确的诊断对奶牛乳房炎的治疗与预防具有重要的意义。文章全面综述了PCR、real-time PCR、基因芯片和环介导等温扩增(LAMP)技术在奶牛乳房炎主要病原菌诊断中的应用,旨在为奶牛乳房炎的综合防制提供参考。     

荷斯坦奶牛的三阶段饲养试验

针对奶牛的生长发育特点,将围产期与产奶牛细分为3个阶段,即围产前期(产前21d到分娩)、围产后期(分娩到产后21d)、产奶期(产后21d到产奶结束),并根据3个阶段的生长发育特点和营养需求建立饲养管理程序。试验结果表明,干奶期和围产期饲养程序可以降低胎衣不下、产褥热、酮病和子宫炎的发病率(P<0.05),试验组产奶量比对照组高出6.08kg,差异显著(P<0.05),2组的乳成分没有显著变化(P>0.05)。     

Beef production from cull dairy cows: a review from culling to consumption

Although more than 3 million head of dairy cows enter the food supply chain in the U.S. every year, research on this topic remains limited and scarce. Meat production from dairy cows is a significant component of beef production, accounting for almost 10% of U.S. commercial beef production. Thus, the purpose of this review is to demonstrate the importance of dairy cows as a beef source, and to provide an overview on topics from farm to meat product—culling, marketing, transportation, welfare, body composition and its relationship with lactation particularities, carcass characteristics, meat quality, and traceability. Current scientific evidence has shown that culling a dairy cow at an appropriate time has beneficial effects on cow welfare and, consequently, cow value. During marketing the dairy cow is visually evaluated for health and factors associated with its expected carcass value; thus, marketing a well-conditioned cow will ensure that the animal is fit for transportation and provides high carcass yield. However, limitations such as low body condition score, lameness or mobility problems, and visual defects remain persistent. Even though beef harvest plants accommodate cows in all body composition states, the current carcass grade system does not reflect the mature cow industry needs. Therefore, improvement of the grading system could maximize carcass utilization and increase cow carcass value by recognizing subprimal cuts that could be merchandised as whole muscle cuts. Lastly, implementation of a traceability system would unify information from the farm to harvest assisting the industry in making further advancements.     

日粮阴阳离子平衡在奶牛生产中应用的研究进展

日粮中的阴、阳离子对奶牛的正常生产和健康有着重要的意义,它们不仅影响奶牛体液的酸碱平衡和渗透压、机体的代谢活动及多项生理指标,而且在奶牛不同的生理阶段,适宜的日粮阴阳离子平衡能提高奶牛的采食量、生产性能,还能有效预防奶牛的产后瘫痪等疾病。作者现就日粮阴阳离子平衡(dietary cation anion balance,DCAB)在奶牛上的应用进行综述,为生产实践中合理应用提供一定的理论基础。     

Relationships between urine pH and electrolyte status in cows fed forages

Data of 20 balance measurements from Holstein dairy cows and urine samples from 24 Japanese Black beef cows were collected to evaluate the relationships between urine pH and electrolyte status in cows fed forages. The ratio of forages in the diet was 70–100% in dairy cows and beef cows were fed Italian ryegrass silage and wheat bran. Mean urine pH in dairy cows was 8.10, ranging from 7.27 to 8.71, and that in beef cows was 7.73, ranging from 7.42 to 8.12. There were positive correlations between urine pH and urinary K contents (P = 0.0012) or K intake (P = 0.019) in dairy cows, although plasma Na, Cl and K had no effect on urine pH. There was a weak negative correlation (P = 0.039) between urine pH and urinary Na content in dairy cows. However, there were no significant correlations between urine pH and urinary Na, Cl and K contents in beef cows. These results indicate that the concentrated urinary K due to the increased K intake may directly enhance urine pH in dairy cows fed mainly forages.     

奶牛乳房炎研究现状

回顾了近几年来有关奶牛乳房炎的研究情况 ,综述了乳房炎对奶牛饲养业的危害和造成的损失 ,发病奶牛所表现的临床症状及乳汁性质的变化 ,以及诊断奶牛隐性乳房炎常用的方法。阐述了该病发病的原因和发病规律。该病的发生在不同年龄的奶牛差异显著 ,同一奶牛的不同乳区也有一定差异 ;该病常见病原有金黄色葡萄球菌、链球菌和大肠杆菌等 ;季节、气温等因素对该病的发生有显著的影响 ;微量元素的缺乏可以使易感奶牛发病。另外 ,乳房炎的发生还与管理因素有一定关系。文章还总结了针对该病的部分治疗措施 ,表明环丙沙星、转移因子以及中药如丹参等在对该病的治疗效果比较明显     

奶牛阴离子日粮的配制与应用

目前防治奶牛产褥热效果较好的方法是给产犊前3—5周的经产怀孕母牛饲喂阴离子日粮。但高量阴离子盐类适口性差，对采食量产生不良影响，因此想要地通过添加阴离子盐类来防止产褥热并期望得到应有的效果，有时是不可能的。针对该问题，本文介绍了阴离子日粮的配制与应用的方法。     

不同季节、生长阶段对奶牛粪便主要污染指标的影响

为了解规模化奶牛场产生的粪便对环境污染的危害程度,本文对规模化奶牛场育成牛和成乳牛粪便主要污染指标进行了特性分析。结果表明,季节因素对育成牛及成乳牛粪便特性的影响显著(P<0.05)。生长阶段对粪便含水率的影响差异显著(P<0.05),而对有机质、氮、磷、铜、锌、钾的影响差异不显著(P>0.05)。     

同一日粮下泌乳牦牛与干奶牦牛消化代谢能力的比较研究

在同一日粮条件下,对泌乳牦牛和干奶牦牛的消化代谢能力进行了比较研究。结果表明,在泌乳牦牛和干奶牦牛体内,日粮消化率间无明显差异（Ｐ＞０．０５）,能量代谢率间差异极显著（Ｐ＜０．０１）;蛋白质代谢在干奶牦牛体内为正平衡,而在泌乳牦牛体内为负平衡;在干奶牦牛体内,钙、磷代谢均为负平衡,而在泌乳牦牛体内,钙为正平衡,磷为负平衡。     

Development of enteric methane emission factors for Holstein-Friesian and Norwegian first lactation cows

Abstract

The objectives were to accurately quantify enteric methane (CH₄) emissions for first lactation dairy cows and to use these data to develop CH₄ prediction equations. Calorimeter measurements and production data were used to calculate CH₄ emissions for Holstein-Friesian (HF, n?=?32) and Norwegian (n?=?32) first lactation cows during a 305-d lactation period. Methane outputs were similar between HF and Norwegian (123 vs. 126?kg/305 d) when offered high-concentrate diets, but HF produced more CH₄ (P?<?0.05) than Norwegian (105 vs. 98?kg/305 d) when given low-concentrate diets. The HF offered high-concentrate diets had a lower (P?<?.05) CH₄ emission per energy-corrected milk yield (16.3?g/kg) than the other three treatments (19.7–20.4?g/kg). These data were then used to develop CH₄ prediction equations, which provide an alternative approach to estimate enteric CH₄ emissions for HF and Norwegian first lactation dairy cows.     

Comparison of cholesterol levels among lipoprotein fractions separated by anion-exchange high-performance liquid chromatography in periparturient Holstein–Friesian dairy cows

Changes in lipoprotein profiles occur in dairy cows during the periparturient period and in cows with transition cow disease. Here, the lipoprotein profiles of Holstein–Friesian dairy cows during the periparturient period were obtained by anion-exchange, high-performance liquid chromatography to evaluate the usefulness of lipoprotein profile evaluation during the periparturient period and in cows with fatty liver and milk fever. Lipoprotein levels (including total and high- (HDL-C) and low-density lipoprotein (LDL-C) cholesterol) in 10 healthy cows were low 4 weeks prepartum, with the lowest values at calving or within 1 week of calving; the values increased at 8 weeks postpartum. The lipoprotein levels were measured in 16 cows diagnosed with fatty liver (n=10) or milk fever (n=6) and compared to 10 healthy dairy cows. A significant difference was observed in HDL-C between healthy cows (at calving and 1 week postpartum), and the fatty liver and milk fever cows. Cows with fatty liver and milk fever had a lower mean HDL-C than the 10 healthy dairy cows at calving and 1 week postpartum. HDL-C might be a good indicator of energy balance for differentiating healthy cows from those with transition cow disease.     

"乳康2号"对奶牛细菌性乳房炎的疗效研究

用＂乳康2号＂治疗临床型乳房炎奶牛37头。结果表明,治愈28头,有效6头,无效3头,总有效率为91.89%,平均治疗时间4.7d。对采集的37头奶牛治疗前的42个乳区奶样,进行细菌学检查,有33个乳区检出与乳房炎有关的病原菌,占78.57%。检出病原菌5种,主要为无乳链球菌、停乳链球菌、金黄色葡萄球菌、乳房链球菌和大肠埃希菌。停药后采集33个乳区奶样,结果有14个乳区细菌转阴,细菌转阴率为42.42%。在转阴的病原菌中,大肠埃希菌转阴率最高（100%）,其次是混合感染（60.00%）和乳房链球菌（50.00%）。     

我国奶牛乳房炎无乳链球菌抗生素耐药性研究

为了查明我国奶牛乳房炎无乳链球菌对抗生素耐药情况,指导临床合理用药,从我国部分地区奶牛场采集的临床型奶牛乳房炎病乳中分离鉴定出无乳链球菌115株,采用K-B纸片法测定了这些菌株对抗生素的耐药情况。结果表明,无乳链球菌对目前临床上使用的大部分抗生素,如头孢唑啉、头孢噻肟、丁胺卡那霉素、卡那霉素、庆大霉素、四环素、强力霉素、麦迪霉素、林可霉素、氟苯尼考、多黏菌素B、环丙沙星、氟哌酸、氨苄青霉素/舒巴坦、头孢噻肟/棒酸和头孢他啶/棒酸均比较敏感;但对青霉素G、氨苄青霉素、链霉素、恩诺沙星、阿莫西林/棒酸和复方新诺明等有一定耐药性,其耐药率达50%～100%。     

奶牛热应激研究进展

当前以源自北欧的不耐热品种荷斯坦牛作为我国主要的奶用品种遍布全国各地,随着其生产性能的不断提高其热应激的表现也越来越严重。特别是在南方农区热应激造成的经济损失十分明显。因此,研究采取有效的预防措施,消除热应激对奶牛的影响,对保证奶牛高产稳产具有重要的经济意义。     

猪卵母细胞体外成熟和孤雌培养体系的建立和优化

试验系统探讨了猪卵母细胞的体外成熟和孤雌激活方法。结果表明:在成熟液中分别添加FSH(促卵泡素:0.1ng/mL)和hMG(人绝经期促性腺激素:0.01IU/mL)的卵母细胞成熟率差异显著,但2组间的分裂率和囊胚率差异不显著。在成熟液中添加0、10、30、50、70ng/mL或90ng/mL的EGF(表皮生长因子),50ng/mLEGF组的分裂率达到84.90%,囊胚率达到30.20%,显著高于其余各组。分别使用以TCM-199和NCSU-23为基础液的成熟液来成熟培养猪卵母细胞,NCSU-23组的分裂率,成熟率和囊胚率均高于TCM-199组。使用离子酶素激活方法和电激活方法进行对比,离子酶素激活后孤雌胚胎发育效果好,差异极显著(P<0.01)。     

多种因素对奶牛超数排卵效果影响的研究

试验探讨了激素处理、季节、供体母牛体况、胎次等因素对奶牛超数排卵效果的影响,为连续超排研究奠定了基础。结果表明:CUE-MATE法和自然发情法超数排卵效果没有显著差异(P>0.05),但CUE-MATE法处理周期短;中等、上等体况的供体母牛超数排卵效果显著好于体况较差的牛(P<0.05);冬、秋季节超数排卵效果显著高于春季(P<0.05);经产母牛和青年牛超数排卵效果没有显著差异(P>0.05)。由此可见,奶牛规模化胚胎生产可采用CUE-MATE法,选取中等以上体况在秋、冬季节进行。     

奶牛乳房炎治疗药剂——乳疾宁的研究

我所研制的乳疾宁由一液和二液组成，一液具有广谱抗菌作用，二液有促进乳房内坏死，凝固物溶解，排除的功能。该药剂为乳房局部用药，每日挤奶后将一液和二液按１：１的比例混合后注入乳房乳池５０～１００ｍｌ（１日２～３次）对机体无不良影响，不被机体吸收，试验治疗乳房炎患牛２８４例，总有效率为９７．５％，治愈率８６．６％，区域试验治疗４７９０例，治愈率为８７．５％，该药液保质期至少２年。     

新疆郊区奶牛健康养殖状况调查

[目的]以新疆天山北坡昌吉市郊区散养和规模化奶牛养殖场为对象,对奶牛体况、环境压力、牛体污染、乳房炎、血液性状等健康指标进行了调查分析。[方法]选择奶牛散养户5户和规模化奶牛养殖场的干奶期、泌乳初期和泌乳中期奶牛,分别于冬季和夏季进行体况、环境压力、乳房炎、血液性状等健康指标的测定与分析。[结果]干奶牛体况值略低于奶牛体况评分的理想值（3．5）;奶牛呼吸数夏季增加,超过50次／min;规模化奶牛养殖场的污染程度比散养户要高,尤其是冬季50％以上奶牛的牛体污染评价值高于3。规模化奶牛养殖场的奶牛乳房炎发病率达40％,并发现了感染金黄色葡萄球菌的病例。低血糖奶牛占一半以上．特别是干奶期比较突出。血液Alb和BUN偏低,干奶期牛群的BUN大多低于7mg／dL。血液中谷草转氨酶（AST）偏高,谷氨酰转肽酶（GGT）偏低,Ca含量正常,Mg含量较低。[结论]规模化奶牛养殖场存在干奶期奶牛能量及蛋白质不足;冬季环境恶劣并且污染程度较重,牛体污染及乳房炎发病率高;飞节损伤引起的肝功能衰退等现象,需要改进。     

Effects of chelated Zn/Cu/Mn on redox status,immune responses and hoof health in lactating Holstein cows

To evaluate the effects of chelated Zn/Cu/Mn on redox status, immune responses and hoof health in lactating Holstein cows, 48 head in early lactation were divided into healthy or lame groups according to their gait score. Cows were fed the same amount of Zn/Cu/Mn as sulfate salts or in chelated forms for 180 days, and foot-and-mouth disease (FMD) vaccine was injected at day 90. The results showed that lame cows had lower antioxidant function, serum Zn/Mn levels, hair Cu levels, and hoof hardness. Moreover, increased antioxidant status, FMD antibody titers, serum and hair levels of Zn/Cu/Mn, and hoof hardness and decreased milk fat percent and arthritis biomarkers were observed in cows fed chelated Zn/Cu/Mn. In summary, supplementation with chelated Zn/Cu/Mn improved antioxidant status and immune responses, reduced arthritis biomarkers, and increased accumulation of Zn/Cu/Mn in the body and hoof hardness in dairy cows.