奶牛隐性乳房炎发生规律的研究

对433头泌乳奶牛隐性乳房炎发病规律进行了调查研究。发现该牧场奶牛隐性乳房炎发病率为29.33%,乳区阳性率为33.60%。病原菌的总检出率为91.67%,引起隐性乳房炎发生的致病菌主要为金黄色葡萄球菌和大肠杆菌,分别占总检出率的37.88%和16.67%。同时对发病率与乳区、年龄、胎次及日均产奶量等的关系进行了相关分析。结果表明,各乳区间发病率差异不显著;隐性乳房炎的发病率随着奶牛年龄的增加而有所上升(P<0.01);不同胎次组间发病率差异显著(P<0.05);日均产奶量20 kg以下的牛群发病率极显著高于日均产奶量20 kg以上的牛群(P<0.01)。     

奶牛隐性乳房炎的流行病学调查

为了解开封市奶牛隐性乳房炎的发病情况,选择年龄2.5～10岁,胎次为1～8次的250头健康荷斯坦牛970个乳区进行连续检测,结果表明:隐性乳房炎的发病率在不同牛舍间差异不显著;在2-4月份隐性乳房炎的头阳性率和乳区阳性率均随着月份的增加而不断下降;在各胎次均有发生,且随胎次的增加头阳性率增加;随着泌乳期的延长乳区阳性率增加;日产奶量≤20 kg的奶牛的隐性乳房炎感染率高于日产奶量≥20 kg的奶牛.     

石河子某奶牛场隐性乳房炎的普查与分析

采用BMT法对石河子某奶牛场416头泌乳荷斯坦奶牛进行隐性乳房炎检测,测得该牛场隐性乳房炎的头阳性率和乳区阳性率分别为62.02%和37.58%。同时,分析了该牛场隐性乳房炎的发病率与胎次、乳区、牛舍、泌乳时间等因素的关系。     

石河子某奶牛场隐性乳房炎的普查与分析

采用BMT法对石河子某奶牛场416头泌乳荷斯坦奶牛进行隐性乳房炎检测,测得该牛场隐性乳房炎的头阳性率和乳区阳性率分别为62.02%和37.58%。同时,分析了该牛场隐性乳房炎的发病率与胎次、乳区、牛舍、泌乳时间等因素的关系。     

体细胞数与奶牛乳房炎的相关性分析

奶牛乳房炎是奶牛场的常发病之一,我国发病率大约为73.19%,此病对奶牛产奶量和乳质量都会产生明显影响,可使产奶量下降10%~15%,并且会造成乳质量下降。有学者提出生鲜牛乳中体细胞与奶牛乳房炎存在着内在的必然联系。本文主要分析DHI(奶牛群体改良)技术中体细胞数与奶牛乳房炎的相关性,希望对奶牛养殖场(户)提供一定的帮助。     

南京地区奶牛乳房炎的现状、成因与防制

通过对南京市不同类型奶牛场奶牛临床型乳房炎、隐性乳房炎的发病率、发病规律、发病因素及发生危害进行调查与分析 ,并提出防制奶牛乳房炎的配套措施。     

隐性乳房炎病因调查

本文对太原市小店区某镇的奶牛乳房炎发病情况进行了调查。通过用LMT法和乳汁pH值检验法相结合诊断隐性型乳房炎,对发病情况及被检牛的挤奶方式、年龄、胎次、饲养管理、卫生及泌乳阶段等情况调查,表明随着年龄的增加,乳房炎的发病率有明显的上升;随着胎次的增加。发病率也有所上升,而以初产牛发病率最低,以7胎以上的病例所占的比例最高：泌乳阶段与乳房炎发病率有密切的关系;各乳区均可发生乳房炎：通过统计得出小店区隐性型乳房炎的发病率为47.3％。     

奶牛隐性乳房炎的诊断和防治

奶牛乳房炎是奶牛的常见病,发病后严重影响牛奶的品质,可以导致奶牛产奶量下降、增加药物费用,造成奶农的经济损失。奶牛乳房炎主要表现为临床型和隐性型．其中隐性型乳房炎的发病率明显较临床型乳房炎高。由于奶牛隐性乳房炎无临床症状,乳房和乳汁通常肉眼无可见变化,所以通过实验室群体检测．2008年3月,阿克苏市动物防疫监督站对依杆其乡某奶牛场临床健康奶牛进行乳房炎检测,隐性型乳房炎的发病率为57．3％。而对病牛进行治疗和淘汰,是防治的关键。     

广西某奶牛场乳房炎病原菌的流行调查

【目的】探索奶牛乳房炎的流行情况,分析病原菌的分布、变化及其规律,进一步阐明其引发病因,为本病的防治提供参考。【方法】通过临床诊断、加州乳房炎测试法(CMT)、革兰氏染色、菌液PCR、基因测序等方法,对某奶牛场奶牛乳房炎的发病率、及病原菌种类况以药物治疗情进行分析。【结果】临床型奶牛乳房炎的年平均发病率为8.3%,其隐性乳房炎乳占总乳区的40%。奶牛场长期使用头孢噻呋钠,林可霉素,庆大霉素,青霉素,链霉素等抗生素进行治疗,治疗效果不明显。乳房炎中分离得到的假丝酵母菌和毕赤酵母菌分别占真菌中的73.1%和25%,其中热带念珠菌占38.5%;大肠杆菌和链球菌分别占细菌中的22.7%和9.1%。【结论】该奶牛场的奶牛乳房炎的年发病率及隐性乳房炎乳较高,真菌比细菌感染率要显著,这可能与长期使用抗生素治疗、气候和牛场环境等因素密切有关。     

奶牛乳房炎对其产奶性能的影响

为了研究乳房炎对奶牛产奶性能的影响,采集西安市某奶牛场618头荷斯坦奶牛完整记录的各月DHI报告中体细胞数据和兽医记录,统计分析乳房炎发病率、临床乳房炎及其患病时期对奶牛305d奶量的影响。同时另采集108头奶牛有完整记录的150个泌乳期的1 368条DHI记录,对比分析不同体细胞水平对奶牛胎次奶量、日产奶量和乳成分含量的影响。结果表明,隐性乳房炎年发病率为50.5%,临床乳房炎头阳性率为4.37%,头次阳性率为8.25%。临床乳房炎极显著降低奶牛305d奶量(P0.01),而在泌乳盛期患病的牛305d奶量降低可达32.5%。隐性乳房炎对奶牛生产性能的影响随患病程度加重而加重,平均体细胞数20万/mL胎次奶量就会显著减少(P0.05),而体细胞数50万/mL,胎次奶量极显著降低(P0.01)。奶牛泌乳盛期患隐性乳房炎比泌乳中后期患隐性乳房炎对产奶量和乳蛋白率的影响更大,患病程度重的奶牛相对于健康牛日平均奶量显著降低(P0.05),乳蛋白率显著增高(P0.05),乳脂率显著降低(P0.05)。     

我国奶业的现状和洛阳奶业的发展

目前我国奶业的现状是消费量低 ,产业化程度和科技含量低 ,奶品质量差。在分析我国奶业现状的基础上 ,就洛阳奶业的发展提出了一些建议。     

Evaluation of automated in-line precision dairy farming technology implementation in three dairy farms in Italy

In recent decades, dairy farms have been exposed to wide variation in profit levels due to a considerable variability of milk price, and energy and feed costs. Consequently, it is necessary for the dairy industry to improve efficiency and productivity by adopting innovative technologies. The automated in-parlour milk analysis and separation is mainly useful to produce low or high quality milk and to monitor the animal health status. Milk with high levels of protein and fat contents may reduce the intensity of standardization during cheesemaking process, reducing production costs. The study aimed to evaluate the efficiency of real-time milk separation during milking and the performance of the milking machine after implementation of AfiMilk MCS. In addition, the economic aspects were assessed. The separation of milk required the existing milking parlors to be equipped with an additional milkline to allow channeling milk with low and high coagulation properties into two different cooling tanks. The results showed that the high coagulation milk fraction, compared to the bulk milk, increased in fat (from 18% to 43%) and protein (from 3% to 7%) concentration. The technology tested has given promising results showing reliability and efficiency in milk separation in real time with affordable implementation costs.     

Automatic blood sampling in dairy cows

Loose housing systems for dairy cows are becoming increasingly common, raising new questions in the area of animal health and welfare. Some of these questions can be addressed by studying the variation in blood parameters, such as glucocortistioids. However, the traditional manual blood sampling procedure can in itself affect the responses of the animal. To address this issue we have developed a device for automated collection of multiple blood samples. The device is placed on the back of the animal and allows the animal to be kept in all types of environments, either alone or in social groups. The animal can move freely: no restraints and no handling of the animal are necessary during blood sampling.Three experiments were conducted to study the performance of the system and how the blood sampling procedure affected the cortisol responses in dairy cows. In the first experiment the accuracy of sample size and timing were investigated.In the second experiment, automatic samples were collected from six cows kept in tie-stalls, with samples taken at 3-min intervals for 38 min. At 12, 24, 36 and 38 min, a manual sample was taken by vein puncture. None of the cows showed a consistently increased cortisol response to automatic sampling, while two cows showed increased cortisol concentration after vein puncture.In the third experiment automatic blood sampling was conducted with 12 cows kept in a loose housing system. In the morning, over a period of 1.5 h, 14 blood samples were taken at varying time intervals from each cow. In the afternoon, over a period of 2.5 h, a further 14 samples were taken. Cortisol concentrations in the blood samples suggest that the cows were not affected by the blood sampling procedure.On some occasions during these experiments, it was not possible to get a sample. For the manual vein puncture 3 out of 24 samples (12.5%) were not successfully taken within a time limit of 2 min. During the automatic blood sampling process, the catheter occasionally became twisted and blocked by the movement of the cow's head. This occurred in 8 out of 84 samples (9.5%). In four of the manual samples, considerable hemolysis had occurred during the sampling procedure. No hemolysis was observed in the automatic blood samples.Automated blood sampling offers the opportunity to collect a series of samples without disturbing the animal. Data suggest that automatic blood sampling is a superior alternative to manual blood sampling, even in a tie barn.     

奶牛场粪污制备卧床垫料过程中物料性质及污染物含量的周年变化规律

为了考察奶牛场粪污制备卧床垫料过程中的牛粪性质及相关污染物含量的周年变化规律,选择天津市一家规模化奶牛养殖场作为研究对象,进行不同阶段、不同季节的连续采样,并对样品中的TN、TP、pH、含水率、有机质、粪大肠菌群和Cu、Zn等重金属进行了系统检测分析。检测数据分析显示:泌乳牛牛粪中的TN、TP、VS、Cu、Zn的排放量存在显著性季节差异(P0.05),且TN、TP、Cu、Zn、Cd的排放量均以冬季最高;经过BRU(Bedding Recovery Unit)好氧发酵处理后,再生牛粪固体中的含水率、重金属Zn和粪大肠菌群的含量出现不同程度的降低,而TN、TP和重金属Cu的含量则基本呈现升高趋势。     

奶山羊乳房炎的淋巴细胞凋亡变化

通过AnnexinⅤ-FITC/PI双染流式细胞术测定泌乳1、6、14、21、28、35、45 d(强制退化10 d)健康及乳房炎奶山羊血液、脾、乳上淋巴结及肠系膜淋巴结淋巴细胞凋亡率的变化。结果表明,乳房炎组(M)奶山羊血液、脾、乳上淋巴结及肠系膜淋巴结淋巴细胞凋亡率(%)显著或极显著高于对照组(C)奶山羊(P<0.05,P<0.01),表明乳房炎奶山羊通过增加淋巴细胞凋亡下调炎症反应以维护自身健康。     

杭州市奶牛结核病流行情况调查

结核病是由结核杆菌引起的人畜共患慢性传染病。采用牛型结核分枝杆菌PPD皮内变态反应试验,2003—2006年对杭州市奶牛结核病感染情况进行调查,4年间共检牛52 160头,检出阳性牛590头,平均阳性率为1.13%。2004—2005年杭州市奶牛结核病发生主要集中在临安市和建德市。从奶牛结核病流行趋势分析,2004—2006年奶牛结核病平均阳性率(1.42%),高于2000—2003年的水平(0.28%)。存栏20头奶牛以下的养殖户结核病发生率(33.33%),明显高于养殖规模场(22.41%)。     

奶牛育种中的遗传进展

分别采用直接回归法、公牛加权均值回归法、最小二乘回归法和BLUP回归法,对福建省南平市2个奶牛场的305d 胎产奶量遗传进展进行了评估.结果表明:整个16a期间平均遗传进展为60kg左右,约为均值的1.34%(前8a为26-35kg,约为均值的0.68%-0.89%;后8a为96-131kg左右,约为均值的1.97%-2.73%).16a间的平均世代间隔是:父-女6.59a,母-女5.94a,平均6.26a.由于评估遗传进展的需要,同时采用父系半同胞相关法对奶牛305d 胎产奶量遗传力进行了估计,其遗传力为0.29.     

奶牛真胃变位的手术治疗

真胃变位是奶牛的常见真胃疾病,近年来该病的发生呈上升趋势,其发病原因多而复杂,日粮酸度过高或饲喂易发酵饲料导致产酸过多常能引起真胃变位;一些代谢性疾病如低血钙、酮病或胎衣滞留、子宫炎以及前胃和肠发生疾病时,由于胃肠蠕动弛缓或停滞,病牛食欲下降,瘤胃体积变小,腹腔空间变大,真胃由弛缓而产气扩张,亦能引起变位的发生;怀孕后期随着胎儿的逐渐增大造成对瘤胃向左侧的推挤,使右侧腹底真胃区相对空虚,真胃左移,分娩后腹压降低,瘤胃下降,常造成真胃左方变位;高产奶牛由于后躯硕大,腹腔空间大,增加了真胃的活动性,从而导致真胃变位发生率的增高.另外应激对真胃变位的发生也有一定的促进作用.     

奶牛梨形虫病的调查及防治研究

奶牛梨形虫病是由蜱吸血传播的一种血液原虫病,过去称为焦虫病.其临床特征为发热、贫血、黄疸、淋巴结肿大等.近几年由于奶牛饲养量的增加和运输交易的频繁,该病的发病率逐年上升,严重影响奶牛业的发展,现已成为危害奶牛健康最严重的疾病之一.我们从2001年至2003年对该病进行了流行病学调查、诊断和防治研究,现将情况报告如下.     

放射免疫通信诊断奶牛子宫内膜炎的研究

应用放射免疫分析法对３０头正常奶牛和临床确诊有子宫内膜炎的５４头奶牛奶中孕酮含量变化的周期模式进行对比测定，发现正常奶牛奶中孕酮含量变化周期有规律，而患子宫内膜炎的奶牛奶中孕酮含量变化无规律，波动大，脉冲式或发情后孕酮跳跃式上升到最大值。根据这一特点，对５９７头奶牛测定奶中孕酮含量变化的周期模式，诊断出１４２头奶牛有子宫内膜炎。经临床复核，准确率达９８．６％。