A herd level analysis of a Corynebacterium pseudotuberculosis outbreak in a dairy cattle herd

Corynebacterium pseudotuberculosis infection in an Israeli dairy cattle herd is described. The disease was characterized by ulcerative granulomatous lesions, which occurred in an epidemic form. Thirty-two cows and two heifers were affected, the ratio of the number affected to number at risk being 17.5 : 1 and 9.5 : 1, respectively. The culling rate was 50% of the affected animals. Most of the affected animals were cows (91.2%), with one first-calving cow (2.9%) and two heifers (5.9%) also affected. The infection occurred during the summer to autumn months (August-December), and lasted 118 days. The incubation period is about 2 months. The disease appeared in two clinical forms - cutaneous and mastitic - or as a mixed form. C. pseudotuberculosis organisms that were isolated from the ulcerative granulomatous lesions and from milk samples failed to reduce nitrate. A decrease in milk production (4%) and an increase in the bulk-milk somatic cell count from a herd mean of 240 x 10(3) mL(-1) to 460 x 10(3) mL(-1) were noted during the morbidity period. The organism was isolated from milk samples of eight animals (25%). Clinical, epizootiological and microbiological aspects of the infection are described.     

奶牛新陈代谢模型研究进展

本文对奶牛新陈代谢模型研究进展进行了综述。     

奶牛重要营养素--水

本文主要介绍了水在奶牛营养中的重要作用、奶牛饮水量的计算以及影响奶牛饮水量的因素。     

黑龙江省主要栽培的禾本科牧草对奶牛的营养价值评价

通过对常见的13种栽培禾本科牧草的常规营养成分测定及用尼龙袋法测定的干物质在瘤胃72 h降解率(RDMD)的测定,结果表明:l)用营养成分和RDMD等指标进行评定,2个冰草Agropyron cristatum品种营养价值最高,猫尾草Phleum pratense次之,3个披碱草Puccinellia tenuiflora品种居中,羊草Leymuschinensis和墨西哥玉米Zea mays较差,谷莠子Setaria anceps和稗草Echinochloa crusgalli最差。2)禾本科牧草RDMD与ADF、ADL含量呈极显著负相关(P<0.05)。利用回归方程可以用ADF、ADL含量来预测禾本科牧草的RDMD。3)应用干物质采食量(DMI)、产奶净能(NEL)估测模型计算了各种禾本科牧草的分级指数(GI)值,并参照豆科和禾本科牧草质量分级标准对研究测定的禾本科牧草等级进行划分,其结果是:符合优质牧草等级的有高冰草、中间冰草,符合中等牧草等级标准的有无芒雀麦Bromus inermis、垂穗披碱草、东北羊草、吉生羊草、百特猫尾草、猎犬披碱草、润宝高丹草Sorghum×Sudan。属于劣质牧草的有粗穗披碱草Elymus dahuricus、墨西哥玉米、稗草、谷莠子。4)用单一的营养指标如化学成分、干物质降解率不能准确地评价牧草的营养价值。只有综合考虑DMI、养分含量、消化率和有效能才能对牧草的营养价值做出正确的评价。使用GI值能明显区分养分含量差异很小的不同种类牧草,这说明分级指数是评价牧草营养价值的最权威指标。     

牛源环孢子虫的形态学特征观察

对首次在乳牛粪便中发现的疑似环孢子虫卵囊的形状、大小、抗酸染色和孢子化等形态学特征进行了观察，探讨了该原虫的纯化方法。结果显示，牛源环孢子虫卵囊呈球形，直径6～10μm。直接涂片时可见卵囊内含折光性较强的成团小球体，呈桑椹胚状，淡绿色。碘液染色不着色。经改良抗酸染色后，卵囊着色变化较大，呈淡红色、深红色或不着色。新排出的未孢子化卵囊培养后可观察到孢子化的卵囊，内含2个孢子囊，每个孢子囊内含有2个折光性较强的子孢子。这些特征与人或其他动物的环孢子虫一致。环孢子虫感染阳性的粪便经Sheather＇s蔗糖漂浮法浓集后，再经蔗糖密度梯度离心，可以得到较为纯净的卵囊。     

Salmonella Dublin infection in Queensland dairy cattle

Objective: To investigate the presence of Salmonella Dublin in Queensland cattle.
Design: An epidemiological study using diagnostic laboratory information and farm records.
Procedure: Outbreaks of gastroenteritis or pneumonia in calves, and abortions and enteritis in cows were routinely investigated for the presence of salmonellae. Where S Dublin was isolated, attempts were made to gather further epidemiological information.
Results: Prior to 1983 only two outbreaks of S Dublin have been recorded in Queensland dairy cattle. In 1983 S Dublin abortions were diagnosed in dairy heifers introduced from southern Australia to south-east Queensland. Sampling indicated that at least 10% of the 500 introduced heifers were faecal excretors of S Dublin. On 3 of the 7 farms from which S Dublin was recorded, infection spread to other cattle that were in contact. From February 1985 to February 1996, 29 outbreaks of S Dublin in cattle occurred on 29 farms (28 in south east Queensland and 1 in north Queensland). Calves were primarily affected. Continuing outbreaks were confirmed on only 4 of these 29 farms. On 15 farms S Dublin infections were associated with the purchase of infected calves or cows, while another farm adjoined 2 previously infected farms. No source of S Dublin was evident for the other 13 farms, where histories were often inadequate.
Conclusion: There has been a marked increase in S Dublin outbreaks in Queensland dairy cattle since 1983. Introduction of S Dublin carrier and aborting dairy heifers from southern Australia, where S Dublin is not uncommon, was associated with the initial outbreaks.     

不同牧草在奶牛瘤胃内的降解规律

试验用尼龙袋法研究了不同种类牧草(黑麦草Lolium multiflorum、羊草Leymus chinese、返青期和盛花期紫花苜蓿Medicago sativa)的干物质(DM)、粗蛋白(CP)和粗纤维(CF)的在奶牛瘤胃内动态降解率变化规律.结果表明:在相同培养时间段内,返青期的紫花苜蓿DM的降解率显著高于黑麦草、羊草和盛花期的紫花苜蓿;不同生长期的紫花苜蓿其DM、CP的降解率差异显著(P<0.05),且返青期高于盛花期;各种牧草在48 h 的 CP 降解率都趋于平稳;经相关分析,各种牧草的DM、CP表现为强正相关关系.     

Foot lesions in lame cows on 10 dairy farms in Ireland

Background

Little is known about foot lesions in dairy cattle in Ireland, managed under a pasture based system with housing during the winter and grazing for the rest of the year. Ten Irish dairy herds, with a lameness prevalence ranging from 9 to 17 % were locomotion scored routinely during the 2013 grazing season. Lame cows were foot trimmed and foot lesions recorded.

Findings

11.8 % and 89.6 % of cows had lesions recorded on front and hind feet respectively. No lesions were found in 6.9 % of cows. Sole haemorrhage and white line disease were the most prevalent lesions, and overall 76.8 % of lesions affecting the claw horn were diagnosed on the lateral hind claw.

Conclusions

Treatment success, as measured by improved LS post treatment, was not significantly affected by the LS prior to foot trimming, the presence of lesions or the type of lesion identified. Exposure to both risk factors for lameness at housing and pasture may have resulted in the development of a combination of foot lesions typically associated with zero-grazing or all-year-round grazing management systems.     

Single step genomic evaluation for female fertility in Nordic Red dairy cattle

Joint Nordic (Denmark, Finland, Sweden) genetic evaluation of female fertility is currently based on the multiple trait multilactation animal model (BLUP). Here, single step genomic model (ssGBLUP) was applied for the Nordic Red dairy cattle fertility evaluation. The 11 traits comprised of nonreturn rate and days from first to last insemination in heifers and first three parities, and days from calving to first insemination in the first three parities. Traits had low heritabilities (0.015–0.04), but moderately high genetic correlations between the parities (0.60–0.88). Phenotypic data included 4,226,715 animals with records and pedigree 5,445,392 animals. Unknown parents were assigned into 332 phantom parent groups (PPG). In mixed model equations animals were associated with PPG effects through the pedigree or both the pedigree and genomic information. Genotype information of 46,914 SNPs was available for 33,969 animals in the pedigree. When PPG used pedigree information only, BLUP converged after 2,420 iterations whereas the ssGBLUP evaluation needed over ten thousand iterations. When the PPG effects were solved accounting both the pedigree and the genomic information, the ssGBLUP model converged after 2,406 iterations. Also, with the latter model breeding values by ssGBLUP and BLUP became more consistent and genetic trends followed each other well. Models were validated using forward prediction of the young bulls. Reliabilities and variance inflation of predicted genomic breeding values (values for parent averages in brackets) for the 11 traits ranged 0.22–0.31 (0.10–0.27) and 0.81–0.95 (0.83–1.06), respectively. The ssGBLUP model gave always higher validation reliabilities than BLUP, but largest increases were for the cow fertility traits.     

铜缺乏对奶牛肝脏金属硫蛋白代谢的影响

为阐明金属硫蛋白在铜缺乏奶牛肝脏中的代谢特征 ,选择铜缺乏区有明显临床症状的奶牛 6头 ,采集肝脏样品后用差速离心法分离肝脏金属硫蛋白 ,以Sephadex G75进行层析纯化 ,测定各部分洗脱液中金属元素铜、锌、铁、镁的含量。将 6头健康奶牛的肝脏样品作为对照。试验结果表明 ,发病奶牛肝细胞浆Sephadex G75柱层析洗脱液中铜、铁含量峰值显著高于健康奶牛 ,且在后面部分层析液中出现小峰 ;发病奶牛肝细胞浆金属硫蛋白 (MT)层析液锌、镁含量曲线峰值宽阔且高于对照组 ,第 2峰形宽大且有前移现象。结论 :铜缺乏能够改变奶牛肝脏中金属硫蛋白的代谢     

Depressed DHEA and increased sickness response behaviors in lame dairy cows with inflammatory foot lesions

Lameness is a multifactorial condition influenced by the environment, genetics, management and nutrition. Detection of lameness is subjective and currently limited to visual locomotion observations which lack reliability and sensitivity. The objective of this study was to search for potential biomarkers of inflammatory foot lesions that underlie most cases of lameness in dairy cows, with a focus on the sickness response and relevant endocrine, immune and behavioral changes. Serum and peripheral blood mononuclear cells (PBMC) were collected from eight sound and eight lame high-producing Holstein cows. Immune cell activation was investigated in PBMCs using a candidate gene approach in which the expression of pro-opiomelanocortin, interleukin-1beta, l-selectin, matrix metalloproteinase-9 and glucocorticoid receptor-alpha was measured via quantitative real time-RT-PCR. Endocrine changes were investigated by monitoring serum concentrations of cortisol and dehydroepiandrosterone (DHEA). Additionally, systematic behavioral observations were carried out to characterize a behavioral profile associated with a sickness response typical of this condition. Lame cows showed significantly lower eating (P=0.01) and ruminating (P=0.01) behaviors and higher incidence of self-grooming (P=0.04) compared to sound cows. Lame cows also showed a 23% decrease in serum DHEA (P=0.01) and 65% higher cortisol:DHEA ratio (P=0.06) compared to sound cows. However, no significant differences were found in candidate gene expression between lame and sound cows. In association with sickness behaviors, serum DHEA concentration and cortisol:DHEA ratio are promising objective indicators of inflammatory foot lesions in dairy cattle and may be useful as diagnostic targets for animals in need of treatment.     

奶牛新孢子虫病血清流行病学调查

本研究用酶联免疫吸附试验（ELISA）对采集自北京地区的94份奶牛血清（随机采集）和河北地区的55份奶牛血清（有流产史奶牛），进行Neospora caninum血清抗体检测。结果发现，北京地区随机采集的奶牛血清N．caninum抗体阳性率为18．1％（17／94），河北地区有流产史的奶牛N．caninum血清抗体阳性率为23．6％（13／55）。采用牛奶记录体系（DHI）对北京地区17头N．caninum血清抗体阳性牛进行了日产奶量、乳中蛋白率和乳脂率的测定，并与同群牛中134头阴性牛比较。结果表明，N．caninum血清抗体阳性牛日产奶量比阴性牛降低9．7％，乳中蛋白率和乳脂率分别降低20％和15．4％。初步证明N．caninum血清抗体阳性奶牛产奶量降低及奶品质的下降。对不同N．caninum抗体滴度阳性牛的泌乳期主要生产性能比较发现，其生产性能的变化与抗体滴度无明显相关性。     

肉牛和奶牛家庭牧场发展现状与对策

为保证我国肉牛养殖业和奶牛养殖业的高速发展,经过多种养殖模式的对比,发现以家庭为主体集约化生产、商品化经营的家庭牧场更加适合未来畜牧业的发展趋势,我们认为肉牛和奶牛的家庭牧场式养殖已经成为我国畜牧业未来的发展方向之一。本文对我国肉牛和奶业发达国家的奶牛的家庭牧场发展现状进行了分析,并与畜牧业发达国家的家庭牧场进行对比,总结了我国家庭牧场在发展中存在的问题,并针对这些问题提出了未来我国家庭牧场的发展对策,以期促进我国肉牛和奶牛的家庭牧场持续健康发展。     

Contagious impetigo in a dairy cattle herd

Abstract Impetigo and fürunculosis appeared in a dairy cattle herd in association with intensive showering of the lactating cows during the summer months. Heifers and dry cows in the same herd, as well as those in a neighbouring herd in the same village, which was not showered and served as a comparison herd, remained unaffected. Skin lésions declined with the termination of showering. Only six animals [three cows (7.3%) and three first-calving cows (20%)] had to be treated parenterally with antibiotics. Resumen En un rebafio de vacas de leche aparecieron cuadros de impetigo y fürunculosis asociados a las duchas frecuentes aplicadas durante los meses de verano a las vacas lactantes. Las novillas y vacas secas en el mismo rebaño, asi como las de un rebaño vecino de la misma localidad y que no recibian duchas fueron usadas como rebaño de comparación, no se vieron afectadas. Las lesiones cutáneas remitieron al dejar de aplicar las duchas. Tan solo en seis animales [tres vacas (7, 3%) y tres vacas en primer parto (20%)] fue necesario aplicar una terapia parenteral con antibióticos. [Yeruham, I., Elad, D., Perl, S., Nyska, A., Vishinsky, Y. Contagious impetigo in a dairy cattle herd (Impetigo contagioso en un rebaño de vacas de leche). Veterinary Dermatology 1996; 7 : 239–242.] Résumé Impétigo et füronculose se sont manifestés dans un troupeau laitier, en relation avec un douchage intensif des vaches allaitantes pendant les mois d'été. Les jeunes et les vaches taries du même troupeau, ainsi que celles d'un troupeau voisin du même village, non douchées et servant d'élément de comparaison, restèrent inaffectés. Les lésions cutanées ont régressé dês la cessation des douchages. Seuls six animaux (trois vaches-7, 3%-et trois vaches primipares-20%-) durent etre traités par antibiothérapie parentérale. [Yeruham, I., Elad, D., Perl, S., Nyska, A., Vishinsky, Y. Contagious impetigo in a dairy cattle herd (Impétigo contagieux dans un troupeau de vaches laitières). Veterinary Dermatology 1996; 7 : 239–242.] Zusammenfassung Eine Impetigo und Furunkulose trat bei einer Milchviehherde in Verbindung mit intensivem Abduschen bei den laktierenden Kühen während der Sommermonate auf. Färsen und trockenstehende Kühe in der selben Herde sowie die einer Nachbarherde im selben Ort, die nicht abgeduscht wurden und als Vergleichsgruppe dienten, blieben unverändert. Die Hautveränderungen reduzierten sich mit Beendigung des Abduschens. Nur sechs Tiere (drei Kühe (7, 3%) und drei Kalbinnen (20%)) mußten parenteral mit Antibiotika behandelt werden. [Yeruham, I., Elad, D., Perl, S., Nyska, A., Vishinsky, Y. Contagious impetigo in a dairy cattle herd (Ansteckende Impetigo bei einer Milchviehherde). Veterinary Dermatology 1996; 7 : 239–242.]     

中药治疗奶牛乳房炎的研究现状与展望

综述了中药治疗奶牛乳房炎的临床应用、机理和特点,认为中药治疗奶牛乳房炎采用辨证施治方法,毒副作用小且不易产生耐药性;指出了中药治疗奶牛乳房炎存在的问题,主要是基础研究薄弱、生产工艺落后、无固定标准、药品质量难以保证等.由于中药治疗奶牛乳房炎疗效确实,因而潜力巨大.     

核心群奶牛超数排卵技术影响因素的研究

[目的]为进一步研究核心群奶牛超数排卵技术影响因素。[方法]试验使用3个FSH剂量和4 个公牛精液对27头青年奶牛进行超数排卵。对供体牛胚胎生产情况和受体胚胎移植妊娠率进行统计。[结果]结果显示供体2次超排获得7.8枚平均可用胚胎显著高于1次超排获得的5.7枚平均可用胚胎(P<0.05);260,280 mg FSH超排供体获得6.0和7.7 枚平均可用胚胎显著高于300 mg FSH超排供体获得的4.6枚平均可用胚胎(P<0.05);供体使用4个公牛精液人工授精后获得的平均可用胚胎数和平均未受精卵数差异不显著(P>0.05);移植前接种疫苗的受体胚胎移植妊娠率显著降低(P<0.05）。[结论]核心群奶牛超排适宜FSH剂量为260-280 mg,使用高受精力公牛精液和对超排反应好的供体重复超排能够提高超排效率,受体移植前避免疫苗接种能够提高胚胎移植妊娠率。     

乳牛衣原体病灭活疫苗的研制

将免疫原性稳定的鹦鹉热衣原体SX5菌株灭活，加入油佐剂制备乳牛衣原体病灭活疫苗，并对疫苗的安全性进行了检测。用该疫苗对成年牛和犊牛进行了最小免疫量试验、效力试验和免疫持续期试验；结果表明，最小免疫量分别为3mL和5mL，平均免疫保护率达94．4％。免疫持续期达10个月。疫苗保存期试验表明，在4℃条件下可保存12个月。本动物安全试验和田间小试免疫证明，该疫苗安全性好，乳牛注射疫苗后饮食、产乳量及注苗部位没有明显的异常变化。     

Association between age and time from calving and reported lameness in a dairy herd in the Waikato region of New Zealand

Abstract

CASE HISTORY: During the 2014/2015 season 823 predominantly Holstein-Friesian cows calved on a pasture-based farm in the Waikato region of New Zealand. A high prevalence and recurrence rate of lameness had been noted for several years but cows feet were not routinely picked up and therapeutically trimmed.

CLINICAL FINDINGS: At a farm visit in December 2015, 23 cows feet were examined and 18/23 (78%) cows had white line disease and 17/23 (74%) sole haemorrhages, as well as severely overgrown and misshapen hooves.

EPIDEMIOLOGICAL INVESTIGATION: Lameness, culling and reproductive data were collected for the farm for the period from 01 July 2014 to 30 November 2015. In the 2014/2015 season, 207/823 (25.2%) cows were recorded lame, and in the first half of the 2015/16 season 120/850 (14%) cows were recorded lame. Of the cows recorded lame, 52/207 (25.1%) in the 2014/15 season had >1 case of lameness, and 39/120 (32.5%) cows recorded lame in the 2015/2016 season had been lame in the previous season. There was an apparent increase in prevalence between 29–37 weeks post-calving. Cows >7-years-old had seven times the odds of being recorded as lame compared to 2–3-year-old cows (p<0.001). Lameness was not associated with culling, empty rate or days to conception (p>0.3).

DIAGNOSIS: No direct cause for the lameness could be determined.

CONCLUSIONS AND CLINICAL RELEVANCE: It was hypothesised that, along with the degenerative changes in the pedal bone as dairy cows increased in age, suboptimal treatment and overgrowth of hooves resulted in permanent changes in the cows feet, resulting in a high prevalence of lameness in older cattle and a high recurrence rate of lameness within and between seasons. This case highlights the importance of prompt identification and treatment of lame cattle.     

全混合日粮对奶牛产乳性能的影响

试验选用了12头奶牛,根据产奶量、泌乳天数和胎次相近的原则分为试验组和对照组,研究全混合日粮对奶牛产乳性能的影响。试验结果表明,试验组4％标准乳产量比对照组提高1 24kg,差异显著(P<0．05),乳脂率及乳脂、乳糖和乳固形物含量也分别比对照组显著提高11．60％、17．50％、13．21％和9．86％(P<0.05)。     

单菌株与多菌株微生态制剂在提高奶牛产奶性能上的应用

文章综述了单菌株和多菌株微生态制剂在提高奶牛产奶性能上的应用,分析探讨了两种微生态制剂应用中存在的问题,并提出一些解决措施,为其进一步研究提供参考.