牛乳电导率和pH值变化与体细胞数相关性的研究

本试验以随机采集的奶牛乳样为研究对象,对乳样的电导率、pH值与体细胞数进行了测定与分析。结果显示,体细胞数在50万个／mL以下时．电导率值在4．40～4．75ms／cm之间、pH值在6．50～6．80之间;体细胞数在50万-500万个／mL以上时．电导率在5．20～9．00ms,cm之间、pH值在6．80～7．20;体细胞数在500万以上,电导率值在9．00ms／cm以上、pH值在7．20以上。结果表明,牛乳电导率的变化与体细胞数呈正相关,pH值的变化与体细胞数相关性不明显,可利用牛乳体细胞数与电导率变化的相关关系判断奶牛隐性乳房炎发病程度。     

初产母牛泌乳早期体细胞计数对其泌乳全期体细胞计数的影响

比利时根特大学的科研人员研究了初产母牛泌乳早期(5-14d)乳中体细胞计数(SCC，下同)对其初次泌乳全期的SCC的影响。在14766个样品中，其平均SCC为104000细胞／ml。体细胞计数由泌乳第5天的178000下降剖第14天的74000细胞／mL。其中大于200000细胞／mL的样品数占27．5％。     

本细胞数与乳成分、胎次、产奶量及季节之间关系的研究

本试验分析了15000头（次）奶牛所产原料奶样本，比较了体细胞数与乳成分、胎次、305天产奶量及季节之间的关系。结果表明：随着体细胞数的升高，乳脂率、乳蛋白率、乳糖率逐渐降低。当体细胞数为50万～100万个／mL时，原料奶中总固体及非脂乳固体含量达到最高；当体细胞数超过100万个／mL时，总固体含量开始下降。随着体细胞数的增加，冰点逐渐增加，但各组差异不显著。随着胎次的增加，体细胞数逐渐增加。随着体细胞数的增加，产奶量逐渐下降。夏季、秋季的体细胞数比春季、冬季的高，夏季、秋季与春季、冬季体细胞数相比差异显著。     

牛乳电导率值与体细胞数相关性的研究

试验以随机采集的奶牛乳样为研究对象，对乳样的电导率值与体细胞数进行了测定与分析。结果显示，体细胞数在50万个/ml以下时，电导率值在4．40～4．75ms／cm之间；体细胞数在50万～500万个／ml时，电导率值在5．20～9．00ms／cm之间；体细胞数在500万／个ml时，电导率值在9．00ms／cm以上。结果表明，牛乳电导率的变化与体细胞数呈正相关，可利用牛乳体细胞数与电导率变化的相关关系判断奶牛隐性乳房炎发病程度。     

创造新鲜 创新生活——巴氏杀菌鲜奶论坛研讨会讲话摘录—我们的鲜奶

三元集团和北京市奶业协会对产品质量历来比较重视．协会和集团领导对奶业的发展具有前瞻性的眼光。三元集团从1998年开始执行原料奶收购按质论价体系．将乳蛋白、乳脂肪含量以及微生物数量纳人计价体系。1999年．首先把抗生素残留纳入计价体系。从2001年开始，把体细胞数纳入计价体系；2002年，开始在内部研究第三方检测的问题．体细胞数以60万个／mL为标准．高于60万个／mL的要罚款．低于60万个／mL的给予奖励：现在叉再次将标准细分为6级。将体细胞数纳入计价体系，     

创造新鲜 创新生活——巴氏杀菌鲜奶论坛研讨会讲话摘录—协会和企业是原料奶质量监控体系的主体

从我国对原料奶的质量监控体系建设上来看，协会和企业应该是主体。但是。我个人认为。更重要的是国家和政府应该有所作为，应该发挥更重要的作用。中国奶业的发展需要具备与国际接轨的标准．特别是必须要明确原料奶的收购标准，并且要制定相应的立法。从2001年开始。北京三元集团存原料奶的收购方面将体细胞数与原料奶质量挂钩。三元绿荷奶牛养殖场全年原料奶中的平均体细胞数拧制在27万个／mL以下，细菌数控制在5万个／mL以下。     

隐性乳腺炎患牛乳汁电导率变化与体细胞数相关关系的研究

本试验以随机采集的奶牛乳样为研究对象,对乳样的电导率与体细胞数进行了测定与分析。结果显示,体细胞数在20万～50万个/mL时,奶牛乳汁电导率值在0.40～0.55mho/m之间;体细胞数在50万个/mL以上时,奶牛乳汁电导率在0.6mho/m以上。结果表明,牛乳电导率的变化与体细胞数呈正相关,可确定利用牛乳体细胞数与电导率变化的相关关系可准确判断奶牛隐性乳房炎。     

凉山钢鹅血液常规指标的测定

本试验测定了四川白鹅、凉山钢鹅、川凉鹅和凉川鹅的血液常规指标，结果表明：试验鹅的血红蛋白11．16－12．99g/100mL，红细胞数为315．0－333．0万个／μL，白细胞数为30600－32000个／μL，血小板数为17．9－18．5万个，血沉率为1／15、2／30、3／45、4／60mm，嗜酸性白细胞3．80％－4．50％，嗜碱性白细胞2．30－2．50％，嗜中性白细胞35．80％－36．10％，淋巴细胞52．50％－53．40％，单核细胞为4．20％－4．50％。     

嗜酸乳杆菌对胃肠道酶的敏感性研究

以MRS为培养基，模拟胃肠环境对嗜酸乳酸茵对pH、胃蛋白酶、胰蛋白酶、胆汁盐的敏感性进行了研究。结果表明：在pH1．60～5．00、温度37℃，胃蛋白酶0．592ug／mL-1．4821μg／mL条件下，活茵数能达到108cfu/mL以上。在MRS培养基自然pH条件下，胰蛋白酶活力在14．24u／g-72．32u／g范围内，胆汁盐0．2％的情况下，活茵数能达到107cfu／mL以上。证明了嗜酸乳酸茵能顺利通过胃肠环境，促进人体健康。     

体细胞数与乳成分、胎次、产奶量及季节之间关系的研究

本试验分析了15000头(次)奶牛所产原料奶样本,比较了体细胞数与乳成分、胎次、305天产奶量及季节之间的关系。结果表明:随着体细胞数的升高,乳脂率、乳蛋白率、乳糖率逐渐降低。当体细胞数为50万~100万个/mL时,原料奶中总固体及非脂乳固体含量达到最高;当体细胞数超过100万个/mL时,总固体含量开始下降。随着体细胞数的增加,冰点逐渐增加,但各组差异不显著。随着胎次的增加,体细胞数逐渐增加。随着体细胞数的增加,产奶量逐渐下降。夏季、秋季的体细胞数比春季、冬季的高,夏季、秋季与春季、冬季体细胞数相比差异显著。     

益康XP对奶牛血浆内毒素含量及其他指标的影响

选取泌乳天数<40 d的健康奶牛 12头,按胎次、泌乳天数和产奶量相同或相似的原则,分为试验组和对照组。两组日粮组成相同,试验组牛每天添加益康XP的剂量为试验第1天至第7天500 g/(头·d),从第 8 天后减少到120 g/(头·d),分两次饲喂。试验期为60 d。于试验前 1 天,试验第 20 天,40天和第 60 天分别采血,用鲎试剂法测定血浆内毒素含量;定期测定日均产奶量、乳脂率、乳蛋白率和体细胞数;记录情期受胎率及疾病发生情况。结果表明,试验组奶牛在试验后第20天,第 40 天和第 60 天血浆内毒素均极显著低于对照组(P<0.01);产奶量在第20天,第60天显著高于对照组(P<0.05);两组奶牛乳脂率、乳蛋白率、体细胞数差异均不显著(P>0.05);试验组情期受胎率极显著高于对照组(P<0.01);在疾病发生率方面,试验组极显著低于对照组(P<0.01)。     

Relationship between milk production and somatic cell count in dairy cows in East Gippsland

SUMMARY The analysis of records for 75 821 herd tests on 23 700 cows in the Macalister Irrigation District of East Gippsland, using a model that also included stage of lactation, herd and cow effects, found a strong relationship between somatic cell count and milk production. Unit increases in the natural logarithm of the somatic cell count were associated with decreases in production of up to 2.6% in the range 54 598 to 403 429 cells per mL. This is equivalent to a decrease of 1.9% for a doubling of cell count from 100 000 to 200 000 cells per mL. Subclinical mastitis was assessed to be a significant source of loss in milk production in the study area.     

Somatic cell counts, mastitis and milk production in selected Ontario dairy herds.

Somatic cell counts were performed monthly on bulk tank milk samples for all producers in the Ontario counties of Hastings, Lennox/Addington and Prince Edward throughout 1978 and 1979. Other data were obtained via a structured questionnaire and from the records of the Ontario Milk Marketing Board. Many producers have not adopted practices that have been advocated for the integrated control of mastitis. For example, 43.3% of producers surveyed used single service paper towels, 63.3% regularly used teat dip and 56.5% dry cow therapy. The mean of the average monthly somatic cell count for all producers for 1978 was 621.1 x 10(3) cells/mL. This latter value was used to divide the producers into case (higher than average) and control (lower than average) groups. Control herds averaged 95.9 liters more shipped milk per cow per month than case herds. Milk from control herds averaged 0.22 percentage points higher than case herds for each of average fat and lactose, and 0.16 percentage points higher for protein. The linear regression of monthly shipped milk on the respective monthly bulk tank somatic cell count indicated a loss of 13.26 L/cow/month for each 100,000 increase in somatic cell count.     

消炎泌乳冲剂对隐性乳房炎奶牛血清中IL-8、TNF-α的影响

 选择无乳房炎临床症状且乳汁检测体细胞数大于50万/mL, CAM检测阳性的奶牛60头,依据年龄、胎次相同,泌乳日相似（产犊日期在5d以内）,产奶量和泌乳期相近的原则进行配对分组。治疗组用消炎泌乳冲剂300~400g 头/d,对照组不用药。结果表明：消炎泌乳冲剂可以使乳房炎奶牛血清中的IL-8、TNF-α的含量显著降低,用药后14 d, IL-8的含量与试验前和对照组比,分别降低0.194 ng/L和0.198 ng/L,差异显著(P<0.05）,用药21 d分别降低0.263 ng/L和0.253 ng/L,用药30 d分别降低0.268 ng/L和0.239 ng/L,差异极显著（P<0.01）;TNF α含量在用药14 d、21 d和30 d与试验前相比,分别降低0.33 ng/L、0.459 ng/L和0.646 ng/L,差异极显著（P<0.01）,和对照组比分别降低0.372 ng/L、0.504 ng/L和0.678 ng/L,差异极显著（P<0.01）。乳汁中的体细胞数在用药后14 d极显著下降 (P<0.01), 21 d时下降到50 万/mL以下,到120 d时一直维持在正常水平内。治疗组奶牛在试验期间每头牛的日产奶量比对照组提高10.98%(P<0.05),停药后3个月对照组日产奶量比治疗组降低了39.97%（P<0.01）。受试奶牛乳脂率和乳蛋白没有显著性变化。     

添加不同浓度黑曲霉菌液对饲用苎麻混合青贮品质影响

为了解决苎麻（Boehmeria nivea）木质纤维素含量过多的问题,本试验设计了4个处理,在每千克混合青贮（80%苎麻+18%麦麸+2%蔗糖）中添加不同浓度的黑曲霉（Aspergillus niger）菌液（添加50 mL黑曲霉菌液+150 mL无菌水为处理Ⅰ、添加100 mL黑曲霉菌液+100 mL无菌水为处理Ⅱ、添加150 mL黑曲霉菌液+50 mL无菌水为处理Ⅲ、添加200 mL黑曲霉菌液为处理Ⅳ、添加200 ml无菌水为对照组（CK））,发酵30 d后开包取样分析各项指标。结果显示,添加黑曲霉菌液显著提高了青贮中可溶性碳水化合物、干物质、乳酸和乙酸含量（P<0.05）,显著降低了青贮中pH和氨态氮/总氮比值（P<0.05）;处理Ⅱ、处理Ⅲ和处理Ⅳ组显著降低了青贮中中性洗涤纤维、酸性洗涤纤维及酸性不溶木质素含量（P<0.05）;对处理Ⅱ组样品进行酶活检测发现,随着发酵时间的延长,羧甲基纤维素酶、锰过氧化物酶、漆酶和木聚糖酶4种酶酶活都有不同程度降低。从节约成本角度考虑,处理Ⅱ组是进行木质纤维素降解、青贮品质提高的最佳处理。     

复方中草药灌注液治疗奶牛子宫内膜炎临床效果观察

目的 研究旨在通过试验观察中草药治疗奶牛子宫内膜炎疗效,以其为临床应用中草药治疗奶牛子宫内膜炎提供参考。方法 将60 头患子宫内膜炎奶牛,随机分成5 组,每组12 头,复方中草药高、中、低剂量组（分别子宫灌注150 mL/头、100 mL/头和50 mL/头）、土霉素组（子宫灌注50 mL/头）和对照组。结果 复方中草药中剂量组和高剂量组的总有效率为75.00%和83.33%,均高于土霉素组的总有效率66.67%;土霉素组在治疗结束后的平均发情天数缩短了14 d,所有复方中草药组的发情天数也缩短了11~19 d;3 个情期内土霉素组受胎率为50.00%,复方中草药组受胎率介于41.67%~66.67%之间。结论 复方中草药对奶牛子宫内膜炎的治疗效果优于土霉素,其中以高剂量组效果最佳。     

Effect of treatment with an internal teat sealant at drying-off in cows wintered on forage crops in New Zealand on clinical mastitis and somatic cell counts

AIMS: To determine the impact of treatment with internal teat sealant (ITS) compared to no treatment at drying-off on the incidence of clinical mastitis (CM) during the dry period and 84 days after calving, and the prevalence of cows with somatic cell counts (SCC) ≥200,000?cells/mL at the first lactation herd test, for cows wintered on forage crops.

METHODS: In four dairy herds in the South Island of New Zealand, cows with no history of CM or individual SCC >100,000?cells/mL during the 2015–16 season were randomly assigned to treatment with ITS in each quarter (ITS group) at drying-off or no treatment (Control group). Cows were otherwise treated similarly, wintered on forage crops and transferred to pasture for calving and lactation. Cows were monitored over the dry period and for 84 days after calving, and any case of CM recorded. Individual SCC were recorded at the first herd test after calving.

RESULTS: Between drying-off and 84 days after calving 36/470 (7.7%) cows in the ITS groups and 73/442 (16.5%) cows in the Control group were diagnosed with CM (RR=0.46; 95% CI=0.26–0.73). The final multivariable logistic regression model included an interaction between treatment group and length of dry period. For a Friesian/Jersey cow, aged 4–8 years, with a dry period of 30–80 days, dried off without ITS, the probability of CM in the study period was 0.12 (95% CI=0.09–0.16), and for such a cow treated with ITS the probability was 0.07 (95% CI=0.05–0.10). For an equivalent cow, with a dry period of 81–140 days, which was untreated, the probability was 0.21 (95% CI=0.14–0.29), and for such a cow treated with ITS it was 0.05 (95% CI=0.02–0.11). At the first herd test after calving 77/383 (20.1%) cows in the Control group and 57/425 (13.4%) cows in the ITS group had SCC ≥200,000?cells/mL (RR=1.51; 95% CI=1.10–2.06).

CONCLUSIONS AND CLINICAL RELEVANCE: For these farms, treatment of cows with no history of elevated SCC or CM with ITS at drying-off halved the incidence of CM between drying-off and 84 days after calving, and reduced by 33% the proportion of cows with SCC≥200,000 at the first herd test after calving, compared with untreated cows. Treatment with ITS reduced the risk of CM proportionally more for cows with a dry period of 81–140 days than for cows with a shorter dry period.     

The use of toltrazuril for the prevention of coccidiosis in piglets before weaning

SUMMARY: To determine the efficacy of toltrazuril as a prophylactic treatment for coccidiosis in piglets caused by Isospora suis (I suis) , a single 1.0 mL dose of toltrazuril was administered orally to 1056 piglets between 3 and 6 days of age, in 5 piggeries. Prophylactic treatment of piglets reduced the occurrence of coccidiosis in litters from 71% to 22%. The number of antibacterial treatments given and the number of piglets affected per litter were also significantly reduced, resulting in some improvement in growth rates to weaning. The severity of diarrhoea was significantly reduced, as was the amount of oocyst excretion. The number of days that piglets excreted oocysts in the faeces was reduced from 4.9 days to 2.5 days. The detection of J suis in piglets with diarrhoea was reduced from 84% in the untreated piglets to 6% in the piglets given the prophylactic treatment.     

Relationship between test-day measures of somatic cell count and milk production in California dairy cows.

The relationship between test-day measures of milk somatic cell count and milk yield was evaluated using the November 1985 test data from 8352 Holstein cattle (2923 primiparous and 5429 multiparous cows) located in ten Tulare County, California dairies. Following correction for herd and stage of lactation effects, design variable regression was used to create separate models for primiparous and multiparous cows predicting the changes in milk production associated with milk somatic cell count class. Cell counts were stratified by 1/2 loge cell count (x1000 cells/mL) units, permitting comparisons with previous studies. Cell counts less than 148,000/mL were not found to be associated with significant reductions in milk yield when compared to the reference class (cell counts less than 20,000/mL). Consistent incremental decreases in milk production were not noted with increasing cell count strata, even following the natural log transformation. The most dramatic production losses were noted in the range of 148,000 to 665,000 cells/mL. Primiparous cattle in the 403,000 to 665,000 cell count strata experienced a 5.22 kg (19.72%) decrease in test-day milk yield. Multiparous cattle in the same class experienced 3.01 kg (7.82%) reductions in milk production. Primiparous and multiparous cows had similar production losses. The study population differed from previous studies on the basis of herd size, milk production and the level of udder health, measured by milk somatic cell count. These differences and the choice of experimental design may in part explain differences in study results and conclusions.     

利用乳汁体细胞研究共轭亚油酸钙对奶牛乳腺基因表达的作用

8头泌乳中期的奶牛被随机分为2组，分别是对照组（每头牛：基础日粮＋棕榈酸钙200g／d）和试验组（每头牛：基础日粮＋共轭亚油酸钙200g／d），试验期14d，检测了奶产量、乳成分，分析奶牛的血液变化，并采用荧光定量PCR对乳汁体细胞中脂蛋白脂酶（LPL）、乙酰辅酶A羧化酶（ACACA）的基因表达进行检测。结果显示，与对照组相比，试验组奶牛的乳产量、乳蛋白、乳糖和乳汁体细胞含量没有显著影响，但是显著降低了乳脂肪含量（P〈0．05），对照组和试验组奶牛乳脂肪含量分别为0．0326g／mL和0．0244g／mL。检测血液指标发现，共轭亚油酸钙显著升高了奶牛血液中高密度脂蛋白的含量（P〈0．05）。基因分析发现，试验组奶牛乳汁体细胞中LPL、ACA—CA的基因表达显著下调，表明共轭亚油酸钙抑制了奶牛乳腺细胞脂肪酸合成酶的基因表达。