同期排卵处理母牛体温和活动量变化规律及效果分析

为探究同期排卵处理母牛体温和活动量变化规律及不同同期排卵技术处理效果，指导同期排卵技术优化。本研究自动监测了18头20月龄左右同期排卵（GnRH-PG-GnRH）处理荷斯坦母牛和17头产后40~60 d预同期排卵（PG-PG-GnRH-PG-GnRH）处理荷斯坦母牛的体温和活动量，应用自动检测系统进行母牛发情监测。结果发现，同期排卵处理母牛发情时阴道温度平均升高（0.43±0.20）℃，持续（12.37±2.73）h；活动量平均升高（18.28±18.61）倍，持续（11.00±1.68）h；排卵时阴道温度平均下降（0.20±0.10）℃，持续（11.00±1.68）h。自动化发情监测显示，同期排卵处理母牛7头发情并排卵；预同期排卵母牛GnRH处理前全部发情排卵。两种同期排卵处理，虽可改变母牛性周期进程，促进母牛性周期同步化，但均难以使母牛性周期完全同步。因此，将同期排卵-定时输精和发情鉴定技术科学结合才能取得更好的繁殖效果。     

宁夏地区荷斯坦牛乳房性状的遗传参数估计和主成分分析

旨在评估宁夏地区荷斯坦牛乳房性状的遗传水平。本研究使用DMU（v6.0）软件的AI-REML模块结合EM算法并配合多性状动物模型对宁夏地区12 415头荷斯坦牛，包括111 735个观察值的9个乳房性状进行遗传参数估计，运用主成分分析法（PCA）探讨构象性状之间的关系。结果表明，宁夏地区荷斯坦牛乳房性状遗传力处于中等偏低水平，乳房深度遗传力值为0.242，乳房质地为0.080，悬韧带为0.183，前乳房附着为0.230，前乳头位置为0.231，前乳头长度为0.173，后乳房高为0.272，后乳房宽为0.378，后乳头位置为0.169。各性状遗传相关范围为-0.277~0.706，表型相关范围为-0.084~0.316。研究共筛选出特征值≥1的4个主成分，占总方差的64.19%，且9个乳房性状在前3个主成分中已全部体现，荷载系数均在0.4以上。本研究通过对宁夏地区奶牛DHI数据的深入挖掘和遗传参数估计，准确地把握了宁夏奶牛群体的结构特征，对于奶牛的选种选配和育种规划具有重要意义。     

乳制品与补锌

目前我国存在一定程度的锌缺乏现象，可以乳制品为载体，有效的增加锌的吸收量。     

Cubicle refusal in Norwegian dairy herds.

In order to survey the behaviour of choosing the alley area instead of a cubicle as a lying place (cubicle refusal), a questionnaire was sent to the 273 dairy farms in Norway known to keep cows in cubicle housing systems. Sixty-six percent of the farmers contacted were included in the study. The median herd size was 18 cows (range 7-118). More than 85% of the herds had sheds providing one or more cubicles per cow. The mean herd occurrence of cubicle refusal was 6%, but showed great variation (range 0-55%). Regression analysis showed a significant association between rearing heifers in slatted floor pens and an increased cubicle refusal occurrence (p = 0.02, R2 = 0.05), while herd size, use of litter, or cubicle-to-animal ratio were not found to be associated with cubicle refusal. The practice of rearing heifers in slatted floor pens accounted for about one half of the observed cubicle refusal (etiologic fraction = 0.51).     

奶牛乳腺炎防治的免疫学和药理学机制

奶牛乳腺炎是一种复杂的多因素疾病，给世界各国奶牛业造成了巨大的经济损失，而至今未能提出一个彻底解决的办法。本文综述了奶牛乳腺炎的致病因素、乳腺的免疫机制和乳腺炎治疗的药理学机制方面的研究进展，重点剖析了乳腺特殊的免疫体系和乳腺炎治疗的药理学特点，分析阐明了奶牛乳腺炎免疫和治疗失败的原因。     

用RAPD技术筛选中国荷斯坦牛产奶量性状遗传标记

选用320条10碱基随机引物在由36头高产（305d产奶量〉8500kg）和32头低产（305d产奶量〈5600kg）中国荷斯坦牛所组成的2个DNA池间进行RAPD-PCR扩增，从中筛选出稳定性好、带型清晰且在2个DNA池间有明显差异的RAPD引物24条。用筛选到的24条引物对所有个体进行PCR检测，得到了5个与奶牛产奶量性状相关的RAPD标记，并对其中4个进行了克隆测序和SCAR标记转化以及生物信息学分析。结果表明：SCAR标记yield—s139与产奶量密切相关，应用电子克隆方法已将该标记由921bp延伸到2141bp，经同源性比较发现，此标记对应于奶牛基因组中LINEs家族中的一个重复元件，推测该元件附近可能存在与产奶量性状相关的QTLs或主效基因。     

奶牛乳房炎多联苗(B)的临床免疫试验

用奶牛乳房炎多联苗 (B)免疫家兔 ,14 d血清中金黄色葡萄球菌抗体效价可达 1∶ 8,2 8d抗体水平明显升高 ,可达 1∶ 32 ,注苗后 35 d攻毒 ,攻毒后 2 d保护率为 93.3% (14 /15 ) ,自然保护率为 2 0 % (1/5 ) ,10 d保护率为 6 6 .6 % (10 /15 ) ,自然保护率为 2 0 % (1/5 ) ;用多联苗 (B)臀部肌肉注射免疫泌乳牛 ,试验期间 4个月内 ,3ml剂量组临床型乳房炎月平均发病率为 11.0 9% ,其对照组为 2 0 .19% ,发病率降低 4 5 .2 9% ,差异极显著 (P<0 .0 1) ;5 m l剂量组月平均发病率为 13.0 1% ,其对照组为 31.36 % ,发病率降低 5 8.5 1% ,差异极显著 (P<0 .0 1) ;3ml剂量组与 5 m l剂量组之间发病率无明显差异 (P>0 .0 5 ) ;注苗后泌乳牛血清抗体水平可持续 4个月 ,且 30 d时效价水平最高。     

ULTRASONOGRAPHIC FEATURES OF DIFFUSE HEPATOCELLULAR DISORDERS IN DAIRY CATTLE

Ultrasonography of the liver was performed in 200 Holstein-Friesian dairy cattle using a 3.5 MHz transducer with a linear array electronic scanner. Liver samples were taken, processed and examined microscopically and the fat occupying rate was calculated. The hepatic ultrasonograms were evaluated according to the presence of bright pattern, dark pattern, deep attenuation, vascular blurring and blurring of edges. Of the 200 animals, 96 had a normal liver, 63 had hydropic degeneration of the liver, 37 had fatty infiltration of the liver, 3 had liver dystrophy and I had hepatic amyloidosis, diagnosed through histopathological examination. Amyloidosis was characterized by bright pattern and blurring of edges. Liver dystrophy had higher percentages of bright pattern and blurring of edges than normal liver. Hydropic degeneration had higher percentages of dark pattern and blurring of edges than normal liver. Fatty infiltration had higher percentages of bright pattern, deep attenuation, vascular blurring and blurring of edges than normal liver. The present results suggest that different ultrasonographic patterns can be observed in various diffuse hepatocellular disorders in dairy cattle     

Inflammation-related changes in cyclic AMP and cyclic GMP in bovine mastitis

Cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) cocentrations in milk and plasma samples from healthy and mastitic cows were determined by radioi-immunoassay and compared with prostaglandins (PGE2, PGF2 and thromboxane B2 [TXB2]), phospholipids and other relevant parameters in milk and blood. The concentrations of cAMP were about five times higher in plasma (p<0.01) than in milk, whereas the cGMP concentration in milk was three times higher (p<0.01) than that in plasma in both healthy and diseased animals. In mastitic milk, the cAMP and cGMP concentrations were 19% and 65% and in blood plasma 13% and 84% higher respectively than in healthy animals. In milk, cyclic nucleotide concentrations correlated with the markedly elevated cell count and also with the prostaglandin concentration and pH. In blood, cAMP correlated positively with phospholipids and cGMP with reduced glutathione (GSH). These changes are considered to be important in the disease process and, in particular, the increase in cGMP deserves further study.