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121.
动物产地检疫是指动物离开饲养地之前所实施的检疫,即到场到户进行的检疫,是整个动物检疫工作的基础,是防止患病动物进入流通环节的关键,是促进动物疫病预防工作的重要手段。这项工作开展的程度如何,直接影响到畜牧业的健康发展和 相似文献
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124.
研究了不同低压下喷头喷嘴直径和喷嘴锥角对射流破碎的影响。采用高速摄像仪对低压圆柱射流的射流核心长度和射流破碎长度进行实验,测量了不同喷嘴结构的流量、射程和末端水滴直径。结果表明:同一压力下,当喷嘴锥角不变时,随着喷嘴直径的增大,喷头流量、射程和喷头末端水滴直径都变大,射流核心长度和破碎长度均增大;当喷嘴直径不变时,随着喷嘴锥角的增大,喷头流量逐渐减小,而喷头射程呈先增大后减小趋势,喷头末端水滴直径也变大,射流核心长度逐渐减小,射流破碎长度先减小后增大。综合考虑射程和雾化效果,直径为5 mm、锥角为45°的喷嘴为最优选择。同时通过对不同Re数和We数的实验和分析,给出了适合低压喷嘴的两种射流特征长度的拟合关联式。 相似文献
125.
近年来,一些危害人类生命健康的重大动物源性食品安全事件不断发生,如发生在比利时的二恶英事件,英国的疯牛病事件,日本的大肠杆菌0157污染事件以及禽流感疫情等。食品安全已成为一个日益引起关注的全球性热点问题。建立以风险分析为基础的标准体系,推行动物源性食品安全科学的管理模式。 相似文献
126.
小肽营养素对奶牛泌乳性能的影响 总被引:31,自引:0,他引:31
试验选择泌乳期中国荷斯坦奶牛32头,随机分为4组,A组(对照组)为基础精料日粮组;B、C、D组分别为基础精料日粮 0.1%、0.3%、0.5%小肽营养素。正试期28d。结果表明,添加0.1%、0.3%、0.5%小肽营养素后,奶牛头日平均产奶量分别提高1.67kg(6.38%)(P<0.05)、1.75kg(6.69%)(P<0.05)和1.64kg(6.27%)(P<0.05)。添加小肽营养素后,乳蛋白和乳脂率均有所提高,其趋势随小肽营养素添加量的增加而提高。添加0.1%、0.3%、0.5%小肽营养素后,奶牛头日净增效益3.52元、3.40元、2.86元。综合生产性能和经济效益,以添加0.1%-0.3%小肽营养素为适宜。 相似文献
127.
Four hundred male chickens were selected to study the effects of pyruvate (Pyr), creatine pyruvate (CrPyr) and creatine (Cr) on the expression of hepatic mitochondrial and cytoplasm proteins associated with lipid and protein metabolism. Mitochondrial purification was accomplished using the two-step differential centrifugation and density gradient method, and the activities of organelle-specific marker enzymes were determined to assess the purity of the mitochondria. Proteins were extracted and fractionated by two-dimensional electrophoresis and the differential protein spots were assessed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry. CrPyr reduced fatty acid accumulation by down-regulating adipose differentiation-related protein, inhibited ATP synthase expression, and reduced cholesteryl ester transfer protein (CETP) expression, thus reducing the levels of high density lipoprotein and triglycerol (TG) levels (thereby lowering fat and cholesterol deposition). CrPyr increased the expression of eukaryotic translation initiation factor (eIF) 2B, calreticulin (CRT) and eIF3a, thus promoting protein synthesis. CrPyr up-regulated the expression of fatty acid-binding proteins, CETP and apolipoprotein A-IV in cytoplasmic extracts, and these proteins accelerated the decomposition of fatty acids and TG, thus reducing fat deposition. In conclusion, CrPyr plays an important role in lipolysis and protein synthesis, and this effect was more pronounced than was the effect of Pyr and Cr. 相似文献
128.
C.C. Chiang C.J. Chang H.C. Peh S.E. Chen B. Yu M.T. Chen H. Nagahata 《Veterinary immunology and immunopathology》2010,133(2-4):125-132
Polymorphonuclear neutrophils (PMN), which comprise over 70% of the somatic cells in goat milk, are a major cellular component of innate immunity in the goat mammary gland. However, the function of milk PMNs is modified after diapedesis compared to PMNs in blood. As many aspects of PMN activity depend directly on intracellular Ca2+ concentration ((Ca2+)i), the present study aimed to determine the changes in Ca2+ homeostasis of milk PMNs from lactating goats compared to autologous blood PMNs, and to examine the significance of these variations to the immuno-competency of milk PMNs. The intracellular Ca2+ store of freshly prepared milk cells was estimated from the elevation of (Ca2+)i after ionomycin treatment, which was found to be significantly less than blood PMNs. Replenishment of the intracellular Ca2+ store in milk cells after intracellular Ca2+ depletion by Bapta-AM followed by spiking with 2.5 mM Ca2+ for 20 min was also compared to that of blood PMNs, showing that after depletion/spiking the intracellular Ca2+ store in milk cells was much less than blood PMNs. The production of superoxide anion (O2?) in vitro in response to (Ca2+)i-dependent or (Ca2+)i-independent modulators was used to evaluate the relevance of altered Ca2+ homeostasis on the immuno-competency of milk cells compared to blood PMNs. The results indicated that milk cells produced similarly low levels of O2? as blood PMNs when treated with ionomycin. However, the amount of O2? produced by milk cells in response to phorbol 12-myristate 13-acetate (PMA) stimulation, although greater than ionomycin treatment, was significantly less than that of blood PMNs. The capacity for O2? production by both cell types in response to PMA reverted to the resting state with use of the protein kinase C (PKC) inhibitor, staurosporine. In conclusion, the current study demonstrated an irreversible shortage of intracellular Ca2+ in the milk PMNs of lactating goats compared to blood PMNs. It also showed that preliminary O2–production, primed by ionomycin treatment, remained unchanged in milk PMNs, despite the shortage in intracellular Ca2+, but decreased O2? production capacity, mediated via the PKC pathway, in milk PMN. It is suggested that the defects in Ca2+ homeostasis in milk PMNs of lactating goats is partially attributable for the post-diapedesis functionality modifications. 相似文献
129.
为了了解和掌握我市猪场的猪瘟免疫情况及感染高致病性禽流感疫病的可能性,我所分别于2005年2月和4月两次对全市范围内各类型的养猪场免疫猪瘟的猪只采集血清941份,进行猪瘟血清抗体监测和猪高致病性禽流感疫情血清学监测。现将监测结果报告如下。 相似文献
130.
[目的]掌握安徽省规模猪场高致病性蓝耳病的感染状况和免疫抗体水平。[方法]采用抗体阻断ELISA、荧光RT-PCR方法检测了24个猪场的588份血清样本和28个场点的790份组织样品。[结果]高致病性蓝耳病个体抗体免疫合格率为78.1%,群体免疫合格率为75.0%;中型猪场的平均免疫抗体合格率为87.1%、小型猪场为63.9%。高致病性蓝耳病病毒核酸个体阳性率为28.7%,群体阳性率为75.0%;中型猪场、小型猪场和生猪屠宰场的高致病性蓝耳病病毒核酸个体阳性率分别为41.7%、19.5%和6%。[结论]2015年安徽省规模猪场的高致病性蓝耳病抗体免疫合格率较高,但存在带毒现象,建议加强疫病的免疫和综合防控。 相似文献