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21.
Jezie A. Acorda DVM Magr Haruo Yamada DVM DVSc Seyed Mehdi Ghamsari DVM 《Veterinary radiology & ultrasound》1994,35(3):196-200
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 相似文献
22.
育肥猪舍氨气浓度测定与排放通量的估算 总被引:8,自引:2,他引:8
在北京选择一典型猪场,对不同季节育肥舍的氨气浓度进行了为期1年的试验测定,2004—2005年试验期间每2个月测定1次,每次测定3~4d,每2h采样一次,并根据二氧化碳平衡原理,对猪场不同生长阶段的育肥猪氨气排放通量进行了估算。结果表明,2005年1月舍内氨气的平均浓度为(10.09±4.60)mg·m-3。2004年7月舍内氨气平均浓度为(3.44±2.34)mg·m-3,5月舍内氨气浓度为(6.29±4.07)mg·m-3,11月舍内氨气浓度为(6.98±2.63)mg·m-3,夏季舍内氨气浓度日夜变化不显著,冬季每日最低氨气浓度出现在9:00—17:00时段;育肥猪饲养期间的氨气排放通量为每头107.18~424.42mg·h-1。 相似文献
23.
奶牛体外受精相关影响因素分析 总被引:2,自引:0,他引:2
[目的]探讨和研究奶牛体外受精(IVF)各技术环节中一些因素,对奶牛IVF整个过程的影响。[方法]研究不同来源的卵母细胞、精液的不同处理方法、不同的培养体系,不同受精时间,受精密度对奶牛IVF的影响。[结果]屠宰场采集的卵母细胞和活体采卵收集的卵母细胞的卵裂率和囊胚发育率差异不显著;对精子分别采用percoll梯度密度离心和上浮法处理,两组的卵裂率囊胚发育率无明显差异,用SOF液和BO液体外培养,两培养体系的卵裂率和囊胚发育率均差异不显著;受精时间为8、10 h及10、12 h的囊胚发育率均差异不显著,但受精8 h的囊胚发育率显著高于受精时间12 h;受精微滴(100μl)中放置成熟的卵母细胞数(20、40个),两组的卵裂率和囊胚发育率均下降,且差异显著。[结论]随受精时间的延长,卵裂率和囊胚发育率逐渐降低,差异不显著,但受精8 h的囊胚发育率显著高于受精12 h;受精微滴(100μl)中放置20个成熟的卵母细胞,可取得较好的体外受精效果。 相似文献
24.
The principle of time‐resolved fluorometry with lanthanide chelates was established in the 1980s, but in the field of animal sciences it has not been widely applied to immunoassays. However, immunoassays that utilize time‐resolved fluorometry are possible alternatives to radioimmunoassays, since they can attain high sensitivity without safety risks. In this short review, we introduce the development of time‐resolved immunoassays for inhibin A, inhibin B and follicle‐stimulating hormone (FSH), and describe their application to the investigation of FSH regulation in male and female cattle. The results obtained using these newly developed immunoassays indicate that inhibin A acts as a feedback regulator for FSH secretion in female cattle, whereas inhibin A, and probably inhibin B, do so in male cattle. 相似文献
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26.
J. Rashid D. J. Weiss S. K. Maheswaran M. P. Murtaugh 《Veterinary research communications》1996,20(6):519-531
Local and systemic activation of coagulation is frequently associated with bacterial sepsis. The coagulopathy is due, at least in part, to expression of tissue factor (TF) by monocytes and macrophages. The purpose of this study was to evaluate the expression of procoagulant activity by bovine alveolar macrophages, leukocytes and platelets, and to determine the relative potency of three chemical inhibitors of TF expression (pentoxifylline, retinoic acid, and cyclosporin A). Bovine alveolar macrophages were stimulated with lipopolysaccharide (LPS) derived from Pasteurella haemolytica or recombinant bovine tumour nervous factor (TNF) and dose- and time-dependent effects on TF expression were studied. LPS and TNF induced TF expression in alveolar macrophages and LPS treatment of whole blood induced TF expression in mononuclear cells. Neutrophils and platelets also expressed procoagulant activity, but this activity was not inhibited by anti-bovine TF monoclonal antibody. Pentoxifylline (40 mol/L), retinoic acid (0.01 mmol/L) and cyclosporin A (0.08 mol/L) inhibited TF expression when added concurrently with LPS or TNF, but not when added 4 h after stimulation. TF mRNA was not detected in unstimulated alveolar macrophages by Northern blot analysis. In contrast, exposure to LPS or TNF for 6 h induced marked expression of TF mRNA, which was inhibited by treatment with pentoxifylline, retinoic acid and cyclosporin A. Expression of TNF by alveolar macrophages stimulated with LPS was also inhibited by these compounds. Our results indicate that procoagulant activity expressed by alveolar macrophages and monocytes is associated with expression of TF, whereas procoagulant activity expressed by neutrophils and platelets is not. The concentrations of pentoxifylline and retinoic acid necessary for inhibition of TF expression in vitro may not be achievable in vivo owing to their toxic effects. However, the in vitro concentration of cyclosporin A that inhibited TF expression did not exceed the plasma concentration observed in humans, and therefore may be useful for inhibition of TF expression in vivo.Abbreviations BAL
bronchoalveolar lavage
- LPS
lipopolysaccharide
- cDNA
cloned deoxyribonucleic acid
- cAMP
cyclic adenosine monophosphate
- GAPDH
glyceraldehyde phosphate dehydrogenase
- mRNA
messenger ribonucleic acid
- TF
tissue factor
- TNF
tumour necrosis factor
- DPBS
Dulbecco's phosphate-buffered saline 相似文献
27.
北京市繁殖猪舍高温环境控制状况 总被引:5,自引:3,他引:5
高温是影响猪繁殖性能的重要环境因素。为了缓解北京市繁殖猪的热应激,于2009年对北京市猪舍的建筑类型、降温方式进行了调查,对常见猪舍外墙类型的隔热指标进行了计算评价,并对繁殖猪舍内温度进行了测试,结果表明:北京市猪舍建筑类型调查样本中,有窗封闭式、半开放式和温室大棚式猪舍的比例分别为74.0%、23.7%和2.3%;繁殖猪舍的降温方式中,通风降温和以水为媒介的降温方式各占50%左右;在现有猪舍外墙构造类型中,外贴聚苯板内砌砖的复合墙体的隔热性能最好。北京市夏季繁殖猪舍内温度与舍外变化趋势基本一致,多数时间内舍内温度高于舍外。最后,提出北京市目前繁殖猪舍的高温环境调控建议。 相似文献
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近年来,大通县按照县委、县政府制定的实施意见、发展思路和规划,把畜牧业作为"牧业增效、农民增收"为奋斗目标。调整畜牧业内部结构,优化区域布局,逐步建立和发展奶牛、肉牛养殖生产基地。进行专业化生产,规模化经营,科学化饲养,转变传统养殖观念,逐步树立现代科学养殖观念,大力发展奶牛、肉牛等一批优势主导产业,逐步建立奶牛、肉牛养殖生产基地,推动全县畜牧业的快速发展。本文对大通县养牛业发展现状进行了详细分析,并对今后的发展思路进行了探讨。 相似文献