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71.
72.
牛难产在兽医临床上是一种较常见的产科病,它是由于分娩过程中出现了某些异常情况,如产畜骨盆狭窄,子宫或阴道结构异常或产力不足导致胎儿不能正常产出的疾病,在实际生产中因胎儿过大、双胎以及胎势异常等情况造成的难产常有发生,往往因救治不当或救治不及时引起不孕、生产截瘫,甚至造成母子双亡的现象也经常发生,给广大养殖户造成严重的经济损失。 相似文献
73.
不同的干燥工艺对荷花蜂花粉功能成分的影响 总被引:1,自引:0,他引:1
探讨了5种干燥工艺对荷花蜂花粉功能成分的影响。微波干燥的干燥效率最高,60%火力处理540s可使水分从31.41%降到6.42%;干燥方式对荷花蜂花粉蛋白质影响较小;微波干燥后总黄酮提取率最高,为13.20mg/g;真空冷冻干燥后维生素C和过氧化氢酶含量最高,分别为48.89mg/100g和29.86mg/g·min。总的来说,真空冷冻干燥对荷花蜂花粉的功能成分影响最小;常压恒温干燥对功能成分影响较小、工艺简单、对设备要求低,宜于大规模应用于实际生产中。 相似文献
74.
Jiarong Xu Dongyan Huang Jiaping Xu Shichao Liu Huixing Lin Haodan Zhu Bao Liu Wen Chen Chengping Lu 《Veterinary microbiology》2013
The recombinant swine poxvirus rSPV/H3-2A-H1 co-expressing HA1 genes of H3N2 and H1N1 subtype SIV has been constructed and identified. Inoculations of rSPV/H3-2A-H1 yielded ELISA and neutralization antibodies against SIV H1N1 and H3N2, and elicited potent H1N1 and H3N2 SIV-specific INF-γ response from T-lymphocytes in mice and pigs in this study. Complete protection against SIV H1N1 or H3N2 challenge in pigs was observed. 相似文献
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Three groups of Cherry Valley ducks at 5 day, 2 week and 5 week of age were intranasally infected with the WFCL strain of Tembusu virus (TMUV) to investigate the effect of host age on the outcome of TMUV infection. For each age group, clinical signs, gross and microscopic lesions, viral copy numbers in tissues and serum neutralizing antibody titers were recorded. Age-related differences in the resistance to TMUV infection were observed with younger ducks being more susceptible. Some ducks infected at 5 day and 2 week of age developed severe clinical signs, including severe neurological dysfunction and death. However, subclinical signs and no mortality were observed in ducks infected at 5 week of age. A decline in the severity of gross and microscopic lesions was observed as ducks mature. Systemic infections were established in the three age groups post challenge. Higher viral copy numbers in the tissues, especially in vital organs such as the brain and the heart, were developed in the ducks infected at 5 day of age than older ducks, correlating with the severity of clinical signs and lesions in the tissues. Furthermore, ducks infected at 5 week of age developed significantly higher serum neutralizing antibody titers than ducks infected at 5 day of age as determined by serum neutralization test. Therefore, age-related differences in the resistance to TMUV infection should be considered when studying the pathogenicity, pathogenesis, formulation of the vaccination and therapy strategies of TMUV infection in ducks. 相似文献
77.
2006年1月份抽查筛选了29个省份124家饲料企业,总产量100.6万t,同比下降5.39%,环比下降16.90%。其中配合饲料74.3万t.同比下降7.84%,环比下降17.50%;浓缩饲料22.1万t,同比增长2.48%,环比下降13.87%;复合预混料4.2万t.同比增长1.12%,环比下降21.29%。配合饲料、浓缩饲料和复合预混料产量与往年同期产量情况见表1。 相似文献
78.
XU Li-pu WANG Xiao-liang ZHANG Wen PAN Yong JING Hong-li WANG Jing-bo WANG Shu CAO Huan WANG Peng NA Li-hai JIANG Yu-lin 《中国畜牧兽医》2017,44(2):613-618
An acute infectious diseases occurred in a koi farm in Fangshan district, Beijing, and it resulted in mortalities of more than 50%.The main symptoms of sick koi were gills necrosis, kidney erosion and edema,which were similar to the clinical signs of koi herpes virus disease (KHVD).But PCR tests showed negative results for KHV. For further diagnosis, bacterial cultures, transmission electron microscopy studies, virus isolation and PCR tests were used. Electron microscopic observation revealed pox virus particles having a size of about 200 nm×400 nm in the kidney. 548 and 180 bp fragments were amplified from organs of sick koi by PCR method using specific primers of carp edema virus (CEV). The fragments were sequenced and analysed. The results showed that they were shared 100% nucleotide identity with CEV-H504. All the results indicated that this disease was carp edema virus disease, caused by a kind of pox virus, CEV. This was the first report on the CEV of cultured koi in China. 相似文献
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