利用耳组织、血液、牛奶样品检测牛病毒性腹泻病毒的比较

牛病毒性腹泻病以发热、口腔及消化道粘膜糜烂、腹泻为主要症状,可引起怀孕母牛流产或产畸型胎儿,给养牛业造成巨大的经济损失,该病已成为当前严重危害我国养牛业的传染病之一。由于大部分感染BVDV的牛不表现特征性的临床症状和病理变化,而且引起腹泻和消化道黏膜糜烂或溃疡的疾病很多,所以确诊需进行实验室检查。目前实验室检测BVDV的主要方法是利用美国IDEXX公司ELISA诊断试剂盒,通过BVDV抗原和抗体的检测区别牛群持续感染牛。用于检测BVDV的样品种类有许多种,绝大多数是采集血液(血清)或牛奶样品进行检测。本试验对奶牛进行耳组织采样,同时采集血液和牛奶,用三种样品在相同条件下同时检测BVDV抗原,用血清和牛奶样品检测抗体,比较样品的检测结果。结果表明,这三种样品检测结果具有一致性,且耳组织采样更宜于大面积筛查。     

干旱对草坪草的影响

综述了干旱条件下草坪草的生态适应性,细胞膜、细胞壁、叶绿体超微结构的变化,草坪草对干旱胁迫的生理生化反应,以及提高草坪抗旱性的途径。     

对耕地保护的认识和思考

耕地保护的落实关系到我国的粮食安全,经济安全,生态安全。为了能够对耕地保护有一个更好的认识,文章从耕地保护的提出、目标、意义、主体、策略等方面来再次的认识耕地保护,耕地保护需要政府、农民以及其他非耕地使用者的共同参与,并提出了进一步建立和完善耕地保护的经济补偿机制,充分调动农民对保护耕地的积极性,明确耕地产权的耕地保护策略。     

用线锯截胎治疗母牛难产的探讨

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。     

调整内部结构 迎接挑战 使危机变为发展的商机——专访广东恒兴集团副总裁蒋洪斌

记者：金融危机对整个行业来说是一种挑战和机遇,请您谈谈在金融危机的影响下,恒兴是如何保证利润和扩大市场占有率的？     

Immune responses and protective efficacy of a recombinant swinepox virus co-expressing HA1 genes of H3N2 and H1N1 swine influenza virus in mice and pigs

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.     

Tembusu virus infection in Cherry Valley ducks: The effect of age at infection

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.     

1月份全国饲料生产情况分析

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。     

2009年7月全国饲料生产形势分析

1 全国总体概况 7月份．全国饲料总产量同比和环比均略有增长．浓缩饲料和添加剂预混合饲料产量环比下降．尤其添加剂预混合饲料降幅较大。根据对全国30个省（自治区、直辖市）166家饲料企业的调查显示,总产量为315．0万t,同比上涨2．2％,环比上涨0.3％（表1）。