Evaluation of immunogenicity and protective efficacy of Actinobacillus pleuropneumoniae HB04C(-) mutant lacking a drug resistance marker in the pigs

Previously, we reported the construction and characterization of a genetically defined Actinobacillus pleuropneumoniae (A. pleuropneumoniae) apxIIC gene mutant, HB04C(-), which conferred protection to mice against infection with A. pleuropneumoniae. In this study, we further evaluated HB04C(-) for safety and its ability to elicit protective immunity in pigs. It was demonstrated that a dose of 2 x 10(8) CFU HB04C(-) was safe to the pigs via intranasal or intramuscular injection. Immunization with a dose of 2 x 10(8) HB04C(-) by both intranasal and intramuscular routine could yield equal protective efficacy and elicited significant protection against experiment challenge with homologous or heterologous serotypes of a virulent A. pleuropneumonia. Taken together, HB04C(-) might serve as a promising vaccine candidate against infection with A. pleuropneumoniae.     

企业如何实现零呆帐销售?

所谓零呆帐销售是一种与时俱进确保企业盈利的营销策略,也是一种追求“机会最大化,风险最小化”的营销战术,更是一种讲究“销前预防、销中控制、销后催款”的企业文化,这是摆脱“冒险销售”这个紧箍咒的最好办法,能够帮助企业百分之百收回应收帐款,保证利润百分之百落地生根变呆帐为零。     

湖南省动物疫情测报站的作用与管理

湖南省根据地理区域和养殖业结构情况,合理布局建立了18个省级动物疫情测报站,通过对测报站辖区内及定点养殖场户的生产、免疫、疫病等情况进行持续跟踪调查和监测采样,评估动物群体免疫状态及疫情发生风险。管理上通过优化网络布局,提高诊断监测能力,通过强化培训和责任管理,提升动物疫情测报水平,确保了动物疫情测报质量。动物疫情测报站在发现新发重大动物疫病,评价强制免疫病种免疫效果,提供疫情预警预报基础数据以及指导养殖业生产等方面发挥了重要作用。今后需持续增加投入和监测科技含量,改善设施设备,稳定技术队伍,这是提高动物疫情测报监测的根本保障。     

不同采毛方式对长毛兔血清蛋白及含氮代谢物水平的影响

文章分析了3种方式（剪毛、直接拔毛和药物拔毛）对皖系长毛兔采毛前、采毛后0、4、8、24、48 h血清蛋白及含氮代谢物变化规律的影响.结果发现：3种采毛方式均显著上调血清总蛋白和肌酐水平,而血清白蛋白仅受药物拔毛影响而显著上调;药物拔毛显著上调血清总胆红素和直接胆红素水平,同时直接胆红素还受其他两种采毛方式影响而显著下调;两种拔毛方式（直接拔毛和药物拔毛）显著上调血清尿素和尿酸水平,但剪毛对这两个指标没有影响.长毛兔在采毛后48 h内,多数血清指标可恢复到采毛前水平,或呈恢复趋势;该研究筛选获得采毛应激指标血清总蛋白和肌酐,拔毛应激指标尿素和尿酸,同时发现肌酐、白蛋白和胆红素受地塞米松的显著影响.该研究结果可为初步揭示不同采毛方式应激生化机制提供参考.     

规模化屠宰场官方兽医及协检员的设置与职责

@@进入新世纪以来,伴随SARS、禽流感和猪链球菌病等疫情在全球范围内的传播,对世界各国人民的身体健康构成极大威胁。因此,国家逐步加大对动物疫病的防控,相继颁布了《中华人民共和国动物防疫法》《动物检疫管理办法》等法律法规,使我国动物防疫和检疫工作走上了有法可依、有章可循的规范化、法制化轨道。屠宰检疫是动物检疫工作的重要组成部分,是保证人民群众食肉安全的重要手段。猪肉及猪产品是广大群众餐桌上不可或缺的食品,国家为保证生猪产品质量安全,保障人民身体健康对生猪屠宰实行定点屠宰、集中检疫,从而使重大疫病的发生和流行得到有效控制。     

Seroprevalence of chlamydial infection in dairy cattle in Guangzhou, southern China

Chlamydia spp. are obligate intracellular gram-negative bacteria that cause a wide range of significant diseases in humans and animals worldwide, resulting in significant economic losses. Chlamydial infection in cattle has been reported in many countries including China. However, there has been no survey of chlamydial infection of dairy cattle in Guangzhou, southern China. The objective of the present investigation was to examine the chlamydial seroprevalence in dairy cattle in Guangzhou, subtropical southern China by using an indirect hemagglutination assay (IHA). The overall seroprevalence of chlamydial infection in dairy cattle was 7.25% (29/400). Greater than or equal to eight-yr-old dairy cattle had the highest seroprevalence (10.34%), followed by those that were ≥ 6 years old or < 7 years old dairy cattle (10.20%), although there were no statistically significant differences among different groups (P > 0.05). Dairy cattle with 5 pregnancies had the highest seroprevalence (10.81%). These results indicate that chlamydial infection was present in dairy cattle in Guangzhou, subtropical southern China, and integrated strategies and measures should be executed to control and prevent chlamydial infection and disease outbreak in the study region.     

鸭病毒性肝炎的诊断与防治

鸭病毒性肝炎是由鸭甲型肝炎病毒引起的一种急性、烈性、高度接触性传染病,由于病毒血清型较多,且易发生变异而难以有效地免疫预防,导致该病一直成为危害养鸭业健康发展的重要疾病。本文就引起鸭病毒性肝炎的病原、流行病学、临床症状、病理特征以及防治措施等方面进行综述,以期为临床鸭病毒性肝炎的诊断与防控提供参考。     

苜蓿皂甙对蛋鸡生产性能、屠体指标、胆固醇及血清脂质的影响

试验选用288只400日龄海兰褐商品蛋鸡,随机分为4个处理,每组72只鸡,设4个重复,每个重复18只鸡,采用单因素方差设计。在玉米-豆粕型日粮基础上添加0、30、60、90mg/kg的苜蓿皂甙进行60d的饲养试验,研究苜蓿皂甙对蛋鸡生产性能、屠体指标、胆固醇及血清脂质的影响。结果表明:日粮中添加苜蓿皂甙对产蛋率、平均蛋重、耗料量和料蛋比没有显著影响(P>0.05);60mg/kg和90mg/kg苜蓿皂甙能够显著降低腹脂率(P<0.05),60mg/kg能够提高半胫膛率(P<0.05)和降低肝脏胆固醇浓度(P<0.05)。添加组血清中总胆固醇极显著降低(P<0.01),60mg/kg和90mg/kg苜蓿皂甙组甘油三酯和低密度脂蛋白质显著降低(P<0.05),高密度脂蛋白有所提高(P>0.05)。综合分析得出,日粮中添加60mg/kg的苜蓿皂甙效果最佳。