Yersinia pseudotuberculosis infection in a suckler calf in the United Kingdom: a case report

Enterocolitis caused by Yersinia pseudotuberculosis was identified by bacterial culture and histopathology in a 5-month old suckler calf. No other significant enteric pathogens were detected. Diagnosis of this condition can be missed if selective media are not used for bacteriology and if histopathology is not attempted or the alimentary tract is unsuitable for examination. This is the first case report of Y. pseudotuberculosis infection in a calf in the United Kingdom.     

Investigation of serology for diagnosis of outbreaks of botulism in cattle

Serology has been used to diagnose retrospectively types C and D outbreaks of botulism in cattle in Australia and this study has investigated whether the approach would be applicable in England and Wales. Three hundred sera from routine surveillance submissions in England and Wales were used as a negative control population. Some stored sera were available from a small number of clinical cases of botulism and 125 samples were collected from cohort groups of clinical cases in four new outbreaks of botulism. Three of these outbreaks were identified as being caused by type D Clostridium botulinum toxin. Sera were tested by antibody ELISA in laboratories in Australia and Germany. There was no increase in the proportion of animals seropositive to type C or D antibody in the botulism-associated cattle. The proportion of samples which were seropositive to type D antibodies was <2% in both the negative control and outbreak populations. It was concluded that single time serology is unlikely to be helpful for retrospective diagnosis of outbreaks of type D botulism in England and Wales.     

Serological investigation of aborted sheep and pigs for infection by Neospora caninum

Serology for Neospora caninum was undertaken using direct ELISAs on sera from 660 aborted sheep and 454 breeding sows, which had aborted or were considered infertile. All ovine sera were further tested by indirect fluorescent antibody test (IFAT) for N. caninum, and a latex agglutination test (LAT) for Toxoplasma gondii was performed on 423 of the samples, including all those positive by ELISA. ELISA-positive porcine sera were tested by IFAT and an inhibition ELISA for antibodies to N. caninum and by LAT for T. gondii. Only 3 (0.45%) of the ovine sera were seropositive for N. caninum by both ELISA and IFAT whereas although 40 porcine sera were seropositive by ELISA all were negative by IFAT. The results suggest that environmental exposure to N. caninum occurs rarely in sheep and pigs.     

鸡绦虫病的诊断及其防治策略

随着我国养鸡业的迅速发展,集约化笼养已成为主要生产模式,由于采取笼养,客观上切断了寄生虫的传播途径,使鸡的线虫病、吸虫病、绦虫病的发病率大大减少,也导致某些大型养鸡场（户）放松了警惕。尤其对于鸡绦虫病,若不注意防范,同样会给鸡场带来巨大经济损失。所谓鸡绦虫病主要是由于鸡吞食了含绦虫幼虫的中间宿主（蚂蚁、甲虫、苍蝇、蚯蚓、陆地螺蛳等）而感染的蠕虫病。     

舟形嗜气管吸虫在黑龙江省鸭体内检出

2003年4月，在黑龙江省大庆市某养殖场送检鸭的气管内检出3条腹面扁平、背面隆起的像半粒黄豆样但稍薄的虫体，由于1条虫体在采集过程中已被剪断，剩余2条虫体经盐酸卡红染色，显微镜下观察和测量，鉴定为舟形嗜气管吸虫。这是黑龙江省首次检出此虫体。     

欣虫净复方注射剂对羊体内寄生虫驱除试验

伊维菌素和吡喹酮是目前优良的抗动物寄生虫病药物,伊维菌素是近20年来同时防治动物各种线虫病、体外寄生虫病效果最好的药物之一,而吡喹酮在防治动物的绦虫病(包括绦虫蚴病),吸虫病(尤其是血吸虫)方面具有其他抗寄生虫药物无法比拟的优点,这两种药物如果组成复方制剂在驱虫谱上可以对几乎所有的动物寄生虫产生驱杀作用,但由于吡喹酮在多种溶媒中的溶解度较低,导致注射剂量过大,容易引起注射部位吸收缓慢,炎症不易消除.本试验应用自制的以高浓度吡喹酮(20%)与适量伊维菌素组合的复方注射剂"欣虫净",通过临床试验观察了该制剂的驱虫效果.     

绵羊痒螨病的免疫学研究进展

羊痒螨成虫的盐水和吐温萃取物对已经发展到活跃期的痒螨病绵羊有显著的保护效应,通过PCR扩增获得了羊痒螨的cDNA编码免疫原Pso01,试验证实绵羊痒螨保护性抗原的成分复杂。在该病诊断方面,应用改进的ELISA法诊断自然感染的羊痒螨病,其敏感性为93．7％,免疫组织化学研究表明,在感染后4d受损伤的皮肤中CD4^＋和CD45RA^＋细胞的数量显著增加,并且γδT细胞和树突状细胞的CD1b^＋显著增加持续了8d。随着绵羊瘁螨cRNA表达文库的建立,为应用现代分子生物学技术开发抗绵羊瘁螨病的疫苗积累了有价值的资料,从而为应用免疫学方法防控绵羊瘁螨病展示了光明的前景。