Prevalence of bovine immunodeficiency virus infection in cattle in Great Britain
Prevalence of bovine immunodeficiency virus infection in cattle in Great Britain
复制标题
英国牛中牛免疫缺陷病毒感染的患病率
DOI：
10.1136/vr.149.15.459
复制
发表时间：
2001
影响因子：
2.2
通讯作者：
S. Weightman
中科院分区：
文献类型：
--
作者：
L. Scobie;O. Jarrett;C. Venables;A. R. Sayers;S. Weightman
Correspondence to Mr Venables SEROEPIDEMIOLOGICAL evidence indicates that bovine immunodeficiency virus (BIV) infection has a worldwide distribution. Surveys have shown seropositive cattle in the USA (Amborski and others 1989, Cockerell and others 1992, St Cyr Coats and others 1994), Canada (McNab and others 1994), the Netherlands (Horzinek and others 1991), New Zealand (Horner 1991), France (Polack and others 1996), Japan (Hirai and others 1996), Italy (Cavirani and others 1998), Korea (Cho and others 1999), Australia (Burkala and others 1999), Pakistan (Meas and others 2000b) and Cambodia (Meas and others 2000a). Although the role of BIV in disease remains unclear, infection has been associated with lymphadenopathy, wasting and encephalitis (Snider and others 1996, Munro and others 1998). The virus is related to other lentiviruses (Garvey and others 1990), including human immunodeficiency virus and feline immunodeficiency virus, that disrupt the immune system. However, conclusive evidence that BIV causes immunodeficiency in cattle has yet to be established. This short communication reports a survey of cattle in the UK for evidence of antibodies to BIV. In addition to overall seroprevalence, comparative beef and dairy and herd incidences were calculated. Based on the distribution of bovine tuberculosis in the UK, and the perceived potential for BIV to compromise the immune system, a hypothesis that the incidence of BIV infection may be higher in the south-west areas of the UK, where tuberculosis is most prevalent in cattle (Krebs 1997), was also tested. As a representative sample of the national herd, a panel of sera from 971 adult cattle from 49 herds was drawn at random. Half of the cattle were from beef breeds and half were from dairy breeds. The median number of animals sampled from each herd was 20. The sera were tested for antibodies to the transmembrane protein of BIV using a highly specific enzyme immunoassay as described previously (Scobie and others 1999), with the following modifications. Microtitre plates coated with TMAI peptide (Scobie and others 1999) were blocked with 2 per cent dried milk powder (Marvel)/20 per cent goat serum. The serum samples were diluted 1:10 in wash buffer (WB) (phosphate-buffered saline, 0 1 per cent Tween-20) and 1 per cent dried milk powder. The secondary antibody used was mouse anti-bovine IgG conjugated with biotin, diluted in WB and 1 per cent dried milk powder. The signal was amplified using alkaline phosphatase-linked streptavidin diluted in WB. All incubations were carried out for one hour at room temperature. The chromogen used was p-nitrophenol phosphate and absorbance was read at 405 nm (A405). A sample:positive control (s:P) ratio was calculated for each serum sample, as follows:
