- C.G. Mackintosh (1)
- J.O. Mecham (1)
- P. Nol (1)
- R. O'Brien (1)
- I. Pavlik (1)
- L.M. Reister (1)
- P.A. Rijn van (1)
- K.C. Vercauteren (1)
- W.C. Wilson (1)
Experimental infection of white-tailed deer with bluetongue virus serotype 8
Drolet, B.S. ; Reister, L.M. ; Mecham, J.O. ; Wilson, W.C. ; Nol, P. ; Vercauteren, K.C. ; Rijn, P.A. van; Bowen, R.A. - \ 2013
Veterinary Microbiology 166 (2013)3-4. - ISSN 0378-1135 - p. 347 - 355.
epizootic-hemorrhagic-disease - polymerase chain-reaction - wild ruminants - red deer - antilocapra-americana - pronghorn antelope - cervus-elaphus - climate-change - epidemiology - spain
Bluetongue (BT) is an insect-transmitted, economically important disease of domestic and wild ruminants. Although only five of the 26 reported bluetongue virus (BTV) serotypes are considered endemic to the USA, 10 exotic serotypes have been isolated primarily in the southeastern region of the country since 1999. For an exotic BTV serotype to become endemic there must be susceptible animal species and competent vectors. In the USA, sheep and white-tailed deer (WTD) are the primary sentinel livestock and wildlife species, respectively. In 2006, BTV-8 was introduced into Northern Europe and subsequently overwintered, causing unprecedented livestock disease and mortality during the 2006-2007 vector seasons. To assess the risk of the European strain of BTV-8 to North American WTD, and understand the role they could play after a similar introduction, eight bluetongue-seronegative WTD were inoculated with BTV-8. Body temperatures and clinical signs were recorded daily. Blood samples were analyzed for BTV RNA with quantitative real time reverse transcriptase polymerase chain reaction (qRT-PCR), serum analyzed for BTV antibodies by cELISA, and tissues taken for histopathology and qRT-PCR. All eight deer became infected and developed moderate to severe clinical disease from days 8 to 15. Peak viremia was from day 7 to 10 with detectable titers through the end of the study (28 days) in most deer. Serum antibody was detected by day 6, peaked by day 10 and continued through day 28. We conclude that North American WTD are highly susceptible to BTV-8 and would act as clinical disease sentinels and amplifying hosts during an outbreak.
Immunological and molecular characterization of susceptibility in relationship to bacterial strain differences in Mycobacterium avium subsp paratuberculosis infection in the red deer (Cervus elaphus)
O'Brien, R. ; Mackintosh, C.G. ; Bakker, D. ; Kopecna, M. ; Pavlik, I. ; Griffin, J.F.T. - \ 2006
Infection and Immunity 74 (2006)6. - ISSN 0019-9567 - p. 3530 - 3537.
fragment-length-polymorphism - johnes-disease - protective efficacy - immune-responses - new-zealand - wild ruminants - farmed deer - tuberculosis - sheep - is900
Johne's disease (JD) infection, caused by Mycobacterium avium subsp. paratuberculosis, represents a major disease problem in farmed ruminants. Although JD has been well characterized in cattle and sheep, little is known of the infection dynamics or immunological response in deer. In this study, typing of M. avium subsp. paratuberculosis isolates from intestinal lymphatic tissues from 74 JD-infected animals showed that clinical isolates of M. avium subsp. paratuberculosis from New Zealand farmed red deer were exclusively of the bovine strain genotype. The susceptibility of deer to M. avium subsp. paratuberculosis was further investigated by experimental oral-route infection studies using defined isolates of virulent bovine and ovine M. avium subsp. paratuberculosis strains. Oral inoculation with high (109 CFU/animal) or medium (107 CFU/animal) doses of the bovine strain of M. avium subsp. paratuberculosis established 100% infection rates, compared to 69% infection following inoculation with a medium dose of the ovine strain. The high susceptibility of deer to the bovine strain of M. avium subsp. paratuberculosis was confirmed by a 50% infection rate following experimental inoculation with a low dose of bacteria (103 CFU/animal). This study is the first to report experimental M. avium subsp. paratuberculosis infection in red deer, and it outlines the strong infectivity of bovine-strain M. avium subsp. paratuberculosis isolates for cervines.