A long-term study in Merino sheep experimentally infected with subsp. : clinical disease, faecal culture and immunological studies

Stewart, D. F.; Vaughan, J.A.; Stiles, Paula L; Noske, P; Tizard, Mark; Prowse, Stephen J.; Michalski, Wojtek P.; Butler, K. L.; Jones, Stephen L.

doi:10.1016/j.vetmic.2004.09.007

Cited by 47 publications

(73 citation statements)

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“…Until 2000, the majority of experimental studies in sheep did not use characterized ovine MAP strains, in contrast to later studies which have used tissue homogenates or low passage ovine MAP strains grown in vitro (Gwozdz et al, 2000a,b;Stewart et al, 2004;. The most common MAP isolates from clinical JD in sheep belong to the ovine genotype (Motiwala et al, 2004;Sevilla et al, 2005;Sevilla et al, 2007).…”

Section: Long-term Ovine Map Challenge Modelmentioning

confidence: 99%

Experimental challenge models for Johne's disease: A review and proposed international guidelines

Hines

Stabel

Sweeney

et al. 2007

Veterinary Microbiology

125

140

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An international committee of Johne's disease (JD) researchers was convened to develop guidelines for JD challenge studies in multiple animal species. The intent was to develop and propose international standard guidelines for models based on animal species that would gain acceptance worldwide. Parameters essential for the development of long-term and short-term infection models were outlined and harmonized to provide a ''best fit'' JD challenge model for cattle, goats, sheep, cervids, and mice. These models will be useful to study host-pathogen interactions, host immunity at the local and systemic level, and for evaluating vaccine candidates and therapeutics. The consensus guidelines herein list by animal species strains of Mycobacterium avium subsp. paratuberculosis used, challenge dose, dose frequency, age of challenge, route of challenge, preparation of inoculum, experimental animal selection, quality control, minimal experimental endpoints and other parameters. #

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Section: Long-term Ovine Map Challenge Modelmentioning

confidence: 99%

Experimental challenge models for Johne's disease: A review and proposed international guidelines

Hines

Stabel

Sweeney

et al. 2007

Veterinary Microbiology

125

140

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“…Gamma interferon ELISAs have also been approved or are under consideration for approval for use in primates, humans, and cervids. Although IFN-c ELISAs have been evaluated for diagnosis of paratuberculosis in cattle, [9][10][11] sheep, 20,21,26 and goats, 16,27 formal analysis of sensitivity and specificity in naturally infected sheep has not been done.…”

Section: Introductionmentioning

confidence: 99%

Evaluation of the Gamma Interferon ELISA in Sheep Subclinically Infected withMycobacterium AviumSubspeciesParatuberculosisUsing a Whole-Cell Sonicate or a Johnin Purified-Protein Derivative

2006

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Abstract. The aim of the study reported here was to estimate the sensitivity and specificity of the gamma interferon (IFN-c) ELISA for paratuberculosis in sheep using receiver-operating characteristic analysis. Bacteriologic culture of tissues was used to define the reference positive population (n 5 33). Two reference negative populations were used: culture-negative sheep from infected flocks (n 5 77), and sheep from noninfected flocks (n 5 358). We also evaluated the accuracy of 2 Mycobacterium avium subspecies paratuberculosis (MAP) antigen preparations, a whole-cell sonicate (MpS) and a johnin purified-protein derivative (PPDj). The source of the reference negative sheep used in the analysis affected overall accuracy of the IFN-c ELISA. The area under the curve was 0.683 (95% confidence interval 0.574-0.787), using culturenegative sheep from infected flocks, was 0.831 (0.764-0.889), using sheep from noninfected flocks for the MpS, and was 0.809 (0.726-0.881) and 0.897 (0.862-0.925) for the PPDj, respectively. Using the MpS, the cut point that classified the most sheep correctly was an optical density reading of 0.20, for sensitivity of 40.7% (19.4-57.6) and specificity of 88.7% (77.0-95.7) or 97.6% (93.04-99.5), depending on the reference negative population used. Using the PPDj, the cut point that classified the most sheep correctly was 0.25 for sensitivity of 66.7% (47.2-82.7) and specificity of 93.5% (85.5-97.9) or 98.3% (96.4-99.4), respectively. The PPDj was more accurate at identifying MAP-infected sheep than was the MpS (P 5 0.034).

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“…Domestic sheep and cattle are most commonly infected with their named strain type respectively, suggesting that there may be a certain degree of host specificity (Whittington et al, 2000). However, neither strain is entirely specific for a single ruminant species, but both are infective for a variety of hosts, both naturally and experimentally (Ris et al, 1987;Pavlík et al, 1995;Stewart et al, 2004). Type I strains have rarely been isolated from wildlife species (Stevenson, 2010).…”

Section: Discussionmentioning

confidence: 99%

Occurrence, Diagnosis, and Strain Typing of Mycobacterium Avium Subspecies Paratuberculosis Infection in Rocky Mountain Bighorn Sheep (Ovis Canadensis Canadensis) in Southwestern Alberta

Forde

Kutz

Buck

et al. 2012

Journal of Wildlife Diseases

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ABSTRACT:The role that wildlife may play in the transmission of Mycobacterium avium subspecies paratuberculosis (Map), the causative agent of Johne's disease (JD), and the potential consequences of infection in these populations are being given increasing consideration. A yearling male Rocky Mountain bighorn sheep (Ovis canadensis canadensis) from southwestern Alberta, Canada, was found infected with Map in August 2009. Clinical signs of emaciation and diarrhea and histologic findings of diffuse granulomatous enteritis of the distal ileum, lymphadenitis of the mesenteric lymph nodes, and lymphangitis of the ileum were similar to previously described cases of JD in bighorn sheep. Infection with Map was confirmed by bacterial isolation through fecal culture, acid-fast staining, and polymerase chain reaction (PCR) of IS900. The Map1506 gene was sequenced, and the isolate was identified as a Cattle (Type II) strain. In a follow-up herd-level survey, three of 44 fecal samples (7%) from individual bighorn sheep from the same herd as the index case were PCRpositive and identified as Type II Map strains. Twenty-five samples from a distant bighorn population were negative. Additional strain typing of the isolates from the index case and the positive fecal samples was done by sequencing three discriminatory short sequence repeat (SSR) regions. All four SSR profiles differed from one another, suggesting multiple introductions or a long-existing circulation of Map within this bighorn population. Detailed molecular analyses are essential for understanding and managing diseases at the wildlife-livestock interface.

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A long-term study in Merino sheep experimentally infected with subsp. : clinical disease, faecal culture and immunological studies

Cited by 47 publications

References 0 publications

Experimental challenge models for Johne's disease: A review and proposed international guidelines

Experimental challenge models for Johne's disease: A review and proposed international guidelines

Evaluation of the Gamma Interferon ELISA in Sheep Subclinically Infected withMycobacterium AviumSubspeciesParatuberculosisUsing a Whole-Cell Sonicate or a Johnin Purified-Protein Derivative

Occurrence, Diagnosis, and Strain Typing of Mycobacterium Avium Subspecies Paratuberculosis Infection in Rocky Mountain Bighorn Sheep (Ovis Canadensis Canadensis) in Southwestern Alberta

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