Description    MYCOBACTERIUM AVIUM subspecies PARATUBERCULOSIS causes infectious chronic granulomatous enteritis in ruminants. Calves are most susceptible to infection from birth to a few months of age but the incubation period prior to the onset of clinical signs generally ranges from 2 to 10 years. Fecal-oral transmission from cows to calves is believed to be the most common method of spread; also shed in milk and colostrum. Intrauterine infection can occur but does not appear to be of major importance in the transmission of paratuberculosis. Affected cattle continue to eat even as chronic diarrhea and weight loss persist. In goats the disease primarily affects the upper GI tract and weight loss might be the only obvious sign, with diarrhea intermittent or absent. Usually affects goats 2-years-old or older but yearlings can be affected. Paratuberculosis is common in flocks of sheep but identification of individual sheep with subclinical infections is difficult. Sheep might not show signs for years after being infected and there is often weight loss without other signs.
Species   Bovine, Caprine, Ovine
Signs   Agalactia, Alopecia, Anestrus, Anorexia, Dark color stools, feces, Dehydration, Diarrhea, Dryness of skin or hair, Dullness, Female infertility, Fever, Generalized weakness, Head, face, ears, jaw, nose, nasal, swelling, Inability to stand, Lack of growth or weight gain, Pale, Polydipsia, Polyphagia, Rough hair coat, Skin edema, Tachycardia, Underweight, poor condition, thin, emaciated, unthriftiness, ill thrift, Weight loss
References   Lavers CJ et al. Sensitivity and specificity of repeated test results from a commercial milk enzyme-linked immunosorbent assay for detection of Mycobacterium avium subspecies paratuberculosis in dairy cattle. Journal of the American Veterinary Medical Association 2015;246:236-244 [Web Reference]
Laurin EL et al. The association of detection method, season, and lactation stage on identification of fecal shedding in Mycobacterium avium ssp. paratuberculosis infectious dairy cows. Journal of Dairy Science 2015;98:211-220 [Web Reference]
De Buck J et al. Metabolomic Profiling in Cattle Experimentally Infected with Mycobacterium avium subsp. paratuberculosis. PLoS ONE 2014;9:e111872 [Web Reference]
Mercier P et al. Vaccination of kids under one month of age with a killed vaccine and reduction in the frequency of faecal shedding of Mycobacterium avium subspecies paratuberculosis. Small Ruminant Research 2014;121:425-433 [Web Reference]
Stabel JR et al. Clinical disease and stage of lactation influence shedding of Mycobacterium avium subspecies paratuberculosis into milk and colostrum of naturally infected dairy cows. Journal of Dairy Science 2014;97:6296-6304 [Web Reference]
Windsor P et al. Effectiveness of Gudair vaccine for the control of ovine Johne`s disease in flocks vaccinating for at least 5 years. Australian Veterinary Journal 2014;92:263-268 [Web Reference]
Kralik P et al. Evidence of passive faecal shedding of Mycobacterium avium subsp. paratuberculosis in a Limousin cattle herd. The Veterinary Journal 2014;201:91-94 [Web Reference]
Zare Y et al. Heritability estimates for susceptibility to Mycobacterium avium subspecies paratuberculosis infection defined by ELISA and fecal culture test results in Jersey cattle. Journal of Dairy Science 2014;97:4562-4567 [Web Reference]
Arsenault RJ et al. From mouth to macrophage: mechanisms of innate immune subversion by Mycobacterium avium subsp. paratuberculosis. Veterinary Research 2014;45:54 [Web Reference]
Brito BP et al. Association between caudal fold tuberculin test responses and results of an ELISA for Mycobacterium avium subsp paratuberculosis and mycobacterial culture of feces in tuberculosis-free dairy herds. Journal of the American Veterinary Medical Association 2014;244:582-587 [Web Reference]
Donat K et al. Prevalence and control measures within the herd influence the performance of ELISA tests. Veterinary Record 2014;174:119 [Web Reference]
Angelidou E et al. Bayesian validation of a serum and milk ELISA for antibodies against Mycobacterium avium subspecies paratuberculosis in Greek dairy goats across lactation. Journal of Dairy Science 2014;97:819-828 [Web Reference]
Lavers CJ et al. Evaluation of milk ELISA fordetection of Mycobacterium avium subspecies paratuberculosis indairy herds and association with within-herd prevalence. Journal of Dairy Science 2014;97:299-309 [Web Reference]
Copyright © 2015 Cornell University College of Veterinary Medicine