Mycobacterium paratuberculosis cultured from milk and supramammary lymph nodes of infected asymptomatic cows

• Published in: Journal of Clinical Microbiology Vol. 30; no. 1; pp. 166 - 171
• Main Authors: Sweeney, R.W. (University of Pennsylvania School of Veterinary Medicine, Kennett Square, PA), Whitlock, R.H, Rosenberger, A.E
• Format: Journal Article
• Language: English
• Published: United States American Society for Microbiology 01-01-1992
• Subjects: Animals; Cattle; Cattle Diseases - microbiology; Female; GLANDE MAMMAIRE; GLANDULAS MAMARIAS; INFECCION; INFECTION; LAIT; LECHE; Lymph Nodes - microbiology; Mammary Glands, Animal; Milk - microbiology; Mycobacterium avium subsp. paratuberculosis - growth & development; Mycobacterium avium subsp. paratuberculosis - isolation & purification; MYCOBACTERIUM PARATUBERCULOSIS; Paratuberculosis - microbiology; SINTOMAS; SISTEMA LINFATICO; SYMPTOME; SYSTEME LYMPHATIQUE; VACAS LECHERAS; VACHE LAITIERE
• ISSN: 0095-1137; 1098-660X
• DOI: 10.1128/jcm.30.1.166-171.1992

Milk and supramammary lymph node samples were obtained from asymptomatic cows infected with Mycobacterium paratuberculosis at the time of slaughter. Of 81 supramammary lymph node samples, 22 (27%) were culture positive for M. paratuberculosis. Of 77 milk samples, 9 (11.6%) were culture positive. The prevalence of supramammary lymph node or milk infection was highest with heavy fecal shedding of M. paratuberculosis and lowest with light shedding. The serologic status of the cow was not useful for predicting the risk of supramammary lymph node or milk infection. Shedding of M. paratuberculosis occurs in the milk of asymptomatic infected cows but, apparently, less frequently than previously reported for symptomatic cows