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United States Department of Agriculture

Agricultural Research Service

Title: USDA Ag Research Service Investigators Are Studying New Diagnostic Tests, How the Organism Works, What Causes Infection, and How to Slow Johne's Spread

Author
item Stabel, Judith

Submitted to: Hoard's Dairyman
Publication Type: Proceedings
Publication Acceptance Date: July 1, 2005
Publication Date: January 10, 2006
Citation: Stabel, J.R. 2006. USDA Ag Research Service Investigators are studying new diagnostic tests, how the organism works, what causes infection, and how to slow Johne's spread. Proceedings of Hoard's Dairyman. p. 7.

Interpretive Summary: Johne's disease is a chronic, debilitating intestinal disorder in cattle characterized by diarrhea, reduced feed intake, weight loss and death. Cattle usually become infected as young calves by ingesting feces containing the causative bacteria. However, symptoms of disease do not usually present themselves until the animals reach 3 to 5 years of age or even older. During this time the animal is infected and may be shedding the organism in its feces without showing any clinical signs of disease. In addition to reduced milk production by these animals, they also present a potential infective threat to the rest of the herd. Johne’s disease is difficult to diagnose and therefore to control. Development of accurate and sensitive diagnostic tests is dependent upon understanding the immune responses of the host animal during infection. This paper describes work that is currently being conducted on paratuberculosis by scientists within ARS. It is a multi-factorial approach to research with focus on understanding the immunology and pathogenesis of the disease in order to develop new tools for the detection of infection. It is also possible that this information will lead to new preventative and therapeutic regimes.

Technical Abstract: Johne's disease is a chronic, debilitating intestinal disorder in cattle characterized by diarrhea, reduced feed intake, weight loss and death. Cattle usually become infected as young calves by ingesting feces containing the causative bacteria. However, symptoms of disease do not usually present themselves until the animals reach 3 to 5 years of age or even older. During this time the animal is infected and may be shedding the organism in its feces without showing any clinical signs of disease. In addition to reduced milk production by these animals, they also present a potential infective threat to the rest of the herd. Johne’s disease is difficult to diagnose and therefore to control. Development of accurate and sensitive diagnostic tests is dependent upon understanding the immune responses of the host animal during infection. This paper describes work that is currently being conducted on paratuberculosis by scientists within ARS. It is a multi-factorial approach to research with focus on understanding the immunology and pathogenesis of the disease in order to develop new tools for the detection of infection. It is also possible that this information will lead to new preventative and therapeutic regimes.

Last Modified: 7/22/2014