A critical review on diagnosis of paratuberculosis in domestic animals

Paratuberculosis, caused by Mycobacterium avium subspecies paratuberculosis, is a bacterial disease of domestic and wild ruminants.It progresses very slowly and, hence, takes several years to develop clinical signs.The importance of the disease is ignored because of its slow progression and subtle influence on production.The prevalence of the disease in different parts of the world has been confirmed; it is high enough to control and minimize losses.A number of tests are used to diagnose, but no one seems too ideal since most diagnostics are unable to diagnose infected animals before the animal contaminates the environment.New advanced techniques no doubt increase diagnostic efficiency with reduced time, but they fail to diagnose the disease before shedding bacilli.Most of the diagnostics explore the body response against the pathogen for its detection.These strategies should not be applied in paratuberculosis diagnosis.Host response against bacilli is so late that the detection of infection based on it is of no use as animals contaminate the environment by that time.The present review summarizes the available diagnostic techniques in domestic animals.