Mycobacterium Avium Paratuberculosis: A Disease Burden on the Dairy Industry

Abstract

Mycobacterium avium paratuberculosis is responsible for paratuberculosis or Johne’s disease in cows, having economic impacts on the dairy industry and a prevalence rate exceeding 50% in dairy herds. The economic burden of Johne’s disease relates to decreased milk production and costs of disease prevention, treatment, and management, while having an economic impact on dairy producers, processors, consumers, and stakeholders of the dairy industry. Determining the true economic impact of the disease is difficult at regional and farm level as symptoms are not evident in subclinically infected animals. At present, the virulence, pathogenicity, persistence, and infectious dose of M. avium paratuberculosis are poorly understood, consequently effective paratuberculosis control measures remain obscure. M. avium paratuberculosis is potentially zoonotic with foodborne transmission a public health risk due to a possible causative link with inflammatory bowel disease in humans. A preventive approach is necessary to reduce the presence of this drug-resistant pathogen in dairy herds and subsequently dairy food. The use of inefficient diagnostic tests coupled with the long latency period of infection results in delayed animal culling and trade of asymptomatic animals, leading to regional transmission and increased disease prevalence. To date, there has been limited success at controlling and treating this terminal endemic disease, leading to significant prevalence rates. This study aims to outline the key factors associated with Johne’s’ disease while outlining its significant impact on the dairy sector.

MAP, Johne’s disease and the microbiome; current knowledge and future considerations

“…These categories are based on the presence and severity of clinical signs, the rate of environmental shedding and the likelihood of detection with current MAP diagnostic methods [ 4 ]. Animals that are infected with MAP, but have no evidence of disease and cannot be detected with current diagnostic methods, are said to be in the silent stage [ 5 ]. Subclinical animals show an immune response, shedding low but infectious levels of the pathogen.…”

“…As there are no effective cures yet developed for JD, these control programmes are employed in order to try and eradicate the disease. Furthermore, the current vaccines for MAP compromises the diagnosis of bovine tuberculosis in cattle [ 5 , 51 ]. JD vaccination programmes have been implemented in several countries including the USA, which previously used the commercially available vaccine Mycopar®, but have now been discontinued (2019).…”

Goat Paratuberculosis: Experimental Model for the Evaluation of Mycobacterium Persistence in Raw Milk Cheese

“…Paratuberculosis (PTB), also known as Johne's disease, is a contagious bacterial disease typical of domestic and wild ruminants, characterized by chronic progressive granulomatous enteritis [1], with consequent severe deterioration of the general conditions of animals and economic losses [2]. Although the disease was first reported in cattle, the infection has also been identified worldwide among small ruminants [3].…”

Electrochemical Detection of Serum Antibodies Against Mycobacterium avium Subspecies paratuberculosis

“…JD affects domestic animals such as farm deer, sheep, and dairy cattle. The prevalence of JD in cattle in Australia, New Zealand, Europe, and the United States was estimated to range from 10 to 60% (1)(2)(3)(4). United States Department of Agriculture (USDA) reported that 68.1% of dairy herds in the US are contaminated with MAP, and the most recent report estimated that the actual herd-level prevalence of MAP was higher than 90% (5).…”

“…Economic loss caused by JD in dairy herds is mostly due to the reduced milk production and premature culling of JD-affected cattle (7). In the USA, JD causes an estimated annual loss of $220 million to the agricultural economy (4,(8)(9)(10).…”