Using Omics Approaches in the Discovery of Biomarkers for Early Diagnosis of Johne’s Disease in Sheep and Goats

Abstract

Johne’s disease (JD) is caused by Mycobacterium avium subsp. paratuberculosis (MAP) and is an important and emerging problem in livestock; therefore, its control and prevention is a priority to reduce economic losses and health risks. Most JD research has been carried out on cattle, but interest in the pathogenesis and diagnosis of this disease in sheep and goats is greatest in developing countries. Sheep and goats are also a relevant part of livestock production in Europe and Australia, and these species provide an excellent resource to study and better understand the mechanism of survival of MAP and gain insights into possible approaches to control this disease. This review gives an overview of the literature on paratuberculosis in sheep and goats, highlighting the immunological aspects and the potential for “omics” approaches to identify effective biomarkers for the early detection of infection. As JD has a long incubation period before the disease becomes evident, early diagnosis is important to control the spread of the disease.

Mycobacterium avium Subspecies paratuberculosis Infection and Immunopathological Changes in Animals: A Review

“…Changes in TLR gene expression in sheep at the time of experimental infection with MAP have been observed in both in vitro and in vivo experiments (Plain et al, 2010). TLR2 regulates the specific immune system in the initial phases of JD and influences development of disease in selected tissues and in sheep PBMCs (Fiorentina et al, 2021). TLR2 mRNA expression rises in the multibacillary form of JD, owing to a stronger inflammatory response in regions at which the majority of microbes are located (Nalubamba et al, 2008).…”

Genome‐wide association study for antibody response to Mycobacterium avium ssp. paratubeculosis in goats

“…A genome‐wide association study (GWAS) in Garfagnina goats identified several regions associated with serological response to MAP (Cecchi et al, 2017). In addition to the GWAS, RNAseq and MicroRNA sequencing studies in cattle have identified expression patterns associated with JD progression and have suggested their potential as diagnostic tools (Casey et al, 2015; Fiorentina et al, 2021; Malvisi et al, 2016, 2020; Marino et al, 2017). The extension of these studies to goats is of interest considering the differences in progression of the disease among species.…”

Identification of Mycobacterium avium subspecies paratuberculosis in sheep farms in Bayannaoer, Inner Mongolia, China (short communication)

“…An economic study showed that MAP infection reduced the profit efficiency from 84% to 64% in Italian dairy sheep and goat farms [ 8 ]. Other countries and regions have also shown varying degrees of economic losses as a result of PTB [ 9 ].…”