An international team of researchers, led by Ibrahim Elsohaby, tested 31 herds of animals with prior histories of Johne’s disease in the Eastern Province in Saudi Arabia. The Eastern Province is the third most populous province in Saudi Arabia, with varying climatic conditions from semi-desert to desert. The Eastern Province shares the borders with five countries (Iraq, Kuwait, Oman, Qatar, and the United Arab Emirates), which may increase the risk of pathogen introduction to the country.
A total of 649 sheep, goats, cattle, and camels were tested by ELISA on serum samples and IS900 PCR on fecal samples. The study was reported this month in the journal Animals. The pie charts below were created to summarize the study findings. They reveal high infection rates among all four animals species and the higher diagnostic sensitivity of fecal PCR as compared to serum ELISAs. Interestingly, the S (sheep)-strain of MAP was more prevalent than the C (cattle)-strain.
Abstract
The objectives of the present study were to characterize Mycobacterium avium subsp. paratuberculosis (MAP) infection using serological and molecular tools and investigate the distribution and molecular characterization of MAP strains (cattle (C) and sheep (S) types) in sheep, goat, cattle, and camel herds in Eastern Province, Saudi Arabia. Serum and fecal samples were collected from all animals aged >2 years old in 31 herds (sheep = 8, goats = 6, cattle = 8 and camels = 9) from January to December 2019. Serum samples were tested by ELISA for the detection of MAP antibodies. Fecal samples were tested by PCR for the detection of MAP IS900 gene and the identification of MAP strains. MAP antibodies were detected in 19 (61.3%) herds. At the animal level, antibodies against MAP were detected in 43 (19.5%) sheep, 21 (17.1%) goats, 13 (19.7%) cattle and 22 (9.1%) camels. The IS900 gene of MAP was detected in 23 (74.2%) herds and was directly amplified from fecal samples of 59 (26.8%) sheep, 34 (27.6%) goats, 20 (30.3%) cattle and 36 (15.0%) camels. The S-type was the most prevalent MAP type identified in 15 herds, and all were identified as type-I, while the C-type was identified in only 8 herds. The IS900 sequences revealed genetic differences among the MAP isolates recovered from sheep, goats, cattle and camels. Results from the present study show that MAP was prevalent and confirm the distribution of different MAP strains in sheep, goat, cattle and camel herds in Eastern Province, Saudi Arabia.
This graphic from the publication shows an example of Johne’s disease in goats.
Comment
Few reports on paratuberculosis in Saudi Arabia are available making this an important addition to the body of evidence that Johne’s disease is a global problem.