Pathological, microscopic, and molecular diagnosis of paratuberculosis/John’s disease in naturally infected dromedary camel (Camelus dromedarius)

Vet World Vol.16 June-2023 Article-13

Research Article

Veterinary World, 16(6): 1277-1283

https://doi.org/10.14202/vetworld.2023.1277-1283

El Tigani Ahmed El Tigani-Asil¹, Ghada El Derdiri Abdelwahab¹, El Hadi Ahmed Mohamed Abdu², Abdelnasir Mohammed Adam Terab¹, Nasareldien Altaib Hussein Khalil¹, Zhaya Jaber Mohammed Al Marri¹, Mohd Farouk Yuosf¹, Asma Abdi Mohamed Shah¹, Abdelmalik Ibrahim Khalafalla¹, and Hassan Zackaria Ali Ishag¹

1. Biosecurity Affairs Division, Development and Innovation Sector, Abu Dhabi Agriculture and Food Safety Authority, Abu Dhabi, United Arab Emirates.
2. Extension Services and Animal Health Division, Animal Wealth Sector, Abu Dhabi Agriculture and Food Safety Authority, Abu Dhabi, United Arab Emirates.

Background and Aim: Paratuberculosis (PTB) or John’s disease is a chronic disease of ruminants impeding the reproduction and productivity of the livestock sector worldwide. Since there is a lack of pathological studies explaining the nature and development of the disease in camels, this study aimed to highlight the anatomopathological changes of PTB in camels, which may help in verifying and validating some diagnostic tests used to detect the etiology of the disease in camel tissues.

Materials and Methods: In August 2017, at Alselaa border’s Veterinary Clinic of Al Dhafra Region, Western Abu Dhabi, UAE, one imported culled she-camel of 2 years old was subjected to clinical, microscopic, and anatomopathological investigations along with real-time quantitative polymerase chain reaction (q-PCR) to confirm the infection and correlate between clinical signs and pathological lesions of the PTB in dromedary camels.

Results: Clinically, typical clinical signs compliant with the pathognomonic gross and histologic lesions of PTB were seen in naturally infected dromedary camel. As presumptive diagnosis microscopically, acid-fast coccobacillus bacterium clumps were demonstrated in direct fecal smears as well as in scraped mucosal and crushed mesenteric lymph node films, and in histopathological sections prepared from a necropsied animal and stained by Ziehl-Neelsen stain. Free and intracellular acid-fast clump phagosomes were further confirmed as Mycobacterium avium subsp. paratuberculosis by q-PCR.

Conclusion: Clinical signs and pathological lesions of paratuberculosis in a dromedary camel were found to be similar to those of the other susceptible hosts. Keywords: acid-fast bacteria, dromedary camel, Mycobacterium, paratuberculosis.

Keywords: acid-fast bacteria, dromedary camel, Mycobacterium, paratuberculosis.

How to cite this article: El Tigani-Asil EA, Abdelwahab GE, Abdu EAM, Terab AMA, Khalil NAH, Al Marri ZJM, Yuosf MF, Shah AAM, Khalafalla AI, and Ishag HZA (2023) Pathological, microscopic, and molecular diagnosis of paratuberculosis/John’s disease in naturally infected dromedary camel (

Received: 05-03-2023 Accepted: 15-05-2023 Published online: 08-06-2023

Corresponding author: Hassan Zackaria Ali Ishag E-mail: hassan.ishag@adafsa.gov.ae

DOI: 10.14202/vetworld.2023.1277-1283

Copyright: El Tigani-Asil, et al. This article is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.