Related Experiment Video
Updated: Sep 25, 2025
Quantitation of Rabies Virus in Various Bovine Brain Structures
Published on: May 22, 2021
First identification of Mycobacterium avium subsp. paratuberculosis in wild ruminants in a zoo in Mexico
A L Hernández-Reyes1, G Chávez-Gris1, E Maldonado-Castro1
1National Autonomous University of Mexico (UNAM), School of Veterinary Medicine and Zootechnics (FMVZ), Center for Teaching, Research and Extension of Animal Production in High Plateau (CEIEPAA), Tequisquiapan-Ezequiel Montes Highway Km 8.5, 76790 Tequisquiapan, Queretaro, Mexico.
Background And Aim:
Paratuberculosis (PTB) is an infectious disease that induces chronic enteritis in ruminants. It is caused by Mycobacterium avium subsp. paratuberculosis (MAP). In this study, we evaluated the presence of MAP using bacteriological, molecular, and anatomopathological studies, based on the clinical suspicion of PTB in a zoo, in an area housing 10 scimitar-horned oryx (Oryx dammah), five giraffes (Giraffa camelopardalis), and three blue wildebeests (Connochaetes taurinus).
Materials And Methods:
From November 2016 to June 2017, fecal samples were collected from individuals of the three species on four occasions, resulting in a total of 56 fecal samples. In addition, five small intestine samples were collected from the necropsies of three adult scimitar-horned oryx females and two oryx calves. MAP identification was performed through isolation in Herrold's medium with egg yolk, mycobactin, and sodium pyruvate, Ziehl-Neelsen staining, IS900 polymerase chain reaction (IS900 PCR), and anatomopathological examination of intestine samples.
Results:
Diffuse granulomatous enteritis with abundant acid-fast bacilli was found in two out of five intestine samples from adult scimitar-horned oryx females. MAP was isolated in 7/56 (12.5%) of the fecal samples from four scimitar-horned oryx, one giraffe, and two wildebeest samples. Two out of 5 (40%) samples obtained from scimitar-horned oryx tested positive. IS900 PCR yielded five positive samples (two fecal samples and three small intestine samples). MAP isolates were classified as Type C (Cattle) using type-specific PCR.
Conclusion:
These results demonstrated the presence of MAP in the area evaluated and indicated the importance of both sampling live animals and conducting postmortem examinations. The use of bacteriological and histopathological diagnostic techniques demonstrated in this study will provide insight into the health status and prevalence of paratuberculosis in wild ruminants under human care.
Insights
Paratuberculosis (PTB) was detected in zoo ruminants, with Mycobacterium avium subsp. paratuberculosis (MAP) found in fecal and intestinal samples. This highlights the need for integrated diagnostic approaches in captive wildlife to monitor PTB prevalence.
Area of Science:
- Veterinary Microbiology
- Wildlife Health
- Infectious Diseases
Background:
- Paratuberculosis (PTB) is a chronic enteritis affecting ruminants, caused by Mycobacterium avium subsp. paratuberculosis (MAP).
- Clinical suspicion of PTB prompted an investigation in a zoo population including scimitar-horned oryx, giraffes, and blue wildebeests.
Purpose of the Study:
- To evaluate the presence of MAP in a mixed ruminant collection.
- To assess the efficacy of combined diagnostic methods for PTB detection in zoo animals.
Main Methods:
- Fecal samples were collected from scimitar-horned oryx, giraffes, and blue wildebeests over several months.
- Intestine samples from necropsied scimitar-horned oryx were examined.
- MAP detection utilized bacteriology (culture, Ziehl-Neelsen staining), IS900 PCR, and anatomopathology.
Main Results:
- MAP was isolated from 12.5% of fecal samples and 40% of scimitar-horned oryx intestine samples.
- Diffuse granulomatous enteritis with acid-fast bacilli was observed in two adult scimitar-horned oryx.
- IS900 PCR confirmed MAP presence in five samples; isolates were Type C (Cattle).
Conclusions:
- MAP is present in the studied zoo ruminant population.
- Combined sampling of live animals and postmortem examinations are crucial for PTB surveillance.
- Bacteriological and histopathological techniques are vital for assessing PTB in captive wild ruminants.
