Paratuberculosis or avian tuberculosis in red deer with chronic diarrhea?

Abstract

SUMMARYMycobacterium avium subsp. paratuberculosis (Map) is the etiological agent of paratuberculosis. In Chile, information about Map isolation from both domestic ruminant and wildlife species has been accumulating, but it has extended to other species. In Chile, deer farming activity has been focused in hunting and meat production. No paratuberculosis surveillance has been reported for these source herds. In the present study, chronic diarrhea and poor body condition in some animals belonging to a deer farm was informed. Four adult affected hinds were euthanized under suspicion of paratuberculosis. In all animals macroscopic and microscopic lesions consistent with paratuberculosis were observed. Map-positive culture results from faecal and tissue samples, complemented with positive-PCR-results from fixed tissues are informed. Evidence has been found on cattle and deer populations being connected since molecular characterization of the Map isolated from deer lack of variation between the cattle control strain. The latter could indicate that both species share the same bacteria, suggesting there is interspecies transmission. Complementary diagnostic methods were accurate to diagnose paratuberculosis and to differentiate the clinical deer case from other mycobacterial infection. The epidemiological findings suggest that the infection in the deer farm could be transmitted from a cattle herd, making this the first reported case of paratuberculosis in deer farm in Chile.Key words: deer, histopathology, paratuberculosis, PCR. RESUMENMycobacterium avium subsp. paratuberculosis (Map) es el agente etiológico de la patuberculosis. En Chile, antecedentes del aislamiento de Map tanto en rumiantes domésticos como en especies de vida silvestre se han ido acumulando a través del tiempo, sin embargo, esto tiene que estar afectando también a otras especies. En Chile, la crianza de ciervos se ha focalizado en dos objetivos: cotos de caza y producción de carnes exóticas, no existiendo un programa de vigilancia ni siendo reportada esta enfermedad en rebaños de este tipo. Este trabajo reporta la presencia de diarrea crónica y pobre condición corporal en algunos animales pertenecientes a una granja de ciervos donde se sospechó la presencia de paratuberculosis. Cuatro ciervos adultos fueron eutanaziados bajo esta sospecha. Todos los animales presentaron lesiones macro y microscópicas compatibles con paratuberculosis. Resultados positivos al cultivo bacteriológico a partir de heces y muestras de tejido, además de PCR a partir de tejido fijado evidencian la infección. De acuerdo a los resultados de caracterización molecular de las cepas aisladas de los ciervos que no muestran variación entre cepas control de bovino, se evidencia que ambas poblaciones estarían conectadas. Complementariamente, los métodos diagnósticos utilizados fueron muy precisos para diagnosticar paratuberculosis y para diferenciar casos clínicos en ciervos de otras micobacteriosis. Las características epidemiológicas descritas en este estudio sugieren que la infecció...

Paratuberculosis: new histopathological findings in red deer (Cervus elaphus) and fallow deer (Dama dama) in Chile

“…Macroscopic lesions were observed mainly in the small intestine (jejunum and ileum) and mesenteric LN. Thickening of the intestinal wall and increase on the size of LN was the most commonly observed feature, consistent with the findings of Balseiro et al (2008) and Pradenas et al (2014). Williams et al (1983) also coincides with the macroscopic findings in the LN, but reports that the intestine maintains a normal appearance without macroscopic alterations.…”

“…Del-Pozo et al (2013) describes an unusual case of paratuberculosis in which multifocal granulomas were found in random arrangement within the parenchyma. Very few authors reported liver damage in paratuberculosis (Mahmoud et al 2002, Paredes et al 2007, Pradenas et al 2014, probably because it is not considered a site of predilection for the disease. Only 3 animals showed AFB in the liver (cases 3.5 and 15).…”

“…Samples for histopathology were obtained and processed according to the protocol used at the Institute of Animal Pathology of the Universidad Austral de Chile (Luna 1968). Samples for genetic identification of the pathogen using rtPCR for MAP were submitted to an external lab, using a previously described protocol (Pradenas et al 2014). In samples where granulomas, epiteloid macrophages and/or giant cells were observed, Z-N staining was performed for further evaluation, thus seeking the presence of AFB.…”

“…Inflammatory infiltrate can be found in the mesenteric lymph vessels and in some extreme cases hypertrophy of smooth muscle can occur (Williams et al 1983). In some cases there are microscopic granulomas on the liver or big encapsulated granulomas containing pigment granules (Mahmoud et al 2002, Paredes et al 2007, Pradenas et al 2014. Atherosclerotic lesions in the heart and aorta have been described (Del-Pozo et al 2013).…”

Knowledge about bacterial and viral pathogens present in wild mammals in Chile: a systematic review

“…Infections with MAP have also been reported in introduced deer species in southern Chile, such as the red deer Infectología al Día (Cervus elaphus) and fallow deer (Dama dama), which could be transmitting the pathogen to livestock and vice versa 72,73 . The European wild boar (Sus scrofa) is currently distributed in rural and protected areas of south-central Chile and is considered as a carrier of MAP in Europe 74,75 .…”