Veterinarni Medicina, 60, 2015 (2): 101–104 Case Report doi: 10.17221/7984-VETMED Avian mycobacteriosis in an individual of the endangered Mauritian Pink pigeon (Nesoenas mayeri) species: a case report P. Kriz1, J. Makovcova1, M. Skoric2, O. Huml3, J. Pokorny4 1Veterinary Research Institute, Brno, Czech Republic 2University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic 3VEDILAB Ltd., Plzen, Czech Republic 4Zoological and Botanical Garden Plzen and Veterinary Office StarVet, Stary Plzenec, Czech Republic ABSTRACT: Avian mycobacteriosis was diagnosed in one female Mauritian Pink pigeon (Nesoenas mayeri) from a zoological collection. The bird displayed clinical symptoms of apathy, loss of body weight, ruffled feathers and diarrhoea. Necropsy revealed nodular lesions in the internal organs. Mycobacterium avium subsp. avium was isolated and also directly detected using qPCR in the female’s liver. Avian mycobacteriosis may pose a threat to efforts directed towards conservation of this endangered species. Keywords: Columba; conservation; dove; tuberculosis Avian mycobacteriosis is a chronic infectious and the release of birds into the wild. Further cap- disease of both domestic and wild birds character- tive subpopulations of Mauritian Pink pigeons have ised by a long incubation period and non-specific been established in many zoological collections clinical symptoms, e.g. wasting, loss of weight to around the world. Avian mycobacteriosis caused emaciation and diarrhoea; and the occurrence of by M. a. avium has been occasionally observed in microscopic and/or macroscopic granulomatous various columbids (Saggese et al. 2008; Kriz et al. inflammatory lesions (tuberculous lesions) in vari- 2011); however, according to the available literature ous organs. Several species of mycobacteria can it has not yet been described in Mauritian Pink be causative agents of this disease. Mycobacterium pigeons. avium complex members (M. a. avium and M. a. hominissuis) have been frequently isolated from infected birds (Shitaye et al. 2009; Kriz et al. 2011). Case description The Mauritian Pink pigeon (Nesoenas mayeri) is an endemic columbid species which has survived A three year and six months old female Mauritian on the Island of Mauritius in the western Indian Pink pigeon from a zoological collection in the Ocean. Although critically endangered by extinc- Czech Republic was presented to a veterinarian tion in the early 1990’s with a mere 10 individuals because of impaired body condition. During the remaining, the wild population of Pink pigeons first presentation, the bird showed inappetence, gradually increased to more than 440 individuals apathy and ruffled feathers. Marbofloxacine 10 mg/ in 2011 due to an intensive conservation program. kg i.m. SID (intramuscular injection, single in a day Key components of the program include captive dosage), (Marbocyl 20 mg/ml inj., Vetoquinol s.r.o., breeding both in Mauritius and at the Jersey Zoo Nymburk, Czech Republic) was administered for Supported by the Ministry of Education, Youth and Sports of the Czech Republic under the NPU I Program (Project No. LO1218). 101 Case Report Veterinarni Medicina, 60, 2015 (2): 101–104 doi: 10.17221/7984-VETMED one week and the clinical status of the bird gradu- The necropsy revealed a grey-to-yellowish nodu- ally got better. However, the condition of the bird lar lesion growing from the body cavity through the worsened over the subsequent ten days after the breast bone. Multiple grey-to-yellowish nodular le- cessation of the therapy. At the second presenta- sions of 1 to 15 mm were seen in the liver (Figure 2), tion the bird weighed 220 g (normal body weight as well as in the kidneys and the intestinal wall. of adult female pink pigeon is about 315 g), and Samples were collected from all these organs and displayed apathy, inappetence, and ruffled feathers. were fixed in buffered 10% neutral formalin, dehy- Parasitological examination of faeces was negative. drated and embedded in paraffin wax. The samples Antimicrobial therapy using marbofloxacin was were then sectioned on a microtome and stained started again but no response was observed over with haematoxylin and eosin and according to the subsequent days. Ziehl-Neelsen (ZN). A firm nodule (2 cm in diameter) was found The sample of liver (1 g) was homogenised and by palpation on the right side of the breast bone decontaminated using the HCl-NaOH method under the breast muscle. Radiographical exami- according to a procedure described previously nation confirmed the presence of a radiolucent le- (Fischer et al. 2000). Each decontaminated sample sion on the right side of the breast bone (Figure 1). was inoculated onto Herrold’s egg yolk medium Clinical haematology performed using standard- and Löwenstein-Jensen with sodium pyruvate in ised methods revealed leucocytosis (39.6 × 109/l) duplicate and then incubated at 37 °C. Suspected caused by heterophilia (30.8 × 109/l) and mono- colonies were checked using ZN staining and cytosis (7.1 × 109/l). Markedly increased activities then subcultured on Herrold’s egg yolk medium. of creatine phosphokinase (CPK; > 2000.66 IU/l), Obtained colonies were again stained according to aspartate aminotransferase (AST; 584.9 IU/l) and ZN and subsequently identified using a multiplex lactate dehydrogenase (LDH; >901.65 IU/l) were PCR method described previously (Moravkova et found during biochemical analysis of blood (Fuji al. 2008). Dry-Chem 4000i, Fujifilm Europe GmbH, Prague, Direct detection and quantification of mycobac- Czech Republic). The bird was put on a therapy terial DNA from the liver sample was performed of Meloxicam 1 mg/kg s.c. SID (subcutaneus in- using an isolation procedure with a commercially jection), (Metacan 5 mg/ml inj., Boehringer available kit and the DNA was detected and quan- Ingelheim Vetmedica GmbH, Ingelheim am Rhein, tified using a triplex quantitative real time PCR Germany) and phenoxymethylpropionate 10 mg/kg previously described by Slana et al. (2010). i.m. SID (Hepagen inj., FATRO S.p.A. – Industria Multiple foci of chronic nodular granuloma- Farmaceutica Veterinaria, Ozzano Emilia, Bologna, tous inflammation with central necrosis and mac- Italy); however, on the eighth day of therapy the rophages in the centre and lymphocytes on the health condition worsened dramatically with the periphery were seen in the tissue sections. Multiple occurrence of diarrhoea and the bird died. giant multinucleated cells of the Langhans’ type Figure 1. Radiolucent lesion (arrow) on the right side of Figure 2. Multiple grey-to-yellowish nodules in the liver the breast bone and intestine 102 Veterinarni Medicina, 60, 2015 (2): 101–104 Case Report doi: 10.17221/7984-VETMED were present on the periphery of the lesions. The sure on the breast muscle. Increased levels of AST structure of all the organs was markedly affected can be explained by the destruction of the liver by the multiple lesions. ZN staining showed the parenchyma by multiple tubercles. presence of acid-fast bacilli (AFB). The survival of the wild population of Mauritian Culture of liver yielded a M. a. avium isolate and Pink pigeons is endangered by several factors, e.g., M. a. avium was found in numbers of 5.16 × 107 cells introduced predators, shortage of native habitats per one g of liver sample, as determined using qPCR. and food, regular occurrence of cyclones, inbreeding and infections (Swinnerton et al. 2004). The nega- tive impact of trichomoniasis (Trichomonas galli- DISCUSSION AND CONCLUSIONS nae) as well as leucocytozoonosis (Leucocytozoon marchouxi) on the wild Pink pigeon population on Tuberculous lesions in the liver, as well as the Mauritius is well documented (Swinnerton et al. spleen and intestine have been frequently detected 2005; Bunbury et al. 2008). in columbids with M. a. avium infection/disease, According to available literature, avian myco- although many other tissues and organs have been bacteriosis has yet to be reported either in cap- affected occasionally, e.g., lungs, air sacs, kidneys, tive or in wild Mauritian Pink pigeons. Thus, it gonads, bone marrow, etc. (Saggese et al. 2008; Kriz is not possible to draw any conclusions regarding et al. 2011). The localisation of tuberculous lesions the significance of M. a. avium infection for this in the female bird described here suggests an oral species. However, the insidious character of the route of infection with subsequent dissemination disease accompanied by a lack of both rapid and of the causative agent through the gastrointestinal reliable ante-mortem diagnostic methods and ef- tract into the parenchymatous organs. fective therapy may pose a threat to efforts made Typical histopathological pictures of granuloma- in the framework of the conservation program for tous inflammatory reaction and AFB were observed Mauritian Pink pigeons. in the liver, as well as intestine and kidneys. The nodule growing through the breast bone of the bird was most probably of the same aetiology but un- Acknowledgements fortunately, it was not sent for histopathology or culture. A tuberculous lesion growing through the The authors acknowledge Iva Bartejsova (Veterinary breast bone has not been reported in columbids yet. Research Institute, Brno, Czech Republic) for Most probably, the primary focus was the serosal her technical assistance and Jaroslav Vogeltanz surface in the body cavity after dissemination of (Zoological and Botanical Garden Plzen, Plzen, M. a. avium from the intestine. Czech Republic) for the kindly provided photo- As there were no available reference values graphs. Neysan Donnelly (Max Planck Institute of for interpretation of clinical haematology and Biochemistry, Munich, Germany) is thanked for the biochemistry of Mauritian Pink pigeons, more grammatical correction of the manuscript. general reference data from birds of the order Columbiformes had to be used (Gayathri et al. 2004; Prinzinger and Misovic 2010). Thus it was REFERENCES necessary to perform very careful interpretation. 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