Genotyping and comparative pathology of Spirocerca in black-backed jackals (Canis mesomelas) in South Africa

BMC Veterinary Research

Research Article

P. J. de Waal¹  J. Mitha¹  G. T. Fosgate²  H. Lutermann³  M. C. Williams⁴  M. M. Bumby⁴  S. J. Clift⁴  J. C. A. Steyl⁴  R. Harrison-White⁵ 

[1] Department of Genetics, University of Pretoria, 0002, Pretoria, South Africa;Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Private bag X04, 0110, Onderstepoort, South Africa;Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Private Bag X20, Hatfield, 0028, Pretoria, South Africa;Section Pathology, Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Private bag X04, 0110, Onderstepoort, South Africa;Wildlife Damage- Research and Management, North West Parks and Tourism Board, Madikwe and SA Lombard Nature Reserves, North West province, South Africa, P.O. Box 783540, Sandton, 2146, Johannesburg, South Africa;

关键词: Aortic aneurysms;    Black-backed jackal;    Genotyping;    Esophageal nodule;    Resistance;    Spirocerca lupi;    Spirocercosis;   

DOI  :  10.1186/s12917-017-1175-4

 received in 2016-10-02, accepted in 2017-08-09,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundThe pathology of spirocercosis, a disease caused by the infestation of carnivores with the nematode Spirocerca lupi, has been extensively described in domestic dogs and coyotes. However, it has not been described in wild carnivores in South Africa. The aim of this study was to evaluate whether black-backed jackals are a host for Spirocerca species and to provide a detailed description of the associated pathology. Jackals were also stratified according to age and the Spirocerca species recovered were characterized using molecular techniques.MethodsStandard necropsies were performed on routinely culled jackals from three of the nine provinces of South Africa during the period June 2012 to February 2013. Jackals were screened for the presence of pathognomonic Spirocerca-induced lesions and for evidence of aberrant migration. Relevant samples were submitted for histopathology and collected larvae were genotyped at nine microsatellite loci.ResultsSpirocerca lupi-associated aortic lesions were found in 16 of 93 (17%) black-backed jackals. Of these, four (25%) were associated with S. lupi larvae. Genotyping of the larvae revealed amplification of all nine loci that amplified dog-derived S. lupi, with the same level of polymorphism in the allele size ranges. Only 1 of 93 jackals had an esophageal nodule with concurrent S. lupi-induced aortic aneurysms. The single esophageal nodule found did not contain adult nematodes, nor did it communicate with the esophageal lumen. None of the jackals that were examined had macroscopically evident spondylitis, which is frequently reported in the dog.Histopathology of the S. lupi-induced aortic lesions in the jackal revealed replacement of elastic and smooth muscle fibers by fibrous connective tissue. In cases where inflammation was present, the inflammatory infiltrate consisted predominantly of eosinophils. The single esophageal nodule histologically resembled the early inflammatory nodule described in dogs and consisted of fibrous connective tissue, multifocal accumulation of lymphocytes, plasma cells and rare hemosiderin-laden macrophages.ConclusionsThese lesions suggest that the life cycle of S. lupi may not or only rarely be completed in jackals. A possible explanation might be that jackals are relatively resistant to developing significant pathology associated with S. lupi-infection. However, before any conclusions can be drawn, many more jackals, including those that die naturally will have to be investigated for evidence of S. lupi infection.

【 授权许可】

CC BY   
© The Author(s). 2017