Experimental infection with Yersinia pseudotuberculosis in European brown hare (Lepus europaeus, Pallas)

OBJECTIVE@#To investigate clinicopathological, bacteriological and pathological aspects of an experimental infection with Yersinia pseudotuberculosis (Y. pseudotuberculosis) in hares to verify the efficacy of serology for the in vivo diagnosis. Moreover, the pathogenicity of two Y. pseudotuberculosis strains was investigated in order to detect potential differences.@*METHODS@#Twelve European brown hares (Lepus europaeus, Pallas) were experimentally infected per os and via conjunctival mucosae with Y. pseudotuberculosis: six subjects were infected with a strain isolated from a naturally infected hare (YpH) and six subjects with a strain isolated from a naturally infected rabbit (YpR). Two hares were used as negative controls. All animals were subjected to clinical, bacteriological and serological examinations during 9 weeks following the infection and, at the end of the control period, subjects still alive were euthanized and submitted to a complete post mortem examination.@*RESULTS@#All faecal samples collected during the control period were positive for bacteriological examinations and to a PCR for the inv gene of Y. pseudotuberculosis, while only one YpH-infected hare showed a positive haemocultures. From the 2nd to the 9th week post infection (pi), serological analysis revealed specific antibodies with titers ranging from 1:10 to 1:160 in all YpH-infected and two YpR-infected subjects. All the YpH-infected and two YpR-infected hares scored positive for Y. pseudotuberculosis by means of bacteriological investigations. Grossly, suppurative multifocal lesions were detected in liver, spleen, kidney and sub-mandibular lymph nodes in both YpH- and YpR-infected hares and confirmed with histopathology. Pulmonary lesions were observed only in YpH-infected subjects. Immunohistochemistry confirmed the presence of bacterial antigen in all infected animals.@*CONCLUSION@#Results of this study revealed that YpH strain is more pathogenic for hares than the YpR strain; moreover the serological test performed in this study could be used for the diagnosis of pseudotuberculosis in hares, whereas post mortem diagnosis should be confirmed by means of bacteriological examination, PCR, histopathology and immunohistochemistry.

Experimental infection with Yersinia pseudotuberculosis in European brown hare (Lepus europaeus, Pallas)

Objective To investigate clinicopathological, bacteriological and pathological aspects of an experimental infection with Yersinia pseudotuberculosis (Y. pseudotuberculosis) in hares to verify the efficacy of serology for the in vivo diagnosis. Moreover, the pathogenicity of two Y. pseudotuberculosis strains was investigated in order to detect potential differences. Methods Twelve European brown hares (Lepus europaeus, Pallas) were experimentally infected per os and via conjunctival mucosae with Y. pseudotuberculosis: six subjects were infected with a strain isolated from a naturally infected hare (YpH) and six subjects with a strain isolated from a naturally infected rabbit (YpR). Two hares were used as negative controls. All animals were subjected to clinical, bacteriological and serological examinations during 9 weeks following the infection and, at the end of the control period, subjects still alive were euthanized and submitted to a complete post mortem examination. Results All faecal samples collected during the control period were positive for bacteriological examinations and to a PCR for the inv gene of Y. pseudotuberculosis, while only one YpH-infected hare showed a positive haemocultures. From the 2nd to the 9th week post infection (pi), serological analysis revealed specific antibodies with titers ranging from 1:10 to 1:160 in all YpH-infected and two YpR-infected subjects. All the YpH-infected and two YpR-infected hares scored positive for Y. pseudotuberculosis by means of bacteriological investigations. Grossly, suppurative multifocal lesions were detected in liver, spleen, kidney and sub-mandibular lymph nodes in both YpH- and YpR-infected hares and confirmed with histopathology. Pulmonary lesions were observed only in YpH-infected subjects. Immunohistochemistry confirmed the presence of bacterial antigen in all infected animals. Conclusion Results of this study revealed that YpH strain is more pathogenic for hares than the YpR strain; moreover the serological test performed in this study could be used for the diagnosis of pseudotuberculosis in hares, whereas post mortem diagnosis should be confirmed by means of bacteriological examination, PCR, histopathology and immunohistochemistry.

Serological survey on some pathogens in wild brown hares (Lepus europaeus) in Central Italy

OBJECTIVE@#To determine the exposure of wild brown hares [Lepus europaeus (L. europaeus), pallas] to Anaplasma phagocytophilum (A. phagocytophilum), Borrelia burgdorferi (B. burgdorferi) sensu lato, Encephalitozoon cuniculi (E. cuniculi), Leishmania sp., Neospora caninum (N. caninum) and Toxoplasma gondii (T. gondii).@*METHODS@#Two hundred twenty-two blood serum samples of wild brown hares captured in protected areas of the province of Pisa (Central Italy) were tested to detect antibodies against the reported pathogens.@*RESULTS@#Thirty one (14.0%) animals resulted positive for at least one tested agent, with antibody titres ranging from 1:20 to 1:320. In particular, 13 (5.8%) samples were positive to B. burgdorferi s.l., 11 (4.9%) to N. caninum, 3 (1.3%) to T. gondii, 2 (0.9%) to A. phagocytophilum and 2 (0.9%) to Leishmania sp. No samples scored positive to E. cuniculi. Four animals (14.8%) resulted coinfected with 2 different pathogens.@*CONCLUSION@#The obtained results showed that B. burgdorferi s.l. N. caninum, T. gondii, A. phagocytophilum and Leishmania sp. circulate in wild brown hares in Central Italy, suggesting a possible role of L. europaeus as reservoir of these pathogens. The obtained results showed that autochthonous wild brown hares living in Central Italy have been exposed to several pathogens circulating in this area, suggesting a possible role of L. europaeus as reservoir.

Serological survey on some pathogens in wild brown hares (Lepus europaeus) in Central Italy

Objective To determine the exposure of wild brown hares [Lepus europaeus (L. europaeus), pallas] to Anaplasma phagocytophilum (A. phagocytophilum), Borrelia burgdorferi (B. burgdorferi) sensu lato, Encephalitozoon cuniculi (E. cuniculi), Leishmania sp., Neospora caninum (N. caninum) and Toxoplasma gondii (T. gondii). Methods Two hundred twenty-two blood serum samples of wild brown hares captured in protected areas of the province of Pisa (Central Italy) were tested to detect antibodies against the reported pathogens. Results Thirty one (14.0%) animals resulted positive for at least one tested agent, with antibody titres ranging from 1:20 to 1:320. In particular, 13 (5.8%) samples were positive to B. burgdorferi s.l., 11 (4.9%) to N. caninum, 3 (1.3%) to T. gondii, 2 (0.9%) to A. phagocytophilum and 2 (0.9%) to Leishmania sp. No samples scored positive to E. cuniculi. Four animals (14.8%) resulted coinfected with 2 different pathogens. Conclusion The obtained results showed that B. burgdorferi s.l. N. caninum, T. gondii, A. phagocytophilum and Leishmania sp. circulate in wild brown hares in Central Italy, suggesting a possible role of L. europaeus as reservoir of these pathogens. The obtained results showed that autochthonous wild brown hares living in Central Italy have been exposed to several pathogens circulating in this area, suggesting a possible role of L. europaeus as reservoir.