Clinical, haematological and biochemical findings in tigers infected by Leishmania infantum
Background A large number of animal species are susceptible to Leishmania infantum (Kinetoplastida, Trypanosomatidae) in endemic areas, including domestic and wild felids such as tigers (Panthera tigris). Knowledge on the infection of this endangered species is still at its infancy, and therefore this study aims to identify clinical presentation and clinicopathological findings of tigers naturally infected by L. infantum.
Results Tigers either L. infantum-positive (group A) or -negative (group B) were apparently healthy or presented visceral leishmaniasis unrelated conditions, except for one animal in which a large non-healing cutaneous lesion was observed. However, histological exam and immunohistochemistry carried out on the lesion excluded the presence of L. infantum amastigotes. Biochemical analysis showed that the average concentration of total proteins, globulins and haptoglobin were significantly higher (p<0.01, p=0.01 and p=0.02, respectively), while the albumin/globulin ratio significantly lower (p=0.05) in group A compared with group B. The biochemical alterations were partially confirmed by the serum protein electrophoresis results revealing a significant increase in the total protein value (p=0.01) and hypergammaglobulinemia (p=0.03) but an unmodified albumin/globulin ratio in group A.
Conclusions In this study tigers infected by L. infantum have shown to be mainly asymptomatic. The absence of clinical signs may lead veterinarians to overlook leishmaniasis in animals kept in captivity. Therefore, diagnostic and screening tests as serology should be part of routinely surveillance programs to be performed on tigers in zoological gardens located in endemic areas. Though only few protein-related laboratory abnormalities were recorded in infected animals, they could provide diagnostic clues for a first suspicion of L. infantum infection in tigers. Indeed, considering the high risk of zoonotic transmission in heavily frequented environment as zoos, a prompt diagnosis of L. infantum infection is of pivotal importance.
Posted 05 Jun, 2020
On 22 Jun, 2020
On 05 Jun, 2020
On 31 May, 2020
On 30 May, 2020
On 30 May, 2020
On 22 May, 2020
On 15 Apr, 2020
On 14 Apr, 2020
On 14 Apr, 2020
On 12 Apr, 2020
Received 11 Apr, 2020
On 24 Mar, 2020
Received 22 Mar, 2020
On 19 Feb, 2020
Invitations sent on 12 Feb, 2020
On 10 Feb, 2020
On 04 Feb, 2020
On 03 Feb, 2020
Clinical, haematological and biochemical findings in tigers infected by Leishmania infantum
Posted 05 Jun, 2020
On 22 Jun, 2020
On 05 Jun, 2020
On 31 May, 2020
On 30 May, 2020
On 30 May, 2020
On 22 May, 2020
On 15 Apr, 2020
On 14 Apr, 2020
On 14 Apr, 2020
On 12 Apr, 2020
Received 11 Apr, 2020
On 24 Mar, 2020
Received 22 Mar, 2020
On 19 Feb, 2020
Invitations sent on 12 Feb, 2020
On 10 Feb, 2020
On 04 Feb, 2020
On 03 Feb, 2020
Background A large number of animal species are susceptible to Leishmania infantum (Kinetoplastida, Trypanosomatidae) in endemic areas, including domestic and wild felids such as tigers (Panthera tigris). Knowledge on the infection of this endangered species is still at its infancy, and therefore this study aims to identify clinical presentation and clinicopathological findings of tigers naturally infected by L. infantum.
Results Tigers either L. infantum-positive (group A) or -negative (group B) were apparently healthy or presented visceral leishmaniasis unrelated conditions, except for one animal in which a large non-healing cutaneous lesion was observed. However, histological exam and immunohistochemistry carried out on the lesion excluded the presence of L. infantum amastigotes. Biochemical analysis showed that the average concentration of total proteins, globulins and haptoglobin were significantly higher (p<0.01, p=0.01 and p=0.02, respectively), while the albumin/globulin ratio significantly lower (p=0.05) in group A compared with group B. The biochemical alterations were partially confirmed by the serum protein electrophoresis results revealing a significant increase in the total protein value (p=0.01) and hypergammaglobulinemia (p=0.03) but an unmodified albumin/globulin ratio in group A.
Conclusions In this study tigers infected by L. infantum have shown to be mainly asymptomatic. The absence of clinical signs may lead veterinarians to overlook leishmaniasis in animals kept in captivity. Therefore, diagnostic and screening tests as serology should be part of routinely surveillance programs to be performed on tigers in zoological gardens located in endemic areas. Though only few protein-related laboratory abnormalities were recorded in infected animals, they could provide diagnostic clues for a first suspicion of L. infantum infection in tigers. Indeed, considering the high risk of zoonotic transmission in heavily frequented environment as zoos, a prompt diagnosis of L. infantum infection is of pivotal importance.