A Clinical and Serological Investigation into Leptospiral Infection in Dogs and Cats

Agunloye, Caroline Adenike (1991) A Clinical and Serological Investigation into Leptospiral Infection in Dogs and Cats. MVM(R) thesis, University of Glasgow.

Abstract

CATS: This work was undertaken to determine the prevalence of leptospiral infection in cats in the Glasgow area and to assess the relationship of such serological evidence with actual disease. A total of 87 cats were sampled. Of these, 15 were pure bred and 72 were domestic cats, 46 were male and 41 female. The age range was 8 weeks to 19 years. Eight (9.2%) of the 87 cats sampled were serologically positive to three leptospiral serovars. Five (62.5%) of these cats were seropositive to Leptospira hardjo. Two (25%) were seropositive to Lautumnalis. One cat was positive to L. icterohaemorrhagiae. This is the first serological survey of leptospiral infection in cats in the Glasgow area and the first report of L. autumnalis infection in cats in the U.K. A paired serum sample demonstrated a recent infection in one of the seropositive cats. The major clinical sign shown by this cat was ascites. Active leptospiral infection could not be confirmed in the other cases. Four of the 5 cats seropositive to L. hardjo were from rural areas. This confirmed that a small proportion of the cat population does become infected with leptospirae and that this may occasionally result in clinical disease. In view of the lack of a definitive disease description of leptospiral infection in cats, there is need for further studies into this disease. In addition, there is a need to investigate the factors which may predispose to leptospiral disease in cats. DOGS: One hundred and fifty dogs from the Glasgow area were examined for antibodies to 11 leptospiral serovars and also for clinical signs of infection. This was to determine the prevalence and types of leptospiral infection in both vaccinated and unvaccinated dogs. Seventy-two of the dogs were male and 78 were female. One hundred and thirty eight were pure bred and 12 were crossbred. Ages ranged from 8 weeks to 14 years. Twenty nine (19.8%) of these dogs had positive leptospiral titres to 5 leptospiral serovars. Eighteen (48.6%) of the seropositive dogs reacted to L. icterohaemorrhagiae. 9 (24.3%) to L. bratislava. 8 (21.6%) to L. canicola. One was positive to L. hardjo. Sixteen of the seropositive dogs were male and 13 were female with an age range from 24 weeks to 12 years. Seventy two (48.0%) of the sampled population had been vaccinated and in most cases revaccinated within the previous 12 months (Group A). Of these, only 15 (20.8%) had antibody titres to leptospiral antigens. Eight (47.1%) showed a positive reaction to L. icterohaemorrhagiae. 5 (29.4%) were seropositive to L. canicola. 2 had antibodies to L. bratislava and one was positive to L. hardjo. Fifty six of the 150 dogs (37.4%) had been initially vaccinated against leptospirosis but not revaccinated within the previous 12 months (Group B). Of these, 7 (12.5%) had antibodies to leptospiral antigens. They were variously positive to L. icterohaemorrhagiae, L. canicola and L. bratislava. However, there is no significant difference (P>0.5) in the number of seropositive dogs in groups A and B. Six adult dogs in the sampled population had been recently vaccinated (Group C). Four had positive leptospiral antibodies to L. icterohaemorrhagiae and L. bratislava and were from the same kennel. Sixteen (10.7%) of the 150 dogs had never been vaccinated against leptospirosis or had an unknown vaccination history (Group D). Of these, 3 (18.8%) had positive leptospirai titres. Two were positive to L. icterohaemorrhagiae and one to L. bratislava. Of the seropositive dogs, 2 had evidence of active infection with leptospiral organisms, one from Group B and the other from Group D. The former, an imported dog, (vaccinated, but not known to have been revaccinated within the previous 12 months,) had a high antibody titre to L. icterohaemorrhagiae and classical signs of leptospirosis. This study confirmed that not all fully vaccinated dogs have antibody to leptospiral antigens, as detected by the microscopic agglutination test (MAT), to bacterin serovars. Also, vaccinated animals are not free from infection with bacterin and non-bacterin serovars and illness is possible in vaccinated dogs, although the risk of infection is lower. Unvaccinated and inadequately vaccinated dogs are at greater risk of developing active infection. In this work a large proportion of seropositive dogs had antibodies to the Australis group, a non-vaccine serovar. There is need for further work to associate such infections with disease to provide a basis for improving future vaccination programmes.

• Item Type: Thesis (MVM(R))
• Qualification Level: Masters
• Keywords: Veterinary science, Animal diseases
• Date of Award: 1991
• Depositing User: Enlighten Team
• Unique ID: glathesis:1991-78291
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 30 Jan 2020 15:34
• Last Modified: 30 Jan 2020 15:34
• URI: https://theses.gla.ac.uk/id/eprint/78291