Proceedings of the First Symposium on Marsupials in New Zealand
Results
Results
A high prevalence of Hebdomadis serogroup reactions was revealed in the pastoral possum populations sampled, with 60 of 127 sera (47%) positive to Hebdomadis antigens. Serovar hardjo antigen gave a consistently higher titre when compared with balcanica antigen in all sera tested. No cross-reactions were seen with antigens from other serogroups.
page 160There was a marked age differentiation in serological prevalence with mature adults having the highest prevalence, and only one juvenile animal being positive at a low titre (Table 2).
SUBGROUP | NO. COLLECTED | NO. SEROPOSITIVE TO HEBDOMADIS ANTIGEN (%) | NO CULTURE POSITIVE (%) | NO. SERO. AND/OR CULTURE POSITIVE (%) | |||
---|---|---|---|---|---|---|---|
Mature male | 32 | 25 | (78) | 23 | (72) | 28 | (86) |
Mature female | 32 | 22 | (69) | 18 | (56) | 26 | (81) |
Trans. stage male | 15 | 7 | (47) | 4 | (27) | 7 | (47) |
Trans. stage female | 18 | 5 | (28) | 3 | (17) | 5 | (28) |
Juvenile male | 15 | 0 | (0) | 0 | (0) | 0 | (0) |
Juvenile female | 15 | 1 | (7) | 0 | (0) | 1 | (7) |
Total | 127 | 60 | (47) | 48 | (38) | 67 | (53) |
Leptospiral isolations were made from 48 of 127 animals sampled (38%). All were typed against standard antisera in our laboratory as belonging to the Hebdomadis serogroup. Eight isolates were forwarded to the W.H.O. Reference Laboratory in Atlanta, U.S.A. for serovar identification. All eight isolates were found to be serovar balcanica.
A marked age differentiation was seen in cultural prevalences with all isolations being from sexually mature adults (Table 2). Isolates were obtained from 41 of 64 mature adults (64%) and from 7 of 33 transitional-stage adults (21%).