Infection with the cestode Spirometra spp. was studied
in 2 populations of lions in the Serengeti and the Ngorongoro
Crater in Tanzania, East Africa. These 2 lion populations lived in different
habitats and were known to differ genetically:
lions in the Serengeti were outbred, whereas lions in the Ngorongoro Crater
were inbred. Faecal samples were collected
from 112 individually known lions between March 1991 and November 1992.
Over 60% of lions were infected and the
median intensity of infection was 975 eggs per g of faeces. The distribution
of egg counts was overdispersed. There was
variability through time, though this was unrelated to seasons delimited
by rainfall. There were no significant differences
in levels of infection between age classes; cubs less than 9 months were
already heavily infected. Sex and reproductive
status did not have a significant effect. However, there were significant
differences in intensities of infection between the
Crater and the Serengeti populations – Spirometra spp. showed
a higher level of infection intensity in the Crater population
– with some variation between prides within these populations. Allozyme
heterozygosity scores were available for a subset
of 28 lions but were unrelated to levels of Spirometra infection.
It was not possible to ascribe differences in levels of
parasite infection to genetic rather than ecological factors.
Evaluation of butorphanol, medetomidine and midazolam as a reversible narcotic combination in free-ranging African lions (Panthera leo)
