1 research outputs found
Inbreeding depression on reproductive performance and survival in captive gazelles of great conservation value
Here I present a detailed analysis of individual inbreeding coefficient effects on some
reproductive parameters and longevity in three species of gazelles under different
conservation status: vulnerable dorcas gazelle, endangered Cuvier’s gazelle, and
extinct in the wild mhorr gazelle. The novelty of this study stems from the inclusion
of both males and females in analyses including a large database of information
collected during two decades of periodical studbook inventories for these species.
Translocations to different zoo locations of the extinct subspecies mhorr gazelle do
not apparently affect reproductive performance (population sex ratio) or individual
longevity. In agreement with previous works, the average inbreeding coefficients vary
inter-specifically, being higher in Cuvier’s, followed by mhorr and dorcas gazelles.
This reflects the different population size of the founding individuals of each species’
captive population. Sexual maturity and age at first birth follow an allometric pattern,
occurring at an earlier age in the smallest species (dorcas), followed by Cuvier’s and
then the mhorr gazelle. Twinning in Cuvier’s gazelle depends on maternal experience,
as it is less frequent in primiparous females. Inbreeding affects neither twinning nor
sex ratio. Mhorr gazelles’ studbook shows several causes of death and it emerges that
a higher proportion of non-inbred females die due to pathologies than males, although
both sexes show similar proportion of mortal pathologies when inbred. Multifactor
ANOVA shows that longevity decreases with inbreeding level and that females live
longer than males in the three species of gazelles studied, as expected in polygynous
mammals. Mhorr and dorcas non-inbred females show higher juvenile survival than
males, whereas inbred individuals show a similar declining juvenile survival,
particularly in mhorr and Cuvier’s gazelles. Finally, it is discussed the apparent
3
inbreeding tolerance in Cuvier’s species, and the great value keeping and studying
long term data of well-monitored captive populations may prove to the conservation
of threatened species.Peer reviewe