Calf sex ratio of captive eland populations

Bc. Viktor Neštický

Master's thesis

Abstract:

This Diploma thesis is focused on calf sex ratio of common elands (Taurotragus oryx) and Western Derby elands (Taurotragus derbianus derbianus). Calf sex ratio is discussed, but yet still not fully researched topic. Aim of this thesis was to test Trivers-Willard hypothesis and other possible factors affecting sex of offspring of both species. For data collection we chose 3 European institutions holding common elands with different husbandry management and 2 nature reserves in Senegal keeping the only herd of Western Derby eland in human care. Historical records from each institution holding common elands and African studbook for Western Derby eland were used for data analyses. In both species we did not recorded deviations from supposed 1:1 calf sex ratio. None of the mother's quality and her condition predicting factors had a significant impact on offspring sex with slight differences between species. Similar results were obtained from testing herd composition factors of individual groups. Significant difference was observed only in analysing impact of climatic conditions on calf sex, specifically precipitation in previous breeding season. Our results can be used for better understanding of calf sex adjustment mechanism for maximal reproductive utilization of mother's reproductive potential.

Keywords

Sex ratio, Taurotragus oryx, Taurotragus derbianus derbianus, Trivers-Willard hypothesis

Language used: English

Date on which the thesis was submitted / produced: 24. 4. 2017

Thesis defence

• Supervisor: Ing. Karolína Brandlová, Ph.D.

Czech University of Life Sciences Prague

Faculty of Tropical AgriSciences

Master programme / field:
Tropical Agriculture / Wildlife Management in the Tropics and Subtropics