University of Veterinary Medicine Vienna - Research portal

Diagrammed Link to Homepage University of Veterinary Medicine, Vienna

Selected Publication:

Open Access Logo

Publication type: Doctoral Thesis

Year: 2011

Author(s): Hubmer, Ines

Title: Rank of female and sex of fetus influence reproductive endocrinology of pregnant and post-partum elands (Taurotragus oryx) in captivity.

Other title: Rangordnung des Muttertieres und Geschlechtsausprägung des Fötus als Einflussfaktoren auf die Reroduktionsendokrinologie trächtiger bzw. post-partum Elenantilopen (Taurotragus oryx)

Source: Dissertation, Vet. Med. Univ. Wien, pp. 62.


Advisor(s):

Schwarzenberger Franz

Reviewer(s):
Walzer Christian

Vetmed Research Units:
Institute for Medical Biochemistry


Graduation date: 03.03.11


Abstract:
The eland (Taurotragus oryx), a common African species of antelope, is of interest for potential domestication for meat, milk and leather production. This study investigated the reproductive endocrinology of pregnant and post-partum elands (n = 10). Freshly defecated fecal samples were collected after observed defecation. Blood samples were obtained using blood sucking bugs (Dipetalogaster maxima) and by vein puncture of a coccygeal blood vessel. Fecal steroid hormone metabolites (estrogenes, 20-oxo-pregnanes - 20-oxo-P, pregnandiol - 20􀄮-OH-P, glucocorticoid, testosterone and epiandrosterone) and blood hormones (progesterone, corticosterone and cortisol) were analyzed using enzymeimmunoassay. The hormones and metabolites were associated to dominance rank of females and sex of fetus. Gestation length 259,7 ± 1,8 days (Mean ± SEM) was significantly shorter in higher than in lower ranking females. Fecal 20-oxo-P levels during gestation revealed a biphasic pattern, with peak hormone production during the first and the last trimester. 20-oxo- P production during the first trimester was higher, and of shorter duration in females that held a higher status within the herd. Before parturition those females had higher testosterone and estrogen, but lower progesterone and cortisol metabolite levels. Eland females carrying a male fetus had higher testosterone and 20-oxo-P metabolite levels before parturition. Regular estrous cycles (19,0 ± 0,92 days) during the post partum period were detected in the most dominant females only. Nonetheless all females became pregnant within two weeks after the breeding bull was introduced to the herd. Steroid hormone levels in blood samples taken with a conventional needle versus blood sucking bugs did not reliably correlate; plasma progesterone and corticosterone levels from bugs were significantly higher. The reproductive endocrinology of pregnant and post partum elands seems to be closely related to dominance hierarchy; in addition hormone production during the last month of gestation is affected by the gender of the fetus.


© University of Veterinary Medicine ViennaHelp and Downloads