Biology Faculty Articles
Title
Semen Characteristics in Free-Living Koalas (Phascolarctos cinereus)
Document Type
Article
Publication Date
5-1-1991
Publication Title
Journal of Reproduction and Fertility
Keywords
Koala, Marsupial, Semen, Electroejaculation, Spermatozoa, Testis, Testosterone
ISSN
0022-4251
Volume
92
Issue/No.
1
First Page
99
Last Page
107
Abstract
Spermic electroejaculates (range in motile sperm/ejaculate, 0.50–122.9 × 106; mean ± s.e.m., 38.6 ± 4.9) were recovered from 47 of 48 adult koalas captured from 3 wild populations in Australia. Semen was characterized by (i) a high density of globular bodies, which prevented the estimation of sperm motility without dilution; (ii) a brownish colour; and (iii) an acidic pH. Spermatozoa were categorized on the basis of 10 head forms, most cells being a curved or hooked shape. The koala populations differed in sperm concentration and motility ratings, but not in testes size, testosterone production or proportions of spermatozoa with various head shapes. These data confirm that free-living koalas normally produce spermatozoa with a high incidence of structural heterogeneity almost solely confined to the head region; and demonstrate the utility and safety of conventional gamete and endocrine studies, approaches which will be useful for determining the impact of genetic isolation and venereal disease on species fertility.
NSUWorks Citation
Wildt, David E.; Mitch E. Bush; Stephen J. O'Brien; N. D. Murray; A. Taylor; and J. A. M. Graves. 1991. "Semen Characteristics in Free-Living Koalas (Phascolarctos cinereus)." Journal of Reproduction and Fertility 92, (1): 99-107. https://nsuworks.nova.edu/cnso_bio_facarticles/331
ORCID ID
0000-0001-7353-8301
ResearcherID
N-1726-2015
Comments
©1991 Journals of Reproduction & Fertility Ltd