Metabolism of Testosterone by Forehead Skin of the Roebuck (Capreolus Capreolus)

Abstract

Roebucks have a specialized region of skin on the forehead which contains sebaceous and apocrine glands that produce secretions used in territorial marking. These glands enlarge during the breeding season and regress after the rut as the testes regress. The metabolism of testosterone by this forehead skin in vitro was studied in two captive roebucks over the period of glandular enlargement and subsequent regression, and compared with that of dorsal skin. In May, June and July, both areas of skin actively metabolized testosterone and the metabolites detected were androstenedione, androstanedione, dihydrotestosterone, epiandrosterone, androsterone and 5alpha-androstanediols. There were no major differences in testosterone metabolism between the two body sites, although dorsal skin appeared to be more active in total metabolism than forehead skin. There was a peak in the extent of metabolism in June/July, with a subsequent gradual decline to December. The decline in metabolism occurred at a time when the associated glands were still enlarged, which suggests that the availability of androgen to the skin glands is determined not only by the amount of testosterone in the circulation, but also by a decrease in the metabolizing capacity of the tissue.

Cutaneous glands of male and female impalas ( Aepyceros melampus ): seasonal activity changes and secretory mechanisms

“…The observed morphological changes, e.g., increased cell height, increased number of cell organelles, increased expression of cytokeratins, increased amounts of secretory products, specific nuclear morphology, and the formation of multinuclear cells, are interpreted to be an effect of high testosterone levels. Our observations fundamentally agree with findings on testosterone metabolism by forehead skin of the roebuck (Johnson and Leask 1977).…”

Distribution of Deer Keds (Diptera: Hippoboscidae) in Free-Living Cervids of the Tuscan-Emilian Apennines, Central Italy, and Establishment of the Allochthonous Ectoparasite Lipoptena fortisetosa

“…Additionally, in C. elaphus, there are quantitative and qualitative differences between males and females in terms of their released compounds [64]. As reported by Johnson and Leask [65] for C. capreolus, glandular activity and active testosterone metabolism can increase just prior to and during the mating season. In Italy, the breeding season of red deer occurs from late summer to early fall, overlapping with the host seeking period of L. cervi, possibly affecting the preference of the parasite for males.…”