Abstract

Skin samples removed from sheep foetuses at weekly intervals during gestation were studied to examine how between breed differences in follicle development are induced. Immunocytochemical methods were used to examine the localisation of the peptide transforming growth factor-Beta1 (TGFb1 ). Our observations indicate general localisation of TGFb1 in the skin between 83 and 104 days of gestation in both Romney and Merino breeds. This coincides with the maturation of primary follicles and the development of sebaceous and sweat glands. TGFb1 immunoreactivity was maintained in primary follicles (particularly the presumptive inner root sheath cells in lower regions of the bulb), sweat gland and sebaceous gland but by day 134, a more discrete localisation was observed in the inner root sheath (IRS), outer root sheath (ORS) and sebaceous gland with intense immunoreactivity in the sweat gland. The timing of the localisation and the lack of difference between the breeds suggest that variation in the TGFb1 level is unlikely to have a regulatory role in primary and secondary follicle initiation but may play a role in regulating the diverse differentiation pattern of various cell types within the follicle. The intense immunoreactivity in mature sweat glands suggests a possible osmoregulatory role for TGFb1 in the skin.

JE, Hocking-Edwards, DG Thomas, MJ Birtles, PM Harris, SN McCutcheon, and GA Wickham

Proceedings of the New Zealand Society of Animal Production, Volume 57, , 51-56, 1997