A technique for long-term small artery cannulation for studies on wool growth

Abstract

Extract

Sir:- Current knowledge of the biological features of the wool fibre and follicle has recently been reviewed by Chapman and Ward.(1) Understanding the control of wool growth involves and understanding of the function of the wool follicle and detailed knowledge is lacking in a number of important areas. Mature wool follicles cannot be cultured in vitro.. Studies have been largely restricted to whole-animal experiments which have measured wool growth response to feeding regime; or infusion into the abomasum or injection, typically into the jugular vein, of compounds of interest. These techniques provoke a whole-animal response and fail to clarify direct effects at the follicle level. Furthermore, there is no internal control for the experiments. As wool growth varies with day length and other influences, pre- and post-experiment data have limitations for comparative control purposes.