Introduction of a Permanent Electrode into the Pituitary Gland of the Cow: Influence of Electrical Stimulation on Milk Ejection

Abstract

PROCEDURES involving intervention with the pituitary gland or the hypothalamus, in the investigation of their influence on lactation, have mainly been carried out on small laboratory animals. Few experiments of this kind have been performed on ruminants; most of these were on goats and the remainder on sheep. This type of procedure has been extended to the cow by a process which we have described elsewhere1. Essentially, the method consists of inserting a specially adapted needle through the skin and through the muscular part of the tongue to the pharynx, where the operating worker, with his hand in the oral cavity of the animal, places the tip of the needle in a defined position on the sphenoid bone. By means of a drill which operates through the guiding needle, he drills through the sphenoid bone to the pituitary gland. In this way it is possible to carry out the application of various substances to the pituitary with the view of destroying it, or of carrying out biopsy of the pituitary gland, or of collecting blood from the sinus cavernosus.