The electromyographic activity of intrinsic laryngeal muscles during quiet breathing in the anaesthetized horse

Authors: Barnes GRG, Quinlan TJ, Goulden BE
Publication: New Zealand Veterinary Journal, Volume 24, Issue 8, pp 157-162, Aug 1976
Publisher: Taylor and Francis

Animal type: Horse, Livestock
Subject Terms: Anaesthesia/analgesia/sedation, Animal remedies/veterinary medicines, Ear/nose/throat, Disease/defect, Respiratory system
Article class: Scientific Article

---

Abstract: Electromyographic examination of intrinsic laryngeal muscular activity has been carried out in man (Faaborg-Anderson, 1957) and some experimental animals including the cat (Grelen and Neil, 1955; Rex, 1969), dog (Nakamura et al 1958; Siribodhi et al 1963), goat (Murtagh and Campbell, 1954) and monkey (Lund and Palmer, 1969). The purpose of these investigatioas has been to increase understanding of the action of the laryngeal muscles and to provide a basis on which to compare the normal individual with those suffering from neurogenic and myogenic disorders of the larynx. The writers are unaware of any electromyographic studies on equine laryngeal musculature. This is surprising since the horse is very commonly affected by laryngeal muscular disease (Duncan et al 1974). During quiet respiration in the majority of horses there are some movements of the laryngeal cartilages. These movements are due to the action of the intrinsic laryngeal muscles. However, the part played by individual muscles resulting in laryngeal cartilage movements is not fully understood. The aim of the present study is to determine the electrical activity within the intrinsic laryngeal muscles in anaesthetized horses and thereby provide information on the action of each of these muscles and, in addition, to establish a normal electromyographic pattern with which further studies on animals exhibiting signs of recurrent laryngeal paresis could be compared.

---