Abstract
Electromyographic studies on the deglutition movement were carried out with ten adult fowls. In the unanesthetized fowls, bipolar electrodes of 120μ enamel-covered copper wire were inserted into 13 muscles of the throat and the esophagus. The deglutition reflex was elicited by tactile stimulation of the tip of the tongue with a wet cotton swab. In the fowl, the deglutition movements were rapid rostro-caudal tongue movements. Tonic activities were seen in the m. hyoglossus and the m. styloentoglossus during the deglutition. These muscles concaved the hyoid apparatus ventrally. The m. stylomandibularis and the m. laryngohyoideus acted synchronously in such manner as to pull the hyoid apparatus backward in each movement. The m. articulohyoideus dorsalis and ventralis and the m. transversus hyoideus acted to restore the hyoid apparatus after the activities of the m. stylomandibularis and the m. laryngohyoideus. From the results, the muscles connecting the mandible or the larynx with the hyoid apparatus and those adhering to this apparatus were known to play an essential role to move the hyoid apparatus with the tongue at the time of deglutition in fowls.
