Anatomical and Histological Studies on the Hyoid Apparatus and its Associated Musculature in the Domestic cat (Felis domestica)

This work was carried out on the heads of sixteen apparently healthy adult domestic cats of various sex- es. The available literatures dealing with the gross anatomy of the hyoid apparatus of various species of domestic animals were reviewed. The Manual dissection, dry bony specimens as well as histological exami- nation were used according to the purpose under investigation. The study described the six segments forming the cat hyoid apparatus; Tympanohyoideum, Stylohyoide- um, Epihyoideum, Ceratohyoideum, Basihyoideum and Thyrohyoideum.Elevenpairs of muscles where attached to the hyoid apparatus. The most enlarged of these muscles were those that retract the hyoid bone caudally, the sternohyoid muscle and rostrally, the geniohyoid muscle as well as those controlling the tongue movement, styloglossus and hyoglossus. The histological studies showed that the Tympano-hyoideum and Ceratohyoideum were mostly hyaline cartilage, the Epihyoideum was partly hyaline and partly fibrous, the Stylohyoideum and Thyrohyoideum were partly hyaline and partly osseous while the Basihyoideum was completely ossified. The results obtained were photographed, described and discussed with those of other domestic animals.