Gross morphology and scanning electron microscopy of the Bagrus Bayad (Forskal, 1775) oropharyngeal cavity with emphasis to teeth-food adaptation.

Bagrus Bayad (Forskal, 1775) is a bottom feeder fish feeds on different food items. Its oral cavity anatomy has many types of teeth adapted to the capacity and varieties of feeding. The aim of the present study was to use the gross anatomy and scanning electron microscopy to identify the anatomical characteristic, especially of the teeth and taste buds distributed on the roof and floor of the oropharyngeal cavity. The results clarified that Bagrus Bayad has two types of teeth; curved pointed and blunt teeth of different sizes. The teeth appeared on epithelial protrusions. The pharyngeal region had upper and lower pharyngeal teeth, the upper arranged into two oval prominences while the lower ones arranged into two triangular areas. The higher number of the pointed teeth is prove the carnivorous nature of the Bagrus Bayad. Three types of taste bud (I, II, & III) were found in the oropharyngeal cavity. The tongue present in the floor and free from teeth and characterized by the presence of taste bud type I and II. Many microridges of different arrangement observed on the surface epithelium of oropharyngeal cavity. The upper and lower valve characterized by the microridges, pores and taste buds. The knowledge of the nature of the oropharyngeal cavity of the Bagrus Bayad helps in identifying new and better methods for feeding in aquaculture.