Anatomical characteristics of digestive tract in rabbit fish (Siganus javus) of Persian Gulf

Rabbit fish (Siganus javus) is a valuable species and is considered a potential fish for aquaculture.. Macroscopic and microscopic studies of tissues facilitate the development of biologic and histopathologic knowledge about the species. This study investigates the anatomical feature of digestive tract and histological characteristics of esophagus in rabbit fish through the necropsy of 10 rabbit fish and subsequent 10% formaldehyde solution fixation and tissue processing of esophagus for H&E staining protocol. The length of digestive tract was 45±5 cm (mean ± SD) which comprised oral cavity, throat, esophagus, stomach, pyloric caeca, duodenum, jejunum, caudal part, rectum and the ending part of intestine. Two appendixes called pyloric caeca were observed at the endof stomach. Microscopic studies of esophagus revealed four layer structure composed of mucosa, sub mucosa, muscularis layer and serosa. A numerous spiral folding existed in the mucosal part which surrounded the lumen of the tube and were covered by stratified squamous cell epithelium.