Endoscopy of the gastrointestinal tract
Endoscopy can be used to evaluate oesophageal and gastric disease in tigers. In mid- sized and adult tigers endoscopes will not be long enough to reach the duodenum.
The tiger should be anaesthetised and placed in left lateral recumbency with the head and neck extended. A mouth gag should be fitted to avoid damage to the endoscope (this could be a simple length of slim plastic pipe between upper and lower canines). The tip of the endoscope should be lubricated (avoiding the lens). The scope should then be passed along the midline of the hard palate into the pharynx and then along to the oesophageal sphincter. The endoscope should be advanced slowly down the oesophagus, keeping the entire mucosal circumference in view and whilst insufflating with air. At the cardiac sphincter of the stomach the endoscope should be gently advanced and the stomach then inflated with a moderate amount of air to allow orientation. Any abnormal areas can be sampled using the biopsy attachment of the endoscope. The biopsy forceps should be passed down the endoscope’s biopsy channel with the cup firmly closed. The cup should be opened once the forceps are out of the end of the scope, positioned onto the mucosa, closed and the forceps then withdrawn. Samples should be placed in 10% formalin for histopathology.