Histological and histochemical studies of the gastrointestinal tract in the water monitor lizard (Varanus salvator)

The histological and histochemical studies of gastrointestinal tract (GI tract) are important for understanding the morphophysiology in animal digestive processes. Therefore, this study aimed to describe and analyse the histological and histochemical characteristics of Varanus salvator GI tract based on two adult wild-caught specimens (male and female). The results of histological study revealed that most of V. salvator GI tract is quite similar to that of other vertebrates. However, only slight differences were found in some histological aspects. According to the fine structure of stomach, the oxynticopeptic cells of oral fundic region contained numerous secretory granules, while those of the aboral fundic region contained less secretory granules. For the mucin histochemical study, the acid and neutral mucins can be found throughout the GI tract except for pyloric stomach found neutral mucin only. This study provides information about the microanatomic structures of V. salvator GI tract that could be applied to the biological and veterinary sciences, and farming and feeding management.