The distance measured from the tip of the nose to the earlobe and from the earlobe to the xiphoid process
Inserting NGT can gain access to the stomach and its content. Draining of stomach content is possible, decompression or obtain a specimen of the gastric content is possible. This can allow gastric immobility and gastric obstruction to be identified. This is usually contraindicted to patients with facial trauma due to possibility of inserting the tube intracranially. Complications that can be expected are aspiration, trauma.
Because nowadays, many horses are domesticated, and food they would have eaten in the wild, they don't usually eat anymore. They have learnt to adapt to eating other foods, like hay, that require molars to ingest. This is why over time, their tooth structure has changed.