Material can be administered orally using a number of different techniques, although gavage using a stomach tube is the most widely used. To minimise the risk of adverse effects associated with this procedure, it is important that the operator is skilled both in the technique and the restraint method needed.
Although gavage can be undertaken using rigid dosing cannulae, flexible catheters or tubes are preferred, and these are less likely to cause oesophageal trauma. Inadvertent dosing into the lung may occur, and this usually results in the animal showing immediate signs of respiratory distress. If this is observed, then the animal should be humanely killed.
As an alternative to gavage, some materials may be consumed voluntarily in palatable mixtures (e.g. flavoured gelatine) (Zhang, 2011*) (Küster, Zumkehr, Hermann, Theurillat, Thormann, Gottstein, Hemphill, 2012**). Material can also be dosed using a small flexible catheter introduced only into the animal’s mouth.
When possible, these approaches are to be preferred to dosing using a stomach tube, since they are not associated with complications, such as tracheal dosing or oesophageal rupture.
**Voluntary Ingestion of Antiparasitic Drugs Emulsified in Honey Represents an Alternative to Gavage in Mice, Authors: Küster, Tatiana; Zumkehr, Beatrice; Hermann, Corina; Theurillat, Regula; Thormann, Wolfgang; Gottstein, Bruno; Hemphill, Andrew, Source: Journal of the American Association for Laboratory Animal Science, Volume 51, Number 2, March 2012 , pp. 219-223(5) Publisher: American Association for Laboratory Animal Science