Abstract:
Gavage is the most widely used method for precise oral dosing in experimental studies involving rodents. In the hands of a skilled operator, the procedure is rapid and allows for a precise volume (or dose) of a substance to be delivered directly to the stomach, where it can be absorbed. Gavage is advantageous in situations where the substance to be delivered cannot be incorporated into feed or is unpalatable. Of particular interest to the current readership is the common use of gavage in studies with a respiratory focus. Unfortunately, gavage requires conscious or lightly anesthetized experimental animals to be restrained, which is known to induce a stress response (increased plasma corticosterone levels) in both rats and mice. The procedure is also technically challenging, as esophageal trauma and aspiration, among other complications, can occur. Owing to the close proximity of the trachea relative to the esophagus, unwanted and nonspecific effects of gavage on respiratory function are likely and should be considered in experimental designs.
Confounding effects of gavage in mice: Impaired respiratory structure and function
It is therefore clear that gavage can have significant impacts on experimental animals in terms of their stress response and overall morbidity and mortality