Bartlett, J., Davies, J., Purawijaya, D. et al. 2022. Refinement of handling and dosing methods for rats and mice. Animal Technology and Welfare 21(2), 120-124.

Modified Handling for Mice: Handling mice by gripping the base of the tail has been shown to negatively impact animal welfare by increasing anxiety and aversion to handling. We aimed to refi ne the dosing procedure by finding a handling method that allows the same level of control over the animal without gripping the base of the tail. Mice were restrained for intraperitoneal dosing using either a conventional method using the tail or a novel method illustrated in Figure 1. Preliminary studies quantifying overt signs of stress in mice suggest this modified method is associated with better welfare. Aversion on release from restraint was significantly reduced and all other measures except vocalisation were lower for animals in the modified method group. Restraint-Free Oral Dosing: Conventional methods of oral dosing require the animal to be restrained and the insertion of an oesophageal cannula. Restraint of the animal causes stress and the insertion of a cannula carries a risk of injury. Voluntary ingestion of drugs in palatable solutions enables restraint-free oral dosing of rats and mice. This refinement not only reduces the stress caused to the animal during the dosing procedure but also eliminates the potential risks associated with oral gavage dosing. Once the animals are happy drinking from the syringes, this method can in fact save time as one person can easily dose two animals at the same time. Modified Handling for Rats: All members of our laboratory are taught to restrain and dose rats without having to use the standard scruffing or two-person restraint (Procedures with Care) method. For intraperitoneal (I.P.) injections, the rat is held around the shoulders and gently pushed down against the handler’s chest, stomach or side. In this position the stomach is relaxed making I.P. injections less aversive and the rat is being controlled without it becoming agitated. All members of our laboratory are taught to restrain and dose rats without having to use the standard scruffing or two-person restraint (Procedures with Care) method. For intraperitoneal (I.P.) injections, the rat is held around the shoulders and gently pushed down against the handler’s chest, stomach or side. In this position the stomach is relaxed making I.P. injections less aversive and the rat is being controlled without it becoming agitated.