Refined Handling FAQs

A: Once staff and mice are adequately trained, husbandry tasks and experimental procedures typically do not take any longer than with tail handling. In fact, in a time study of four technicians, where tunnels were placed in the home cages two weeks earlier, tunnel handling mice for cage changes was found to be faster than tail handling with forceps on both the first and second cage changes (no training of the mice needed). For cup handling, typically some habituation for the mice is required initially so it may take longer initially.

In a survey on refined handling implementation, we found that the majority of respondents (<60%) report that cage change and handling time decreased, or stayed the same, after switching to refined handling. 

A: The benefits of refined handling persist even after standard or aversive procedures as long as the mouse is removed from the home enclosure via refined handling. These procedures include:

  • Scruff or tail restraint (Hurst & West 2010; Roughan & Sevenoaks 2018; Gouveia & Hurst 2019; Henderson et al., 2020)
  • Subcutaneous or intraperitoneal injection (Gouveia & Hurst, 2019; Henderson et al. 2020)
  • Anesthesia (Henderson et al. 2020)
  • Oral gavage (Nakamura & Suzuki, 2018)

A: Home cage tunnels are not necessary to gain benefits from tunnel handling. However, keeping tunnels in cages is beneficial as they provide enrichment, decrease training time as the mice are already familiar with the tunnel, and support biosecurity. If tunnels are not possible, cup handling is always a good alternative.

Note: to prevent cage leaks from home cage tunnels, be sure to place the tunnel away from the water valve and  parallel along the side of the cage as in the picture below (credit to the University of Washington).

A: Tunnels can be acquired from vendors such as Datesand, Braintree, LBS  Biotechnology, SerLab, Bio-Serv, etc. or from independent providers (e.g., Prices vary depending on the vendor and quantity, but can range from $4.00 – $10.00 (USD) each.

A: Tunnels should be appropriate for the size of the cage.

Not sure where to start? At some institutions, 3.5 inch square tunnels work well as they won’t become improperly wedged in the cages, and can provide an area for a breeding dam to pull up her pups in case of cage flooding.

If you already use cardboard tunnels those are a great alternative. However, if purchasing new tunnels, clear plastic is recommended. This is to allow for mouse visualization during health inspections and to easily slide the mouse out after they are picked up.

Tunnel handling has successfully been used in BSL2 and BSL3 laboratories and with immune-compromised mice (Doerning et al. 2019). Tunnels can be ordered in autoclavable material or purchased pre-irradiated to support biosecurity measures. See the Biosecurity section of the ‘Operations and Tunnels’ tab for more information.

A: Thus far, refined handling has been beneficial for all strains tested and both sexes (though males of some strains may take a bit longer to train). Strains tested thus far include BALB/c, CD1s, C57BL/6, DBA/2, and ICGN. These methods were also developed for handling wild-caught mice (Hurst & West 2010).

A: Refined handling methods have been shown to increase the reliability of behavioural data, by increasing exploratory behaviour and test performance (Gouveia & Hurst 2017). The stress of tail handling may be a research confound, and is thought to contribute to the failure to replicate behavioural experimental results, as animals are more anxious and cautious (Gouveia & Hurst 2017). Thus, refined handling may actually improve the accuracy and reliability of research data.

A: Generally, no. Best practice in experimental design recommends keeping all variables consistent throughout a study period. Therefore, we do not recommend switching handling techniques mid-study. It is possible it could confound your data. 

A: It is possible that your current or past research is measuring the stress response to tail handling, and not the variables or test articles that you are researching. You will be practicing better quality science once you remove extraneous variables from your research. Tunnel handling/cupping have actually been shown to improve performance in behavioural tests compared to tail handling (Gouveia & Hurst 2017).

For answers to more frequently asked questions check out the FAQ page on the NC3Rs website: