A rating scale for wildness and ease of handling laboratory mice: results for 21 inbred strains tested in two laboratories

Abstract

Rating scales for difficulty in capturing and holding mice were devised that proved to be easy to use and highly sensitive to differences among mouse strains on the A and B priority lists of the Mouse Phenome Project. The simplicity of the scales makes it feasible to rate wildness during behavioral test sessions without adding much to testing time or distracting the technician from the principal task at hand. Overall wildness and placidity ratings obtained by combining capture and hold ratings provide a good impression of the difficulties encountered while working with lab mice in the course of complex experiments. Ratings of 21 inbred strains during the course of 15 behavioral tests in two laboratories demonstrated that the SPRET/Ei, PERA/Ei, CAST/Ei and SWR/J strains were particularly difficult to handle. The NOD/LtJ strain posed no special challenge in the Edmonton laboratory but was very difficult to handle in the Portland lab. The rating scales should be useful for judging the difficulties in working with novel targeted or induced mutations in mice as well as effects of a variety of environmental treatments or drugs.

Social approach and repetitive behavior in eleven inbred mouse strains

“…Crabbe, Wahlsten, and colleagues [12,47,49,50] have provided compelling evidence that results from behavioral testing can significantly differ between laboratories, even when procedures, animal source, and other environmental factors are carefully controlled and standardized. Discrepancy of findings may be greater in tests related to anxiety-like behavior [47].…”

Long-term effects of cage-cleaning frequency and bedding type on laboratory rat health, welfare, and handleability: a cross-laboratory study

“…Strain differences are commonly acknowledged to affect many biological variables; for example, searching the Institute of Scientific Information (ISI) Web of Science for the terms 'strain differences' and 'rats' revealed 725 records. In contrast, extensive searching for animal unit differences yielded just two meta-analyses (Haseman & Rao 1992, Kafkafi et al 2003 and seven crosslaboratory experiments (Lee & McClintock 1986, Crabbe et al 1999, Salome et al 2002, Masaya et al 2003, Wahlsten et al 2003a,b, Wolfer et al 2004. All of these studies, except one (Wolfer et al 2004), found important inter-laboratory effects.…”

Mouse Models of Neurodegenerative Diseases: Criteria and General Methodology

“…The main question asked during such characterisation relates to the abilities of a mouse genome to cope with the presence of an expressed transgene protein. The existence of possible effects due to strain genetic background, modifier genes, compensatory effects, and/or subtle differences in the experimental paradigms, including the strains' different response to handling (133), can yield different, often contradictory results. Therefore, a broad characterization of mouse behaviour, including both hippocampus-independent memory systems (134)(135)(136) and other non-cognitive behavioural systems, such as changes in agitation and aggression levels (137), locomotor, exploratory, or stereotypic activity (138) can be very useful in evaluating transgenic mice.…”