Refinement and Reduction Value of Aspen Furniture and Restricted Feeding of Rats in Conventional Cages

This study evaluated the impact of aspen furniture on cardiovascular parameters, locomotor activity (LA) and faecal welfare indicators in rats. A total of 12 BN and 12 F344 male rats were group housed (n=3) in conventional cages. In this crossover study, responses of all rats to the following cage furniture items were investigated: two types of simple maze, a rectangular tube and a control with no cage furniture. In one of the two maze groups, the rats had to gnaw through wood in order to obtain food. The mean values of the LA in all groups and differences in mean arterial pressure (MAP) and heart rate of the rats housed in the various furniture item groups were compared to the values of the rats housed in control cages with no furniture, on days two, six, ten and 14 in each period (both light and dark phases). The F344 rats were generally more active than the BN rats during the dark phase, but not during the light phase. Based on the MAP results, the tube appeared to be a poor choice for F344 rats, while for BN rats all furniture items seemed beneficial, with both board types apparently superior to the tube. In general, F344 rats had higher faecal corticosterone levels than BN rats with the reverse being true for secretory IgA values. In conclusion, LA and cardiovascular parameters seemed appropriate ways to evaluate the impact of cage furniture on physiological parameters, and covered structures such as tubes do not seem to provide any enrichment value in these two rat strains