2004

Fluctuating asymmetry in relation to single housing versus group housing in three inbred mouse strains

Stub, C., Ritskes-Hoitinga, M., Olsen, A.K., Krohn, T.C., Hansen, A.K.
Scandinavian Journal of Laboratory Animal Science, 31 (4), pp. 245-249, 2004
Abstract:
Fluctuating asymmetry (FA) reflects small, random deviations from symmetry in otherwise bilaterally symmetrical characters and has been used to detect harmful conditions such as environmental and genomic stress in growing animals and humans. The development of FA may be related to the balance between canalization (the ability of the genotype to develop a constant phenotype under changing environments) and plasticity (the ability of the genotype to change phenotype dependent on the environment) of the individual. Different mouse strains differ in coping strategies in stress situations, and these coping strategies may be related to this balance. In this study, development of FA was studied in female mice of three different inbred strains, 129s6/Sv, C57BL/6J, and BALB/c, during a 6 week period. Besides the comparison of different strains, single housing was compared to group housing conditions. Overall, FA did not differ between strains. After six weeks, single-housed mice had higher FA than those that were group housed (P<0.001), which may indicate that single housing causes a higher degree of environmental stress than group housing does.

 

Rearing and caring for a future xenograft donor pig
Hansen, A.K., Dahl, K., Sorensen, D.B.
Acta Veterinaria Scandinavia, Suppl. 99, pp. 45-50, 2004 

 

Reduction in the spread of rodent urinary allergens during cage changing by Laminar Air Flow cabins
Krohn, T.C., Hansen, A.K.

Scandinavian Journal of Laboratory Animal Science, 31, pp. 149-154, 2004

Abstract:
As spread of allergens, especially during handling and cage changes, is a problem in the animal facility, initiatives are taken to reduce this spread. The aim of the present study was to evaluate the effectiveness of a LAF-cabin (Laminar Air Flow cabin), and its ability to protect the staff against inhaling allergens during cage changing of rats, and mice. The allergens were sampled from the handler's breathing zone and from different places inside the cabin. Subsequently the amount of allergens was quantified by an ELISA testing for Mus m1 and Rat n1.

The use of the LAF-cabin reduced the amount of rat and mouse allergens in the breathing zone by at least 90-95%. The study shows that by using a LAF-cabin for cage changing it is possible both to achieve an essential reduction in allergen exposure for the cage changing staff and at the same time keep the allergens inside the ventilated area of the cabin, thereby preventing allergen contamination of the surrounding facilities. The potential advantages compared with other techniques are outlined.

 

Consequences of enhancing environmental complexity for laboratory rodents - a review with emphasis on the rat
Sorensen, D.B., Ottesen, J.L., Hansen, A.K.
Animal Welfare, 13, pp. 193-204, 2004
Abstract:
Enhancing the complexity of the environments of captive animals is often referred to as environmental enrichment and aims to have positive effects on the animals' well-being. Such enrichments may have consequences both for so-called 'normal' behaviour and for the pathophysiology of the animals in question. The effects of a lack of environmental complexity, including social isolation, on home cage behaviour and on pathophysiology in rats is considered in this review. Several preference tests on rats - choice tests and operant tests - indicate a preference for bedding, nesting material and social contact. Contradictory research results concerning the need for gnawing objects per se are more difficult to interpret and it is argued that excessive gnawing may be indicative of primary frustration and hence reduced welfare. One disadvantage of providing environmental enrichment to laboratory animals is a possible increase in subject variability, resulting in the need to use a greater number of test animals. However, this increased variability seems to be inconsistent and is not very well documented It is argued that in cases where the behavioural benefits of environmental enrichment justify the use of more animals, better welfare should be more highly valued than a reduction in the number of animals used.