Solitary Caging Protects Mice from Ankylosing Enthesopathy

Abstract

Murine ankylosing enthesopathy (ANKENT) is a spontaneous joint disease with numerous parallels to the human seronegative spondylarthropathies at the level of disease distribution, genetics and pathology. Although several genetic susceptibility factors have been identified previously, there is variation in disease susceptibility among genetically identical individuals, living in a stable environment. Preliminary observations indicate that males housed together with females rarely develop the disease, in contrast to males housed with other males (p < 0.25, p < 0.05, and p < 0.01). Furthermore, males caged under solitary conditions developed no ANKENT, whereas the disease did develop among individuals housed in groups of 4 (p < 0.01). The mechanism through which grouped caging induces a risk for ANKENT requires further study.

Sex preference of ankylosis in collagen‐induced arthritis in B10.RIII mice

“…The gene responsible for spontaneous ankylosis in C57BL10 mice is reported to be a class I gene 14 . In addition to genes, environmental factors seem to be critical in the development of ankylosis, since the condition of the mice's cages affected the incidence of ankylosis 15 . Furthermore, germ‐free mice did not develop ankylosis 16 .…”

Recommended housing conditions and test procedures can interact to obscure a significant experimental effect

“…Toward this end, laboratory animal veterinarians and care providers properly make many suggestions that may improve the health status of the animals (see, e.g., Olsson & Dahlborn, 2002;Porter, Scott, & Walker, 1970). Among the recommendations commonly made are for group-or at least, pair-housing (e.g., Love, 1994;Simmel & Walker, 1972), with the assumption that this yields a healthier animal, although the data are in fact mixed (e.g., Rao & Lindsey, 1988;Weinreich, Hoebe-Hewryk, Boog, & Ivanyi, 1996). We received just such guidance to house our animals in pairs, guidance which we heeded.…”