Comfortable Quarters for Rabbits in Research Institutions

In the past, laboratory rabbits have usually been kept singly in small cages that provide neither social nor environmental enrichment, and frequently the cages have been too small to permit some normal behaviors such as sitting up on the hind legs, hopping, digging, and hiding. Stereotypical bar licking or chewing, pawing at the corners of the cage, psychogenic polydipsia, and excessive self-grooming resulting in the development of trichobezoars are frequently seen in such animals and are recognized as indicators of reduced well-being. Single-caged rabbits often look unhealthy and depressed, sitting in a hunched position for hours on end. The extreme boredom induces some animals to overeat, others to undereat, leading to obesity and severe weight loss, respectively (Gunn-Dore, 1997). In addition, there are serious clinical problems associated with the small cage. Degenerative changes of the lumbar spine and femoral head have been attributed to the lack of basic locomotor activity in the small, conventional cages (Wieser, 1986). It is questionable if statistically reliable and scientifically meaningful research data can be obtained from animals kept under such inadequate housing conditions.