Periodic stays in a 'playcage' as an environmental enrichment measure for laboratory rats housed in individually ventilated cages: Short report.

Male Zucker Diabetic Sprague Dawley rats were housed in standard individually ventilated cages with floor area of 1500 cm 2 , and were placed in a 'playcage' (a large open cage) for three visits per week from the age of 16-18 weeks. The playcage was introduced in an attempt to reverse the compulsive behaviour that the rats displayed in the individually ventilated cages, with the purpose to increase their well-being and to provide cognitive as well as physical stimulation. After two weeks of periodic stays in the playcage, the rats' repetitive behaviour in their home cage ceased, and the rats displayed signs of happiness and excitement when they were in the playcage. The observations strongly indicate that periodic stays in a larger playcage can be an alternative environmental enrichment for laboratory rats when housing in a larger home cage is not an option.