"The Behavioral Effects of Environmental Enrichment in Rats"

Abstract

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The Effects of Environmental Conditions on Activity, Feeding, and Body Weight in Male and Female Adolescent Rats

“…Similar studies in the research literature, which reported statistically significant effects, had cell sizes of 7 -12 animals for enrichment (e.g., Van Praag et al, 1999;Elliott & Grunberg, 2005;Tomchesson, 2004). Mering Kaliste-Korhonen and Nevalainen (2000) determined that 5 -10 animals were needed to find statistically significant effects for enrichment on various biological measures including body weight and fat/adipose tissue.…”

“…In addition, a variety of objects (durable toys including colored textured balls, rings, and bones) were placed in the cage to provide physical and tactile stimulation. This particular enriched environment has been effective in previous experiments in our laboratory assessing environmental effects on performance and activity (Elliott, 2004;Tomchesson, 2004 (Sclafani & Springer, 1976;Bowling, Rowlett, & Bardo, 1993;Hellemens et al, 2004 …”

“…Environmental enrichment has been reported to decrease body weight in adult rats (Sclafani & Springer, 1976) and adolescent rats (Hellemens, Benge, & Olmstead, 2004;Tomchesson, 2004 Regardless of their housing condition, animals provided with a "cafeteria diet" (cookies, potato chips, salami, marshmallows, etc.) gained more weight than did the rats that were provided standard chow.…”

“…In an experiment examining the behavioral effects of environmental enrichment, 21-day-old male Sprague-Dawley rats were fed standard chow during a 4-week enrichment period. Animals in the environmental enrichment condition ate less than did animals in the non-enrichment condition (Tomchesson, 2004). In this experiment, food consumption was used to monitor animal health and was not the primary focus of the research project.…”

“…The standard non-enriched environment limits the physical and social enrichment by housing the animals individually without objects (Varty, Paulus, Braff, & Geyer, 2000). Most current environmental enrichment studies include both social and physical enrichment components (e.g., Pham et al, 1999;Passineau, Green, & Detrich, 2001;Tomchesson, 2004).…”