The impact of housing conditions on the behavior of laboratory animals (#558)
Many scientific studies are focused on animal behavior. Standardized tests are used for greater comparability. But often, housing management aspects and their impact on the animal’s behavior are underestimated. We analyzed pigeons and chickens in standardized test, the open-field, the x-maze and y-maze, under different feeding practices (feed restriction, rationed feeding, ad-libitum feeding). Additionally, chickens were housed in groups or isolated and tested with respect to their discrimination abilities in an operant conditioning chamber. Motivation effects of food restriction were found in both species, but were greater in pigeons. In the open-field, pigeons which were food restricted showed a higher exploration (p=.002). Whereas chickens were not influenced by feeding conditions (p=.175). In the x-maze, learning criterion was reached by all chickens (p=.157), but only by food restricted pigeons (p≤.001). In the y-maze, chickens choose food more often when food restricted (p≤.001), whereas conspecifics and humans were chosen equally under other food conditions (p=.723). Pigeons avoided humans independently from feeding conditions (p=.002). Chickens which were housed isolated showed a higher pecking rate than chickens housed in groups (p=.002).The results show that housing conditions have an impact on the animal’s behavior. Therefore, we found hunger to be major drive of specific behavioral traits. Explorative behavior might be driven by the animals need to search for food. Isolated housing conditions affect basic social components in terms of pecking behavior which we explain by the lack of interspecific contact. In general, species were affected by housing conditions differently with pigeons being more stressed under food restriction and showing higher motivational than chickens. At the same time, pigeons show a higher level of avoidance of humans which requires a higher motivation. This study shows the importance of not only standardized tests but also standardized housing conditions which fit the animal’s species-specific needs.