LABFEED

Today laboratory rodents are almost always fed ad libitum, even though this has negative health and welfare implications as compared to restricted feeding. Ad libitum feeding of rodents is probably still practiced for practical and economical reasons. By using food restriction schedules, the health and welfare of the animals is improved, which also increases the quality of the results... Group housing contributes to the variability in food consumption and related parameters, under ad libitum feeding conditions. The dominant animals will ingest more than the subordinates, thereby receiving more food and agents mixed in the diet (Ritskes-Hoitinga and Strubbe, 2004). In inhalation studies, variability in body weight at 12 months accounted for up to 85 % of the variability in liver tumor incidence in male mice and up to 70 % in female mice (Roe 1994). Variability in body weight is the result of different food intakes.