Provision of food and water in rodent whole body plethysmography safety pharmacology respiratory studies - Impact on animal welfare and data quality

IntroductionWe evaluated the feasibility of providing food and water to rodents during whole body plethysmography (WBP) studies as a welfare improvement to standard conditions.MethodsMale Han Wistar rats or CD1 mice (n = 8) were placed in WBP chambers and respiratory parameters recorded for approximately 6 h on four separate occasions. On each occasion the animals were exposed to a different plethysmography chamber environment using a randomised design: no food/water (the standard conditions), water bottle, hydrating gel and wet food. In a further session, rats (n = 8) were administered theophylline, or vehicle and respiratory parameters measured in the plethysmography chamber containing wet food.ResultsRespiratory parameters of rats were not significantly altered by the provision of water or food. Providing wet food resulted in reduced body weight loss. Administration of theophylline caused the expected increase in respiratory rate. When mice were given access to hydrating gel or wet food the respiratory parameters were significantly affected; respiratory rate and tidal volume were increased. Providing wet food resulted in reduced bodyweight loss.DiscussionThe provision of food and water did not impact on respiratory parameters in rats placed in WBP chambers. When provided with wet food, rats lost less bodyweight. Therefore, to improve welfare conditions for rats during WBP respiratory studies wet food should be provided when appropriate to the study design. In mice, provision of food and water led to changes in respiratory parameters, therefore these improvements in welfare conditions are not suitable for mice.