The impact of light, noise, cage cleaning and in-house transport on welfare and stress of laboratory rats

Abstract

Human interaction and physical environmental factors are part of the stimuli presented to laboratory animals everyday, influencing their behaviour and physiology and contributing to their welfare. Certain environmental conditions and routine procedures in the animal facility might induce stress responses and when the animal is unable to maintain its homeostasis in the presence of a particular stressor, the animal's wellbeing is threatened. This review article summarizes several published studies on the impact of environmental factors such as light, noise, cage cleaning and in-house transport on welfare and stress of laboratory rats. The behaviour and physiological responses of laboratory rats to different environmental housing conditions and routine procedures are reviewed. Recommendations on the welfare of laboratory rats and refinements in experimental design are discussed and how these can influence and improve the quality of scientific data.

A guide to defining and implementing protocols for the welfare assessment of laboratory animals: eleventh report of the BVAAWF/FRAME/RSPCA/UFAW Joint Working Group on Refinement

“…Following cage cleaning in the rat, exploratory behaviours, shelter use, heart rate and blood pressure all increase significantly. 38 -41 Behavioural and physiological parameters can take up to 2 h to return to pre-cage change levels in rodents, 41 during which time these responses may mask important indicators and confound the welfare assessment. It may be advisable to conduct welfare assessment an hour or two after husbandry procedures such as cage change, as long as the potential severity of the procedure does not require more frequent monitoring.…”

Influence of Metabolic Cage on Wistar Rat Physiological State

“…Several authors have shown that cage cleaning promotes an acute stress response in laboratory animals (10,21). They reported that cage cleaning of adult male Sprague-Dawley rats, housed in groups of three, elevated serum concentrations of corticosterone and prolactin (15,22,23). We found that daily cleaning of metabolic cages and urine samples taking caused fear in rats.…”

Essential Requirements for Resorbable Bioceramic Development: Research, Manufacturing, and Preclinical Studies

“…Light through its intensity, color, and photoperiod influences animal behavior (e.g., aggression and cannibalism in rodents), body weight, reproduction, etc. [70]. Any changes to these environmental parameters can cause physiological disturbances in the animals that can alter the results of a study or increase the variability of the results, making them difficult or impossible to interpret.…”