Dietary and Water Restriction

Dietary and Water Restriction

Approved January 21, 1999    (Download) 

Background: Behavioral research often requires that an animal perform a task for which it receives a food or fluid reward. This situation is not unlike conditions in the wild, in which animals must forage, travel distances, solve problems, or otherwise work to obtain food and water. Performing a task for rewards may also be behaviorally enriching for laboratory animals, especially nonhuman primates. However, a fundamental concern with studies that may involve food or water deprivation is that animals are maintained in a healthy state and that they not experience pain or distress.


Policy: Whenever an animal obtains any portion of its diet through food or water reward, the sum of the food and water earned through reward and of the food and water provided “free” (without the necessity of earning it) must be sufficient to maintain the animal in a healthy state without a loss of weight, unless approved by the ACC. Whenever possible, the reward should be a “treat” which is sufficiently desirable and motivating for the animal that dietary or water restriction is unnecessary.

Dietary or water restriction must be scientifically justified and approved by the ACC. If an animal loses 20% of its pre-study body weight, food and water intake must be increased immediately until the weight is regained. In research protocols submitted for ACC review, investigators working with young, developing animals should specifically address the need for dietary requirements for normal growth.

When food or water is not provided ad libitum, either the animal should be permitted to earn feed and fluids to satiety during the period of behavioral training or its intake should be appropriately supplemented on a daily basis. In cases where supplements are required, the amount of feed and fluids to be provided daily should be equivalent to the amount typically consumed by the animal when it is provided with feed and water ad libitum. An exception to this policy will be made for the day immediately following a 24 hour or longer period in which the animal is provided with feed and water ad libitum. On such days a reduced supplement is permitted if the normal supplement is demonstrated to interfere with behavioral training.

The type (e.g., water, fruit juice) and concentration, if applicable, of the feed and fluid reward must be specified in the ACC protocol. Weekly weight records and daily records of intake must be maintained and be available for review by veterinary services and the ACC. Each animal under food or fluid restriction must be observed at least daily by trained and experienced investigative staff.