Ad libitum Diet Mouse (IMAGE) Cell Press Caption This photograph shows a mouse on an ad libitum diet, meaning it could choose when and how much to eat. Credit Maria Fernanda Forni Usage Restrictions Credit Required. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.