Identification and clinical examination of jaundiced rats

Rats with or without spontaneously occurring jaundice were clinically examined. Jaundiced rats had five-fold higher serum bilirubin concentrations than control animals. About 90% of serum bilirubin in the jaundiced animals was in conjugated form. Control and jaundiced rats did not differ with respect to clinical signs such as alertness, stance, hair coat, position of eyes, discharge from eyes and nose, and cleanliness of anal orifice. While examined individually, jaundiced rats could not be identified readily on the basis of a yellow colour of sole of feet, nose, ears and tail. When kept together with control rats, jaundiced rats could be selected reasonably well. Urines of jaundiced rats had a more intense yellow colour than urines of control animals. Rats with jaundice were significantly more active in a small open field test than control rats.