Distinguishing between rat and mouse droppings can help with identification. Brown rat droppings are dark brown and tapered at the ends, while black rat droppings are curved. Mouse droppings are ...

A two-year-old male pet mouse (Fig. 1) and a two-year-old female pet rat (Fig. 2), both diagnosed previously with neoplasia, were presented by different owners. The mouse was kept in a group of ...