I turned this male rate into a female rat.

Studies have been done in the past on normal, mature and castrate female rats.

It was a huge, sleek fat female rat, already pregnant by the looks of things.

All female rats in the study displayed this behaviour, while 30% of the males did not.

Experiment 3 In this study, male and female rats were examined together.

The most sensitive is liver cancer in female rats, and this has long been a basis for risk assessment.

It is reported to have contraceptive activity when given to female rats 1-5 days after coitus.

He then put the rat in a cage together with ten female rats.

Then he took a third female rat, and a fourth, and a fifth.