* Nesting behavior. Rats will start building a nest out of bedding material in preparation for giving birth. The nest will usually be located in a dark, secluded place.
* Increased thirst and urination. Rats will drink and urinate more frequently in the days leading up to labor.
* Relaxed or restless behavior. Some rats may become more relaxed and inactive, while others may become restless and active.
* Swollen abdomen. The abdomen of a pregnant rat will be noticeably swollen.
* Weight gain. Rats will gain weight in the weeks leading up to labor.
* Change in appetite. Some rats may eat less in the days leading up to labor, while others may eat more.
* Vaginal discharge. Rats may have a clear or slightly bloody vaginal discharge in the days leading up to labor.
If you observe any of these signs, it is important to prepare the nesting box and ensure that your rat has access to plenty of fresh water and food. You should also avoid handling your rat too much during this time, as it may cause stress.