German Shepherds will go into estrus for the first time when they are 6 to 8 months old. However, due to various reasons, some dogs may go into estrus later or earlier. As long as they go into estrus before 1 and a half years old, it is considered normal. However, breeding is not recommended for the first time of estrus. At this time, the dog is not fully developed, and it is easy to have dystocia or the puppies are born in poor health. In addition, female dogs are in estrus only twice a year, but as long as there is an estrus female dog near a male dog, she will also start to go into estrus.

Things to note when a German Shepherd is in heat:

1. When a female dog is in heat, walk her dog at peak times and in crowded places to avoid being chased by male dogs.

2. Female dogs will bleed when they are in estrus, and owners need to pay attention to cleaning their dogs in time to avoid infection.

3. During estrus, the dog should be given nutrition supplements and food that is nutritious, palatable, and easy to digest.

4. Keep the dog warm during the period of heat and do not let the dog catch a cold.