Is it abnormal for puppies not to open their eyes by 16 days old?

Puppies are usually born with their eyes closed and typically open them within 10-16 days. While it is not uncommon for some puppies to open their eyes a few days later than this, it is considered abnormal if a puppy has not opened its eyes by 16 days old. If your puppy has not opened its eyes by this age, it is important to take them to a veterinarian for an evaluation. The veterinarian can check for any underlying medical conditions that may be preventing the puppy from opening its eyes and recommend appropriate treatment.