If dogs without moleras are found to be acceptable when it comes to the current breed standard, there's no good reason for dogs to be born with large, gaping skull holes that never close. (littledogtips.com)
Boston Huahua puppies are born with a skeletal condition called molera which is an open gap at the top of their skull that closes as they grow into adulthood. (petguide.com)
This can include excessively large moleras (the natural open spot on the Chihuahua's skull) and eye problems. (dogs.lovetoknow.com)