NAVLE（北美执业兽医考题）Day 422

An owner brings her 4-year old female Labrador Retriever to your clinic because she believes she might be pregnant. She does not remember when the dog's last heat cycle was. The dog's abdomen appears fairly distended and you take a lateral abdominal radiograph which is shown below. What would be the earliest time you would expect to be able to see fetal skeletons on abdominal radiographs in the dog?