Three strong possibilities.....and one Sneaky Tana.
. If I were to bet, I'd place my money on the longshot. Your "I'm not pregnant at 0800, but at 1300 look what I have" photo is plenty enough proof for me! ROFL
Do mares have silent heats like some bitches do? When I was in show dogs, we had a Soft-Coated Wheaten Terrier that didn't want to come off the truck to go to the exercise pen. As we stood back to the end of the leash and knelt down to encourage her. Imagine our shock when, as she squatted to "pee"....she delivered a pup instead!!
Having a pregnant bitch on the show grounds is very highly frowned upon.) She delivered a litter of strong, healthy brindle puppies...thereby giving away the father. It was the brindle and white Best in Show winning Whippet she was usually turned out with at home.
Our head handler got called in by the show committed and actually received a suspension of 2 shows. That would have kept him from handling client dogs at several Specialty shows and left us with some very angry clients.
Fortunately, the owner had vet records showing that her dog had silent seasons. She also admitted that she "forgot" to inform us because she was so excited to send her dog on this particular show circuit. It was where she would have, most likely, earned her last 3 point major to finish her championship.