outspoken said:
I was told once, that dogs and cats are the only animals which can deliver twins from different sires.
Does your PB Angus bull- carry the red gene?
On 2nd thought- are you sure they are both hers?
I think you were told wrong.
Humans can, I used to have mixed litters of bunnies when I was a kid, I see now reason why it could not happen in a cow. ESP if one or both were before the egg dropped, since cows typically stand before the egg is dropped I see it as very plausible.
At fertilization, there is a small micro current release, at least in humans that acts to kill other nearby sperm, this acts to prevent two sperm from entering the egg. In most cases maternal twins each egg comes from each of the two ovaries, therefore I would assume the eggs would be far enough up in the horn of the cows uterus that the micro current from one egg being fertilized would not effect the sperm and egg in the other......
Just reasoning from one species to another which is not always accurate but serves as a solid enough basis to justify animal experiments for human products.