I’m not having much luck with the cow’s eye.  If you haven’t been following this, on Sili’s suggestion* I’m trying to find out what shape its pupil is.  It seems to be very like the horse’s eye, but I can’t seem to get good enough natural light to make the pupil distinct.  This cow got fed up with being chased by photographers, at least you can see that in her eye:

cow eye

* Danes have dairy genes.