Their waste is made up of grass and hay
Remove fibrous waste, toxin and mucus from their bodies
All living things need to rid their bodies of waste materials
yes it is yellow and sticky and not very nice on your hand
Any/all animals that ingest nutrients must excrete the undigestible residue. Cows are no different than any other animal. They produce "pasture patties".
yes they do. if you dont beleve me got to a nature scince center
Grass contains carotenoids, which makes the fat, milk, cream, and butter from grass-fed cows yellow. Fat from cows fed indoors, on grain or grain-based pellets, is white.
No one knows the answer to that except scientists. I think that they aren't yellow because nature wanted them to be black and white.
You just defecate.
Yes, snails defecate
No, not at all. There are mustard-coloured cows, but they're not really called mustard-coloured, but rather yellow, dun or buckskin.
When they eat food, they have to defecate. They would also defecate if they have intestinal problems or sickness. Also, fear and stress can make animals defecate.
Cows aren't very trainable, except to come in for feed and go out to pasture. So it would be unlikely to train a cow to use a human toilet. Besides, they'd likely crack the porcelain because of their adult weight. In any event, they urinate and defecate in pastures and barns.