I get it NOW! Its like they painted cocks and/or balls ONTO the cows only they used bleach on dark areas of the cows to make the drawings more permanent.
Marking cows with bleach is a know practice to mark which cattle are headed to market.
See article at link below.
https://www.dtnpf.com/agriculture/web/ag/news/article/2022/10/24/marking-cull-cows-bleach-costing
know = known