The abstract noun "undesirableness" can be translated with an adjective. AT: "such ugly cows" or "such worthless looking cows" (See: [[rc://en/ta/man/translate/figs-abstractnouns]])
This can be stated in active form. AT: "no one would have been able to tell that the thin cows had eaten the fat cows" (See: [[rc://en/ta/man/translate/figs-activepassive]])