Actually, that IS the point.
Bovine excement doesn't contain the listeria bacteria.
Human excrement might.
And you are correct. No kind of excrement belongs on food.
In the soil, yes. On the food, no.
/johnny
Google is your friend. Try “listeria and cows” as a search.
20 listings that say cows carry listeria bacteria couldnt all be wrong even if it is the internet.