Hello @Sarah4275 from across the oceans and lands in Auckland, New Zealand
Great listing you have.
Have you browsed through Experiences to see what other similar situations where animals are would charge?
There's also some discussions here in CC in respect of liability should their be accidents or injuries which one will need to factor into account.
Maybe create some signs like they have in Public Parks/ Domains where livestock are and how it's animals territory and risks are the responsibility of the visitors.
What breed of cows/ bulls are the black and white cattle in your listing?