I've never heard of a law anywhere where it is your responsibilty to keep others animals out.
From earlier in the thread:
Fence laws by state https://nationalaglawcenter.org/state-compilations/fence-laws/
Yes, there are some states where it is your responsibility to keep animals OUT. Majority of US seems to be Fence IN your animals. Since we don't know where OP is from, who knows if they are in a fence IN or fence OUT state.