I just discovered that the dog actually got me!
First picture is the dog cornered under my workbench.
I'm late to this ball game...but my husband works for the Health Dept in our state and is the person responsible for dealing with dog bites in the county. IN our state (your laws may be different), any dog bite that is reported to health officials (either your doctor or a hospital) MUST be reported to authorities by state law. At that point, the authority in that county MUST see vet records to show that the dog was PROPERLY vaccinated for rabies. If the owner CANNOT show vaccination records FROM A VET (many try to do it themselves), then they have two options - 1) dog must be quarantined by the state for 14 days at owner's expense OR 2) dog is put down, head chopped off and sent to a lab for rabies analysis.
Either way, these people can threaten all they want but the law is on YOUR side. Their animal came onto your property and threatened your livestock and yourselves. You are completely within your right to shoot it, hit it with a shovel, or do anything else to it that you choose. If they don't like it, they can pay the damages and keep their dog on their property.