It's sad that irresponsible owners let their dogs roam to attack wildlife. The sheriff's office here will send a deputy out to warn the owner once. State law provides protection for the lifestock owner here... so if you call twice the response is often..."You own a gun and a shovel?"
Last year a small mixed pack ran across our property and killed eight of the wife's Heritage Breed chickens for fun. They sell for anywhere from $25 to $75 each.
Of course lambs and calves are much more expensive to replace. 
Good luck with the new pump. I went with the .357 Big Boy Carbine with Skinner sights.
