If the goal is to kill the pests then why would it matter if the method was via bull terriers or poison? If the poison is contained in two places, the bait box and rodents mouth then it's not going where it's unwanted therefore no unwanted casualties. Yet a dog can harm me, my chickens and my cat. Like I'd stated earlier; in well over a year of use only once was a rodent (chipmunk) dead on the ground, the rest die in holes and nests away from animals who'd eat them.
Rats are prolific. Able to reproduce at 3-4 months of age. Have a liter of 6-14 pups in 21 days. Go into heat every 5 to 6 days. It gets ugly quick. Even uglier if some decide to winter over in your house to brood another 10 pups each in your walls and attic. If you take care of it then your house will stink. Best to nip this type of problem early and hard. If it gets out of hand in a barn situation they eat eggs and young poultry.
Rats are prolific. Able to reproduce at 3-4 months of age. Have a liter of 6-14 pups in 21 days. Go into heat every 5 to 6 days. It gets ugly quick. Even uglier if some decide to winter over in your house to brood another 10 pups each in your walls and attic. If you take care of it then your house will stink. Best to nip this type of problem early and hard. If it gets out of hand in a barn situation they eat eggs and young poultry.