Threecats, you should look around in your area for low-cost spay options, call rescue groups and the humane society, see if they have any suggestions, they often have arrangements with sympathetic vets, save up your pennies, stagger the spayings over two or three months if that's what it takes. Did it occur to you that the fact that your cats are constantly on edge might be contributing to their negative relationship with your dog? Just a thought. But please do it, unspayed females are susceptible to serious diseases later on, which would probably cost you more in vet bills than what it would cost you to put them out of their misery now. Not to mention unwanted kittens if one of them should get out. Please!!
Someone from Threecats' area, weigh in here...any ideas?