For all our pets & those we foster (feral strays we tame enough to get to the Vet for spaying/neutering, shots, etc.), we use Nature's Way Black-Walnut
Hulls caps (least expensive, in green & white containers) opened up, sprinkled into & mixed well with their moist food. To a large can of people-quality tuna fish, we mix 2-3 caps of BWH, adding raw oats or cooked rice for extra nutrition (don't pour off the "juice" since you can "stretch" it this way). After their first "treatment", we saw worms, but never since (tho' we use it a few times per week for maintenance). The dose is what they'll tolerate in the tuna & they have no trouble gobbling it up. If we use more, however, they're balkish about eating it quickly. So you'll have to tailor the dose to your individual pet(s), always making sure they have plenty of fresh water.
Our babies are beautiful, bright-eyed with shiny coats, very energetic, & don't need subsequent trips to the Vet after their initial visit. A friend with close ties to vets informed me that pet vaccines are actually effective for up to 5 years or more ... meaning that we don't all need to be so OCD about these, as long as they get what's required by law (annual rabies shot). I've even read that all the shots they get each year can be toxic to their systems (not to mention all the poisons used for deworming, etc, tho' i'd rather have them free of fleas & pests than scratching themselves to death ... Brewer's Yeast in their food helps with that).