There’s a VERY good chance it is, in fact, allergies…the question is whether this is environmental or related to food.
So, here’s an easy thing to rule out: what does your dog eat? If a dry kibble, what brand and formulation? Chances are you need to pick up a higher quality food with a novel protein. I would try something with zero corn or other grains and a protein source that *isn’t* chicken or beef. Ideally the food will have meat as the first three ingredients.
While you’re working on a food change, wash your dog’s paws every time she comes inside from the yard. Give them a good rinse with apple cider vinegar, too.
Finally: involve the vet. Depending on the severity of the reaction, your dog may very well need meds to get past this initial itchy spot.
Because I am a stickler for accuracy in language: If they’re a mix, then they aren’t purebred. The word “purebred” means an animal bred from parents of the same breed or variety. Because you have two different breeds involved, they are a mix.
That said…do they go outside? Have you taken a fecal sample to the vet annually? I give heartworm preventative 4x a year – my old man cat doesn’t go outside, and I get annual fecal and blood testing done for him. Get fecals and blood panels done, at the very least, to make sure everything’s good. Without a full picture of your cats’ health, you cannot make an educated decision on how to handle medications and the like.
I’m really sorry for the mistake, so they’re not purebred (my cousin told me that that’s how purebred cats are and I believed him), anyways, I’m not an expert in cats nor am I accurate in language. My cats go indoors and outdoors whenever they want and I’ve never taken them to any fecal or blood tests but I do have a vet coming to my house every month for a checkup on my cats’ overall health.
If they go outside, then yes, they should be on heartworm preventative. I would also have them on an external parasite preventative/flea and tick preventative, as well.
Have they ever seen a vet? Vaccines? If not and they are outside then you have more to worry about then worms. You need to get them checked out properly by a vet and you need to consider them to be indoor cats. Outdoors cats have a short life so and of around 5 years or less. I door cats can live up to 20. You say they have been sick before, most likely because they caught something outside. I would take to a vet and let them administer the medicines and preventatives. It’s not that much money to have this done.
Thank you for the answers