Dog Heartworm Treatment

Can someone please advise me what can cause hair loss over most of the lower portion of the cat’s body…basically from the neck down, and sores that resemble mosquito bites? He is healthy otherwise. Good color, good eating habits, gets good food, playful, and his stools are fine. He doesn’t have worms either.
Yes, he’s been “vetted” and I fear that’s how we wound up in this mess. I had this previously healthy cat neutered, and since three days afterward he’s been in THIS condition. Three vets later now, $1600, they’re still telling me it’s a flea allergy. I DON’T HAVE FLEAS!!! I have seven cats. I have taken ALL of them to these three vets. One of said cats even has a documented history of flea allergy, yet she shows NO symptoms of hair loss. Now I’m broke and he’s STILL almost naked. I use Revolution on the dogs. Frontline on the cats, and my house AND my entire yard are treated faithfully because of my older cat’s flea allergy. Way back when, she went bald…no sores, just bald. Since then we’ve had no flea’s.
Can someone give me ANY ideas? I believe I now have what appears to be cat number two coming down with same symptoms. They’ve had skin tests and the whole nine yards…NOTHING! I don’t know where to turn and it’s getting cold. My cat is an insider but he’s freezing to death and I’ve resorted to putting a sweater on him. I need help and obviously something is seriously lacking in the vet department in my area. Surely this can’t be the first case of sores and hair loss from something besides a flea allergy on the planet?!?!
I can add pics if it could help……

My cat has been dragging her butt “scooting” on the ground and then I noticed increased trips to the litter box with little urination. She has been more vocal lately but still affectionate. I have had her for four years and she has never once peed on anything but within the last week she has been peeing on blankets and today she peed in the bathtub and I noticed her pee was pinkish she even tried to pee on my sleeping brother. I’m fairly certain this is a UTI. However, that doesn’t explain the scooting. Anyone have any suggestions? I am going to make her an appointment tomorrow for the vet. Anyone have any idea what the cost range will be? Also, my roommates have three dogs and two others were visiting for a while. Im worried the scooting could be from worms. Any other ideas? How long before contact would it take for symptoms to occur? Thank you in advance for any help. I’m very worried. Please assure me she isn’t going to die. She’s only four.

My dog was injured with a few cuts on his back, since then, he had been losing weight rapidly. These are a few things that i can observed :
- He seems very thirsty, drink a lot.
- His eyes were waterly.
- He breathe very soundly.
He’s still eats as much as he used to eat and still active.
I suspect its a worm problem that caused it. My dog accidentally drank poison 2 years ago but we managed to saved him. Could damaged kidney symptom show up this late? ( as losing weight could caused by kidney problem)

I got a golden retriever/ newfoundland/ mastiff/ rottweiler puppy a few days ago, I was told he as 8 weeks but and was born on june 14, well obviously they cant count…
He has sick with tape worms and was given medication and im pretty sure he is better because he was eating a regular amount and he didn’t have worms in his stool.
Well anyway, about a month and a half ago I lost a dog to Pave, and that dogs son, my other dog was depressed so we got him a puppy. Anyway the puppy has thrown up a few times today, at first food and after just liquid. Im afraid its parvo, but his poo is very hard and a normal colour. I have an appointment on monday for his vaccinations first thing in the Morning. Well my question is whats the first symptom of Parvo? Would vomiting come before diarrhea? Also, the dog with parvo only pooped pnce in the backyard and he hasnt been in there at all, all the floors were bleached in the house too….

We found my dog a few months ago as a stray and he recently tested positive for hookworms. The vet gave us some medicine to give him and ever since he’s had crazy amounts of diarrhea lately. He has to go out every few hours and we just get a ton of poop.
I expected this for a couple of days since all the worms need to flush out, but it’s been 5 days and still the same. Is this typical? And when we give him his second shot to make sure the larvae that have hatched are killed will we have the same scenario or will it be better the second time around?
It’s been super hot here and he’s not drinking much water so I’m worried he’s dehydrated from all the loss of fluids. He’s been a bit more tired than usual though we did have him playing in the creek all weekend which wore him out. I just want to make sure that his current actions and symptoms are pretty normal… thanks for all the input!