My 2 month old puppy was fine this morning and this evening, he became very lethargic, dehydrated, decreasing body temperature, shallow breathing, rapid and thready heart rate, lack of urination, and lock jaw. What's wrong with my puppy??

Funny you seem to know all the buzz words, but if you know for certain your puppy is that bad off, why are you waiting here for an answer ? You should be at the vet immediately.

Tick

Wow, this could be anything from rabies to distemper to parvo! Your pup needs to see a vet immediately! We can only guess at what might be wrong, we can't diagnose him over the net.

I agree with Aurora, it could be a ton of different problems. This pup needs to be taken to the vet right away, he could die :(

Sounds like distemper...

Please contact your vet.

At the moment I asked this queston the puppy was already with a doctor he was going to keep him over night to watch him I love my babies like I love my children and I am impatient when it comes to answers I was hoping to find something,some reason. When I took the pup in, the vet said he looked like a parvo puppy and would do the necessary treatment I wasn't convenced that it was something else. The puppy that morning was fine ate breakfast by the afternoon feeding had all the symptoms I described at 5:24 the vet called to let me know my puppy was gone. They kept the remains but have not yet called with a reason I'm hoping to hear from them soon I am worried about the rest of the litter there are five left parvo, rabies, or distemper were not the cause of this puppies death

Where all the puppies up to date on their shots?

There's really no way for any of us to know what happened. The only way for you to find out for sure what killed your puppy is for the vet to perform a necropsy which will likely not be free.

I'm sorry for your loss. Hopefully this was an isolated case and the other puppies will be fine, but there's really no way to know without knowing what killed the pup.

So the vet ruled out all 3 diseases, but doesn't know what killed the pup? Puppies can die from fading puppy syndrome much like SIDS in human babies, most of the deaths caused by FPS are from diseases or abnormalities developed in the uterus. Second most common cause of death are respiratory illnesses.

Birth defects, which include both genetic as well as drug or environmental causes, account for a large number of fading puppies as well.

I'm sorry for your loss, and apologize getting here too late to do more than comment. In my experience, this follows the pattern of a puppy with severe hookworm infection. With parvo, expect diarrhea and vomiting and absolutely no desire to eat or drink. Death is normally due to toxins absorbed from the 'sick' intestines. The fact that he ate and drank the next morning is not characteristic for a Parvo puppy after one night's treatment.

Hookworms are quite common, are not simple to eliminate with one treatment, as it is a developing infection. Briefly, hookworms are found in the intestine, where they cause a significant blood loss (anemia)when there is a heavy infestation.

Most puppies, as they become more and more anemic, are able to throw off most of the signs of being severely ill. In the final day or two, however, quite suddenly the gums have turned very pale to white. It's almost as if the body has finally given up, or lost the ability to stay ahead of the infection.

This also causes the abnormal respiration as the blood isn't capable of carrying enough oxygen to satisfy the body's demand. Metabolism also drops for the same reason, and the pups lose body temperature. The pup is lethargic, won't eat, or drink, dehydrated because of the blood loss, and often dies before getting any vet attention. It isn't unusual for the whole litter to be lost if a correct diagnosis isn't made and treated.

A fecal test is confirmatory for the problem, but many of these severely affected pups still go into shock and die without aggressive treatment, including often a blood transfusion. Your best bet is to gather some 'community' puppy poo, (several puppy samples... you're going to treat the whole litter if it's hooks) and some of Mom's as well, and have the vet test it.

It is almost impossible for a litter to have only one pup affected, as most of these severe infections were transmitted in utero, or before delivery. Older dogs are not often as severely affected as pups, strictly because of the size difference. It takes longer for older, bigger dogs to lose as much blood as a puppy, as a percent of total blood volume, but they still become anemic and need wormed as well.

Generally, the first treatment goal is to kill the worms, (often in the form of an injection) and allow the intestines to recover from the effects of the worms and treatment. Then, it's a matter of nutritional recovery, both for the body, and the blood loss. Then, follow up treatment to completely eliminate reappearance of the undeveloped worms still in the puppy's bodies. Usually, two more wormings are sufficient.

I hope this helps, and best wishes.