poorly pup

Question
hi my border collie pup is 10 weeks old, he had sickness and diarrea ( mucusy with blood) since we had him at 8 weeks old, he was so poorly and dehydrated that he had to have iv fluids on 2 occasions. he tested negative for parvo virus and had blood tests that showed he was aneamic and that his liver function results were low. i was perscibed zantac and prokolinand special diet for him, now 2 weeks later the vomitting and diarrea has stopped, he is now gaining a little weight and eating and drinking however one minute he has normal puppy behaviour, biting playing etc then the next minute he is lifeless again, its totally baffling me, he is up and down like a yo-yo. i did notice this morning he was full of life, then when he had his food he, laid down and become depressed again. i am still giving him his meds, and i am awaiting for him to have an xray. any ideas would be greatly appreciated as i am totally at a loss. thankyou

Answer
I would have this dog tested for protein losing enteropathy, mal-absorption problems, cancer (yes as young as 10 weeks old) and other diseases of the gastro-intestinal tract. A negative test for Parvo really means nothing. He sounds like he had  gastro-intestinal hemorrhagic disease, which is the same thing as parvo but with unknown causes. Lots of different viruses cause these.

If the symptoms continue after the initial viral attack is over,then the virus could have caused some damage that is causing the dog to not absorb his food properly. Pancreatic enzyme deficiencies will also cause this. As a result, he is not getting enough nutrients to have any kind of sustainable energy.

Liver function and pancreatic function go hand in hand. You need to have him tested for enzymes, digestive issues and absorption issues.

He should be on a low residue food for now such as Hill's I/D which is made for high nutrient content with a low residue so that the food passes through without irritating the bowels any more than they have to be.

A trial on powdered enzymes is good idea also.
Xrays will only show some thickened bowels but without a biopsy or at least some more tests for enzymes/liver function you won't get far.

An ultrasound might be money better spent. Trials with the food and powder to start are more cost effective for you.

Using Kaolin (a clay) and antibiotics was a start but not enough to address the causes.
His food (I don't know what it is either) could also be affecting him if he has an intolerance to it or a true allergy. It could make him very weak once he eats it, although that is pretty rare.

I would discuss the above with your vet and see what you two can come up with from there.

I hope he does well. Please let me know what you find out.