Puppy fade?

Hi all.
I feel so sad, I had to have one of my puppies put to sleep this morning
I have had to bottle feed him since he was born because mum kind of rejected him.
He has born VERY small and not even my vet thought that he would make it through the first few nights...... Well he made it until today (Nearly 4 weeks)

This morning i found him all limp in the corner of the whelping box, Worried i called my friend to come over asap to take me to the vets with him, I fed him half a bottle of milk on the way and he was fine drinking....... The vet said he had puppy fade, i was confused because of that i had read up on that its normal for puppies from 0-3 weeks I aksed her if she was sure? Yes said yes and then said the best thing to do would be to put him to sleep.
I said i would not agree to it unless he was really suffering and was happy to pay whatever it cost to help him back to health but she stressed it would be better for him to put him to sleep.
I had to leave the room whilst the vet decided what to do and asked my friend to stay with the pup whilst i went to compose myself knowing that the vet might have put him to sleep...... 3 mins later my friend come out with the poor boy having been PTS.

I have so many questions,
1 whats the likelihood of him having puppy fade at 4 weeks?


2 Could there have been anything that might have fight back fit?

3 am i just beating myself up over this?

All the other puppies have been fine but now i am worried about them after today.
Is there anybody that could shed some 'Experienced' light on what i should watch out for with puppy fade?
The internet sends mixed messages as to what to watch out for.

One upset guy

Hi
I have never had a puppy fade at four week before, I personally think that it could be some other problem the puppy had. The vets put most deaths of young pups down to fading it covers a wide variation of problems. we have been breeding for over 20 years now and lost a few pups over the years and it has always been put down to fading, but this is usually in the first week. About 5 years ago we lost a few litter of puppies, and one of the things that was suggested to me was canine herpes. apparently this is the cause of most puppies fading. We then started to have our bitches vaccinated for this. They get the first one on the day of mating and the second one at seven weeks in whelp, and up till now we have had fantastic results.
hope this has helped.
Karen

Thanks Karen
I see what your saying.
I think because it all happened so sudden its really hard accepting whats happened and i guess my mind is just doing overtime

i know nothing about breeding so cant be much help, but was sad to hear what happened to your poor boy. dont beat yourself up about it, im sure the vet knew what was best and you followed her advice.