The answer is the same. Your "friend" bred irresponsibly, and is 100% responsible for the results. She didn’t draw up contracts, she gave the dogs away for free to whoever, and apparently hoodwinked them on top of it all. She deserves what she is getting and needs to pay this person for treatment.
I do not see a demand to pay for a dog falling in the lake. I see a demand for her to pay for the spread of the Sarcoptic Mange, which is reasonable to me. She touched the pups, she touched her other dog, and she touched the rats. They now all have it, because your "friend" was not honest.

ETA: LOL! A TD does not change the fact that this "breeder" needs to pay the piper!
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Secondly, I suggest you get this owner to bring the puppy back, so it can be checked by your vet. Alternatively get both vets to speak to each other. Right now you only have the word of this owner about what’s going on.

Having been on the receiving end of a situation like this with a puppy I bought in good faith, at the very least I’d expect the breeder to be making the right noises, and maybe, once both vets have spoken to each other, or your vet has seen the puppy if possible, maybe offering to at least make a contribution towards vet treatment, even if the owner was ‘warned’. Obviously the costs involved with falling into the lake (£400 – for what?) are not the responsibility of the breeder.

And to be honest, siding slightly with the breeder here – had this puppy been checked by the owner’s vet within the first 48/72 hours, any health problems should have been found, and treatment begun – well before other household pets were compromised.

Keep the communication open before this deteriorates into a legal situation.
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What your friend should have done was drawn a sort of contract saying that the puppies have mange and have the buying party sign it with a few witnesses, so that she had proof that the person took the puppies knowing they had mange.

As far as the dog falling in a lake, that was the owners responsibility and not hers.

It’s not unheard of for a vet to misdiagnose mange, though whether it was the vet she went to or the one the other woman went to is hard to say.
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http://dogs.lovetoknow.com/wiki/Free_Puppies_to_Good_Home

The main thing your "friend" is at fault of is being an irresponsible, backyard breeder in the first place and breeding from a mongrel without prior health testing, that was obviously not fit and up to rearing a healthy litter of puppies.

The next thing your "friend" is guilty of is rehoming sickly puppies. Your "friend" should have paid for their treatment and waited until they were clear before rehoming them.

Demodex is a result of a weakened immune system and is totally different to sarcoptic mange, but because these puppies were were already compromised and already sickly, then any one of the puppies was more suceptible to catching other diseases, including the sarcoptic mange, which is probably what happened with this puppy.

Your "friend" should have insisted that the new owners of all these puppies should have taken the puppies to their own vet within 24 hours for a full health check and to receive any ongoing treatment from their own vet as needed.

The new owner of the puppy with sarcoptic mange is now responsible for this puppy and was a fool to take on a sickly puppy at all. Probably only doing so because it was free. Therefore, she is, like so many other victims of this nature, now paying for her desire to "get something for nothing".

No I do not think your "friend" will be forced to pay for this puppy’s vet fees although I do think your "friend" should and would do if she had been a reputable and ethical breeder in the first place.
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EDIT – Bunk, Humans can most certainly get sarcoptic mange and it is VERY contagious!
http://www.dr-dan.com/sarcopt.htm
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1. I didn’t think that sarcoptic mange could be treated by advocate?

-No, it can’t be.

2. Is my friend in any fault?

-Hard to say.

Demodectic mange would be the mange a vet would suspect in young, indoor-raised puppies with an unhealthy dam, absolutely. That’s what she was told by HER vet was going on, and she dutifully treated for it and informed puppy buyers.

The issue is whether demodectic mange was the right diagnosis. Dogs with sarcoptic mange tend to scratch uncontrollably, so even though is very hard to diagnose with skin scrapings, chronically itchy puppies should have suggested to your friend and her vet that sarcoptic mange was potentially the issue. Skin scrapings fail to find sarcoptic mange mites AT LEAST half the time, and treating for it–the maybe mange test- is often necessary to properly diagnose sarcoptic mange.

The OTHER possibility is that the pup got sarcoptic mange after going to the new home.

3. Shouldn’t they have taken the puppy’s to the vet and got them checked out anyway?!

-Yes, absolutely, within 24-48 hours of bringing the pups home. Your friend should have required this in her contracts.

4.Also how could the puppy’s have developed sarcoptic mange if they where diagnosed with demodex mange? none of the other puppy’s have sarcoptic mange they all have demodex mange?!

They could have gotten sarcoptic mange by being around another animal with sarcoptic mange. It spreads quite easily from one dog to the next, from racoons, foxes, etc.

Yes, they can actually get both.

Are you 100% SURE the other puppies don’t have sarcoptic mange? If you are, then this one puppy got it after he went home.

http://www.marvistavet.com/html/body_sarcoptic_mange.html
http://www.marvistavet.com/html/demodectic_mange.html

ETA: Contrary to what another poster said, humans CAN get sarcoptic mange, although it’s a self-limiting infection in humans as the mites can’t reproduce on humans.

ETA: My dog had sarcoptic mange when I adopted her from the shelter. She had been in a foster home (as were all their pups) and the shelter didn’t know about the mange.

Because i took her to the vet w/in 24 hours, I had no problem at all getting the shelter to reimburse me for the costs of treatment.

My dog was one on which the scrapings didn’t find the mites, although she couldn’t even eat without stopping to scratch herself, so we began a series of ivermectin injections that cleared it. (The so-called "Maybe Mange" test.)

She had been living mainly outdoors with the foster family’s other dogs, so we’re pretty sure it came from foxes and ALL their dogs also needed treatment because it’s so contagious!
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All the excess babble posted has nothing to do w/anything.
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