Anyone else observed patch of white hairs?

Recently I have seen two clients with Weimaraners. Both dogs had a tiny patch of cream hairs (initally looked bald to me) on their necks.
These dogs were not related in fact one was collected from Nottingham, and both owners (I called the first one back) said their pups patch wasn't there at first it developed later. The second owner told me the vet said it was vaccine reaction.
I had never seen this before, and was quite alarmed(knowing what I know about vaccines) and I was wondering if anyone else had experienced colour changes, though not specifically just in this breed.

Weims hair often changes colour if they have been cut or hurt, the hair can sometimes grow back lighter in that place. I had a friend who's weim suffered from auto immune disease and she got a spotty rash all over her body, when this cleared up she was left with cream/off white patches where they had been and her fur had changed colour. They sadly lost her to the disease though.

wow, melanin must be absent in the follicle after injury to the skin (in weimys)?

I knew an Irish Setter years ago that didn't know how to stop - she was forever skidding along her chest and rubbed most of the hairs away. When they grew back, they grew back white.

Well to put a spanner in the works, Maddy has had cuts and grew back in the same colour, and also had cuts that have grew in slightly lighter but now as light as cream/white. maybe the severity of the injury?

I think it actually says in the standard for weims that they will not be penalised for off colour marks from injury, will have a look...

Ohhh I was right for once!

Colour:
Preferably silver grey, shades of mouse or roe grey permissible; blending to lighter shade on head and ears. Dark eel stripe frequently occurs along back. Whole coat gives an appearance of metallic sheen. Small white mark permissible on chest. White spots resulting from injuries not penalised.

Well I still feel alot better about it than before. You get a bit biased (like everything bad is caused by vaccines damage!!) It's prob. something to do with how deep into the dermal layers the injury goes, obviously a needle goes in quite far...

I'll check where Maddy's jab and microchip were done later on. I can't say i've noticed anything major though.

No I wouldn't say it was just the jab but more the actual injury. Odd though.

That is odd. Good that they aren't penalised for it though!