I was woulding if anyone have fed there dog on a vegetarian deit? I have a greyhound and he has very senistive skin. I have try him on a fish diet with no look. He is fed on very good quality food.
His coat is dull has no shine on it sometimes it can fill quite coarse when you toruch him. When I brush him he alway has a lot of flakes and when I check his skin you can see alot of dead skin in his coat. His noise is not a wet noise it is alway dry so it splits all the time so I put vaseline on his nosie to help.
I have try him on a raw diet but he dose not like raw meat at all.

In what way is his skin sensitive?     What are the symptoms apart from dryness?

What is his tummy like?   Stools?

What food is he on now?   What treats does he get?     

Has he been tested for food allergies?   Or other allergies?       Have you tried an elimination diet?

Before going down the vegetarian route, it would be useful if you gave more information ;-)

Have you seen a vet ? Greyhounds can be prone to under active thyroid which could account for some of the symptoms you describe .. A blood test would detect thyroid problem. 
K

Edit : here is a link with I of on under active thyroid http://www.vetinfo.com/symptoms-of-underactive-thyroid-in-dogs.html

It is quiet "possible" that your problem is caused by the use of our "convenient" complete dry kibble food, of which a very high percentage are cereal based. Cereals in the wild are only seasonal and not 52 /7, it is so un natural !
Try again the raw meat, but just very lightly cook it, this can make a big difference to the texture and taste for your dog untill he is used to taking it completely raw. Add some vegetables to the meat feeds once he accepts the fact that meat is good.
You will not get a result overnight but given time you might be surprised in the difference of your dogs coat and skin.

I've seen Wafcol Vegetarian work well for some Westies with poor skin, although I would prefer to try raw and Wafcol Salmon and Rice first. 

I have a saluki that has been fed on a vegan diet for about 6 years now and is doing great (he is nearly 9 now). In his case it's because he is sensitive to all animal protein.

The symptoms you describe could be food allergy, but it is very rare that a vegetarian/vegan diet is needed. Many dogs are however sensitive to common ingredients like rice for example, so perhaps an exclusion diet of some sort would be more useful than go vegetarian straight away.

And yes, thyroid test and a general blood test would probably be a good thing as well as various conditions can cause skin/coat issues. :-)