i was at a dog show recently and over heard someone saying that chocolate labs bleach in the sun... is this right and is there anything that can be given or rubbed on the coat to stop the sun lightening them....  i am sure the obvious answer is keep them out of the sun.... but is there an alternative?

All coats bleach to some degree in the sun(like human hair)the degree varies from dog to dog, You can use one of the many mink oil sprays that have a sunscreen but still keep the dog out of the sun as well as prolonged exposure is not good for dogsa or humans of any colouring

is the mink oil spray available in ordinary pet shops or do i have to get it some where special... i have never heard of it..

There are lots of places on line to get mink oil sprays(I opt for the non aerosol pump version from Doreen Paige's Grooming Naturally Line)

There are some links here, here, here

There other products & suppliers too