So I breed blue ticks and there is little to no stock to be found for the breed for pictures. I know a lot of players run into this problem with a lot of breeds. Well I was talking to a real life blue tick breeder that gave me permission to use pictures of the dogs on their website. If I can show the written permission and credits could I do this?

Yes, just credit the website, with "with permission" 

And you can always message a mod with a screenshot/scan of the written permission and we can add it to your mod notes, so other mods can see it. Just as an added protection for you on top of what Binny said.