My Dad had one in the 60's, on the outskirts of Liverpool where his parents were living at the time. He said it made a great little pet, but stunk to high heaven
Growth plates can be seen on your pup on the front legs. Its is the boney mass just above the ankles. Nice looking pup you got there. My 2 pence worth is that it is a Sable Collie x Greyhound/deerhound (As others have said, long back and long tail)
Nothing exotic the birds come past about 20 yds in front of the hide. I use a Canon 400D and a Canon 70-210 F3.5-4.5. Its not all professional stuff that is there, alot f people there using compacts. Chap next to me had a Nikon D300 and 400mm prime F2.8