This is not for SAR but
Blue Lacys are known for their almost-instinctive tracking ability. They do blood tracking mostly. When I owned one we had a Blood Trailing seminar out in West Texas and a tester came from the United Blood Trackers Organization
http://www.unitedbloodtrackers.org/.
The UBT-I test is 400 yards, with at least 2 turns and one wound bed, aged at least 2 hours, and using 8 oz. of blood dropped intermittently along the track. There is a game part at the end (Deer skin or leg, etc.) It is NOT a 'drag' test.
There was a 4.5 month old Lacy pup that ran the Level I track and passed with flying colors. This was the first track the pup had ever been on. He did take a little longer to run it than some of the older dogs, but he found the game at the end!
My Lacy, Ranger was 14 months old and I'd had him on less than 10 training tracks total, and he passed the Level I with no problem. Under extremely dry, dusty conditions with wind gusts of 25+ mph and the tester said he counted no less than SIX different wind changes during the test. Ranger did it off leash at nearly dead run, missed the first 90 degree turn but successfully redirected himself, and finished through scrub brush and mesquite in about 15 or 20 minutes. I just huffed along behind!