Generally U.S. Customs uses beagles to sniff out illegal meat on flights from Africa coming into U.S. Or at least they have on the trips I've made. I suspect this is because beagles have great noses, but are also well-behaved around lots of people, and not big enough to panic other incoming passengers.
Anyway, they are known among some incoming passengers (especially those living in Africa who love their dry meat) as "biltong beagles."
In the days before "biltong beagles" I did smuggle in some buffalo biltong inside my hunting boots....
