sorry it took me so long to get around to this, i took Sonic & Copper (in laws' 9 YO yellow lab) out looking for jacks yesterday and it was a long fruitless day.
first i'm going to cover one or two mistakes on the pit dogs (i think i am the only person here that has actually trained, handled & attended matches).
1. THEY WERE NOT bred to kill other animals & especially not dogs. They WERE bred to NOT QUIT A FIGHT (which is also the definition of gameness and so cannot HONESTLY be tested any other way and only a few animals will fight long & hard like two game dogs). This gameness comes from a high level of intelligence (enough to foresee outlasting the other dog to win) and so they can be trained to other activities. The gameness, intelligence & athleticism allowed the pit bulldogs to excell in other venues like the rat & badger pits and in modern hog catching & weight pull.
2. DA & gameness are not directly related (although they are often associated), there were infact plenty of old gamedogs that were ice cold until you dropped them in the box. now since the pitbulldogs came from mixing game terriers & game bulldogs that were used to fight OTHER animals (sometimes in groups) a lot of the resulting dogs were cold and in order to reduce litter waste (nonworking dogs from a working litter) game dogs w/ a higher willingness to engage were bred from and as a side effect a higher level of DA developed in the breed (s). also when dogs other than the bull & terriers were used in the box they tended to be both game & DA (for example a few boxers here in between WWI & WWII and a retreiver in britain in the 1880s had good records & were bred from). chalking it up to "training or how they're raised" is BS, it is firmly planted in the genes. it is common in ALL breeds developed specifically for dog fighting shar pei, akita (yes i know about the bear hunting but for the last century for every hunting akita there were 5 fighters), tosa, gull terr, bully kutta, presa canario and every line/breed of bull & terrier all have higher levels DA than other types of dogs, including some that routinely fight strange or wandering dogs like LGDs & curs.
Romy
the BMC, catahoula & to a lesser extent the Plott all have bad reputations among houndsmen as being DA. IMO the reality is that they don't take crap from other dogs and tend to finish the fights the other dogs start. I know several bear doggers that don't realize their dogs are DA and just think they somehow keep getting on "bad bears." somehow they manage to miss the fact that the bites on the dogs are too small to come from a 250 or 300# bear. IME treeing walkers are the worst for DA, but that comes from the aformentioned nimrods breeding their "tough bear dogs."
now i have seen hog dogs i would call game but i don't think hogs in general are good measures of gameness, nor are most wild animals. here are the animals i think could most consistantly test a dogs gameness (assuming comparable size) on a wild hunt, otter, badger, groundhog, nutria, beaver, coon & maybe coyotes & bobcat.
i haven't heard of a lot of DA in sighthounds (in fact i only know of one guy that seems to have a problem w/ it in his line).
sighthounds & curs (and hunting bull & mastiff breeds) are meat dogs bred for subsistance first & sport later. scenthounds originated purely for sport and so killing dogs were not desirable. in NA, SA & Africa where they are used for predator control scenthounds w/a willingness & even desire to kill have become more common, even predominant in some areas.