And unfortunately, this says that some of the claims noted are bogus at best and unreliable at worst. They have actually researched the specific traits and their usefulness in identification.
For example, the Suwanee River Ranch folks claim
A boar's Russian ancestry is prized by many hunters, and inaccurately assessed by about as many. The single most reliable indicator of a European ancestry is the bristle...the bristle tips will be a lighter, usually cream, color.
I emphasized the key statement in bold
. However, the folks in the Texas Natural Wildlife article note
Bristles - Differences in bristle or guard hair size, shape and color among the three types of wild swine have been studied extensively (Hansen et al 1972, Feder 1978, Mayer and Brisbin 1991). Bristles of the Eurasian wild boar are the longest and thickest of the three types. Feral hogs have the shortest mean bristle length, while hybrids have the smallest average bristle shaft diameter. Substantial overlap in these measurements exists among the three types (Mayer and Brisbin 1991). Henry (1969) had stated that the bristles of wild boar had split tips while those of domestic (or feral) swine did not. Subsequent studies have shown that all three wild types of Sus scrofa have split-tipped bristles (Marchinton et al. 1974, Feder 1978, Mayer and Brisbin 1991). Bristle coloration in wild boar is primarily brown/black with light tips. However, pure wild boar also have some bristles that are all brown/black, and even a few bristles that are brown/black with a white band and a black tip. Feral hogs have solid colored bristles that are black, red/brown or white. Hybrids can exhibit any of the above bristle coloration patterns (Mayer and Brisbin 1991). Hess et al. (1985) reported that bristles of domestic swine could be distinguished from those wild boar on the basis of internal morphology. However, the wild boar sample used in that study consisted of hairs collected from only one animal.
So bristles are not reliably diagnostic even though they are claimed to be the best indicator. Y'all can compare and contrast the other traits as well.