This is the brindle marking-
https://wolfplaygame.com/genstart.php?bgpic=9&shadow=Y&sex=F&base=1&rank=A&piebald1=0&legtype=0&tailtype=0&pointscolor=0&brindle=5&eyes=1&muzzletype=0&muzzlecolor=0&headtype=0&ears=0&shoulder=0&backtype=0&backcolor=0&speckletype=0&specklecolor=0&eecolor=0&eetype=0&nose=0&okapi=0&leopard=0&decor1=0&gear=0&harl=0&bel=0&som=0&pietype=0&alt=1
To breed one, you have to look for another wolf that has the brindle marking and attempt to breed it. It's usually very easy to breed for.