WordNet (r) 3.0 (2006):

cattleman
    n 1: a man who raises (or tends) cattle [syn: cattleman, cow
         man, beef man]
    2: a hired hand who tends cattle and performs other duties on
       horseback [syn: cowboy, cowpuncher, puncher, cowman,
       cattleman, cowpoke, cowhand, cowherd]

Moby Thesaurus II by Grady Ward, 1.0:

51 Moby Thesaurus words for "cattleman":
   breaker, breeder, broncobuster, buckaroo, cow keeper, cowboy,
   cowgirl, cowhand, cowherd, cowman, cowpuncher, dairy farmer,
   dairyman, drover, equerry, farrier, gaucho, goatherd, gooseboy,
   gooseherd, grazier, groom, herder, herdsman, hogherd,
   horse wrangler, horseherd, horseshoer, hostler, pigman, puncher,
   rancher, ranchero, ranchman, sheepherder, sheepman, shepherd,
   shepherdess, stableboy, stableman, stock raiser, stockbreeder,
   stockkeeper, stockman, swanherd, swineherd, tamer, trainer,
   vaquero, waddy, wrangler