"The Federal grazing fee for 2017 will be $1.87 per animal unit" (cow/calf pair) per month. Plus, they are subsidized in many other ways like having Wildlife Services kill predators, having the BLM get rid of competition for forage (like mustangs) and being comped when a wolf allegedly kills a cow, even if the rancher has been negligent. So it's really quite a sweetheart deal for ranchers. Paid for by US taxpayers.    
https://www.blm.gov/press-release/blm-and-forest-service-announce-2017-grazing-fee http://www.thewildlifenews.com/2017/01/31/grazing-fee-drops-in-2017-further-undervaluing-public-lands/