No one here has actually revealed what it cost to keep a cow. Or various breeds.
First I am assuming that the cow in question is being raised as inexpensively as possible. Not for show but just to breed back and produce calves every year.
A lot also depends on where you live, here in Texas we have to feed hay for a little less than 3 months. Our cows average 2 round bales per head. Since we grown our own hay the only cost is fertilizer and cutting and baling cost. Varies each year depending on rainfall and haven't figured it recently but guessiing around $25 per bale. So that is 2 bales per cow or $50 per cow. We also buy trace mineral salt blocks, not very often, don't know how much each cow consumes. So I will throw in $5 for salt. OK, eartags for flies, not here, don't use them. Let the egrets eat the flys. OK, tick control, no cost, brahmans don't have tick problems. Let's see, what else goes into keeping a cow. Hoof trimming, don't think so, that is what rocks are for. Oh yeah, the vet, ok they go when they are weaned heifers to be dehorned, branded, bangs shot. But that is a one time cost so can't really factor it over the life of the cow.
Ok, another $5 per head per year for vet. Palpation is a good idea. Maybe another $5 per year. Don't do it every year. Get rid of the ones that don't perform.
My cost to keep a cow per year breaks down to:
Feed .......$50
Salt........ $5
Vet......... $5
Pg check.. $5
Looks like total is $65, sounds to low so I will say $100 per year per head.
Hope this helps