I have a cow that calved yesterday morning, this is her 8th calf. The calf is very vigorous but it is only nursing three quarters. One rear quarter it will suck a couple times, but then give up on and move to a different quarter. By now that one quarter looks pretty big, plus the teat is funny shaped (partly ballooned out, it was like that last lactation too). Also it is sore. I was able to sneak up behind this cow while the calf nursed and try to milk that quarter, I got one little stream of milk then nothing, so I see why the calf gives up on it. The cow has always been a real high milk producer, so unless the bad quarter starts effecting the other three I'm not worried about this tiny heifer getting enough. The cow has been gaining weight on grass well and doesn't look sick. I plan to cull the cow after the heifer is weaned, should I have this cow on antibiotics now? Is it likely the mastitis will spread to the other quarters, or possibly to other cows? I am thinking she will make better hamburger without the antibiotics, but I do have some procaine penicillin on hand. I already know I can't milk out the quarter, she kicks really hard.