I strongly disagree with some of tchick's advice!
Baby calves become dehydrated extremely quickly - more quickly than most people realize or respond to.
If that calf becomes the least bit dehydrated, it will weaken and die. It will be too weak to nurse, especially if it has to chase a new fidgity mom around to get its milk supply.
My vet says the biggest mistake most people make is listening to people who say, "It will nurse when it gets hungry" or "Wait and give it time to mother up." If there is a problem - a calf that was pulled and is a little slow, or a new heifer that isn't observed mothering & nursing her calf, he recommends bottle or tube feeding until the calf is actually observed nursing from its mother.
Yes, if you have the facilities and can do it, do confine the new mother in a head catch and make sure the calf is able to get its food supply. Mother's milk is always best for the calf, but the most important thing is to keep the calf hydrated with milk or milk replacer so it can get strong enough to nurse - even from a reluctant mother. Your calf will be at risk for sickness if it didn't get colostrum in the first 12 hours, too. It won't have the antibodies to fight off infection. If it did nurse in that first 12 hours, it should be ok.
First calf heifers often are shocked when they see their calf for the first time. It's best to keep them separate from the rest of the herd and let them mother up. BUT be sure the heifer doesn't attack the calf - it doesn't happen too often, but is not unheard of. We keep our first calf heifers with their calves in a corral for a day or two before turning them out with the herd. It is also not unheard of for an older cow to take a calf away from it's first calf heifer mother if the pair hasn't mothered up before being let back into the herd.
I don't think feeding the calf increases the chances it won't nurse - I think that's an old wives tale. It has been our experience that when a calf has had to be tube for a day or two or three it starts nursing from its mother as soon as it is strong enough. Sometimes calves that have been pulled act a bit dazed for a few days and need a bit of extra time and help before everything kicks in. All of a sudden you'll see a big difference in the calf and it will act just like all of the others.
One more thought - if the heifer is left out with the herd, another calf may be nursing (snitching) off of her. Heifers aren't as aggressive at chasing off other calves as older cows are. She may let other calves nurse and you will think her own calf is taking the milk, unless you have them confined in a corral.
The heifer should settle down in a couple of days, even if she's confined. Just kind of keep things quiet and observe from a distance or in a very quiet way.
Rafter L Murray Greys