two cows at most plus offspring.
Two cows is a minimum. All cattle should have company of other cattle "of their own age and stage." One cow and her calf is not kind, she needs another mum to share the duty of keeping the children safe! And the calves need another calf to play with.
A Jersey is a high-performance animal and needs proper, knowledgeable care.
Very high butterfat in Jersey milk, not everyone likes it. (I love it, but some don't.)
Jerseys have a very wide pelvis, so calving to a beefy bull is not a problem. A Jersey will have plenty for a calf and plenty to spare. But Rosemary gets plenty out of her Shetlands, too.
I have adored my Jerseys and would find it hard to be without them now. But if I was starting it all again I would definitely look at animals which are a little less high performance. And Shetlands would be one breed I would look at, for sure. (Whitebred Shorthorn would be on my shortlist too.)
As Anke indicates, the milk from two Jerseys - every single day - can soon become a millstone unless you have more outlets than just home use and the occasional cheese. We have a community of over 20 adults here, and more than 10 children, and because we haven't yet got ourselves set up for making hard cheese, we can't always manage to make enough product and drink enough milk from
one Jersey! (She has another cow for company, but that one is a cross and much lower performing; we have not had milk from two at the same time yet.) It takes real commitment : we have a team of milkers, a team of skimmers (although you will probably get a separator), and in order to keep on top of it, we need another team making yoghurt twice a week, soft cheese every day, (get pigs to eat the whey!), butter, ice cream... We have folks making white sauce and cheese sauce to freeze to use up surpluses, the pigs get loads when we can't process it all but we only have pigs March to October....
They eat a huge amount too! Which means more acres than you might have anticipated... And buying in or having even more acres to make your own hay and haylage for winter.... And straw for winter too, they can't be outside when it's wet and muddy... Then there's keeping them clean when they are indoors, and dealing with the mastitis when you didn't...
If you are rearing your own meat then you have two options. Send 'em off at less than twelve months, get less meat per calf but need
way less land and housing as you aren't overwintering youngstock and don't have three or even four pairs in spring and summer... Or keep them on to whatever you decide between 18 and 30 months, get more meat per animal but need significantly more land and housing.
Bringing in and rearing extra calves can be a good way of using up all the milk - but you need to know what you are doing, buying in young calves and rearing them. And if you are in a bTB area, as I am now, you may decide it is not worth the risk and prefer to keep a closed herd.