Just a few thoughts from someone who has also done it and am still doing it to some extent.
Everything that KY Hills said is very true. I've seen and done what he has done.
I am a milk tester and have access to calves. You get to know who does a good job of getting colostrum into their calves.... and some of the farms the "bugs" they have are not compatible with the "bugs" on your farm. I have 2 farms that I get calves off of now. They always have a good start and do good for me. One farm I have never been able to raise a calf.... our two farms "bugs" are just not compatible. They do a good job of raising up their own calves but I will never buy another calf from them. Doesn't work.
Since you have a few and are making some money at it, you have a feel for them. The thing is when you get to a certain number, it may become unmanageable as far as letting the cows in to the calves. You will have calves at different stages, and if you get a case of scours, it can go through them all in a minute.
I have one in the barn now, with 3 calves, and 2 more young jersey cows due,that have raised calves before, and 5 heifers. I wanted to do milk/cow shares and started planning this, 2+ years ago when I got heifers off a dairy. They are mostly all jersey/hol cross heifers. There are a few jersey/ang crosses that will be used just like a beef cow and just raise their own.
I have had as many as 5 cows in the barn at a time. Any more than that I did not have the space to make sure that all the calves would go on the cows and get enough milk. I normally had 3 per cow. I used to raise them for 3 months then switch them out for a second set too, when calves were cheap. Now it is not worth the time or trouble. Plus once I get a group of 3 well established, I can let them out with the cow and then just bring her in for grain once a day to help keep her production up. The calves will learn to come in and out the creep gate and I put a little grain in the bunk for them so they learn to come in and then it is easy to catch them when I need to sell, or wean or move or whatever.
My nurse cows are pretty tolerant and I will see calves nursing off a cow that is not "their momma" . But this gets into problems if there is a difference in ages as the older will drink faster and push the smaller ones off.
I do make a little money with them, but not much to justify the time and the grain I feed to keep the cows in good flesh and producing enough to feed 3. KY Hills is right about the dairy cross calves getting discounted at the sales; see it here too. One of the reasons I do it is I LIKE MY DAIRY COWS. They have to "pay their way" and raising several calves does that. We sell a little beef here and so the dairy cross calves will do okay for that.
You have to know your market... But just realize that going from 2 to 15 is like going from crossing a little creek to trying to cross the Mississippi in spring thaw. The numbers will not just quadruple or more as the complications will make it more like 2 to the 10th power..... If you get one or two more at a time, maybe you can do it. But to go all out and go from 2 to even 10 is a HUGE difference.
I am not trying to discourage you.... but don't want you to all of a sudden take on more than you can begin to handle and choke on it and do a crappy job with all of them ; when you were doing a good job with a few. It reaches a point where it just might be too many all together.
I will be farming my 5 heifers out to a dairy for this first lactation. I had my ankle replaced this past Feb., and it is doing real good. But the knees are really bad and they are next. No way can I handle them all in the barn. The 2 jerseys have done this so I hope they will take calves pretty well and get established before I do surgery so all they will need is grain daily. My son is not a big fan of the dairy animals because the calves do not bring what a beef feeder 500 lb animal will, so thinks that they are a waste of my time for more than just one or 2. I also do milk some for the house, so there isn't enough time for me to get the heifers established, tame and all that..... and he will only screw it up due to lack of patience with the dairy animals. So, I will get my physical limitations fixed and then maybe do it the next year.... we will see. But I honestly am not sure if I can handle more than 5 in the barn even if I am able to get around real well.... Maybe get them on a different schedule, so there are only a couple fresh and a couple with older calves so easy to keep them separated.....
Good Luck to you.
