Inyati, I was one person who mentioned that my heiferettes pretty much stopped growing (at least when measured by chest girth) after they were bred. My average cow is on the big side of "medium", most of them maturing around 1400 lbs or so. Unless a heifer calf looks particularly nice, they are usually around 650 lbs at weaning, and somewhere around 850ish at breeding, and close to 1100 at calving time. I breed at 14-15 months, but if I could wait another couple months to say... 16-18 months that would be what I consider ideal, but that would make a mess of calving time.
As calves, the mothers and calves all get the same food, but once I've decided on which ones I am keeping as replacements, they get the best I have, and as much of it as they want. As they're long yearlings and pasture season ends, I take the heiferettes and the first calvers up into the corral and feed them better hay, and they don't have to compete with the big mean girls. Typically, my first timers will wean 625 lb steers, and 575-600 lb heifer calves. One in particular last year made an exceptional steer, but it took a lot out of her.. she was really nice when she calved but by weaning she lost a lot of condition... I want to make sure she's in shape for next year and she's gained back her condition now.
Of last year's heifer calves, 2 of them have been coming into heat regularly since september (they were both 191 days old). I was glad to have them away from the bull in time!
We used to breed at 26 months, but found it took too long to build up a herd, and we still had some that weren't any good and you put too much effort into them to want to send them off, so you'd wait for the second calf to decide, at which point they're 4 and it's getting to the old side for good meat and you'd take a hit at the sale barn.. What I can say is we never had calving problems with them, while with the first calf at 2 years old you do have to watch them closer
That black heifer there looks like she'll be nicely ready to breed in a few months time.
