By Dr.Roy Burris,
Replacement heifers are critical to the success of your herd. Open (non-pregnant), unsound, aged cows or animals that die need to be replaced annually to maintain herd size. Since it can be difficult to find a source of mature cows that are problem-free, many producers direct their efforts toward producing or purchasing yearling replacement heifers.
Should you raise or purchase your replacements? That depends upon what you are producing now and what you want your cow herd to be in the future. Someone with a very small cow herd might choose to purchase replacements to simplify the breeding program and allow their herd bull to stay around longer. Others that are using terminal bulls (generally the larger breeds), might prefer to sell all of their feeder calves and buy the needed replacement heifers. Thereby eliminating the need for another enterprise on their farm – breeding and managing replacement heifers.
Some folks, feeling that their heifer calves are a known quantity, choose to breed and develop their own. No problem. But choosing the best ones can be challenging. A lot of cattle judges say that “form follows function”. So if you need 10 replacements select a few more, say 12, by choosing the 12 best looking heifer calves from the calf crop. Or if you have records, you might consider choosing the older calves that are more likely to be cycling at the start of the breeding season.
I remember one gentleman several years ago that would call me when he weaned his calves and wanted me to pick his replacements. He would run them past me and I would pick out his “best ones”. He would send the rest directly to market. That’s okay ‘cause “form follows function”, right?
Could there be a better way? I know that you might need sales to generate a land payment, etc. However, a different approach would be to keep most of the heifer calves and sell at different intervals throughout the years – spread your risk (but you will have smaller groups to sell).
I understand that “form follows function” so we could just go ahead and actually focus on function. In a sense, letting the calves sort themselves. Here’s what I like to do at the UKREC
(1) At weaning, sell all obvious culls – like poor doers, extremely rough hair coats, disposition problem, etc.
(2) Every time you put the calves through the chute, or move them around, take off anything that “acts up”. They’ll just disturb the other calves and can generate some periodic “cash flow”. Be critical and be generous with the “trailermycin”.
(3) Develop calves on a normal plane of nutrition – you don’t have to fatten them. Breeders should, in my opinion, put some “selection pressure” on heifers so that we can eliminate problems early in the production cycle instead of passing them on.
(4) Do a reproductive “workup” at a year of age and prior to breeding (of course). Cull those heifers that aren’t cycling, have abnormal reproductive tracts or don’t have sufficient pelvic area to have a normal-size calf. They can be then sold as feeder calves.
Disposition is very important – you don’t necessarily have to assign a chute score or measure exit speed but the way that they behave “under pressure” is a great predictor of their future – administer trailermycin as needed. Those that do make it through this step are good candidates for breeding.
(5) We do one round of timed A.I. followed by a short “clean-up” period. Pregnancy diagnosis is done as soon as possible so that open heifers can be removed and sold while they are heavy feeder calves.
Out of the bred heifers remaining, we select the ones that we want to put back in the herd (usually AI bred) and the rest should be good enough and eligible for bred heifer sales. Selling bred replacement heifers is another potential enterprise on the farm – especially if you have a quality cow herd, you are selecting for maternal traits, have a good health program, etc.
Heifer selection is a continual process. The final evaluation won’t be until they wean their first calf. They need to meet these criteria: (1) wean a good calf, (2) maintain good body condition, and (3) breed back early in the breeding season. If they do this, they just graduated to the cow herd. Congratulations.
Form does follow function but don’t get so concerned about appearances that you forget about function. I’ve seen some pretty common looking cows that were outstanding producers. It would have been a shame to have overlooked them.
Source: osu.edu