Vet’s Voice by Dave Barz: Pre-culling, calving considerations
Fall is definitely here and the harvest is getting a good start in our area. I even pulled out my sweatshirt several times last week. Most of our producers have a lot of hay for winter feed, but now there are also some very large silage piles. Now is the time to take inventory of your herd and your feed stuffs to determine your winter needs.
The most important inventory is your cow herd. You need to determine how many productive females you have for calving next spring. The best way to accomplish this is with a pregnancy check. This fall most of our cow herds are at about 90-percent pregnancy rates, but we have had some herds with 30 percent or more open cows. Now is the time to understand your needs if you have had reproductive problems.
We are ultrasounding heifers and cows now. This is a great way to stage your cows into exact calving intervals. You can sort the cows which conceived in the first 21 days of the breeding season (this should be 70 percent of your herd). Cows which are in the first group should be scrutinized very carefully for problems. We are reluctant to cull a cow carrying an early calf, but if she’s late, she might go. Remember, the earlier you pregnancy check, the more chance of embryonic death resulting in a cow that doesn’t calve. If you test at about 60 days, you may have as high as 10 percent which don’t calve. Late term testing (seven months plus) results in only about 1 percent loss rate.
Rectal palpation is the most common form of pregnancy diagnosis. Good palpaters will be able to group your pregnancies by month. When you process your cows be sure to write down the data so you have a record. Also rate any lameness or other abnormalities the cows may have. This will give you a good basis for culling later.
What is the average age of your cow herd and what is your culling percentage? In our area we don’t cull because of age, in fact we go to range areas and purchase older cows which are removed from herds. Many of you try to remove cows which are 10 years old. This means your culling percent is 10 percent. If you remove defects and opens, you may reach 15-20 percent. Culling is an expense which needs to be computed into the cost of your heifer development and must be pro-rated over the life of the heifer or cow.
Compile a list of fall and winter grazing. It is always less expensive to have your cows harvest winter grass and residue feeds than to bale them. Try to plan a timeline or schedule for movement from one area to another. Remember Mother Nature may not honor your timeline, but as winter progresses it is best to move cows closer to feeding areas if needed.
You need to estimate or count your harvested feed. While you take this inventory be sure to pull samples for analysis. This will allow you to formulate rations which will allow your cows to maintain proper body condition (BCS) during the cold winter. We have some clients purchasing wet distillers grains and mixing it with straw and tarping for winter supplementation.
Fall is also a great time to prepare your calving areas. Make sure fences are in good shape because in January it will be tough to set posts and build fence. Gather bedding and feed before the snow piles up. Remember the Boy Scout motto, “Be Prepared.”
Now is the time to prepare your cow herd for calving next spring. Consult your veterinarian, nutritionist, or extension specialist about management strategies and feed formulations to assure you have enough feed to keep your cows in optimum condition for calving. It’s much easier and less expensive to add pounds to your cows this fall than during winter in late gestation. Preparedness will make your cow-calf operation easier to manage and more profitable.