– Brooks Warner, OSU Extension Educator, Scioto County
We are in bull sale season and many of you are looking for a new herd sire.
Before making sire selections, I encourage you to ask yourself, “What are my operation’s goals?” and select your next herd sires with your operation goals in mind. Operations should buy the bulls you need and not the bulls you want.
Wanting to go for the stylish bull, the thickest bull and/or the biggest weaning and yearling weights is easy. However, beauty is (sometimes) only hide deep, and single-trait selection is never a good idea.
For most operations, the main goal is profitability, and a few different aspects come together to help you achieve a profitable beef herd. Some of the most important aspects of the profitable beef herd equation are:
- Live calves
- Fertile, easy keeping, productive cows
- Optimal performance at the farm and ranch, in the feed yard, on the rail and on the consumer’s plate
Sire selection should be a combination of visual evaluation and expected progeny difference (EPD) data. A deep understanding of EPDs can help you determine which bull is best for your operation.
Live Calves
Typically, calves born with assistance, such as hard pulls, have a higher death and sickness rate than calves that are born unassisted. Three primary EPDs predict the ability of a sire’s calves to be born with unassisted delivery: calving ease direct (CED), birth weight (BW) and calving ease maternal (CEM). Calving ease direct (CED EPD) predicts the percentage of a sire’s calves that will be born unassisted, BW predicts the difference in weight of a sire’s calves and CEM predicts the percentage of a sire’s daughters who will calve unassisted.
Calving Ease Direct (CED) Example
| Bull | CED EPDs |
| 1 | +10 |
| 2 | +18 |
| Difference | +8 |
Bull 1 should sire calves that are 8% less likely to be born unassisted than Bull 2.
Bull 2 should sire calves that are 8% more likely to be born unassisted than Bull 1.
Comparatively, higher numbers mean more calving ease.
Birth Weight (BW) EPD
| Bull | BW EPDs |
| 1 | +1 |
| 2 | -4.5 |
| Difference | -5.5 |
Generally, smaller birth weights equal fewer assisted births.
Bull 1’s calves should weigh 5.5 pounds more at birth than Bull 2’s calves.
Bull 2’s calves should weigh 5.5 pounds less at birth than Bull 1’s calves,
Calving Ease Maternal (CEM)
| Bull | CEM EPDs |
| 1 | +10 |
| 2 | +18 |
| Difference | -8 |
Comparatively, higher numbers mean daughters have more calving ease.
Bull 1 should sire daughters who are 8% less likely to have their first calf unassisted than Bull 2.
Bull 2 should sire daughters who are 8% more likely to have their first calf unassisted than Bull 1.
Fertile and Productive Cows
One of the most important traits related to profitability is a cow’s ability to get bred in a set breeding season. For a cow to start cycling (be in estrous), it has to be in adequate condition. According to published research conducted by Short et al., the following is the priority use of energy by a cow:
- Basal metabolism
- Grazing, other physical activities
- Growth
- Supporting basic energy reserves
- Maintaining pregnancy
- Milk production
- Adding to energy reserves
- Estrous cycling and initiating pregnancy
- Storing excess energy
You’ll notice that cycling and establishing pregnancy is low in the order of priority of energy use. Thus, a cow will milk to her genetic ability before cycling and getting pregnant. Milk is an expensive trait because of the additional energy needed not only to lactate, but also have enough body condition and energy reserves to cycle and breed.
Milk EPDs do not predict the daughter’s milk production. Milk EPDs predict a sire’s daughter’s milk and mothering ability as expressed in his daughters compared with daughters of other sires. In other words, it is that part of a calf’s weaning weight that is a product of a cow’s ability to milk and mother her calf.
| Bull | Milk EPDs |
| 1 | +35 |
| 2 | +20 |
| Difference | +15 |
The calves born to Bull 1’s daughters should weigh 15 pounds more at weaning than those of Bull 2.
This estimated weight is from the mother’s milk production.
EDITOR’s NOTE: Learn more about selecting your next herd sire by participating in the Bull Buying School in West Union on March 22.