Weaning percentage (calf crop)
80%
- 90%pregnant
- 88%calving
- 9.1%calves lost
- 40 calves weaned from 50 females is a 80% calf crop. The CHAPS herds weaned 91.4%.
- 90% of the females exposed were pregnant.
- Calving rate is 88%. Nebraska's goal is 90% or higher.
- You lost 4 calves before weaning: 9.1% of the calves born, or 8% of the females exposed.
How we work it out
- Pregnancy rate = pregnant ÷ females exposed × 100.
- Calving rate = calves born ÷ females exposed × 100.
- Weaning rate (calf crop) = calves weaned ÷ females exposed × 100.
- Calf loss = calves that died before weaning ÷ calves born × 100. Nebraska also gives it over the females exposed.
From Nebraska Extension G2094. Texas A&M gives a second pregnancy rate, over only the females checked. We show both when you did not check them all.
An example from Wisconsin
A farm had 50 cows with the bull in 2024. In 2025 it weaned 40 calves. That is 80%.
The CHAPS herds weaned 91.4%. So this farm has room to do better.
Questions
How do I find my weaning percentage?
Count the calves weaned. Divide by the cows and heifers that were with the bull, then times 100. 40 calves from 50 cows is 80%. It is also called the percent calf crop.
Why divide by the females exposed, not the calves born?
An open cow and a lost calf both cost you a calf to sell. Counting from the females exposed shows both. Nebraska and Texas A&M divide every rate by the females exposed.
Do I take out the cows that died?
No. Nebraska says there should be no change for exposed females that die. They stay in the count.
What is a good calving percentage?
Nebraska says the goal should be 90% or higher.
What is a good weaning percentage?
The CHAPS herds weaned 91.4%, says Wisconsin Extension.
Sources
- Nebraska Extension G2094, Standardized Calculation and Interpretation of Basic Cow Herd Performance MeasuresOct 2022The formulas, all over the females exposed; a calving goal of 90% or higher
- Texas A&M, SPA Cow-Calf Reproduction PerformanceOct 2014Pregnancy rate two ways: of the females exposed, or of those tested
- University of Wisconsin-Madison Extension, Defining success for reproductive and calf crop performanceApr 2025A worked example, 40 of 50 is 80%, and the 91.4% CHAPS benchmark