If you’re recording data for BREEDPLAN, one of the most valuable pieces of information you can collect is birthweight.
But not all birthweights are created equal!
What to use:• Actual birthweights should be taken as soon as practical after birth.
• Weights collected using scales (crate scales, hanging scales, platform scales, calf weigh systems, etc.).
• Measurements recorded consistently across your calf crop.
• Birthweights from all calves where possible, including stillborn calves.
What not to use:• Estimated weights. e.g. “He looked about 40kg” guesses.
• Weights taken days or weeks after birth and entered as birthweights.
• Different methods for different calves within the same contemporary group.
• Weigh tapes or girth tapes used to estimate birthweight.
Why not weigh tapes? Research has shown that weigh tapes and girth measurements can be highly unreliable for newborn calves. Factors such as calf shape, breed, muscling, gut fill, and how the tape is positioned can all influence the result. While they may provide a rough estimate, they do not offer the level of accuracy needed for genetic evaluation and should not be used as a substitute for an actual scale weight.
When should you weigh them? The closer to birth, the better. Ideally within the first 24 hours, before significant growth occurs.
Why does it matter? Birthweight is one of the key traits used in BREEDPLAN to help estimate:• Calving Ease
• Birth Weight EBVs
• Genetic trends within your herd
• The performance of individual sires and cow families
Importantly, recording all calves gives BREEDPLAN the complete picture. Leaving out difficult births, heavy calves, or stillbirths can unintentionally bias your data. Including stillborn calves and their birthweights helps improve the accuracy of genetic evaluations, particularly for birth weight and calving ease traits.
Accurate birthweight records help improve the quality of your herd’s genetic information, giving you and future buyers greater confidence in your EBVs.
Remember: A guessed or estimated weight is often worse than no weight at all. If you can’t collect an accurate scale weight, it’s better to leave the record out than introduce unreliable data into your herd’s genetic evaluation.