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Calf–dam weight ratio

Compute how much of the dam’s body weight the calf represents at weaning — a simple cow-efficiency check used alongside adjusted 205-day weight.

When to use

Use this when you have a calf weaning weight (actual or adjusted 205-day) and a dam weight taken near weaning, and you want the classic percent-of-dam figure for culling or benchmarking.

Many herds target roughly 45–55% of dam weight for weaned calves, but breed, age of dam, and milk level shift the range. Pair with the 205-day tool when ages differ widely.

Calculator

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How this is calculated

Ratio percent is calf weight divided by dam weight, times 100.

ratio% = (calf_lb ÷ dam_lb) × 100

Worked example

Calf weans at 550 lb, dam weighs 1,200 lb near weaning:

Ratio = 550 ÷ 1,200 × 100 = 45.8% of dam weight.

Limits / assumptions

Assumptions: weights share the same shrink basis; dam weight is near weaning.

Limits: not a genetic evaluation; does not replace contemporary-group ratios or EPDs.

Responsibility: verify scale accuracy before ranking cows.

FAQ

Actual weaning weight or 205-day adjusted?

Stay consistent across the herd. Adjusted 205-day is fairer when ages differ; actual weight matches sale day.

What if dam weight is from breeding season?

Prefer a weight closest to weaning. Breeding-season weight is only a rough proxy.

Is higher always better?

Very high ratios can mean a light dam — check dam size and condition before selecting on percent alone.