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Yearling heifer mating Rebecca Hickson. Outline. Profitability of calving heifers Beef cow efficiency Why calve heifers Why not calve heifers Performance of heifers in industry How to calve heifers. The costs and the income. The 2-year-olds will be there anyway
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Yearling heifer mating Rebecca Hickson
Outline • Profitability of calving heifers • Beefcow efficiency • Why calve heifers • Why not calve heifers • Performance of heifers in industry • How to calve heifers
The costs and the income • The 2-year-olds will be there anyway • How much extra has it cost you to feed them to support pregnancy and lactation? • More calves = more income from the beef herd • What is an extra calf worth?
Example of extra costs • Assume heifers are 346 kg at 15 months (joining), 484 kg at 31 months (weaning) • Calves are 34 kg at birth, 232 kg at weaning at 208 days of age; 6 kg milk/day • Pasture is 11 MJ ME per kg DM • Non pregnant heifer eats 2565 kg DM • Heifer and calf eat 3713 kg DM • An extra 1149 kg DM (45%) over empty heifer • At 12c/kg DM this is an extra $138 in feed eaten
Example of extra income 232 kg weaner at $2.20/kg = $510??
Efficiency (or lack of it) • Beef cows are exceptionally inefficient • 70% of feed requirements are for maintenance • Efficiency depends on • Number of calves weaned • Weight of calves weaned • Feed requirements (live weight) of cows
Increasing efficiency • Smaller cows – breed and EBVs • Bigger calves – breed and EBVs, ‘milky’ cows • More calves • National calving percentage hardly changed in 20 years • Getting calves from the 2-year-old heifers increases number of calves far more than any tweaking of calving percentage of mature cows
Why calve 2-year-olds? Survey of 331 farmers in charge of 16,000 heifers
Simulated profitability and dystocia • Based on a simulated farm with a fixed feed supply, and assuming an assisted birth killed 36% of calves and 11% of heifers… • More profitable to calve 2yo heifers than 3yo heifers as long as incidence of assistance remained below 89%
Industry performance of 2yo heifers • 86% pregnant per heifer joined • 78% calves marked per heifer joined • 9.6% heifers assisted at calving • Of 386 assisted births: • 36% of calves died • 11% of heifers died • 84% of heifers that calved at 2 calved again at 3 • 7% were empty, 9% culled for other reasons or died
Get heifers ready for joining • Well grown • Reach puberty (mean live weight 297 kg for Angus heifers) • Get a ‘head start’ on the calf – reduce dystocia
Choosing the right bulls • All about the EBVs! • Direct calving ease (higher is better) • Birth weight • Accuracy: is birth weight measured in the herd you are buying from? Do they calve their 2 year olds? • Shape is of little (no?) importance, just birth weight • Daughters’ calving ease EBV useful if choosing a bull to father your replacements
Feeding during pregnancy • Feeding in early pregnancy does not affect dystocia • Losing 560 g/d from 6-12w of gestation reduced milk production • Feeding in late pregnancy does not affect dystocia reliably • Underfeeding can reduce milk yield, calf weight and pregnancy rate to rebreeding • Keep them within the range of ‘normal’, neither very thin or very fat
Management at calving • Where do you calve them? • How often do you observe them? • At what point do you assist?
Rebreeding & culling • Cull heifers that don’t get pregnant at 15 months • Dystocia at first calving does not imply future dystocia • Rebreeding at 2 not a big problem (?)
Try it! But choose your bull wisely Thanks to Beef + Lamb NZ for funding the research underpinning this talk