Management hint: How to avoid stress at weaning
Poor conception rates in replacement heifers are often due to heifers being underweight by the start of the breeding season.
The task of achieving this target pre-breeding weight begins once a replacement heifer is born, until mating start date (MSD) when she reaches approximately 13 to 15 months-of-age.
As the future replacement heifers approach the stage of weaning, we must ensure that an adequate weaning plan is in place – to minimise any stress placed on the calves – as they make the switch from whole milk or milk replacer to solid feed.
Poor management of calves pre and post-weaning can result in poor potential growth rates, health issues and failure to reach heifer rearing weight targets.
- Calves should not be weaned until they are continually eating 1kg of concentrates per day;
- Weigh regularly to monitor weights: Holstein-Friesian calves should be at least 100kg at weaning and Jersey-cross calves should be at least 80-85kg at weaning;
- Underweight calves should be grouped together and continue being fed milk or milk replacer until target weights are achieved;
- When weaning, the volume of milk should be decreased gradually over the course of a few days.
- Calves should be grazed in a leader-follower system of grazing – ahead of older cows;
- They should be moved regularly to ensure they have continuous access to fresh grass;
- Concentrates should continue to be fed (1-2kg/calf) until grass intakes increase.
Furthermore, once the calves are weaned and at grass, it is important that a consistent worming programme is put in place.