Feel like your work’s finished with your heifer calves? Not just yet…
Poor fertility in replacement heifer calves is often due to them being under target weight by mating start date (MSD). This can be avoided if good management practices are implemented all the way along the heifer rearing process.
By now, you should have a good chunk of your calves weaned and the majority, if not all, should be out at grass.
Often, the calves can be forgotten about this time of year because once they go out to grass, you feel like all the hard work is done.
The vast majority is – but good management now will ensure that all your replacement heifers reach their six-month target weight (30% of mature body weight) and reach it together.
- Graze in a leader-follower system ahead of older animals;
- Offer fresh grass regularly;
- Continue to feed 1-2kg of concentrates for 4-6 weeks post-weaning;
- Monitor weights regularly and group calves according to size;
- Dung sample for worms and dose accordingly.
Leaving calves in a designated calf paddock this late in the season is not advisable. They should have access to fresh grass and should be moving regularly because they are selective grazers.
If calves are left in a paddock for a long period of time – ahead of older animals – they can ‘sour the grass’ and leave a high amount of unpalatable grass for the following animals.
Before jumping in and dosing all the calves, take a dung sample. This will allow you to identify which parasite is causing the infection, so that you’re not wasting money targeting the wrong one.
Finally, when taking a dung sample, take a small amount (quarter of a teaspoon) of dung from a number of dung patches to get a representative sample.