This is a very busy time of the year! Mating and AB are starting, crops are going in, and silage is being cut. At the same time we often have lingering spring weather and animal health issues. But, among all of this chaos, you can’t afford to forget your youngstock!
Calves – how do you wean your calves?
Hopefully they are weaned in batches, but how do you pick those batches? You can choose calves based on age, but not all calves are ready at the same time. Commonly suggested weight targets for weaning are 70kg for Jerseys, 80kg for Fr x J Crossbreds, and 90kg for Friesians, with many suggesting these are minimums. If you don’t have scales, pick up a weigh tape at your local Anexa clinic. The other factor to use when deciding who to wean is the “rumen score”. Calves with well developed rumens are not ‘slab-sided’, but instead have a well rounded rumen visible on the left side of the body. You can also use consumption as a weaning tool- calves eating more than 1kg/day can be weaned – but this means the average mob intake needs to be about 1.3-1.4kg/day over a few days to ensure that ALL animals are eating more than 1kg.
Don’t wean too early!
It is very tempting to stop feeding calves during this busy time by weaning late calves a bit early. DON’T DO IT! These late calves are already a few steps behind their earlier mates – weaning them early will set them back even more! Late calves should actually be weaned later/heavier than early calves. For more detailed information on weaning decisions see DairyNZ’s info sheet here: http://bit.ly/WeaningDecisions
Heifers – mating weights should not be a mystery!
Weigh your heifers! Heifers should be 60% of mature weight at mating. Pre-mating weigh in (or even during mating!) is also a good time to talk to your vet about trace element supplementation. We are seeing a lot of youngstock deficient in Selenium and Copper. Don’t be disappointed with your heifers at calving – go weigh them now, while there is still time to do something about it.