Firstly, let’s remember that these calves have a short window of time before they will be joining the herd as milking cows. 79% of heifers in NZ don’t make it to target calving liveweights and their liveweight when they head off to grazing is related to their growth rates while at grazing so it is important that we get this first part right.
Calves are born with an undeveloped rumen and we need to ensure their rumen is large enough and functional before milk is removed from their diet. Provide meal from one week of age to get this process underway early and ensure this meal contains the right ingredients (amino acids, starch and buffers) to drive this process efficiently and safely.
Check that calves are eating at least 1kg meal each a day (how much meal are you feeding to the group? Are all calves eating it?) before considering weaning and use scales rather than the eye-o-meter to determine when they have reached the weaning target you have set (typically 80-100kg). Even those regularly weighing large numbers of calves will have a large range when guesstimating weights. The timing typically coincides around when calves will be needing to be yarded for a second clostridial vaccination and drench so allow a bit more time for weighing.
Once weaned from milk, continue meal feeding until calves are at least 120 kg (again using scales) as rumen development doesn’t stop just because they are no longer drinking milk – in fact, it continues until calves are 150 kg.
From then on, regularly 4-6 weekly weighing alongside your other animal health treatments is important to allow early identification of drops in growth rates. If you don’t have scales or the time, our technician team are able to provide weighing and animal health services customised specifically to your farm’s needs.
Contact your local clinic for more information on Nourish calf meal and our heifer health and weighing services.
Dr Ilyse Jennens BVSc (Dist) MANZCVS Medicine of Dairy Cattle – Branch Manager at Franklin Vets Waitakaruru