I like to think of weaning as the biggest pressure valve in our production system. In our herd, weaning (ending lactation) alone drops our stocking rate by nearly 25%! (26 DSE to 20 DSE per cow/calf unit). Our stocking rate drops even more when you factor in the PTE females that are sold at this time.
Since changing to Spring Calving in 2008, we haven’t had to wean early until this year.
Typically, we wean at 6-7 months or when the calf drop is at an average age of 200 days. The latest we go (following a good spring and then an early autumn break) is 90 days prior to calving (Early May).
Advocates of Spring calving would point out that we should wean earlier because lactation is an in-efficient use of grass. But the least possible feeding and fodder conservation in our system the better. Also, our cows would get too fat by the end of winter!
Last year (2015) we had a very weak Spring which cut out early. Consequently we have less dry standing feed than normal for us and will have insufficient feed for lactating cows by the end of January. Already we can see the second calvers dropping back to a condition score of 3.
We combine weaning and preg-testing in the one yarding. Ultra-sound preg-testers are able to test from 4 weeks so we can go anytime after the 8th January. This year we’ll wean at the end of January when calves will be 4.5 to 6 months old.
So what’s the impact? We feed our weaners for about a month after weaning regardless of the season so the only difference is the duration. We feed until an Autumn break puts enough green feed back in the paddocks. Consequently we have to buy in extra feed when weaning is brought forward.
Feeding young weaners
We feed-test our own silage to know that we are meeting the calves nutritional needs for energy and protein in a ration that they can physically consume.
To grow at 0.5kg/day, 150kg calves need 8.7 ME MJ/kg DM from a ration containing 12% crude protein that is not more than 4.3kg DM/day.
When considering what sort of additional fodder to buy, our choice is between a ration of pellets with hay, or straight lucerne hay which is grown locally by many of the former tobacco growers. This year we are going with the lucerne hay. Feed testing the lucerne hay is essential to make sure it has the expected energy requirements. The two fodder options cost about the same to us but the pellet+hay ration requires twice as much labour every day. We’d also have to invest in a blower pipe for the old silo, a pellet hopper for the tractor or ute and 75m of troughs.
The Cost of Early weaning
Early weaning in a Spring calving system provides excellent drought mitigation because feeding calves is a much lesser cost than feeding lactating cows.
The Evergraze Feed Budget and Rotation Planner (linked to below) includes a useful calculator to evaluate different fodder rations. It tells me that my ration ticks the boxes for energy and protein within the DM consumption limitations and that they will gain 498 grams/day. It also tells me to feed 320 calves will cost $11,500 per month. Not a paltry sum! However, when I consider it is only $36/head/month or $2.41 per kg of live weight gained, I can see the profitability of holding onto our valuable steers and future breeders, even if we have to feed them for are few months.
The extra expense arrives after our biggest revenue inflow (sale of feeder steers) so cashflow is not an issue. Our future cashflow is not interrupted as I’ll have the next line of steers and surplus heifers to sell. And we hold on to our better genetics in our young future breeders.
Further Reading and Resources
Drought Feeding and Management of Beef Cattle. is a great booklet with a wealth of information about managing beef cattle in tough conditions including early weaning.
I use the Evergraze Feed Budget and Rotation Planner to evaluate my supplementary fodder rations.