Collecting birthweights on calves at Gyranda for over 10 years

on 4th September 2023

It’s always exciting when calves start hitting the ground – to not just see the genetics and test the metal of a new generation of calf catchers. It also signals the shift in focus that’s about to take place from bull selling to cow-calf nutrition and closer pasture monitoring.

Birthweight remains in if the more difficult and more expensive traits to gather information for.

So what does it take and why do we do it?

Firstly, we have certainly seen the benefits of doing so in our own herd. Identifying low birthweight, high growth genetics minimises risk to heifers while maximising the potential for progressing the entire herd forward at a faster rate.   Your newest cutting edge genetics should technically be in your younger generation cattle.  Three of seven sires retained in the herd this year are out of first calf heifers.

Essentially we bring the maiden heifers in closer to the homestead just before they are due to start calving for ease of access.  Each morning a crew of two or three head out to check if anything has calved overnight.  While the favourite ones to catch, weigh, tag and release are those who are lying peacefully on the ground and happy to stay there but some of these calves are feisty fellows and are up for a solid run.  It can be excellent  exercise and team work training for the whole crew and the job is not done until calf and mother a happily back together grazing and sucking contentedly.  The heifers generally are cautious and curious which makes life a little easier on the humans.

Over the past ten years we have tried a few different strategies and honed our technique.  We have at times married the process with pelvic area measuring and even participated in a walk-over-weigh (w-o-w) trial which aimed to estimate calf birthdate and mothering up through algorithms and cow-calf association over the scales.  Thanks to COVID-19 and equipment failure the w-o-w trial was abandoned but we learned a lot along the way.

We also endeavour to weigh what calves we can out of the mature herds but those cows are a bit more clued in and far more protective of their babies.  We live in dingo country and they’ve got the gist of what their role is as mothers by their second go around.  Margo Sullivan from Mataranka, NT was determined 300 calves would be weighed the year she was here on her Marcus Oldham prac year.  in pursuit of this goal, we found ourselves out morning and afternoon, alternating paddocks, hiding behind trees or troughs, taking refuge in the buggy and on one occasion out of our depth in the river.  Margo came pretty close to her goal and we achieved a good cross reference across all joining groups which set us up well for EBV accuracies.  Another year, both the buggy and the team broke down and we only managed a dismal 30 or so of our first calf heifers.

You can find a full collection of videos on our Gyranda Youtube channel.  Those on calf birthweights can be found below.