With most of our autumn calving herds starting mating in May, there are a number of challenges your cows face that make getting them in calf a bit more difficult. If you haven’t done your free Pre-mating consult with your vet, it’s not too late to sit down and discuss how you are going to deal with the challenges of winter mating! 

Shorter mating lengths 

With a shorter mating period there is more risk; everyone needs to be 100% focused to maximise incalf rates. 

Bulls 

Many of our autumn herds use all bulls, so might think mating should be a breeze – but bulls have a tough time in May and June just as much as cows do! Sore wet feet, sudden dietary changes, lots of time on concrete, often older bulls that have been used before (heavy 3-year-olds, not spritely 2-year-olds), shorter day length meaning less time to ‘see on-heat cows’ and of course bad weather days where even the bulls just want to stand in the corner with their bums to the wind and rain.

Therefore, bull management for winter mating needs a concerted effort from the whole farm team, to ensure the bulls are at optimal performance every day. 

Heat detection 

Heat detection is potentially harder in winter. The days are getting shorter not longer. The weather is often unfavourable for cows showing signs of heat let alone you doing paddock checks. Cows are often spending a long period of time off pasture on concrete, which is not a good place to show signs of heat. Often the cows to be mated in the autumn are only a small number of cows, which means the sexually active groups are small. So all this just means you have to work smarter – use more heat detection aids, ensure you are touching up tail paint very regularly, do more frequent paddock checks, maybe do less AB and swap to natural mating earlier than you intended (but check that your bull power is adequate for this), consider intervention with non-cyclers as late calving autumn cows won’t be producing at peak next season when the premium starts. 

Feeding during mating 

Feeding during early lactation has been a real challenge for autumn-calving cows so far. The diets have been almost 100% supplement and not well-balanced. This means that many cows will have lost more BCS than you would have expected for autumn cows. Just like spring cows, any cows losing more than 1 BCS between calving and mating are at risk of poorer reproductive performance, therefore having a plan for identifying these high-risk animals and feeding them preferentially during mating is crucial to getting them back in calf.

Monitoring your bulk tank parameters to check in on nutrition of the herd is difficult when you are a split-calving herd as the spring cows will be contributing to the bulk tank of course. But once they are all dried off, keep an eye on your bulk tank protein test as it is a good indicator of energy balance; as we come off-peak milk a climbing protein test indicates the cows are in increasing energy balance. There is good evidence that associates higher milk protein test with better reproductive performance both within herds and between herds. This will give you a clue if you need to be increasing the energy density of the diet to counteract adverse weather, which will help to flatten out not only your production curve (and gain those precious high-value milk solids) but also your protein test and therefore sustain your submission and conception rates through these climatic conditions.

If you have autumn calving cows and would like some advice, contact your local Anexa Vet clinic, many of our Vets are also InCalf Advisors, with a sound knowledge in reproduction they are ready to work with you, to come up with the solutions that work for your farm