Most of our autumn calving herds start mating in May – there are a few challenges your cows can face that can make getting them in-calf a bit more difficult. So, if you haven’t done your free pre-mating consult with your vet, then it’s not too late to sit down and discuss how you’re going to deal with the challenges of winter mating!

Some of the factors that can make an impact are –

• A shorter mating length.
  With a shorter mating period there’s more risk; so, everyone needs to be 100% focused to maximise in-calf rates.
• The bulls not playing ball.
  Many of our autumn herds use all bulls, and while you might think that should make mating a breeze – the bulls have a tough time in May and June just as much as cows do! They have sore wet feet, sudden dietary changes, spend a lot of time on concrete, you’ll often have older bulls that have been used before (so it’s heavy 3-year-olds, not spritely 2-year-olds), a shorter day length meaning less time to ‘see on-heat cows’, and of course, there will be 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.
• Tracking heat detection.
  Heat detection is potentially harder in winter as the days are getting shorter not longer. The weather is often unfavourable for cows’ showing signs of heat let alone you doing paddock checks too. Cows are often spending a long period of time off-pasture and on concrete instead – which isn’t a good place to show signs of heat. The cows to be mated in autumn are only a small number of cows, so the sexually active groups are smaller.  This all means you’ll have to work smarter by: use more heat detection aids, ensure you’re touching up tail paint regularly, do more frequent paddock checks, and maybe do less artificial breeding (AB) by swapping to natural mating earlier than you intended (but check that your bull power is adequate for this); consider intervention with non-cyclers too – as late calving autumn cows won’t be producing at peak next season when the premium starts.
• Feeding during mating.
  So far, feeding during early lactation has been a real challenge for autumn calving cows. Their diets have been almost 100% supplement and not well-balanced, so many cows will have lost more body condition scores (BCS) than you’d have expected for autumn cows. Just like spring cows, any cows losing more than 1 BCS between calving and mating are at risk of a 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.
  It’s not too late to get one of our accredited vets to score your autumn cows individually to identify cows that’ll need an extra hand going into mating.  Intervention could include changes in diet, changes in milking frequency, or early non-cycling intervention for this at-risk group.
  It’s difficult to monitor your bulk tank parameters to check in on nutrition of the herd when you’re a split-calving herd as the spring cows will be contributing to the bulk tank. But once they’re all dried off, keep an eye on your bulk tank protein test as it’s a good indicator of energy balance; as we come off-peak milk, a climbing protein test indicates the cows are increasing energy balance. There’s good evidence that associates a higher milk protein test with a better reproductive performance both within herds and between herds. This will give you a clue to whether 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.
• Use the technology available.
  If you’re using technology e.g., collars, tags, or boluses to monitor cow health and activity then the data gained can be a very a valuable source of information to help time AB to each individual cow’s cycle.  Additionally, any information about non-cyclers or irregular heats e.g., short or long returns, can help to improve reproduction results.  Plus, remember that the signs that the technology uses to ID cows on heat (e.g., increased walking, reduced rumination, and change in cow temperature) may be influenced by the challenges that affect traditional heat detection methods as well – e.g., reduced time on pasture, increased time on concrete, feeding changes, mob changes etc., so interpreting this needs the same amount of attention to details as you’d monitor tail paint.  If you don’t know how to interpret this data, then our vets can help you to get the most out of your technology investment.

If you have autumn calving cows and would like some advice, contact your local Anexa clinic.  Our vets are also InCalf Advisors, with a sound knowledge in reproduction, so they’re ready to work with you to come up with the solutions that work for your farm.