May Focus
May 2024

Hi Everyone,

What a lovely autumn we’re having – it’s such a pleasure after lots of droughts in recent years.

We’re seeing a few cases of facial eczema around the place, unfortunately it takes more than a few chilly nights to destroy all those spores. Some herds have blood tested all their cows as part of a particularly cool trial with LIC looking at inherited resistance to facial eczema, and we’ve been horrified at the number of perfectly healthy-looking cows with blood results showing they’ve been badly hit. No wonder that often cows don’t milk, and young animals don’t grow as well as we think they should at this time of year, even when they’re being really well fed.

Below is our mid-month dairy vet e-Update for May:


  • Drying off time for most. Remember to reduce milk production in the week leading up, by restricting ME and reducing protein in the diet. The link below is to a short video on Facebook – super practical drying off tips. Facebook Link - click here
  • Plan your dry off day – pick good weather, have a clean paddock for them to go to, and ensure as many staff as possible are present to help so cows aren’t standing around too long after milking.
  • Practice excellent hygiene - Clean your teat ends well, keep your hands clean between cows, insert the tube tip carefully and hygienically, and teat spray afterwards at the maximum label strength. If you haven’t already done so, watch the Teatseal Best Practice video at to ensure everyone helping the dry off knows the expected standards.
  • Down cows – We’ve seen a few cases of milk fever, thanks to lots of zinc and lots of maize being fed to cows. Adding lime flour to the maize is always a really good idea at this time of year.
  • Winter milkers need to watch the SCC – milk those high SCC empties last to not spread the bugs.
  • Herd vaccinations should be planned now the heifers are home – Lepto, Salmonella, Rotavirus. We’re rolling out the new lepto 4-way vaccine this season – it gives extra protection against the lepto strains commonly spread by rats, which are responsible for more and more of the cases of human lepto seen in NewZealand.
  • Now is a good time to start thinking about your risk of nitrate toxicity and how to mitigate the risk. Drought conditions are a risk factor as plants under stress accumulate nitrate. Other risk factors include new grasses or cereal crops, and cool cloudy or foggy days. Affected cows are often found down or staggering, with distinctive brown mucous membranes. This is an emergency. On-farm nitrate tests for pasture and crops are available.


  • Most are arriving home, if not home already. Settling them and using the time to train them to the shed will pay dividends in the spring.
  • Heifer teatsealing is underway, please help us help you by: having the hot water turned on, having as many staff as possible on hand to help during the job – for both our and the heifers’ safety, making sure the heifers are fed a high dry matter feed in the 48 hours before – hay/straw/dry grass silage – to firm the faeces and improve hygiene, and have a clean paddock for them to go to. There is always the risk that some get mastitis afterwards, but the more you can do to help the job go well, the better we can perform.
  • Boost their vaccinations as required, in particular Lepto & Rotavirus.


  • Now is the time to ensure trace minerals are supplemented going into winter and after a long zinc season – Copper, B12 & Selenium are all essential for good growth rates.
  • With the warm autumn weather continuing, a high worm burden is likely to carry on, so keep up with the drench interval – commonly 6 weeks between a pour-on/injectable drenches.
  • Keep the feed up throughout winter – a 2 month check in growth rates means later hitting puberty & beginning to cycle, severely impacting their ability to get in calf and thus their future production.

All the best for the rest of May.