Grass tetany: With temperatures dropping, heavy showers and a recent surge in growth, grass tetany has been an issue on some farms over the last few days. Grass tetany, or hypomagnesaemia, is caused by a deficiency of magnesium (Mg) in the blood. Sucklers don’t have much ability to store Mg in their bodies and need a daily supply to prevent deficiency. It is common with suckler cows when they are grazing very bare, as well as lush pastures. This grass is frequently low in Mg due to quick growth and heavy slurry spreading, which is high in potassium and can have a negative effect on Mg uptake. It can be associated with stress like transport, wet weather, cows in heat or changes in diet or pasture. Ways of controlling or preventing grass tetany include:

  • Feeding high-Mg concentrates.
  • The addition of Mg to the drinking water (this can be questionable in periods of wet weather).
  • Buffer feeding with hay or straw.
  • Giving free access to high-Mg minerals, either by way of powder mineral or mineral licks.
  • The use of Mg bullets — at least two bullets/boluses should be used per cow which will release Mg at a controlled rate each day for four to six weeks.

    • BDGP update: Participants in the programme using a stock bull were required to have at least one bull on their holding on 30 June 2020 who was a minimum of 12 months old and was rated at four or five stars on the replacement and/or terminal index, within and/or across breed on the first genomic evaluation or the genomic evaluation at the time of purchase. There have been two simpifications:

  • 1 Some bulls’ genomic evaluations are under way and more tissue samples may be sent to the ICBF this month. The next rounds of genomic evaluations will be published on 21 July and 22 September. If you send samples before 8 July and your bull is confirmed to be four- or five-star in either of those rounds, he will be eligible.
  • 2 Where a bull or heifer on the holding had a published genomic evaluation and had been deemed ineligible as it was rated at three stars or less on that first evaluation, it can now be deemed eligible if the bull or heifer is now rated at four or five stars.

    • If a herd fails the stock bull requirement, 10% of the 2020 BDGP payment will be cut. The ICBF has advised scheme participants to check their herd’s compliance by logging into their ICBF HerdPlus account. Once logged in, go to the “View Profiles” dropdown and select “BDGP Eligibility”. If your herd is non-compliant on any breeding requirements, it will be highlighted by an X in a red box. If you do not have access to a computer, you can call the ICBF on 023-883 288.

    For the 31 October deadline, you need to have 50% of your reference number of breeding animals genotyped four- or five-star on the replacement index. For animals to be included in the final evaluation run on 22 September, they need to have their genotype tags returned by Wednesday 8 July. Make sure you have enough animals to meet the requirements of the scheme.