News & Advice

Plan and prevent nitrate poisoning

Jun 5, 2020 | Beef cattle, Dry stock, Grazing youngstock

Drought conditions allow build-up of nitrate in and around roots of the plant. When followed by a significant rain event we get a sudden uptake of nutrients and rapid plant growth.

The warm and overcast weather that accompanies these good growing conditions limits photosynthesis, and plants are unable to convert nitrates into protein. Forage crops, especially cereals, and autumn sown new pastures are the top candidates for this phenomenon.
Every year we see the preventable death of animals due to nitrate poisoning.

Risk factors include:

  • Feeding certain feeds such as new grass, brassicas, sorghum, tama and oats;
  • Periods of warm, wet, overcast conditions, especially after a dry spell.


However, with careful planning, you can manage high-risk feeds during this period to prevent nitrate poisoning:

  • DO check nitrate levels of high-risk feed before starting to feed it out
    Nitrate testing kits are available from your nearest clinic
    Collect samples first thing in the morning and bring them into Anexa for testing. Remember to test both the stalk and the leaf, as they can have different levels of nitrate.
  • DO feed alternative feeds such as hay or other grass in the morning
  • DO wait until early afternoon to feed high-risk feed
  • DO NOT feed high-risk feeds first thing in the morning
    Nitrate levels increase overnight so are highest in the morning
    Sunlight helps to reduce nitrate levels during the day
  • DO NOT feed high-risk feeds on an empty stomach
    Concentrated amounts that are quickly eaten are more likely to cause poisoning
  • DO NOT feed high-risk feed for a long period – NO MORE THAN 1.5 to 2 hours!


Most importantly, keep a close eye on stock after feeding high-risk feeds for signs of nitrate poisoning – these are usually apparent within 3 – 4 hours of feeding.

Signs include:
! lethargy,
! rapid and open-mouth breathing
! going down and becoming bloated
! and in worst cases, death.
If you see any of these signs, call your vet IMMEDIATELY.
If treated early, an antidote can be administered to save animals’ lives. However, if left untreated, cows can die very quickly.
For further information, please talk to your Anexa Vet. We can supply nitrate poisoning kits or test samples for you.

Share This