Nitrate poisoning is caused by high nitrate levels in feed and usually occurs in late autumn or winter, particularly during a flush of growth after a dry period.
In an email to Waikato farmers, DairyNZ regional leader Waikato Wilma Foster outlined key factors to reduce of nitrate poisoning in herds.
• Test grass for nitrate levels – you can get kits from your local vet clinic. Test each break.
• Feed supplement first before feeding high nitrate feeds – this reduces the eating speed of cows.
• Feed ‘at risk’ pastures/crops in the afternoon on a sunny day – sunshine helps break down the nitrate levels, avoid these paddocks on cloudy days.
• Check the animals 1-2 hours after you put them on a new break.
• Call a veterinarian at the first signs of trouble.
