Maize damage prompts acidosis warning
Some will get up, some won't. Don't use your cows to clean up those paddocks.
Taranaki Veterinary Centre vet Dallas Nelley
Farmers are being warned against letting stock clean up wind-damaged maize crops after some animals developed acidosis.
Ex-cyclone Gita caused considerable damage to maize crops around Taranaki and although farmers may be tempted to let their cows graze those paddocks, the consequences could be fatal, Taranaki Veterinary Centre vet Dallas Nelley said.
‘‘A lot of guys have put their cows in to clean up those paddocks but it hasn’t gone well, the cows end up sitting down with acidosis,’’ he said.
‘‘We’ve got one guy who had over a dozen sit down and and we don’t know how many of them will get up.’’
Acidosis can occur when cows are fed too much starch or sugar, or where the starchy or sugary feed has been introduced too rapidly into the animal’s diet.
Dangerous levels of lactic acid can be produced, causing lethargy, illness and in severe cases, death.
Although some animals would recover with veterinary treatment, others wouldn’t, Nelley said.
‘‘Some will get up, some won’t. Don’t use your cows to clean up those paddocks.’’
In many cases farmers would still be able to salvage their damaged crops, Pioneer regional manager for Taranaki and Rangitikei David McDonald said.
Maize was a reasonably resilient plant, often surviving serious wind events, so it was important to calmly assess and categorise how much of the paddock was affected, and the severity of the damage, before jumping to conclusions, he said.
‘‘Crop growth stage will have an impact on how the crop quality and yield will be affected. Plants affected at later stages of grain filling development may not be affected as much as if it was during early grain filling.’’
Pioneer Taranaki area manager Kim Sharpe said she had seen a varying degree of crop damage across Taranaki farms, but in most cases, time would set right the damage.
‘‘I’ve seen a lot of maize on the ground, but it hasn’t snapped; if stems are bent but upper plants have straightened vertically, plants will likely still be able to transport water and nutrients and should continue to mature, albeit at a slower rate,’’ she said.
‘‘It’s important for farmers to give the crop time to respond and recover, and in most cases it will still go through its process; it just takes time.
‘‘The key thing is acknowledging that every crop is different, and we are ahead of the game this season, which is an advantage.’’
This season’s higher than average temperatures meant most crops had matured early and were nearing harvest time, but McDonald said farmers still had time to harvest crops before they became too dry.
‘‘Talking to your contractor is crucial, as there will be some differences in how they harvest maize that is lying down.
‘‘It is recommended to harvest in the direction going into the crop, or diagonally. Some contractors may have different heads or fronts that more easily pick maize up off the ground.
‘‘A key thing to remember is that the harvesting process is going to be a lot slower than usual: instead of contractors harvesting up to 4ha/hour, some may be limited to harvesting around one hectare per hour.’’
A good quality inoculant would also help with the fermentation process, especially given the likely soil contamination and lower dry matter.
Good stack management with good compaction were even more critical.