Dairy farmers are warned of risk of spoilage to this year’s crop if aftermaths are not removed from fields.
Dairy farmers are being advised to remove aftermath from silage fields or run the risk of significant aerobic spoilage in the conserved forage they make this year.
Dr David Davies, director of independent forage consultant Silage Solutions, says: “The winter has been extremely mild and grass has just kept growing.
“Last December was the warmest since records began in 1910, with an average temperature of 7.9degC. It was also the wettest month in the UK for more than a century.
As a result, there is a lot of grass aftermath about, but plenty of wet, dead material is caught up with it too which is likely to contain high levels of yeast and fungi.
More rainfall over the next few weeks will only increase soil splash up to leaves, increasing the level of undesirable microbes still further.
“The threat of mould growth in forage clamps and other stored feeds and the associated mycotoxin production will only get worse if mild temperatures and significant rainfall continue to the end of the winter.”
Dr Davies advises farmers to remove the aftermath if possible. He says: “Many dairy farmers do not like taking sheep on tack, but they are the best animals for cleaning the sward in winter.
“There are two options: either leave the aftermath, which means you run the risk of producing poor quality silage; or you remove it by mowing it off, wasting it, or bringing sheep in.”
If neither option is practical, Dr Davies says many farmers will have to focus on excellent clamp management this year.
Emma Millar, mycotoxin management specialist at Alltech UK, says compaction of grass in the clamp is absolutely critical. She says: “When clamping silage to reduce the risk of spoilage and potential mycotoxin contamination, the aim is to remove as much air from grass as quickly as possible.
“Fill the clamp in layers no more than 15cm deep at a time and compact as you go. Your target should be 750kg of fresh material per cubic metre.
“Most farms are only reaching 650kg per cu.m or less, which means too much oxygen is left with the grass, increasing the chance of aerobic spoilage and moulds, and then potential mycotoxin contamination.”
Dr Davies advises farmers with a lot of aftermath who are concerned about spoilage to use an appropriate silage additive.
He says: “Ideally, use a homo-fermentative inoculant plus a chemical additive, or a chemical [salt] alone. The inoculant will improve fermentation and the salt reduces aerobic spoilage. This will help stabilise the clamp.”