Silage analysis vital to maintain diet quality
A wide range of analyses of first- and second-cut grass silages makes it vital dairy farmers get clamps analysed soon.
Adam Clay, ruminant manager for Frank Wright Trouw Nutrition International, says while results from 2,000 first-cut silages and over 300 second-cut samples look encouraging, the range shows fine tuning will be required to maximise use from forage this winter.
Compared with last year, this year’s first cut is slightly drier, with marginally higher D values, ME and crude protein levels.
“Overall first-cut silages look to be well made and should support high forage intakes combined with better rumen health,” says Mr Clay.
Initial second-cut samples are dry, and although not poor quality, are not as high in energy as might be expected. “However, NDF levels are high and suggest this year’s second cuts will provide useful structural and nutritional fibre to improve rumen health and function,” he says.
However, he warns that average analyses are no more than a useful overall guide to harvest quality and certainly no substitute for getting actual crops analysed.
“This year 54.4% of silages analysed had an ME higher than the average figure, and while only 45.6% had a lower ME, some of the lower figures were extremely low,” he says.
Overall 63% of the crops were within 0.5MJ ME of the average, but the lowest 10% are over 1MJ/kgDM lower.
Results also showed a significant range in dry matters which will affect the total nutrients available.
“Drier crops will be more prone to sorting increasing the risk of acidosis while with the wettest silages it may prove impossible to achieve high levels of intake, increasing the requirement for supplementation. Both will present challenges with diet formulation.”
Mr Clay urges farmers to get all grass silage analysed quickly to understand the basis of diets this winter and to give more time to source the most effective supplements.
“For many farmers the prospects for this winter should be encouraging provided they ensure the diets are designed to optimise rumen performance and make the most of their silages.”