THE analysis of 150 first cut silage samples taken in late April to mid-May indicate the need for farmers to focus on managing rumen pH and providing adequate amounts of structural fibre in the ration.
The early silage results show good levels of energy and protein which means cows will milk well explains Robin Hawkey, Mole Valley Farmers, however results for structural fibre are lower than expected, this combined with a high acid content could have an impact on milk constituents unless they are managed correctly.
Dr Hawkey says: “Although neutral detergent fibre (NDF) and acid detergent fibre (ADF) are similar to last year, the lignin value is lower. The reduced structural fibre may have implications for rumen stability.
“This suggests rations will need to be balanced with adequate structural fibre such as wholecrop wheat or barley or straw in order to promote rumen health.”
According to the results, lactic acid levels are up compared with last year, from 57g/kg dry matter (DM) to 79g/kg DM however acetic and butyric acid levels are lower.
Dr Hawkey explains this is great news for the promotion of stable fermentation in the clamp, however it will add to the challenges of balancing rumen pH.
Lactic acid levels are likely to increase during the time the silage is ensiled, so Dr Hawkey urges farmers to test their silage regularly throughout the season to gain an accurate picture.
There are also reports of reduced levels of crude protein in fresh grass samples which may have a knock-on effect on silage in the clamp. The lower protein levels may need there is a requirement for supplementation with a higher 18 per cent protein cake.
While there are some challenges indicated by the early analysis, the generally high quality will promote high intakes, which may cause forage stocks to be even tighter than expected over the winter. Dr Hawkley suggests extending existing stocks with moist feeds such as brewer’s grains, fodder beet or potatoes.