Monitoring Pre-Cut NDF Development
This will be the last update to the NDF tracker for 2019 (31/5/19). The most recent data will now include an increasing proportion of second cut samples, which may explain the reduction in the average sample NDF content to 39.0%. As we move later into the season the NDF threshold of 38-40% indicated for first cut may not be appropriate for later cuts, requiring further data analysis.
This graph tracks the average NDF development in samples processed through the Trouw Nutrition GB laboratory leading up to 1st cut. This is a national average and it is important to monitor the situation on individual farms through pre-cut grass testing.
Forage forms over 50% of the DMI for a typical dairy cow and can be more in other enterprises such as suckler herds. It is therefore very important that quality and quantity are optimised to suit the individual system.
Grass silage quality is impacted by:
- Cutting date
- NDF content (depending on cut number)
- Sugars and free nitrate
- The silage making process (wilting, clamp filling, rolling, sheeting)
NDF development of the grass crop offers a scientific basis to help optimise silage quality by informing 1st cut mowing decisions. To optimise 1st cut silage quality it is recommended to cut before the NDF content in pre-cut grass reaches 40%. To achieve this we recommend testing pre-cut grass (1st cut) weekly from mid April to monitor NDF development and also provide information on sugar and free nitrate levels which are important in achieving a quality silage fermentation.
Pre-Cut Sample Tests
Take a representative Pre-Cut fresh grass sample that comprises of 10 sub-samples taken in an 'X' pattern across the area (two samples at each point on the 'X'). These should be cut with scissors at mower height and then placed into a sample bag.
Clearly label the sample bag with the customer name and sample reference, and complete a forage sample request form including:
- Your contact details
- The full address for the farm including county
- The sample reference
- Tick the Pre-Cut grass testing box
Post the sample as soon as possible to the Trouw Nutrition GB laboratory.
N.B. Avoid sending samples on a Friday to avoid delays in the analysis if the sample is received over a weekend.
What is GrassWatch?
GrassWatch is the weekly report compiled from Milk Yield from Grazing (MYFG) samples analysed through the Trouw Nutrition GB laboratory each week. The report includes information on grass growth data, grass quality, performance indicators and growing cattle, enabling advisors to discuss approaches to optimise health and performance.
Milk Yield from Grazing
In order to allow feed advisers and farmers to estimate the potential milk yield from grazing relevant to a specific farm, Trouw Nutrition GB has developed the Milk Yield From Grazing app.
Using average grass growth and quality data from the Trouw Nutrition GB laboratory the app allows quick calculation of the potential Milk Yield From Grazing and also gives guidance on the level of supplementary feeding needed to achieve the target milk yield.
Download the app:
- +44 (0)1335 341203
- +44 (0)7850 605 309
- Georgina Thomas
- + 44 (0) 1335 340054
- + 44 (0) 7720 739897
- Dr Elizabeth Homer
- + 44 (0)1335 341155
- + 44 (0)7881 916362
- Rosie Miller
- +44 (0)1335 341152
- +44 (0)7701 384158
- Dr Laura Tennant
- 01335 342217
- 07936 342423
- Laura Drury
- +44 (0)1335 341205
- +44 (0)7917 277466
- Tom Goatman