This season, over 1,000 grass silage samples have been analysed by Trouw Nutrition GB Laboratory. This provides an overview of 2021 silage season and how to plan for the coming year. Generally, 2021 silages are low in crude protein, which is not surprising at pre-cut samples which are normally around the 25% CP mark came back 17-20% CP. Some first cuts have been fiery, with low NDF however the majority of samples are higher in NDF and of lower digestibility.
Average grass growth
It has been a strange year consisting of a mild winter where grass continued to grow to periods of rainfall and drought; the met office concluded that this was one of the hottest and wettest April’s with cold temperature at night. Generally, those producers who cut early, had decent cuts with those cutting later having more mature cuts with greater variability.
Comparison between 1st and 2nd cuts
Early 1st cuts show a smaller sample size which indicate that producers cut later, cutting more mature, lower protein 1st cuts. Comparing this to 2nd cuts highlight significant variability; although NDF levels are good, lignin levels increase (table 1).
What this means on farm:
There is massive variability, not only within cuts but within the clamp which highlights the importance of testing forages frequently; at the moment forages are getting tested every 45 days, analyses has shown that the optimal analyses frequency should be 17 days, not only to optimise animal health and performance but also for economics.
Typically, the analyses show that from 1st to 2nd cut:
• Less RFC
• TFC increases
• RFP and TFP decreases
• Only early first cuts are high in fermentable protein
Here are our top 5 tips for feeding silage this season:
1. Frequent analysis is key to making the best use of silage
2. Silages are typically low in protein; what is the best source of supplementation?
3. Consider NDF levels and digestibility
4. Rumen efficiency is key to profitability; ensure balanced and healthy
5. Look out for changes in the cows; what does the dung look like? Are cows ruminating? What about milk constituents?
As with many things, planning is key to optimising performance and although it may seem like a million miles away there are some key pointers to consider for next season’s silage making:
1. Plan ahead
2. Are you monitoring grass growth?
3. Are you monitoring grass analyses and development?
4. What are you trying to achieve? Milk yield, cost efficiency?
5. Analyses forage frequently to account for variation
