Silage analysis from our last field trip in Feb 2018. I have highlighted important terms for LC Ag Science below.
Overview
Preparation
Field reseeded in July 2015 with Perennial Ryegrass/Clover mix.
Field closed 7 weeks prior to harvesting after grazing ewes with lambs
Fertiliser application - 2 bags of 18-6-12 per acre and 1 bag of Nitrogen
Harvesting
Harvested on 2nd June 2017
Cut in morning and baled that afternoon as rain was forecast the following day.
DMD (Dry Matter Digestibility) - 72.2
is an accurate and reliable test of the feeding value of this silage.
DMDs of 70% and over are good and we are quite happy with the this result.
The DMD result is used to estimate energy of the silage, as well as expected live weight gains/milk yields and planning supplementation rates.
Metabolisable Energy (ME) -10.8
Measures the usable energy of the silage which is higher at the young leafy grass stage and lower at the hay stage.
Our value is good but could be improved by cutting the grass earlier when it is more leafy. This would however reduce the number of bales.
pH - 3.97
pH, normally 3.8 to 4.2, measures the silage acidity and so the ability of the silage to store. Reduced intakes can occur with too low a pH while a high pH in low dry matter silages can be an indicator of poor fermentation. .
Crude Protein- 12.5
Levels are a direct reflection of the quality of the grass at the time of harvest. Young leafy grass produces high protein silage while older stemmy grass produces low protein silage. Protein levels in grass can also be much higher earlier in the silage season than in mid-summer.
Dry matter (DM %) -20.9
This is the amount of silage material after water has been removed. Generally the higher the dry matter the higher the potential intake of silage. However silages that are too dry can give rise to moulds and heating.
We would not be overly happy with this as ideally we would like the DM to be +30%. Unfortunately we were unable to let the grass wilt for 24 hours after cutting as heavy rain was forecast for the following day. Ideally we would have cut the grass in late afternnon to ensure high sugar content and wilt. We did shake the field once before baling to remove as much water as possible.
Tuesday, March 13, 2018
