Maize silage has always been popular as the foundation of mixed forage systems but new research has now helped identify why it is such a valuable feed.
Adam Clay, ruminant manager at Trouw Nutrition GB, says: “Modern maize varieties have the potential to deliver high energy yields.
“Most farmers are keen to get maize into the diet as soon as possible, commenting they see a response both in terms of feed intakes but also in how cows perform. This is largely a consequence of how it is fermented in the rumen.”
To optimise milk production, the rumen has to work efficiently. Mr Clay explains the key to this is to have a sufficient mass of microbes in the rumen which need to be active, producing the volatile fatty acids required by the cow. To do this they need energy. He stresses the type and quantity of energy are both important.
“This energy needs to be provided in a ‘rumen healthy’ form which means paying close attention to fast energy sources which are fermented in the rumen. If too much rapidly utilised energy is supplied you can tip the cow over into acidosis which has to be avoided.
Mr Clay says new research shows maize has the ability to supply energy as both rapidly and slowly fermentable carbohydrates while maintaining a healthy rumen.
According to research into how feeds are utilised in the rumen by Nutreco, Trouw Nutrition GB’s parent company, maize silage provides a good balance of rapidly fermented energy combined with good proportions of by-pass starch. This means it is supplying the energy in the form the rumen requires, fermented at a rate which means it is effectively utilised by the microflora, resulting in a healthy and efficient rumen.
“The extent and rate at which maize starch is fermented means it is an excellent feed in terms of its impact on rumen health and efficiency which can explain why it is such an effective feed. However, it also has a direct impact on the cows’ ability to produce higher yields.”
Mr Clay explains milk production is determined by the end products of digestion and these are directly linked to the ingredients in the diet. The key end products of digestion for milk yield are termed glucogenic nutrients which are primarily produced in the rumen from propionate fermentation of starch.