Why maize silage?
Date: 17 August 2017
While ryegrass-clover pasture continues to be the backbone of New Zealand livestock systems, variable and more severe weather patterns have created challenges for farmers seeking to build systems which are both profitable and environmentally sustainable.
Therefore, a growing number of farmers have recognised the importance of high quality supplementary feeds such as maize silage to ensure their business is profitable, regardless of the season they are faced with.
Among the most significant reasons to grow maize is its efficacy in reducing nitrogen leaching. Growing a high-yielding maize crop removes excessive soil nutrients which have dropped out of the root zone of shallow-rooted pasture species.
Feeding maize silage in conjunction with pasture dilutes dietary protein levels, in turn reducing the amount of both nitrogen leaching risk and urinary nitrogen.
Growing maize on effluent paddocks also reduces feed cost by delivering high maize silage yields with reduced crop input costs. A two year on-farm study funded by the Foundation of Arable Research (FAR), DairyNZ, Environment Waikato and Genetic Technologies Limited showed that maize silage crops grown on effluent paddocks with no additional fertiliser (no base, starter or sidedress) yeilded an average of 26.1 tDM/ha.
But the benefits of growing and feeding maize to your livestock doesn’t end there.
Maize is an ideal break crop in a pasture renewal process. The cultivation process allows farmers to apply fertiliser, incorporate lime and address drainage issues that may have been negatively impacting pasture persistence. Cropping removes the normal feed source for pasture pests such as Black Beetle, Argentine Stem Weevil and pasture nematodes.
A key benefit of maize silage is that, providing it is well compacted and sealed, it can be stored on-farm and used to fill genuine feed deficits. Feeding supplements results in pasture substitution reducing grazing pressure. Forages such as maize silage have higher substitution rates than concentrates and can be used to manipulate farm pasture cover levels reducing overgrazing and improving pasture persistence.
Maize silage is also a top cow conditioner, due to its high level of carbohydrate.
Many New Zealand cows are dried off early because their body condition is too low, which affects milk production as well as reproduction and animal health.
DairyNZ information shows a cow calving at CS 4.0 will take 8-10 days longer to start cycling than if she calved at BCS 5.0, resulting in a later calving date and up to 15-20 kg/MS less in the following lactation.
Feeding maize silage as alongside pasture throughout the year also helps support high heifer liveweight gains, which is fundamental to achieving high production and meeting reproductive targets in the future.