Feeding grasses to dairy cows
Harvest Best Practices
In our last article, we explored some of the aspects related to the nutritional value of grasses for dairy diets. In this last article about feeding grasses we will discuss a bit more about the nutritional value of grasses based on stage of development.
One key point to pay attention to with grasses is harvest timing, to preserve a good balance between quality and quantity. Ideally, grasses should be harvested at the boot stage or very early heading. Dr. Larry Chase’s goal for the value of NDF in grass silage for early lactation cow rations is 50-55% NDF. The below table shows data from work done by researchers from the University of Wisconsin, with the chemical composition of different perennial forages at different maturity stages, where we can compare legumes with grasses and have an idea of the levels of protein and fibre that grasses can have according to their stage of maturity.
Grasses ensile very well because of their relatively high sugar content. Geoff Brinks, from the USDA, says that, like alfalfa haylage, grasses should be ensiled at 60-65% moisture, although they can be made a little wetter. As usual with silages, proper compaction is essential maybe even more with grass silages, because at the same moisture, and with the same amount of packing, the density of grass silage is lower than that of alfalfa. He also recommends that if making grass baleage, producers should wrap it as soon as possible and to use a minimum of 6 mm of plastic.
Deciding what forages should be produced on the farm is largely a decision based on types of soil and climate. In many areas, there are crop acres that are not suited to alfalfa production but can be used very effectively for growing grasses. Research as been showing that grasses can be a good alternative to dairy diets in terms of milk production.