Corn silage feeding strategies vary depending on animal age, level of production, and physiological status as well as the other forages being fed, if any. Because of its high grain content, feeding strategy for corn silage fed to high producing cows differs from most other forages. Corn silage quality factors that are important to consider when balancing rations are energy content, NDF content, NDF digestibility, length of cut, starch content, and starch digestibillity.
Corn silage is a high energy feed source for ruminants. Being part forage and part grain, it has characteristics of both feed types and is a valuable component of dairy rations in regions where corn can be grown. Nutritionally, corn silage is lower in crude protein (CP) and higher in digestible energy (DE) than other forages.
One of the most critical factors affecting the process of fermentation is the amount of water present in the crop at ensiling. Silage microbes need water in order to thrive and multiply. That is why drying hay, for example, is effective at preventing most microbial growth. However, the amount of water is important in determining which microbes grow best. In silage, we normally quantify water in terms of dry matter (DM) content of the crop. Thus a low DM silage contains more water than a high DM silage.
Quality of corn silage is determined by energy content and intake potential as well as content of protein and minerals. Methods used to evaluate corn silage quality include chemical methods such as fiber analysis, biological methods such as fermentation with ruminal microbes, and instrumental methods such as near-infrared reflectance spectroscopy (NIRS) which predicts nutrients rather than measuring them directly.
Feeding silage to dairy cattle.
Corn silage is used for feeding all dairy cattle on the farm: growing animals, dry cows, and lactating cows. It must be supplemented with protein, minerals, and sometimes energy to meet the animal's nutrient requirements. Although corn silage is occasionally used as the only forage for dairy cattle, it is usually fed with a complimentary forage such as alfalfa which is higher in crude protein but lower in energy.