Corn silage

Corn is actually a kind of grass, but we don't think so, because corn has a high grain yield. When nutritionists or farmers discuss grasses, the focus is usually on cold or warm season pastures such as Italian ryegrass, triticale or sorghum. Although corn is not recognized as a kind of grass, we do think corn is feed. There is a certain conflict here. If silage corn is a kind of feed, we don't think it is grass due to the grain, then how do we define this kind of feed in the diet? Many nutritionists and farmers allocate 100% of the feed value to corn silage, and then monitor the ratio of grains or roughage content in the diet. The awareness of the impact of silage corn on the diet needs to be improved.

In terms of classification, corn silage is a mixture of stems, leaves and grains of approximately 50:50. The extraordinary yield and efficiency per acre of corn silage are closely related to the grain. Therefore, corn silage yield is usually about 50% or more driven by grain yield. The yield gains for plant breeders also mainly come from the grains. In addition, many corn silage prices are determined based on grain yield. The stems and leaves of a corn plant are collectively referred to as stalks. Straw brings fiber and energy to the diet. In order to better evaluate the nutritional properties of corn silage, some breeders have tried to separate the stalks from the kernels. However, it takes considerable effort to separate the stalks and grains for the silage test during the semi-milk ripening period, and we do not recommend this. Returning to the genetic blueprint of maize, about 100 years of seed genetic progress has emphasized plant health, cold tolerance, grain yield, and other important characteristics. Corn breeders evaluate grain quality in their projects, but it should be noted that the desire of grain farmers for grain quality is equivalent to increasing bushel weight, grain density and hardness. This is different from the needs of dairy cows or beef cattle for grain quality. In fact, it is quite the opposite.

When a cow consumes a pound of silage or grain, the first step of digestion is to colonize the feed pellets with free-floating bacteria in the rumen. Many people don’t realize that free-floating rumen bacteria are at work, which is the reason for the initial digestion of the feed. Feed pellets are soaked in rumen juice before digestion, while corn kernels are not soluble in water or rumen juice. In fact, for farmers who grow grain, the hardness factor that improves the quality of the grain makes the grain insoluble in water and the rumen microbes are not easily accessible. The improvement of grain quality associated with high grain yield is actually detrimental to the performance of cattle. A study published by Randy Shaver of the University of Wisconsin and his colleagues showed that large differences in grain hardness or vitrification can be equated to large differences in rumen digestion and energy potential. Kernel processing, fermentation and grinding can partly overcome the grain hardness factor, but cannot completely overcome it. Consult your nutritionist for kernel quality.

Corn silage is a mixture of roughage and grain, so corresponding treatment should be considered. Fiber and starch each contain the same amount of calories, but ruminants can only release 40% to 50% of the calories in corn silage fiber. More importantly, fiber may improve rumen health, while grains cannot. If corn silage is divided into a 50:50 mixture of grain and feed, consult a nutritionist about the level of roughage in your total mixed ration (TMR). In addition to corn silage, other feeds can also be mixed into the diet. Snaplage and earlage are also a mixture of straws and grains. Both of these feeds have much less straw, and may only bring a small portion of forage into the diet. Finally, consult a nutritionist if there is a better way to balance the fiber content in TMR than feed or roughage percentages. Nutritionists may monitor more important diet parameters, including neutral detergent fiber (aNDF), forage aNDF, or indigestible aNDF (uNDF240) levels. Balancing the relationship between these fibers and other energies (such as starch or sugar) will help your herd maintain excellent rumen health and performance.