Growing and feeding components of dairy rations is a balancing act that must factor affordability, availability, agronomic conditions and nutrient content.
Increasingly, sorghum is an alternative to corn being embraced by nutritionists and dairy producers. In the “Sorghum in Dairy Cattle Production Feeding Guide,” Kansas State University researcher Michael Brouk and Texas A&M researcher Brent Bean point out the advantages that sorghum possesses as a dairy feedstuff. They examined the feeding of sorghum grain, sorghum forage and sorghum distillers grain. The benefits of utilizing sorghum include:
- Sorghum can be raised in areas of low rainfall, requiring about half of the precipitation of corn for comparable yield.
- Regrowth potential allows sorghum to be harvested multiple times.
- Grain sorghum contains more crude protein than corn.
- Fiber, as measured by acid detergent fiber (ADF), is higher for sorghum grain compared to corn.
- Sorghum forage is highly flexible, and can be utilized for grazing pasture, hay production, silage and green-chop.
In dairy heifer rations, sorghum silage is an attractive option because its lower energy and high fiber content promote rumen development without excessive weight gain. In areas of limited moisture, sorghum forage also is highly cost-effective, because more tonnage can be grown locally without the cost of shipping forages from other areas.
The researchers noted that processing is an important factor in releasing sorghum’s greatest nutritional potential. They identified steam flaking as the most effective method of disrupting the protein matrix surrounding the starch granules in sorghum grain, which is important for utilizing sorghum starch in the rumen.
Sorghum is used as a distiller’s grain in some parts of the Midwest and Southwest. The resulting feed product is very similar to corn-based distillers, except that it may be as much as 3 percent higher in crude protein. Sorghum-based distillers is also likely to have a darker color, because of the difference in seed-coat color of sorghum grain. Brouk and Bean emphasize that this color difference has no bearing on quality of the feedstuff.
Finally, they emphasize the importance of nutritional analysis and good ration-balancing practices when utilizing sorghum products in dairy rations, to both determine their value and reap desirable results.