23 Jan What can you tell me about alternative cattle feeds (concentrates) as supplements for pasture-based cattle production?
Answer: Corn is grown as animal feed on many small diversified farms in rotation with pasture, legumes, or vegetables and is an excellent source of low-fiber energy for grazing ruminants. However, if corn is fed in high quantities, forage intake will decline. Five or six pounds per day for cattle will generally provide enough supplemental energy without decreasing forage intake. Limiting corn supplementation to no more than 0.5 to 1.0% of body weight per day is recommended for cattle on pasture (Sewell, 1993). On high-quality pastures, energy is often the limiting nutrient. Digestible fiber feeds are good for ruminants on high-quality forage because they do not reduce intake and provide energy for protein metabolism. Examples are corn gluten feed (corn gluten meal plus the bran), wheat midds (screenings from wheat flour processing), and whole cottonseed. Others include beet pulp, citrus pulp, dried brewers grain, and soybean hulls. Supplementation with digestible fiber feedstuffs at rates of 0.2 to 0.8% of body weight has yielded favorable results (Bohnert, et al., 2004). Milling Feed manufacturers use mills to reduce the particle size of feedstuffs. The two most commonly used mills are hammer mills and roller mills. Hammer mills produce feeds with a wide range of particle sizes and are useful for both fiber feedstuffs as well as grains. They are generally more efficient than roller mills but have the propensity to develop more heat, noise, and dust than roller mills. Roller mills are generally more complicated than hammer mills and produce a less uniform feedstuff, but they are energy-efficient and produce much less dust and heat than hammer mills. Roller mills also are not good at processing fiber feeds as are hammer mills (Koch, 2002). When feeds are milled, the particle size reduction tends to increase the surface area of the endosperm in the grain, allowing for better contact of the grain carbohydrates with the animal’s digestive enzymes. Milling also allows for easier mixing of feedstuffs for mixed feeds and total mixed rations (TMR) (Goodband, et al., 2002). But when grains are milled too much, and the particle size is too small, the feed process becomes much less energy-efficient and can create dust problems, thus resulting in feed losses. Milling is warranted when feeding whole grains especially for finishing diets for beef cattle and rations for lactating dairy cattle. Wheat, barley, and corn can be rolled or hammer-milled to increase the surface area of the endosperm for aiding digestion. The primary factor to determine particle size is the kind of mill that is used and the size of the screen used. A hammer mill will produce spherical particles with a higher bulk density or weight per unit volume than a roller mill will, whereas a roller mill will produce more irregular shaped particles of a more uniform size (Koch, 2002). The shape of the ridges on the rollers of a roller mill will also impact the particle size of the feed that is milled. Roller mills generally yield feedstuffs that are smaller, more uniform in size, and with a higher calculated surface area (in cm? per gram) than do hammer mills, and are much easier to use than hammer mills. The following is a rough breakdown of the applicability of the two types of mills (Heimann, 2008): Roller Mill Cracking, crimping, minimum fines Coarse grinding, textured feeds Grinding for pelleted feeds: corn, wheat, milo Hammer Mill Grinding for pelleted feeds: corn, wheat, milo Grinding for pelleting feeds: oats, barley, fiber Rendering applications: wood, hulls, etc. Alternative Feedstuffs Rebecca Schafer, Extension educator with South Dakota State University, lists the following factors when looking for alternative feeds: 1. Accurate identification of the alternative feed 2. Availability and consistency of availability 3. Nutrient composition and nutrient availability 4. Consistency of composition 5. Suitability 6. Perishability 7. Freedom from health hazards 8. Special handling, processing, and storage requirements 9. Effect on end product 10. Storage space 11. Legality 12. Cost Wheat Midds Wheat midds are a co-product of the wheat milling industry and include screenings, bran, and germ. Protein concentration is often higher than 14% and, depending on the environment in which it was grown, can have an energy content comparable to corn (Dhuyvetter, et al., 1999), although these figures can be highly variable. Wheat midds are a high digestible fiber feed, but since the fiber particle size is small, it is not a good source of roughage and should not be a substitution for forage or other forages in the diet, as the fiber in wheat midds is highly fermentable. Roughage forages are needed to maintain rumen function and health. Introduce wheat midds to cattle slowly to avoid digestive disturbances, up to about 1% of body weight per day (10 to 15 pounds per head per day) to provide protein and energy supplementation on low-quality and winter forages and energy supplementatio0n on high-quality pastures. Field Peas Field peas are a nutrient dense feedstuff that can be used as a protein or energy supplement for cow-calf herds. Protein ranges around 23% and energy (TDN) is comparable to corn at 87% (versus 90% for corn). Studies have shown that field peas can be fed either ground, rolled, or whole with no difference on animal performance (Anderson, et. al, 2007). Field peas are particularly suited as a protein supplement for beef cattle on low quality forages. Four pounds of 23% CP field peas per day per head will provide about one pound of protein per day which would be adequate for beef cattle supplementation on low-quality forages. References Anderson, Vern, Greg Lardy, and Breanne Ilse. 2007. Field Pea Grain for Beef Cattle. North Dakota State University. www.ag.ndsu.edu/pubs/ansci/beef/as1301.pdf Bohnert, D, D. Chamberlain, S. Filley, R. Hathaway, J. Males, B. Nisley, J. Oldfield, C. Parsons, R. Pawelek, G. Pirelli, M. Porath, and P. Schreder. 2004. Beef Cattle Nutrition Workbook. Oregon State University Extension Service. www.oregonstate.edu/dept/eoarc/sites/default/files/abouthome/scientists/documents/DWB26.pdf Dhuyvetter, John, Karl Hoppe, and Vern Anderson. 1999. Wheat Middlings: A Useful Feed for Cattle. North Dakota State University. www.ag.ndsu.edu/pubs/ansci/livestoc/as1175w.htm Goodband, Robert D., Mike D. Tokach, and Jim L. Nelssen. 2002. The Effects of Diet Particle Size on Animal Performance. Kansas State University Agricultural Experiment Station and Cooperative Extension Service. www.ksre.ksu.edu/library/grsci2/mf2050.pdf Heimann, Mark. 2008. Advantages and Disadvantages in Particle Size Reduction Techniques. Waterloo, IA: Roskamp Champion. Koch, Kim. 2002. Hammermills and Roller Mills. Kansas State University Agricultural Experiment Station and Cooperative Extension Service. www.ksre.ksu.edu/library/grsci2/mf2048.pdf Schafer, Rebecca. 2007. Cattle, Corn, and Alternative Feeds. South Dakota State University. www.thecattlesite.com/articles/840/cattle-corn-and-alternative-feeds Sewell, Homer. 1993. Grain and Protein Supplements for Beef Cattle on Pasture. University of Missouri Extension. www.extension.missouri.edu/publications/DisplayPub.aspx?P=G2072