Introduction
Optimizing a ranch’s feed resources often requires strategic supplementation of standing forage with a processed protein, energy or mineral product. However, protein and energy supplements do not necessarily have to come out of a sack. Often, a more economical supplement is wrapped in twine or wire and is known as the number one agricultural crop of Nevada - alfalfa hay.
Hay which does not meet the dairy industry specifications can often be purchased cheaper than processed supplements when comparing price on a “per pound” of actual nutrient basis (Table 1). A combination of home-grown hay, purchased alfalfa hay and a mineral supplement can be used to balance the nutritional needs of the cow herd during critical periods of the year. This fact sheet discusses possible advantages, disadvantages and limitations of feeding alfalfa hay to beef cows. Prices for various sources of protein are somewhat volatile and may change significantly from year to year. The information shown in Table 1 and Table 5 are developed as interactive Excel spreadsheets. The spreadsheets can be found on the University of Nevada Cooperative Extension Web site under agricultural publications (2009 Restaurant Industry Forecast). By using the interactive spreadsheets, you can compare feeds on a current price basis. The spreadsheet reflected inTable 1 allows you to enter the feed analysis data and current price of up to two chosen feeds to determine the “per pound” cost of protein. The spreadsheet reflected inTable 5 allows you to enter the nutrient data to determine if the quality of forage will meet or exceed the nutrient requirements for either a 1,000 pound or 1,200 pound mature cow over an annual production cycle.
What Is Alfalfa?
Alfalfa is a legume, a nitrogen fixing plant that can extract nitrogen from the atmosphere and incorporate it into plant proteins. Other legumes include clovers, vetches, peas, beans, sainfoin and birdsfoot trefoil. Alfalfa is grown throughout the United States and is capable of producing more than 1,800 pounds of protein per acre per year. Alfalfa is the No. 1 cash crop grown in Nevada and is a major feed ingredient for the beef industry throughout the country.
Alfalfa as a Protein Source
Beef producers often use the term "high quality forage" to describe a high protein, low fiber feed. Table 1 shows the typical protein, energy, fiber and mineral content of various feeds commonly available to beef producers. Early cut alfalfa (late bud, early bloom stage) may vary from 16 to 20 percent crude protein on an “as fed” basis. Even late cut alfalfa typically contains 12 to 15 percent crude protein. Fiber content of alfalfa hays range from 20 to 28 percent. In contrast, grass hay averages 8.4 percent crude protein and 31.4 percent fiber. Ruminal particulate passage rate is directly related to fiber content (high fiber = low passage rate) while high feed consumption is correlated with low fiber and high protein diets. Passage rate of alfalfa is approximately 36 hours versus up to 70 hours for lower quality forages. The quality of alfalfa protein is excellent with more than 70 percent of its total protein being digestible.
Table 1. Average Quality and Price of Feeds Commonly Available to Northern Nevada
*table here
The price per pound of actual protein based upon the given price per ton for each feed is also shown in Table 1. The $90 per ton mid-bloom alfalfa (beef quality alfalfa hay) is the most economical feed available to beef producers when considering protein alone. The $0.24/pound of actual protein is cheaper than the average grass hay listed and significantly cheaper than many of the packaged supplements listed.
Alfalfa as an Energy Source
Alfalfa has one of the highest feeding values of forages. It has always been perceived as an excellent source of protein, but is sometimes underestimated as an energy source. A ton of alfalfa hay contains as much total digestible nutrient (TDN) as 25 bushels of corn (and as much protein as two-thirds ton of soybean meal). Beef cows are more likely to be fed rations more deficient in energy than in protein, particularly during the last trimester of pregnancy and postpartum (after calving). A beef cow needs high energy hay to regain body weight after calving, produce milk for her calf, and rebreed in 40 to 90 days after calving.
Some grass hays may be as high in digestible dry matter as alfalfa; however, those hays will be digested slower than alfalfa. As mentioned earlier, some alfalfa hay will pass through the rumen of a beef cow in about one-half the time required by grass hay (36 versus 70 hours). Therefore, animals fed alfalfa hay tend to gain faster, produce more milk, and maintain themselves in better condition than those fed other forages. This increased gain is primarily associated with an increase in intake, and the benefits would be negligible if the alfalfa was limit-fed (controlled intake).
Alfalfa as a Source of Minerals and Vitamins
Alfalfa can provide most minerals and vitamins at less cost than if they were supplied from other processed sources.
Minerals
If one pound of alfalfa hay is fed per 100 pounds of “bodyweight”, the beef animal will normally meet its daily requirements for calcium, magnesium, potassium, sulfur, iron, cobalt manganese and zinc. Phosphorus levels of alfalfa are more moderate, but are still high enough that, if fed at the above rates, will supply about two-thirds of the daily requirements needed. The high level of calcium in alfalfa is especially important for lactating cows, young developing replacement heifers and bulls. However, the mineral content of alfalfa is related to fertilization and local soils. Hay quality tests are required to determine the actual amount of minerals in a given lot of hay. Beef cattle, fed alfalfa hay during the winter, are less likely than those fed grass hay to get grass tetany or hypomagnesemia tetany at turn out time. The elevated magnesium levels of alfalfa seem to curb the problem.
Vitamins
Leafy, green alfalfa hay is unusually high in carotene, the precursor of vitamin A. Vitamin A is the most common beef cow vitamin deficiency. Good quality alfalfa hay can usually furnish all the vitamin A needs of beef animals. In addition to the many dietary functions of vitamin A, this vitamin may also have some therapeutic value, and it may be a contributing factor in preventing "shipping fever complex" and other disorders associated with animal stress. Because vitamin A will leach out of hays stored over extended periods of time, freshly harvested alfalfa is usually the best source of vitamin A.
Vitamin/Mineral interactions
Alfalfa is usually a good source of vitamin E and selenium, depending on the nutrient status of the soil on which the hay was grown. Selenium is often deficient in soils across Nevada. "White muscle disease," which sometimes causes serious losses of calves, is caused by a deficiency of vitamin E and selenium. Sun-cured alfalfa hay is also a source of vitamins D and K as well as riboflavin and niacin.
Alfalfa as a Fall Supplement
Alfalfa may be used economically as a protein source for cattle in their midtrimester of pregnancy grazing low quality forages (such as fall grazing of crested wheat). Table 2 shows the nutrient content of dormant crested wheatgrass and nutrient requirements of the beef cow in her mid and last trimesters of pregnancy. Protein supplementation is essential to maintain the body condition of the cow prior to entering the winter months and her last trimester of pregnancy. Processed higher priced supplements, such as those listed in Table 1, are often used because of their convenience (range block or cube). By feeding 5 pounds of alfalfa every day or 10 pounds every other day, producers can meet the nutrient requirements of the beef animal for less cost. Not only does alfalfa furnish the needed protein, it also stimulates the rumen which causes the animal to increase the consumption and digestibility of lower-quality forages.
Table 2. Nutrient requirements of a 1000 pound mature non-lactating cow and nutrient value of dormant crested wheat.
aCombined nutrient value of dormant crested wheatgrass and 5 pounds of alfalfa hay
* Figures in parenthesis do not meet the nutrient requirements of a 1000-pound non-lactating pregnant cow in the last trimester.
*table here
Winter Feeding Cows Alfalfa and Grass Hays
Many ranches produce a significant quantity of low-quality grass hay. Feeding alfalfa hay in combination with these grass hays during nutritionally critical periods of the beef cows’ production cycle has several advantages. Table 3 shows that the average Nevada grass hay falls short of fulfilling the protein and energy needs of a 1000 pound. cow postpartum (right after calving). By feeding a 50 grass hay, 50 percent alfalfa ration, the protein requirements are met. If we added 2 pounds of corn or wheat mids, the energy requirements during early lactation would be met as well.
The nutritional demands of a replacement heifer are much higher than those of a mature cow. Not meeting those nutritional demands results in delayed conception for that heifer's second calf, a weaker fetus, lower colostrum quality and a lower weaning percent. Table 4 shows that a 50 percent grass, 50 percent alfalfa hay diet along with 3 pounds of an energy concentrate is required to meet the nutritional demands of a heifer in her last trimester of pregnancy and postpartum.
Bloat Problems Associated With Feeding Alfalfa
The danger of bloat can be lessened by following several management practices.
- Do not feed dairy-quality alfalfa hays to beef cattle.
- Do not allow leaves to build up in the feed bunk.
- Allow plenty of feed space for all animals to have access at once.
- Feed alfalfa in conjunction with a higher fiber feed such as grass hay.
- Never introduce hungry animals to leafy alfalfa.
- Remove and sell animals that are chronic bloaters.
- During wet weather, take extra precautions on the aforementioned points.
- Bloat control may also be aided by feeding an antifoaming agent (i.e. polaxalene). Bloat Guard© is such a product and is available in medicated blocks, in commercial pelleted feeds (used as a top dress), or a liquid that can be added to the water (Fact Sheet 89-22).
Table 3. Nutrient requirements of a 1,000-pound pregnant cow postpartum and nutrient value of common feeds
* Figures in parenthesis do not meet the nutrient requirements of a 1000-pound pregnant cow postpartum.
*table here
Table 4. Nutrient requirements of an 850-pound pregnant two-year-old heifer in last trimesterof pregnancy and postpartum and nutrient value of common feeds
* Figures in parenthesis do not meet nutrient requirements of an 850-pound first calf heifer at any stage of pregnancy or postpartum.
*table here
Feedability of Alfalfa
The largest percentage of nutrients (protein and energy) is contained in the leaves of alfalfa. The stems are similar in nutrient content of grass hay. Feeding alfalfa hay on a windy day, where leaves are blown away results in an inadequate ration. The passage rate of alfalfa hay is approximately 36 hours vs. 70 hours for grass hay. By feeding the 50 percent grass – 50 percent alfalfa ration in a windbreak area, the leaves are consumed thus balancing the ration.
Table 5. Basic Nutrient Requirements For Beef Cows
*table here
Summary
Strategically, winter feeding alfalfa hay in conjunction with grass hays and energy supplements is often an economically sound practice for beef producers. Alfalfa is typically the cheapest feed supplement in late summer and early fall when grazing cows in their mid-trimester of pregnancy on low quality forages. During most years, excellent quality alfalfa hay is locally abundant and is often underutilized as a supplement in the beef cow industry.
Literature Cited
- Banta, J. 2008. Adjusting to High Fuel and Fertilizer Prices. Proc. Agrilife Research Center Technical Report No. 2008-0. Texas A&M University.
- Brandyberry, S.D., T. DelCurto, and R.F. Angel. 1992. Physical form and frequency of alfalfa supplementation for beef cattle winter grazing Northern Great Basin rangeland. Proc. West. Sec. Amer. Soc. Anim. Sci. 43:47.
- DelCurto, T., R.C. Cochran, T.G. Nagaraja, L.R. Corah, A.A.Beharka, and E.S. Vanzant. 1990. Comparison of soybean meal/sorghum grain, alfalfa hay and dehydrated alfalfa pellets as supplemental protein sources for beef cattle consuming dormant tallgrass-prairie forage. J. Anim. Sci. 68:2901.
- Hess, B., L.J. Krysl, M.B. Judkins, K.K. Park, B.A. McCracken, and D.R. Hanks. 1992. Supplementation of cattle grazing dormant intermediate wheatgrass pasture. Proc. West. Sec. Amer. Soc. Anim. Sci. 43:70.
- Momont, P.A. 1992. Ration balancing. Cow-Calf Management Guide. CL-300. NRC. 1984.
- Nutrient requirements of beef cattle: Seventh revised edition, update 2000. Board on Agriculture
- Rossi, J. and Silcox, R., 2007. Protein Supplements for Cattle. Bulletin 1322 University of Georgia, Cooperative Extension
- Ruminant Nitrogen Usage. National Academy Press, Washington, DC.
- The spreadsheets for Tables 1 and 5 can be obtain by contact the authors below.
