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MSU Fergus County Extension
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Fall
is the Time to Test Your Hay Given the wide variety and condition of hays that will be fed in Montana this winter, not to mention variable livestock and environmental conditions, we strongly recommend testing your hay this fall. Why test hay and forages? Hay and other stored forages are our major winter feeds. Hay analysis lets you develop a good winter feed program. Producers should routinely get a representative analysis of all hay. In the past two years, ranchers have purchased hay from distant locations at fairly high prices. Hay inspection and forage analyses have helped assure buyers of decent hay quality. Hay is fed in large quantities, and thorough forage testing is the first step to design a winter-feeding strategy. Hay delivers energy, protein, vitamins and minerals to cattle, sheep and horses, and these measures of hay can be tested accurately and inexpensively. In dairy states, hay prices are directly related to forage quality, primarily fiber and protein levels. During 2001, most ranchers made significant changes in their operations to adjust for forage losses in drought-stricken rangeland and pastures. The drought necessitated such costs as shipping herds to pasture, purchase of high value hay and hauling stock water. Many ranches culled or weaned early to reduce feed costs in the upcoming winter. Hay prices throughout the state remain at fairly high levels. How much hay do you need? Depending on your location in Montana and winter conditions, you will need a one- to four-month supply. Montana ranchers historically have stored about one ton of hay per cow (a guideline based on roughly 30 pounds of hay per cow for 60 to 70 days). This guideline is useful, though it does not allow for larger cows, poor-quality roughages, extremely cold weather, or the possibility of feeding hay into May. Regardless of winter precipitation, pasture conditions next spring could still be limiting, so consider laying in 20 to 25 percent more hay than in typical years. Every hay lot should be sampled separately. A hay lot is defined as hay taken from the same field and cut, harvested within 48 hours, and stored under the same conditions. It may range from a pickup load to 200 tons. Samples are best obtained using a hay probe to randomly sample bales within a stack. The probe tip, which should be sharp, is inserted 12 to 18 inches into bales. Square bales should be sampled near the center of their ends, and round bales should be sampled on round edges. A minimum of 20 random cores should be collected at different heights in a haystack and combined. Every effort should be made to obtain a random and representative sample, otherwise the forage quality analysis may not be representative of what is actually fed. The composite sample from each hay lot, which will be 1/2 to 3/4 pound, should be mixed, sealed in plastic bags, labeled and submitted to a forage-testing laboratory. Many labs are available for forage quality analyses. Most commercial hay producers use laboratories certified for proficiency through the National Forage Testing Association. And hay sampling and forage analyses are now offered as a service by many feed companies for ranchers who routinely purchase supplements and feed additives. While certified labs are useful in hay marketing, there are several other good labs for ranchers wanting routine analyses of their own hay. A complete directory of NFTA laboratories is available on the Web at http://www.foragetesting.org/labs.php or at your local Montana State University Extension Service office. What tests should be run on hay? The definition of hay quality is the potential of a forage to produce a desired animal response. Hay quality includes palatability, digestibility, intake, nutrient content and anti-quality factors. For a winter-feeding program in Montana, the primary forage quality tests to request are crude protein (CP), acid detergent fiber (ADF) and neutral detergent fiber (NDF). Crude protein levels of alfalfa and grass/alfalfa hays in Montana typically range from about 9 to over 20 percent, in some cases protein supplements will be required. The ADF component is cellulose, lignin and ash. Low ADF values are correlated to increased digestibility. The ADF value can be used to estimate total digestible nutrients (TDN), and net energy predictions for maintenance, growth or lactation. The NDF consists of cell wall components; a low NDF value is correlated with potential high intake levels. Daily dry matter intake (DMI) as a percent of an animal's body-weight can be estimated directly from the NDF values. Labs use a variety of accepted testing procedures. The cost for analysis of CP, ADF and NDF ranges from about $15 to $40, with a turnaround time of 2 to 14 days, depending on the laboratory. Other useful analyses for Montana forages include calcium, phosphorus, potassium and magnesium, and sometimes the trace minerals copper and zinc. Nitrate concentration is an example of an anti-quality forage factor. Many of our small grain hays (barley, hay barley, oat and wheat) can accumulate toxic levels of nitrate, particularly when grown under stress conditions. We strongly recommend that all small grain hays grown in Montana since 1999 be tested for nitrate concentration prior to feeding. When the forage analyses come back from the laboratory, it is time to use the information to balance rations to provide desired levels of productivity (late gestation, early lactation, replacement heifers, etc.). Dave Phillips, MSU Fergus County Extension agents has computer software in the office that can be used to suggest balanced rations for cows and replacement heifers. These programs called Balancer and Grower are useful in helping ranchers determine their options in designing winter-feeding programs.
CD-ROM version of the Cow-Calf Management Guide and The CD-ROM version of the Cow-Calf Management Guide and Cattle Producers Library is now available as a stand alone cd. Production and Associated Costs of Heifer Development (The Benchmark Values) Producers consigned a combined total of 549 heifers from 1993, 1994, 1995 and 1996 to be developed from a weaned heifer calf to a bred replacement heifer. The heifers were spring born, with a typical birth date of mid March, represented a variety of breeds and crosses and were managed to reach 70% of their projected mature weight at breeding. Heifers were synchronized to facilitate AI during May. Following AI, heifers were exposed to cleanup bulls for a minimum of 45 days. The heifers averaged 84.4 lbs at birth, 567 lbs at 205 days of age, 5.6 frame score with an estimated mature weight of 1220 lbs. Respiratory distress was the primary health problem requiring treatment, with foot rot the second most common health-related problem. Mortality was .73% with morbidity at 6.2% across all four years. The genetics and management of these heifers resulted in 92.6% of the heifers returning home pregnant. Overall, 42.9% were bred to AI service, 49.7% to natural service and 7.4% were open. Heifer Development Costs (1995-96 not
included)
return to index Making
Sense of Ultrasound and Carcass Measurements U.S. beef production and marketing systems are changing. Production segments are becoming more coordinated; sometimes by formal business alliances, sometimes by improved information transfer and measurement of value. Systems are becoming more product-oriented than commodity-oriented. As a consequence, cattle producers have incentives to make genetic changes in carcass traits. A variety of genetic tools are available to help beef producers tailor cattle to specific markets and environments. EPDs are the most effective for making directed genetic improvement within breeds. Compared to most growth traits, traditional performance and progeny testing for carcass merit is more difficult to complete. Carcass traits cannot be measured directly on potential parents, i.e., the measurements made on a chilled carcass cannot be duplicated on live animals. Carcass measurements on progeny or other relatives of potential parents are expensive to collect. Ownership of calves can change several times prior to slaughter, and cattle are typically moved to different locations during their lifetime; hence, maintaining animal identification and information feedback to cow-calf breeders are difficult tasks. Nevertheless, carcass traits are moderate to highly heritable. Problems associated with direct measures of carcass quality have motivated searches for measurable traits on potential parents that could provide carcass quality information. Real-time ultrasound has proved to be an effective technology to meet this goal. Currently, many breeders use ultrasound to identify differences in carcass merit among young cattle. Yet, I sense that confusion exists over how this information relates to the actual carcass measurements made on cattle after slaughter. Though difficult, such information is desirable because an ultrasound measurement made on potential breeding stock raised under ranch conditions (e.g., yearling bulls or heifers) is not exactly the same as the direct measurement made on carcasses from animals grown in a feedlot, but a genetically correlated trait (see sidebar). Due to this genetic correlation, the ultrasound measurement explains (or accounts for) some but not all of the variation in the carcass trait (see Figure 1). For example, an ultrasound ribeye area measured on a yearling bull is useful in predicting the ribeye area EPD for that bull, but not as useful as a direct measurement would be. Estimates of genetic correlations between carcass measures and ultrasound measures are needed before EPD for carcass traits can be computed from ultrasound data. Accurate estimates of these statistics are not easy to obtain. Therefore, breed associations have taken one of four approaches to computing EPD for carcass traits: 1) using carcass data to compute
carcass EPD, Confusion may arise when bulls have both ultrasound EPD and carcass EPD. It's possible that these EPD may rank bulls differently. First, we must remember that these are different, although genetically correlated traits. Another likely contributor to this problem may be different amounts of progeny data for ultrasound measurements versus direct carcass measurements--both among the bulls evaluated and among the bulls' ancestors. Because ultrasound measurements are made on potential parents, one might predict that future carcass trait EPD will be essentially based on ultrasound measurements. However, electronic animal identification, animal tracking networks, and web-based data transfer might facilitate a different course. If this electronic technology is widely adopted, and if the expense is low, direct carcass measures might eventually be the dominant source of genetic information on carcass traits. This article was originally printed in the "Beef: Questions & Answers newsletter," produced by the MSU Extension Service and Montana Beef Council.
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