1998 Cattlemen's Day

Kansas Agricultural Experiment Station Research Reports, Dec 1998

Kansas Agricultural Experiment Station

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1998 Cattlemen's Day

1998 Cattlemen's Day Kansas Agricultural Experiment Station Follow this and additional works at: http://newprairiepress.org/kaesrr Recommended Citation - Thi s report is brought to you for free and open access by New Prairie Press. It has been accepted for inclusion in Kansas Agricultural Experiment Station Research Reports by an authorized administrator of New Prairie Press. Copyright 1998 Kansas State University Agricultural Experiment Station and Cooperative Extension Service. Contents of this publication may be freely reproduced for educational purposes. All other rights reserved. Brand names appearing in this publication are for product identification purposes only. K-State Research and Extension is an equal opportunity provider and employer. Creative Commons License Thi s work is licensed under a Creative Commons Attribution 4.0 License. This publication from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service has been archived. Current information is available from http://www.ksre.ksu.edu. Page RANGE AND GRAZING NUTRITION Effect of Date of Harvest on the Nutritional Quality of Native Grass Hay . . . . . . . . . . . . . . 19 Predicting Voluntary Forage Intake in Cattle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Effects of Processing Whole-Plant Corn Silage on Growth Performance and Nutrient Digestibility in Feedlot Cattle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 HARVESTED FORAGES REPRODUCTION Milking Two or Five Times Daily in the Presence of a Cow’s Own Nonsuckling Calf Fails to Prolong Postpartum Anovulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Increasing Interval to Prostaglandin from 17 to 19 Days in an MGA-Prostaglandin Synchronization System for Heifers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Site of Semen Deposition and Fertility in Lactating Beef Cows Synchronized with GnRH and PGF 2α . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 A Three-Year Economic Evaluation of a Commercial Heifer Development Program . . . . . . . . . . . . . 17 GROWING AND FINISHING NUTRITION Fusobacterium necrophorum Leucotoxoid Vaccine for Prevention of Liver Abscesses . . . . . . . 40 Fusobacterium necrophorum in Ruminal Contents and on the Ruminal Wall of Cattle . . . . . . . 44 Antibiotic Susceptibility of Fusobacterium necrophorum Isolated from Liver Abscesses . . . . . 50 Soybean Hulls in Roughage-Free Diets for Limit-Fed Growing Cattle . . . . . . . . . . . . . . . . . . . . 60 Feeding Systems and Implant Strategies for Calf-Fed Holstein Steers . . . . . . . . . . . . . . . . . . . . . 63 Effects of Added Fat, Degradable Intake Protein and Ruminally Protected Choline in Diets of Finishing Steers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 Betaine as a Dietary Supplement for Finishing Cattle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 Molasses-Fat Blend as an Energy Source and Conditioning Agent in Feedlot Diets . . . . . . . . . . 79 Influence of Melangestrol Acetate (MGA) and Implus-H Implants on Rate of Gain, Feed Efficiency, and Carcass Characteristics of Culled Beef Cows Fed a High Concentrate Ration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83 Development of an In Vitro Procedure to Determine Ruminal Availability of Protein . . . . . . . . 86 MEATS AND BEEF SAFETY Microbial Evaluation of Steam Pasteurization and Comparison of Excision Versus Sponge Sampling Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 Evaluation of Changes in Microbial Populations on Beef Carcasses Resulting from Steam Pasteurization. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 Prevalence of Escherichia coli O157:H7 in Cow-Calf Herds in Kansas . . . . . . . . . . . . . . . . . . . 93 Prevalence, Antibiotic Susceptibility, and Genetic Diversity of Salmonella, Campylobacter, and Escherichia coli O157:H7 Collected at Four Kansas Beef Cattle Feedyards over 13 Months . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 Control of Escherichia coli O157:H7 in Large-Diameter, Lebanon-Style Bologna . . . . . . . . . . . 98 Microbial Shelf Life of Chub-Packaged Ground Beef from Four Large U.S. Processing Plants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 Dry Aging: An Old Process Revisited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 MANAGEMENT Price Discovery Issues for Fed Cattle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106 Grid Pricing of Fed Cattle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109 Projecting Fed Cattle Price Discovery over the Next Decade . . . . . . . . . . . . . . . . . . . . . . . . . . 112 Differences in Efficiency among Kansas Beef Cow Producers . . . . . . . . . . . . . . . . . . . 115 Early Detection of Problem Implants Using Infrared Thermography . . . . . . . . . . . . . . . . . . . . 118 Effects of Feeding Rumensin®in a Mineral Mixture on Steers Grazing Native Grass Pastures 123 Characteristics of Pelleted Wheat Middlings that Affect Sumner Storage . . . . . . . . . . . . . . 129 Beef Cattle Lagoon Seepage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132 ACKNOWLEDGEMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 BIOLOGICAL VARIABILITY AND STATISTICAL EVALUATION OF DATE . . . . . . . . 137 Contribution No. 97-309-S from the Kansas Agricultural Experiment Station. Notice Kansas State University makes no endorsements, expressed or implied, of any commercial product. Trade names are used in this publication only to assure clarity of communication. Some of the research reported here was carried out under special FDS clearances that apply only to investigational uses at approved research institutions. Materials that require FDA clearances may be used in the field only at levels and for the uses specified in that clearance. Contents of this publication may be freely reproduced for educational purposes. All other rights reserved. In each case, give credit to the author(s), name of work, Kansas State University, and the date the work was published. EFFECTS OF SUPPLEMENTAL DEGRADABLE INTAKE PROTEIN ON INTAKE AND DIGESTIBILITY OF LOW-QUALITY BROME HAY Summary The effects of increasing levels of degradable intake protein (DIP) on intake and digestion of low-quality brome hay were evaluated using 16 ruminally fistulated beef steers. Trends were evident for small, positive changes in total intake and digestion with increasing level of DIP supplementation. As a result, total digestible OM intake (TDOMI) increased with DIP supplement-ation but tended to plateau below the highest supplementation level. Introduction Beef cattle in midwestern and plains states are commonly fed brome hay. When harvested at advanced stages of maturity, the quality of brome hay is similar to a number of low quality forages (such as winter range). Previous research with low-quality, tallgrass-prairie forage has demonstrated that supplementation with degradable intake protein (DIP) dramatically improves forage intake and utilization. In addition, the amount of DIP needed to maximize total digestible forage intake has been defined. Because information pertaining to the effects of DIP supplementation on low-quality brome hay is limited, our study was conducted to provide that information. Experimental Procedures Sixteen ruminally fistulated beef steers (average body weight, 675 lb) were blocked by weight and assigned to one of four increasing levels of DIP. Each steer was offered brome hay at 130% of the average voluntary intake for the preceding 5-day period. Supplemental DIP (sodium caseinate; 91.6% CP, 100% DIP) was ruminally infused at 7:00 AM, immediately prior to feeding forage to provide .041, .082, and .124% BW/day; controls received none. The forage contained 65.4% NDF and 5.9% CP, of which 49% was DIP. DIP was estimated using an in situ technique. Following a 10-day adaptation, feed offered, feed refused, and total fecal output were measured for 7 days to calculate digestibility coefficients and determine the intake response. Results and Discussion Total feed intake tended (P#.15) to increase in proportion to increasing level of DIP supplementation (Table 1). Because total diet organic matter digestion also exhibited a weak tendency to increase, when intake and digestion were combined, there was a linear increase (P=.06) in total digestible organic matter intake (TDOMI) as level of DIP supplementation increased. However, the DIP effect on TDOMI tended (P=.17) to diminish at the highest DIP intake. Peak TDOMI was observed at the .082% BW supplementation level, which is likely to be close to the amount of DIP needed to maximize TDOMI. Assuming that 49% of total forage CP was DIP, total DIP consumed by steers on the .082% treatment was approximately 10% of TDOMI. C .081 .128 3.38 5.34 aL = Linear, Q = Quadratic, C = Cubic. bStandard error of the mean (n=4). cDM = dry matter. dOM = organic matter. eDOMI = digestible organic matter intake. fOMD = organic matter digestion. gNDFD = neutral detergent fiber digestion. hDIPI = degradable intake protein intake. EFFECTS OF SUPPLEMENTAL DEGRADABLE INTAKE PROTEIN ON INTAKE AND DIGESTIBILITY OF BERMUDA HAY Summary A study with 16 ruminally fistulated beef steers fed Bermuda hay ad libitum showed that the intake and digestibility of hay was not influenced by increasing levels of supplemental degradable intake protein (DIP). However, the hay used in this study was of medium quality; lower quality Bermuda hay with lower CP may respond to supplemental DIP. Introduction Over the last decade, the approach to protein nutrition in ruminants has shifted from the traditional crude protein (CP) system to a metabolizable protein (MP) system described by the Natural Research Council in the 1996 Nutrient Requirements of Beef Cattle. Metabolizable protein is defined as the true protein absorbed by the small intestine. It is supplied by microorganisms passing out of the rumen and by undegradable intake protein (UIP) that escapes ruminal degradation. The MP system accounts for the degradation of protein in the rumen and separates protein requirements into degradable intake protein (DIP) which is needed by ruminal microorganisms and that needed by the animal (UIP). Crude protein = DIP + UIP. Bermuda hay is a common roughage source for beef cattle in the southern United States, including portions of Oklahoma and Kansas. It typically contains 7 to 12% CP. Previous research on low-quality (CP<7%), tallgrass-prairie forage has demonstrated that DIP is the firstlimiting nutrient for optimal forage utilization, and that DIP supplementation dramatically improves forage intake and digestion. Although the amount of DIP needed to maximize total digestible forage intake has been defined for tallgrass-prairie forage, information on the effects of DIP supplementation on mediumquality hay such as Bermuda is limited. Our study was conducted to determine the impact of DIP supplementation on Bermuda hay intake and digestion. Experimental Procedures Sixteen ruminally fistulated beef steers (average body weight, 653 lb) were blocked by weight and assigned to one of four treatments with increasing levels of DIP. Each steer was offered Bermuda hay at 130% of the average voluntary intake for the preceding 5 days. Supplemental DIP (sodium caseinate; 91.6% CP, 100% DIP) was infused ruminally at 7:00 AM, immediately prior to feeding forage. The forage contained 70.8% NDF and 8.2% CP, of which 60% was DIP. DIP was estimated using an in situ technique. The levels of supplemental DIP infused were .041, .082, and .124% BW/day. Controls received none. Following a 10-day adaptation, feed offered, feed refused, and total fecal output were measured for 7 days, in order to calculate intake response and digestibility coefficients. Results and Discussion Supplemental DIP exerted essentially no effect on forage or total OM intake, total OM digestion, or total digestible OM intake. Similarly, neither total NDF intake nor NDF digestibility were altered. We conclude that DIP was not significantly limiting the utilization of the Bermuda hay used in this study, in spite of the fact that the DIP in the Bermuda (about 8.3% of total digestible OM intake) was considerably less than the 11% previously demonstrated to maximize intake and digestion of lower quality (CP<7%) forages (such as winter tallgrass-prairie forage). The low level of DIP intake at which total diet intake and digestion were maximized is surprising and deserves additional evaluation. The Bermuda hay used in our study was of medium quality. Feeding Bermuda hay of lower quality (particularly with lower CP) might elicit a response to supplemental DIP. .120 4.83 aL = Linear, Q = Quadratic, C = Cubic. bStandard error of the mean (n=3). cDM = dry matter. dOM = organic matter. eDOMI = digestible organic matter intake. fOMD = organic matter digestion. gNDFD = neutral detergent fiber digestion. hDIPI = degradable intake protein intake. DIP (% BW) EFFECTS OF INCREASING AMOUNTS OF SUPPLEMENTAL SOYBEAN MEAL ON INTAKE AND DIGESTIBILITY OF TALLGRASS-PRAIRIE HAY C. P. Mathis, R. C. Cochran, J. S. Heldt, B. C. Woods, K. C. Olson, and G. L. Stokka Summary Twenty ruminally fistulated beef steers with free-choice access to prairie hay were used to evaluate the effect of increasing level of soybean meal (SBM) on forage intake and digestion. Forage intake, total organic matter intake, and organic matter digestion were enhanced with increasing level of SBM supplementation, although forage intake and digestion appeared to plateau at higher levels. The concomitant rises in intake and digestion as supplemental SBM increased resulted in an increase in total digestible organic matter intake, with the largest response to the initial increment of supplement. Introduction Prairie hay is a common roughage source for beef cattle throughout Kansas and the midwest. Previous research conducted at Kansas State University demonstrated that supplementation with degradable intake protein (DIP) dramatically improves intake and digestion of lowquality, tallgrass-prairie forage, and demonstrated the amount of DIP needed to maximize total digestible forage. However, in those preliminary studies, DIP was supplied in a purified form, sodium caseinate. Therefore, to link previous work to a more practical setting, potential feedstuffs high in DIP must be identified, and their response evaluated. The present study was conducted to evaluate the impact of increasing levels of soybean meal (SBM), an oilseed by-product containing a relatively high concentration of DIP, on prairie hay intake and digestion. Experimental Procedures Twenty ruminally fistulated beef steers (average body weight, 813 lb) were blocked by weight and assigned to one of five treatments to evaluate the effect of increasing level of highprotein SBM on forage intake and digestion. Each steer was offered prairie hay at 130% of average voluntary intake for the preceding 5-day period. The forage contained 69.4% NDF, and 5.3% CP, 49% of which was DIP (single-point enzyme assay). Supplemental SBM (9.8% NDF, 53.4% CP) was fed at 6:30 AM and steers were fed forage at 7:00 AM. Supplemental SBM was offered at .08, .16, .33, and .50% BW/day, which provided .029, .058, .116, and .175% BW/day of DIP. Controls recieved none. The SBM crude protein was assumed to be 66% DIP (1996 National Research Council; Nutrient Requirements of Beef Cattle). We also used a single-point enzyme system to provide an alternate estimate. Following a 14-day adaptation, feed offered, feed refused, and fecal output were measured for 7 days, and the information was used to monitor intake response and calculate digestibility coefficients. Results and Discussion Forage and total organic matter intakes (FOMI and TOMI, respectively) increased (P<.01) with increasing SBM supplementation (Table 1). However, FOMI appeared to plateau (P=.02) once the level of SBM supplementation reached .16% BW/day. However, TOMI continued to increase up to the highest level fed (.5% BW/day). Organic matter digestibility (OMD) also increased (P<.01) with increasing supplemental SBM up to the highest level. Fiber digestion (NDF digestion) responded similarly. The concomitant rises in TOMI and OMD as s u p p l e m e n t a l S B M increased resulted in an increase in TOMI. The largest proportional response was observed with the initial increment of supplement. Thereafter, the response was smaller, and once the .16% BW/day level was reached, appeared to be due predominately to higher levels of highly digestible SBM. If the table values are used for SBM DIP (i.e., 66%), then the total DIP intake is 8.4% of the TOMI for the .16% BW treatment. If the enzymatic estimate of SBM DIP is used (84% of CP), that value is about 9.4%. We suspect that the breakpoint in response (which should be indicative of maximal forage utilization) would fall close to these values. Effects of Increasing Amounts of Soybean Meal on DM and OM Intakes and Digestibility in Beef Steers Fed Tallgrass-Prairie Hay L a L = Linear, Q = Quadratic, C = Cubic. bStandard error of the mean (n=4). cDM = dry matter. dOM = organic matter. eDOMI = digestible organic matter intake. fOMD = organic matter digestion. gNDFD = neutral detergent fiber digestion. hDIPI = degradable intake protein intake; SBM DIP estimate from 1996 Beef NRC. Cattlemen’s Day 1998 IMPACT OF INCREASING AMOUNTS OF SUPPLEMENTAL HIGH-PROTEIN SOYBEAN MEAL ON PERFORMANCE OF RANGE BEEF COWS 1 C. P. Mathis, R. C. Cochran, B. C. Woods, J. S. Heldt, K. C. Olson, and D. M. Grieger Summary One hundred and twenty spring-calving Hereford × Angus cows grazing low-quality, tallgrass-prairie forage were fed 1.0, 1.5, 2.0, 2.5, 3.0, 4.0, 5.0, or 6.0 lb soybean meal (SBM) per head daily. SBM as a source of supplemental degradable intake protein (DIP) can be effective in maintaining cow body weight and body condition during the winter grazing season. Performance as measured by changes in body weight and condition score was maximized when cows received approximately 3.5 to 3.8 lb/day. Below this level, cows lost about 48 lb (about .4 units of BCS) for every 1 lb decrease in the amount of supplemental SBM. The effect of amount of supplemental SBM on calf performance was minimal. Introduction Protein supplementation to beef cattle grazing low-quality, tallgrass-prairie forage has been a long-standing practice. However, in recent years, the mechanisms by which that protein is utilized have become more clear. We now classify the protein that is degraded by microbes in the rumen as degradable intake protein (DIP) and the protein that escapes ruminal degradation and passes through the rumen to the small intestine without being altered as undegradable intake protein (UIP). Research at Kansas State University demonstrates that DIP is the first-limiting nutrient for optimal intake and utilization of low-quality forage. However, that research was conducted by supplementing DIP in a purified form (sodium caseinate). Applying that research under production conditions requires identification of potential protein supplements that are high in DIP. Soybean meal (SBM), in which 66% of the protein is DIP, is a good candidate. The objectives of this study were to identify the level of SBM that elicits maximum performance response and to define the rate of performance decline below the maximum response. Experimental Procedures A performance study was conducted during winter 1996-97 to evaluate the impact of level of supplemental SBM on body weight, body condition, and pregnancy rate of spring-calving beef cows grazing low-quality, tallgrass-prairie forage. Forage samples clipped from the pastures contained 76% NDF and 2.7% CP, with 49% of the CP as DIP. DIP was estimated using a single-point enzyme assay. The SBM was 10.1% NDF and 53.9% CP, with 66% of the CP as DIP (1996 Beef NRC). One hundred and twenty Hereford × Angus cows (average initial body weight, 1141 lb; average initial body condition score, 5.3) were allotted randomly to one of three pastures. Within each pasture, cows were assigned to one of eight levels of supplemental SBM; 1.0, 1.5, 2.0, 2.5, 3.0, 4.0, 1Appreciation is expressed to the Bunge Corporation for providing the soybean meal used and to Gary Ritter and Wayne Adolph for their assistance. 5.0, and 6.0 lb/head/day as-fed. Cattle in each pasture were gathered daily, sorted into their respective treatments, group-fed their supplement, and then returned to pasture. The treatment period began December 2, 1996 and was terminated on February 10, 1997, which was the first day of the calving season. After the calving season began, all cows were fed 3.8 lb/head/day until they calved. Following parturition, cows were fed 10 lb/head/day of alfalfa until sufficient new grass growth was available in the spring. Body weight and condition were measured at approximately 1-month intervals until the beginning of the calving season. Thus, measurements were obtained on December 2, January 6, and February 10, with additional measures postcalving (within 48 h after calving), shortly before the beginning of the breeding season (May 8), and at weaning (October 1 ). Cows were bred by natural service to Angus bulls. Results and Discussion Losses in cow body weight (BW) and body condition score (BCS) through the beginning of the calving season (Table 1) were reduced (linear P<.01) by increasing the level of supplemental soybean meal (SBM); however, both BW and BCS showed a clear plateau (quadratic P<.01). Maximal BW response to supplemental SBM was achieved at approximately 3.5 lb/head/ day, and BCS response was maximized at approximately 3.8 lb/head/day. Feeding SBM above these levels yielded no further reduction in BW or BCS loss. Below this point of maximal response (3.5 to 3.8 lb SBM/head/day), each 1 lb decrease in SBM fed daily resulted in a 48 lb reduction in BW and a .4 unit decrease in BCS. The level of SBM fed from the beginning of the winter grazing season until the beginning of the calving season had no affect on calf birth date (Table 2; P>.52) or calf average daily gain (P>.43). However, there was a trend for level of supplemental SBM to affect calf birth weight (linear P=.14; quadratic P=.16) and weaning weight (quadratic P=.12). Pregnancy rate not influenced significantly (P=.51). Knowledge of the amount of supplemental SBM at which performance is maximized and the rate of decline below that maximum can be used as a rough guideline for determining the amount of supplemental SBM necessary to achieve a specified level of BW or BCS change in spring-calving beef cows grazing winter range. Effects of Increasing Amounts of Supplemental Soybean Meal (SBM) on Cumulative and Period Body Weight (BW) and Condition Scorea (BCS) Change, Pregnancy Rate, and Calf Performance of Beef Cows Grazing Dormant, Tallgrass-Prairie Forage EFFECT OF SUPPLEMENTAL CARBOHYDRATE SOURCE ON THE UTILIZATION OF LOW-QUALITY TALLGRASS-PRAIRIE HAY BY BEEF STEERS J. S. Heldt, R. C. Cochran, C. G. Farmer, C. P. Mathis, E. C. Titgemeyer, and T. G. Nagaraja Summary Twenty ruminally fistulated steers were used in two experiments to evaluate the effects of supplemental carbohydrate source (starch, glucose, fructose, or sucrose) fed at .3% BW/day on the utilization of low-quality tallgrass-prairie hay. In Experiment 1, all supplemental carbohydrates were fed with a low level of supplemental degradable intake protein. In Experiment 2, the level of supplemental degradable intake protein was high. Intake of the tallgrass-prairie hay was not affected significantly by supplementation in either experiment, but as a result of the added carbohydrate, total intake was increased. When supplemental protein intake was inadequate, supplemental carbohydrates depressed digestion, but when supplemental protein was higher, fiber digestion was not depressed. Because of increased total intake (forage plus supplement) and increased digestion in Experiment 2, total digestible organic matter intake was greater in the supplemented animals, with little difference among carbohydrate sources. (Key Words: Steers, Forage, Starch, Sugar.) Introduction Feeding supplements with a high concentration of degradable intake protein (DIP) has been shown to increase intake and digestion of low-quality forages. In contrast, the effects of feeding large amounts of highly digestible carbohydrate (CHO) may depend on the source of CHO and the amount of DIP provided. Supplemental starch has been shown to decrease the utilization of low-quality forages, whereas nonstarch CHO sources such as fiber and sugars have produced variable results. Our study was designed to provide additional insight into the specific effects of supplemental starch and various sugars, when fed with different amounts of DIP, on intake and digestion of lowquality tallgrass-prairie hay. Experimental Procedures Twenty Hereford × Angus steers with ruminal fistulas were housed in individual tie stalls and used in two experiments. In both experiments, steers had free-choice access to low-quality tallgrassprairie hay (5.2% CP and 72.7% NDF in Exp. 1 and 5.2% CP and 76.0% NDF in Exp. 2). Steers were randomly assigned to treatments at the beginning of each experiment. Treatments were either no-supplement negative control (NC) or supplemental starch, glucose (supplied as dextrose), fructose, or sucrose fed at .30% BW/daily. Sucrose is a disaccharide composed of two monosaccharides, glucose and fructose. We were interested in sugars because of their presence in molasses-based liquid supplements and blocks. Supplemented steers also received degradable intake protein (DIP; sodium caseinate) fed at .031% BW/day in Exp. 1 and .122% BW/day in Exp. 2. Both experiments included a 14-day adaptation period followed by a 7-day intake and fecal collection period. Fecal grab samples were collected every day during the collection period and analyzed for acid detergent insoluble ash, which served as an internal marker to determine total fecal output. Feed offered, feed refused, and fecal output were used to monitor intake response and calculate organic matter (OM) and neutral detergent fiber (NDF) digestibilities. Results and Discussion Supplements did not significantly stimulate forage intake compared with the negative control in either experiment (Tables 1 and 2). This was expected when DIP was low (Exp. 1) but not when supplemental DIP was higher (Exp. 2). Because forage intake was similar among treatments, total intake was obviously increased by provision of the supplement. When limited DIP was provided (Exp. 1), fiber digestion was depressed by supplemental carbohydrate, particularly glucose and sucrose. However, because the supplemental carbohydrate was more digestible than the basal forage, total diet digestibilities for the supple- mented groups did not differ from that of the negative control. In contrast, when a higher level of DIP was fed in Exp. 2, supplemental carbohydrates had no negative effect on fiber digestion. In fact, fiber digestion increased when glucose or fructose was fed. Because fiber digestion was not harmed in Exp. 2, the supplemented groups all had a higher total diet digestion than the negative control. When the combined effects of intake and digestion were considered, total digestible OM intake increased with carbohydrate supplementation in both experiments. However, little difference occurred among the different carbohydrate sources. In contrast to supplemental DIP, which can stimulate forage intake and digestion, the response to supplemental carbohydrate sources appeared to be limited mostly to the nutrients provided in the supplements themselves. Intake, g/kg BW.75 Forage OMa Total OM Digestible OM Intake, Digestibility, % OM NDFb a OM = Organic matter. b NDF = Neutral detergent fiber. c,d Least squares means in a row with uncommon superscripts differ (P#.06). NDF = Neutral detergent fiber. c,d,e,f Least squares means in a row with uncommon superscripts differ (P ≤ .06). Carbohydrates Fed with High Degradable Intake Protein Control Starch Glucose Fructose Sucrose SEM EFFECTS OF VARIOUS CARBOHYDRATE SOURCES ON THE UTILIZATION OF LOW-QUALITY TALLGRASSPRAIRIE HAY IN CONTINUOUS CULTURE J. S. Heldt, R. C. Cochran, C. P. Mathis, E. C. Titgemeyer, and T. G. Nagaraja Summary We evaluated the effects of supplemental carbohydrate sources on the utilization of lowquality forage in continuous “artificial rumen” culture. Providing readily digestible carbohydrates (starch, glucose, and fiber) did not improve total diet digestion. In fact, starch and glucose depressed fiber digestion. Response to other simple sugars was variable. (Key Words: Digestion, Carbohydrate, Forage, Continuous Culture.) Introduction Feeding supplements with a large amount of carbohydrate (CHO) can have different effects on forage utilization, depending on the source used. Supplemental starch has decreased utilization of low-quality forages, whereas nonstarch CHO sources such as fiber and glucose have had both positive and negative effects. Similar results were observed in recent research conducted at KSU, although the impact of CHO source tended to be dependent on the amount of supplemental degradable intake protein provided. The present study was designed to provide additional insight into the specific effects of various CHO sources on digestion and fermentation characteristics of lowquality tallgrass-prairie hay. Experimental Procedures In experiment 1, eight dual-flow contin- uousculture flasks were used for two periods in a randomized complete block design. The four dietary treatments were forage only (negative control; NC) and forage plus either starch; glucose (supplied as commercial dextrose); or digestible fiber (FIBER; supplied as alkaline hydrogen peroxide-treated oat hulls). In experiment 2, nine dual-flow continuous-culture flasks were used for three periods in a randomized complete block design. The nine dietary treatments were forage only (NC), and forage plus pentoses (arabinose and xylose); hexoses (glucose, fructose, and galactose); or disaccharides (lactose, maltose, and sucrose). The same prairie hay (5.4% CP and 65.7% NDF) was used in both experiments. The experimental periods consisted of 5 days of adaptation and 3 days of sampling. The continuous-culture fermenters (554 mL) were designed to simulate ruminal fermentation and were each fed 16 g DM/day with a forage-to-CHO ratio of 4:1 (g DM/g DM). The fermenters contained ruminal microorganisms harvested from a ruminally cannulated steer maintained on a low-quality, prairie-hay diet. They were held at rumen temperature, and pH was maintained within levels that allowed for continuous growth and digestion by the microorganisms. A constant amount of nitrogen (urea) was infused into each flask each day as part of the buffer solution. Results and Discussion The source of supplemental CHO did not affect (P$.49) either apparent or true organic matter digestion (Table 1). However, starch and dextrose tended (P#.11) to decrease neutral detergent fiber (NDF) digestion compared to NC and FIBER. Part of the reason why supplemental FIBER may not have affected NDF digestion was that the treated oat hulls were very digestible fiber sources. All supplemental CHO sources decreased (P#.10) flask pH below 6.2, which may have depressed forage digestion (Table 2). Including starch and dextrose both increased (P#.08) total VFA concentration and decreased (P#.10) the molar proportion of acetate, indicative of the fermentation of a highly available CHO. Propionate, acetate: propionate ratio, and butyrate were unaffected (P$.10) by supplemental CHO. The quantity of ammonia detected in the ruminal fluid was less than that for NC when starch was supplemented and was intermediate and similar to that for NC with the dextrose and fiber treatments. In experiment 2 (Table 2), diet digestion was greater (P#.10) when sucrose was supplemented compared to NC. Most of the remaining supplemental sugars resulted in digestibilities intermediate between those for NC and sucrose. The only exceptions were arabinose and lactose, which provided values lower than sucrose. No differences (P$.10) occurred in NDF digestion between the pentoses or among the disaccharides. However, within the hexoses, glucose decreased (P#.10) NDF digestion compared to NC, whereas galactose and fructose did not. Two of the eight supplemental sugars decreased (P#.10) flask pH (Table 4) and four increased total VFA concentration compared with NC. Also, all supplemental sugars, except the pentoses, decreased acetate and increased butyrate proportions compared with NC. It is apparent that supplemental sugars differ in their effects on forage utilization. Clarifying those differences is necessary to effectively plan their incorporation into supplementation programs. Apparent OMc True OM NDFd a,bMeans in a row with uncommon superscripts differ (P # .10). cOM = organic matter. dNDF = neutral detergent fiber. Digestion, % Starch EARLY DETECTION OF PROBLEM IMPLANTS USING INFRARED THERMOGRAPHY1 M. F. Spire 2, J. C. Galland 2, and J. S. Drouillard Thermal imaging of feedlot cattle ears is a noninvasive diagnostic tool that aids in identifying properly placed or abscessed growth-promoting implants. Thirty-two calves were used to determine if abscessed and normal, functional implants could be identified and differentiated using infrared thermography. Infrared images were taken at implantation on days 2, 4, 7, 14, and 21 after implantation. Abscessed implants were easily identified. Use of thermal imaging can verify implant administration and, thus, has the potential to immediately impact feedlot quality assurance programs. Introduction Problem implants in fed cattle result in economic losses ranging from $2.70 to $4.94 per head implanted. Much of the observed loss is attributed to abscessed implants, missing implants and improper implantation technique that causes variation in the surface area of the implant. Factors affecting implant surface area will alter product release. The full extent of the problem rate can be assessed only by observing 100% of implant sites 7 to 21 days after implanting. The repeated handling of feedlot cattle necessary for 100% inspection is a major drawback for correcting problem implants. Infrared thermography can remotely and non-invasively detect problem implants. This experiment was designed to determine if variation over time exists in the thermographic appearance of ears implanted with normally functioning growth-promotant implants and improperly functioning abscessed implants. A total of 32 calves was assigned randomly to one of two treatment groups. Group A (normal implant) received a Synovex-Plus implant following disinfection of the ear. Group B (abscessed implant) received a Synovex-Plus implant in which the ear and the implant needle were contaminated with fecal material. Half of each treatment group received the implant in the left ear. The remaining calves were implanted in the right ear. The nonimplanted ear on each calf served as the control for thermographic comparisons. Thermographic images of the front and back of the ears of each calf were obtained on trial days 0, 2, 4, 7, 14, and 21 using an Amber Engineering Radiance PM, high resolution, shortwave length (3-5 Fm), radiometric, infrared, thermal-imaging unit. All thermographic images were taken from a 1The authors express their appreciation to Ft. Dodge Animal Health for providing grant support of this research. 2Food Animal Health and Management Center, College of Veterinary Medicine distance of about 3 ft, with the animal in standing restraint in a hydraulic squeeze chute. Temperature measurements were determined from an area on the front of the ear or on the back of the ear at the base, middle, and tip. A randomized, complete block design was used to investigate the thermographic patterns of cattle with normal, functional growth-promotant ear implants vs. cattle with abscessed implants. Repeated measures analysis of variance was used to determine the relationships among distribution of temperature for the entire ear and the zone surrounding the implant (the response variables) and treatment; pen; treatment×pen interaction; time, treatment×time interaction; and side (ear) of placement (the explanatory variables) for the front, back, and front/back of each implanted ear. Mean temperatures between normal implants vs. abscessed implants were contrasted. Results and Discussion Images of the front or back of the ear were comparable on postimplantation days 2, 4, 7, and 14 when used to differentiate abscessed ears from the nonimplanted ear. The side (left or right) of implantation did not affect detection of abscessed vs. functional implants. Thermal imaging the front of the ear detected the difference between an abscessed implant and a functional implant on postimplantation days 2, 4, 7, and 14 (P<.001). Abscessed implanted ears imaged from the front were found to be 32.9EF ± 5.02 warmer than functional implanted ears o n day 4. Image of the back of the ear detected temperature differences between abscessed and functional implanted ears on postimplantation days 4 and 7 (P<.001). Thermography also detected temperature differences between functional implanted ears and nonimplanted control ears on day 2 postimplantation using images of either the front or back and on day 4 when the ear was viewed from the rear. Figure 1 demonstrates the least square mean temperatures of abscessed implanted ears, functional implanted ears, and nonimplanted control ears on day 4 postimplantation at various locations on the ear. Thermal imaging is a remote, noninvasive tool capable of detecting temperature differences between functional implanted, abscessed implanted, and nonimplanted ears. Thermal imaging within the first 2 weeks after arrival in the feedyard or at reimplanting after 60-70 days is a useful tool that can aid in identifying properly placed or abscessed growth-promoting implants placed in the ears of feedlot cattle. Its use to assess the efficiency of implanting by processing crews has the potential to immediately impact quality assurance programs. Far greater potential lies in the ability of thermal imaging to differentiate between functional implants and nonfunctional (abscessed or missing) implants in the pen (Figure 2). Once identified, cattle with nonfunctional implants can be reimplanted and returned immediately to their home pen with a functional implant. Front Tip Middle Location on Ear Base COMPARISON OF IMPLANTS IN GRAZING HEIFERS AND CARRYOVER EFFECTS ON FINISHING GAINS AND CARCASS TRAITS F. K. Brazle 1 Summary Crossbred yearling heifers were allotted randomly to three grazing implant treatments: 1) control (CONT), 2) Component® E-H (CEH), and 3)Ralgro® (RAL). After grazing native grass for 74 days, the heifers were transported to a western Kansas feedlot. All heifers were implanted with Synovex-H® upon arrival at the feedlot and were reimplanted 70 days later with Finaplix-H®. The CEH heifers gained faster while on grass (P<.10) and in the feedlot than the RAL heifers. The CEH heifers had heavier carcasses than RAL heifers. Control heifers had the largest ribeyes. Other carcass traits, including USDA quality grade, were not influenced by pasture treatment. In this study, administration of CEH to heifers grazing native grass optimized overall performance when combined with the feedlot implants (Synovex-H and Finaplix-H). (Key Words: Implants, Heifers, Feedlot). Current implanting strategies involve the use of certain implants in specific phases of the cattle production cycle. Determining the relationship of implants used during the grazing phase to the trenbolon acetate-based implants employed in finishing programs might allow for the use of different implant combinations in growing/finishing systems. The objectives of this study were to compare the effectiveness of Component E-H (CEH) and Ralgro (RAL) when administered in a grazing program and to calculate their effects on subsequent feedlot and carcass performance. Experimental Procedures Two hundred fifty-eight crossbred yearling heifers were allotted randomly to three implant treatments: 1) control (CON), 2) Component E-H (CEH), and 3) 36 mg Ralgro (RAL). The heifers were implanted according to manufacturers’ recommendations and weighed individually before being grazed on Flint Hills native grass pastures. Equal numbers of heifers in each implant group were allotted randomly to two pastures. All heifers were grazed for 74 days, then weighed individually early in the morning and shipped 300 miles to a commercial feedlot near Garden City, where they all were fed in one pen for 120 days. At the feedlot, all heifers were implanted initially with Synovex-H and reimplanted 70 days later with Finaplix-H. The heifers were slaughtered at a commercial packing plant, and carcass data were collected. 1Extension Specialist, Livestock Production, Southeast Kansas. Results and Discussion The CEH heifers gained 19.6% faster than control and 8.8% faster (P<.10) than RAL heifers during the grazing period. The RAL heifers gained less (P<.10) than the other groups during the feedlot phase. However, no differences occurred in feedlot gain between the CONT and CEH heifers (Table 1). The CEH heifers had heavier (P<.10) carcasses than RAL heifers, whereas those of controls were intermediate. In this study, grazing heifers implanted with Component EH, when followed in the feedlot with Synovex-H and Finaplix-H, performed better overall than those implanted with Ralgro. The control heifers had the largest ribeyes, when expressed on either an actual or carcass weight-adjusted basis. This was not expected and either may be an artifact of cattle allotment or due to feedlot implants reacting differently in unimplanted cattle. At the time of implanting before grazing, the heifers were palpated for old implants, and only eight were found. Other carcass traits, including backfat thickness, KPH fat percentage, and USDA quality grade, were not affected by pasture implant treatments. Effects of Implanting Heifers on Grazing Gains and Subsequent Feedlot and Carcass Performance Control Component E-H Ralgro SE Item No. heifers Starting wt, lb Daily gain, lb Grazing, 74 d Finishing, 120 d Results Hot carcass wt, lb Backfat, in. Ribeye area, sq. in. Ribeye area/cwt carcass wt KPH fat, % USDA % Choice abcMeans in the same row with unlike superscripts are different (P<.10). 87 517 86 515 EFFECTS OF FEEDING RUMENSIN® IN A MINERAL MIXTURE ON STEERS GRAZING NATIVE GRASS PASTURES F. K. Brazle 1 and S. B. Laudert 2 Summary Four hundred sixty-nine English and Continental cross yearling steers grazed on native grass pastures over a 2-year period. Rumensin® was added (1,620 g/ton) to the mineral mixture in half of the pastures. Some of the pastures were used from April 23 to July 15 and the remainder from April 23 to August 15. The pooled data for the grazing periods indicated that Rumensinsupplemented steers gained 7.7% faster (P<.05) and consumed 32% less mineral (P<.05) compared to the control steers. (Key Words: Rumensin, Native Grass, Mineral.) Feed additives used to improve gains of stocker cattle grazing native grass are normally added to the mineral mixtures, resulting in changes in mineral consumption. The objective of this study was to determine the effect of Rumensin® on weight gain and mineral intake of steers grazing native grass pastures from April 23 to either July 15 or August 15. Four hundred sixty-nine English and Continental Cross yearling steers grazed on native grass pastures. In 1996, four pastures were used (2 acres/head for 83 days) from April 23 to July 15, and four pastures were used (3 acres/head for 114 days) from April 23 to August 15. In 1997, four pastures were used (2 acres/head for 83 days) from April 23 to July 15, and two pastures were used (3 acres/head for 114 days) from April 23 to August 15. Within each pasture replication, steers were allotted randomly to two treatments: a mineral mixture without Rumensin (control) or a mineral mixture with Rumensin80 added at 1620 g/ton, replacing a processed grain by-product (Table 1). Mineral consumption was monitored weekly. Results and Discussion The performance data for the steers grazing to July 15 are shown in Table 2. Steers with access to the Rumensin mineral mixture tended to gain more, but the difference was not significant. Additionally, the Rumensinsupplemented steers consumed less mineral (P<.03) than controls. The Rumensin-supplemented steers that grazed to August 15 (Table 3) had significantly higher gains (P<.08) than the control steers. The pooled data (across years and grazing periods) show a gain response of .19 lb/head/day (P<.05) for steers receiving Rumensin in a mineral mixture and grazing native grass pasture (Table 4). The average Rumensin intake was 170 mg/head/day. The 1Extension Specialist, Livestock Production, Southwest Kansas. 2Elanco Animal Health, Garden City, Kansas. presence of Rumensin in mineral mixtures reduced mineral intake to 3.4 oz per day vs. 5.0 oz per day for control. These data show that mineral mixtures containing Rumensin improve gains. The reduction in mineral intake may offset some of the cost of the mineral. Control cattle grazing to July 15 consumed an average of 5.3 oz of mineral daily vs. an average of 4.6 oz daily for those grazing to August 15. Corresponding intakes for cattle receiving Rumensin were 3.4 and 3.3 oz. Cattle normally have high salt and/or mineral consumption early in the season, but consumption declines as the grass matures, which would explain the difference in mineral consumption for control steers. Intake of mineral mixtures containing Rumensin appearred to be more consistent from week to week. Formulation of Rumensin Mineral Mixture abMeans in the same row with unlike superscripts are different (P<.03). SE .107 .464 Effects of Mineral Mixture with Rumensin on ADG and Mineral Consumption to Steers Grazing Native Grass (3 acres/head/August 15, 1996-97) abMeans in the same row with unlike superscripts are different (P<08). Overall Effects of a Mineral Mixture with Rumensin on Steers Grazing Native Grass to Either July 15 or August 15 (1996-97) abMeans in the same row with unlike superscripts are different (P<.05). EFFECTS OF REVALOR-G®, RALGRO®, AND SYNOVEX-H® ON THE PERFORMANCE OF STOCKER HEIFERS GRAZING IRRIGATED RYE PASTURE 1 D. A. Blasi and G. L. Kuhl A 151-day field study was conducted to compare three anabolic implants for promoting weight gain in stocker heifers grazing center pivot-irrigated pastures of winter rye. Three hundred previously nonimplanted heifers averaging 421 lb were allotted to one of four treatments: 1) no implant-control (NC), 2) Ralgro® (RAL), 3) Revalor-G® (REV-G) and 4) Synovex-H® (SYN-H). Heifers were weighed at monthly intervals to evaluate the growth response curve of each implant type over time relative to controls. Only during the first 32-day period after implantation did heifers implanted with REVG gain significantly faster (P<.05) than NC. All implant groups responded similarly (P>.05) during the next three monthly weigh periods. During the last period (day 124151), SYN-H heifers gained faster (P<.05) than all other treatments. Over the entire 151-day study, daily gains (lb/day) averaged as follows: NC, 1.50; RAL, 1.58; REV-G, 1.64; and SYN-H, 1.79. All implant types except RAL significantly improved gain (P<.05) compared to NC. Although no significant difference (P>.24) occurred between RAL and REV-G, SYN-H-implanted heifers gained faster (P<.05) than the other implant groups over the 151-day grazing season. (Key Words: Growth Implant, Revalor-G, Ralgro, Synovex-H, Heifers, Rye Pasture.) The use of estrogenic implants to enhance the performance of grazing stockers has been adopted widely by cattle producers. Revalor-G is a newly approved anabolic agent for grazing cattle containing trenbolone acetate (a potent testosterone analog) and estrogen. However, no published research is available comparing REV-G to traditional estrogenic implants for heifers grazing winter rye pasture. Our objective was to evaluate the relative effectiveness of Revalor-G (40 mg trenbolone acetate and 8 mg estradiol), Ralgro (36 mg zeranol), and Synovex-H (20 mg estradiol benzoate and 200 mg testosterone propionate), in improving weight gain of yearling heifers grazing irrigated, winter rye pasture. Three hundred and seventy-five predominantly British crossbred heifers were purchased in Mississippi and assembled near Pratt, KS for 4 weeks prior to trial initiation. Upon arrival, they were vaccinated against common viral and bacterial diseases. At trial initiation, all heifers were weighed individu1Sincere appreciation is expressed to Great Plains Cattle, Pratt, Kansas for providing cattle, facilities, and assistance, and to Hoeshst-Rouseel Vet for financial support. ally (unshrunk) on 2 consecutive days, identified with a tag in each ear, dewormed, and checked for evidence of prior implants. Then, 300 uniform heifers were selected and allotted randomly to four treatments, within weight blocks, and implanted according to manufacturers’ recommendations. The treatments were: 1) no implant-control (NC), 2) Ralgro (RAL), 3) Revalor-G (REV-G), and 4) Synovex-H (SYN-H). For each of the remaining weigh days (days 32, 60, 92, 123, and 151), heifers were gathered, placed in drylot, and fed hay and alfalfa/wheat middling (AWM) pellets for 1 day before individual weights were obtained. All heifers grazed predominantly winter rye pasture during the 151-day trial. Heifers were assigned randomly to one of two rye pastures with center pivot irrigation. Equal pounds of live cattle were stocked per circle. However, inclement winter weather and insufficient rye forage necessitated feeding supplemental alfalfa and AWM pellets in addition to either rye or alfalfa hay during a 45-day period in December and January. Four heifers were removed because of health problems unrelated to implant treatment. Individual animal was the experimental unit for statistical analysis of weight gain data. Results and Discussion Table 1 presents heifer daily gains by implant treatment and monthly weigh period. Performance of RAL heifers was not significantly different (P>.05) than that of NC or REV-G heifers at any weigh period. All implant types produced similar (P>.05) growth responses during the second (days 33-60), third (day 61-92), and fourth (days 93-123) weigh periods. SYN-H heifers gained significantly faster (P<.05) than heifers in all other implant treatments between days 124 and 151 and over the entire 151day trial. Figure 1 presents the cumulative growth response of heifers to each implant type relative to nonimplanted controls over the course of the 151-day study. Both the REVG and SYN-H-implanted heifers gained rapidly early in the study relative to the NC treatment. However, the anabolic response from each implant was different over the course of the study. For SYN-H, a sustained growth response was observed above the NC treatment that did not vary much throughout the 151-day experiment. This suggests that the payout response of SYN-H implants may last at least 151 days. In contrast, the REVG implant demonstrated a classic "half-life" response relative to the NC treatment over the 151-day study. Finally, the response of heifers implanted with RAL was initially very slow and never reached the growth trajectory demonstrated by the other two implants. Heifer Daily Gain (lb) by Monthly Weigh the Periodb NC RAL REV-G SYN-H 75 75 73 73 1.02cd 1.23de a NC= Negative Control; RAL = Ralgro®, REV-G = Revalor-G®, SYN-H = Synovex-H®. All implants administered on day 1. bFirst = First 32-day weigh period from 11/18/96 to 12/20/96; Second = 28-day period from 12/20/96 to 01/17/97;Third=32-day periodfrom 01/17/97 to 02/18/97; Fourth=3l-day period from 02/18/97 to 03/21/97; Fifth = 28-day period from 03/21/97 to 04/18/97. c,d,eValues in columns not sharing a common superscript are different (P<.05). Cumulative Day of Study Cumulative Growth Responses of Heifers to Anabolic Implants Relative to Nonimplanted Controls during the Grazing Season. Cattlemen’s Day 1998 CHARACTERISTICS OF PELLETED WHEAT MIDDLINGS THAT AFFECT SUMMER STORAGE C. R. Reed 1, D. M. Trigo-Stockli 1, D. A. Blasi, and F. J. Fairchild 1 Summary Pelleted wheat middlings samples were collected from four Kansas flour mills in March, April, and May, 1997 to characterize their moisture content and bulk density as they would be purchased directly from the mills by a livestock producer. The average moisture content of pelleted wheat middlings was 14% as they left the mills but declined during the spring to 13.6%. Pellets purchased from Kansas mills during the summer months are likely to contain 13.0 to 13.5% moisture. The average bulk density was approximately 40 lb/ft3, which is equivalent to about 50 lb/bu. Based on the equilibrium moisture contents determined from the collected samples, if air at typical Kansas summertime temperatures is above 65% relative humidity, pellets will absorb moisture during storage. (Key Words: Wheat Middlings, Storage.) Wheat middlings (WM) are by-products of flour milling and have nutritional value in cattle rations. Ground WM are difficult to handle and quickly lose their flowability in bulk bins. However, pelleted WM are gaining acceptance with cattle feeders because of greater density and improved handling and flowability characteristics. During summer months, the price of pelleted WM declines, thereby creating an excellent feed ingredient value. However, when pelleted WM are stored on-farm through the summer months, many Kansas producers have observed heating, which has resulted in caking, discoloration, and loss of flowability (Blasi et al., 1997 Cattlemens Day Report of Progress, p 37). This study was initiated in March, 1997 to investigate the characteristics of pelleted WM that relate to their storability, especially during summer months. Our objective was to describe moisture and bulk density characteristics of the pelleted WM as they would be purchased from Kansas mills. Our longterm goal is to develop practical recommendations for on-farm storage of WM during summer months. Pelleted WM were collected from four Kansas mills on four occasions in March, April, and May, 1997. Sealable containers were supplied to the millers with instructions that samples should be taken randomly from the pellet stream on three occasions during a selected day. The samples, weighing 30 to 80 lb each, were sealed, identified, and collected on the following day. Thus, the pellets collected were no more than one day old, and were to be representative of pellets purchased directly by livestock producers. They were transported to a university labo1Department of Grain Science and Industry. ratory, where portions for moisture content and equilibrium moisture content were removed immediately, sealed, and stored at 40EF for later analysis. Moisture content (MC) was determined by a two-step air-oven method, and bulk density (BD) was determined with a 1-cubic-meter container. To determine the relationship between the air temperature and moisture content and the tendency of the WM to gain or lose moisture (equilibrium moisture content), small quantities of pellets were weighed precisely and placed in sealed chambers over saturated salt solutions that produce known relative humidities. The sealed chambers then were placed in controlled temperature rooms at 75EF or 85EF, where the weight of the pellets was checked periodically until no change was observed over several days. The pellet moisture content at this equilibrium condition then was determined. Results and Discussion Forty-one samples of 1/4 in. and 3/4 in. pelleted WM were collected from Kansas mills. The average BD of the two types of pellets was not noticeably different and ranged from 37.7 to 42.2 lb/ft3, with an average of 39.9 ± 0.9 lb/ft3 (Table 1). Most pelleted WM, regardless of the sampling time, weighed 38 to 41 lb/ft3, which is equivalent to approximately 50 lb/bu. In contrast, the ground middlings from which the pellets were manufactured weighed only about 20 lb/ft3. The overall average MC of the pellets was 14.0±0.5 %, and individual samples ranged from 12.8 % to 14.9 %. The MCs of the 3/4 in. pellets showed the greatest variability between sampling times. However, they contained about the same average MC as the smaller pellets. All pellets, regardless of size, were about 1% wetter than the ground middlings from which they were manufactured. As the ambient air warmed during the spring, the pellets arrived drier, with the average MC in May being 0.4 percent lower than the overall average. This trend continued into the summer. In August, we received pelleted WM for a separate study that contained only 13.3 % MC. Thus, WM pellets purchased from Kansas mills in June, July, or August likely will contain 13.0 to 13.5 % MC. WM pellets swell and soften significantly when they gain moisture, losing their ability to flow. Storage practices must ensure that moisture is not transferred from the air to the pellets. Pelleted WM at 13.5% MC are in equilibrium with air containing 68% relative humidity (RH) at 75EF and with air contain- ing 69% RH at 85EF. (Figure 1). This indicates that in air at the temperature range encountered during summer storage (60EF - 95EF), pellets will absorb moisture if RH is greater than 65%. Studies currently underway will allow the development of specific recommendations for aeration management to minimize mold growth and maintain maximum pellet flowability. Observed Equilibrium Moisture Content of Pelleted Wheat Middlings at 75°F and 85°F. Cattlemen’s Day 1998 BEEF CATTLE LAGOON SEEPAGE J. P. Murphy 1 and J. P. Harner 1 Most compacted soils can be used for lagoon liners to achieve seepage guidelines established by the Kansas Department of Health and Environment. (Key Words: Lagoon Seepage, Permeability, Soil Lagoon Liner.) The protection of surface and groundwater and the utilization or disposal of animal waste are the primary functions of waste storage ponds and treatment lagoons. However, seepage from these structures creates risks of pollution to surface water and underground aquifers. The permeability of the soil in the boundaries of a constructed waste treatment lagoon or waste storage pond strongly affects the potential for downward or lateral seepage of the stored wastes. Research has shown that many natural soils on the boundaries of waste treatment lagoons and waste storage ponds will seal at least partially as a result of physical, chemical, and biological processes. Suspended solids settle out of suspension and physically clog the pores of the soil mass. Anaerobic bacteria produce by-products that accumulate at the soil-water interface and reinforce the seal. Soil structure also can be altered as bacteria metabolize organic material. Chemicals in animal waste, such as salts, can disperse soil, which also may reduce seepage. Research has shown that soil permeability can be decreased by several orders of magnitude in a few weeks following contact with animal waste in a storage pond or treatment lagoon. The physical clogging of the soil is considered to be a function of the type of waste; the percent total solids in the waste; and the permeability, size, and geometry of soil pores. Until recently, research has focused on total solids of the waste as the most important factor in the physical sealing process. However, research published in the late 1980's has shown convincingly that a soil's equivalent pore size computed as a function of particle size distribution and porosity is probably more important. Although research has shown that permeability in all soils will decrease from 1 to 3 orders of magnitude because of manure sealing, this sealing alone probably will not provide enough protection against excessive seepage and groundwater contamination for soils with a very high initial permeability. Other research has demonstrated that for soils with clay contents exceeding 5 percent for ruminant or 15 percent for monogastric animal manure, a final permeability of 10-6 to 10-7 cm/sec usually results from manure sealing. Clay content is defined as the percent by dry weight of a soil that is smaller than 2 microns (0.002 mm) and is roughly equivalent to the percentage of soil that will pass through a No. 200 seive. Site Investigation 1Department of Biological and Agricultural Engineering. An on-site investigation of a potential waste storage site should include: evaluating soils, bedrock, groundwater, climatic conditions, and local water uses, to provide insight into the potential impact of the site on groundwater resources. Data should include the presence of any water wells or any other water supply sources, depth to the seasonal high water table, general ground water gradient, general geology of the site, and depth to bedrock, if applicable. Determining the intensity of any detailed site investigation is the joint responsibility of the designer and the person who has authority to approve the engineering job. The intensity of investigation required depends on past experience in a given area, the types of soils and variability of the soil deposits, the size of the structure, the environmental sensitivity, and an assessment of the associated risks involved. State and local laws should be followed in all cases. The subsurface investigation can employ auger holes, dozer pits, or backhoe pits. The investigation should extend to at least 2 feet below the planned bottom of the excavation. A site investigation can include field permeability testing and taking samples for laboratory testing, or it can be limited to field classification of the soils. Information from the site investigation should be documented and included in the design documentation. When logging soils from auger holes, always consider that mixing will occur and can obscure the presence of cleaner sand or gravel lenses. Pits and trenches expose more of the foundation, which is helpful in detecting small, but important, lenses of permeable soil. Always use safety rules around trenches. Soil mechanics laboratories of the Natural Resources Conservation Service (NRCS) have a database of permeability tests performed on over 1,100 compacted soil samples. Experienced NRCS engineers have analyzed these data and correlated permeability rates with soil index properties and degree of compaction. Based on this analysis, Table 1 (from NRCS Technical Note 716) has been developed to provide general guidance on the probable permeability characteristics of soils. The grouping is based on the percent fines (percent by dry weight finer than the #200 sieve, roughly equivalent to percent clay) and a plasticity index. This index represents the range of moisture contents at which a soil remains cohesive. Table 2 summarizes a total of 1,161 NRCS tests. Where tests are shown at 85 to 90% of maximum density, the vast majority of the tests were at 90%. Where 95% is shown, data include tests at both 95 and 100% degrees of compaction, with the majority of the tests performed at 95% of maximum density. Table 2 gives a summary of the permeability test data. The first column indicates the general soil group described in Table 1. The second column indicates the degree of compaction of the soil. The higher the percent dry density, the greater the compaction. The four soil types each have been tested at two different compaction rates. The data indicate that additional compaction of the same soil reduces the permeability of the soils by a factor of 2 to 13. The average permeability values are listed in the fourth column. These values, when multiplied by the depth of a lagoon and divided by the thickness of the liner, predict the seepage rate. The last column of Table 2, shows the predicted seepage rate for a lagoon with an average depth of 4 feet and a liner thickness of 1 foot. Kansas Department of Health and Environment (KDHE) regulations require that initial seepage be less than .25 inches per day. These data show that almost all soils in groups II, III, and IV can be adequately sealed. The permeability values shown are median values, so some soils in all the groups may have excessive seepage. Testing of existing soils is recommended to assess local conditions. Soil liners are relatively impervious barriers used to reduce seepage losses to an acceptable level. One method of providing a liner for a waste storage structure is to improve the soils at the excavated grade by disking, watering, and compacting them to a suitable thickness. Soils with suitable properties make excellent material for liners, but the liners must be designed and installed correctly. Soil has an added benefit of providing an attenuation medium for the pollutants. Those on-site soils in Groups I considered to be unsuitable usually can be treated with bentonite to produce a satisfactory soil liner. Additives such as bentonite or soil dispersants should be added and mixed well into a soil prior to compaction. A soil liner may also can be constructed by compacting imported clay from a nearby borrow source onto the bottom and sides of the storage pond. This is often the most economical method of constructing a clay liner, if suitable soils are available nearby. Concrete or synthetic materials such as GCL's (geosynthetic clay liners) and geomembranes also can serve as liners. In all cases, liners should provide a reduction in seepage from the storage/treatment pond and diminish the potential for contamination of groundwater. Soils that have less than 20% passing a No. 200 sieve and have a plasticity index less than 5. Generally, these soils have the highest permeability and, in their natural state, could allow excessive seepage losses. Soils that have 20 to 100% passing a No. 200 sieve and have a plasticity index less than or equal to 15. Also included in this group are soils with less than 20% passing the No. 200 sieve with fines having a plasticity index of 5 or greater. Soils that have 20 to 100% passing a No. 200 sieve and have a plasticity Index of 16 to 30. These soils generally have a very low permeability, good structural features, and only low to moderate shrink-swell behavior. Soils that have 20 to 100% passing a No. 200 sieve and have a plasticity index of more than 30. Normally, these soils have a very low permeability. However, because of their sometimes blocky and fissured structure, they often can experience high seepage losses through cracks that can develop when the material is allowed to dry. They possess good attenuation properties, if the seepage does not move through the cracks. Group I II III IV I I II II III III IV IV 85-90 85-90 85-90 95 95 95 95 85-90 27 16 376 244 226 177 41 54 Permeability Median K cm/sec 7.2 x 10-4 3.5 x 10-4 4.8 x 10-6 1.5 x 10-6 8.8 x 10-7 2.1 x 10-7 4.9 x 10-7 3.5 x 10-8 Seepage (12-inch-thick liner 4 ft. avg. liquid depth) inch/day .85 .24 .15 .036 .084 .006 Cattlemen’s Day 1998 ACKNOWLEDGEMENTS Listed below are individuals, organizations, and firms that have contributed to this year’s beef research program through financial support, product donations, or services. We appreciate their help! ADM Milling Company, Decatur, Illinois American Crystal Sugar Company, Moorhead, Minnesota Balchem Corporation, Slate Hill, New York BASF Animal Nutrition, Mount Olive, New Jersey Bayer Animal Health, Shawnee Mission, Kansas Bert and Wetta-Abilene, Abilene, Kansas Boehringer Ingelheim Animal Health, St. Joseph, Missouri Lee Borck, Larned, Kansas Brill Corporation, Norcross, Georgia Buckhead Beef, Atlanta, Georgia Bunge Corporation, Emporia, Kansas Cargill Flour Milling Division, Wichita, Kansas Cargill Molasses Liquid Products, Minneapolis, Minnesota Central City Scale, Central City, Nebraska Cereal Food Processors, Mission Woods, Kansas CLAAS of America, Columbus, Indiana Consolidated Nutrition, Omaha, Nebraska Elanco Animal Health, Indianapolis, Indiana Excel Corporation, Wichita, Kansas Farmland Industries, Kansas City, Missouri Farnam Companies, Inc., Phoenix, Arizona Ferrell-Ross, Amarillo, Texas Feed Energy Company, Des Moines, Iowa Finnsugar Bioproducts, Inc., Schaumburg, Illinois Fort Dodge Animal Health, Fort Dodge, Iowa Frigoscandia Food Process Systems, Bellevue, Washington Frisbie Construction, Gypsum, Kansas Great Plains Alfalfa, Pratt, Kansas Heartland Cattle Company, McCook, Nebraska Hoechst Roussel Vet, Somerville, New Jersey Hubbard Feeds, Inc., Mankato, Minnesota ibp, inc., Emporia, Kansas Iowa Limestone Company, Des Moines, Iowa Intervet Inc., Millsboro, Deleware Kansas Artificial Breeding Service Unit, Manhattan, Kansas Kansas Beef Council, Topeka, Kansas Kansas Livestock Assn., Topeka, Kansas Kansas Grain Sorghum Commission, Topeka, Kansas Kansas Soybean Commission, Topeka, Kansas Kansas Wheat Commission, Topeka, Kansas Kemin Industries, Inc., Des Moines, Iowa Knight Feedlot, Lyons, Kansas Lallemand, Inc., Rexdale, Ontario, Canada Lignotech USA, Rothschild, Wisconsin Livestock and Meat Industry Council, Inc. (LMIC), Manhattan, Kansas Losey Bros., Agra, Kansas Merial Animal Health, Rahway, New Jersey M&M Livestock Products Co., Eagle Grove, Iowa National Byproducts, Des Moines, Iowa Novus International Inc., St. Charles, Missouri Peterson Farms, Wamego, Kansas Pfizer Animal Health, Exton, Pennsylvania Pharmacia and Upjohn, Kalamazoo, Michigan Pioneer Hi-Bred International, Inc., Johnson, Iowa Research Institute on Livestock Pricing, Blacksburg, Virginia Richard Porter, Porter Farms, Reading, Kansas Roche Animal Health, Nutley, New Jersey Schering-Plough Animal Health, Kenilworth, New Jersey Select Sires, Plain City, Ohio Stafford County Flour Mills, Hudson, Kansas Taylor Implement, Hoxie, Kansas Terra Nitrogen Corporation, Sioux City, Iowa USDA Food Safety Consortium, Washington, DC USDA, Cooperative State Research Education and Extension Service, Washington, DC Vet Life, Inc., Overland Park, Kansas Wall-Rogalsky Flour Milling Company, McPherson, Kansas Western Star Mill Company, Salina, Kansas BIOLOGICAL VARIABILITY AND STATISTICAL EVALUATION OF DATA The variability among individual animals in an experiment leads to problems in interpreting the results. Animals on treatment X may have a higher average daily gain than those on treatment Y, but variability within the groups may indicate that the difference between X and Y is not the result of the treatment alone. You can never be totally sure that the difference you observe is due to the treatment, but statistical analysis lets researchers calculate the probability that such differences are from chance rather than from the treatment. In some articles, you will see the notation “P<.05.” That means the probability that the observed difference was due to chance is less than 5%. If two averages are said to be “significantly different,” the probability is less than 5% that the difference is due to change- the probability exceeds 95% that the difference is true and was caused by the treatment. Some papers report correlations — measures of the relationship between traits. The relationship may be positive (both traits tend to get larger or smaller together) or negative (as one gets larger, the other gets smaller). A perfect correlation is either +l or -1. If there is no relationship at all, the correlation is zero. You may see an average given as 2.5 ± .1. The 2.5 is the average; .l is the “standard error.” That means there is a 68% probability that the “true” mean (based on an unlimited number of animals) will be between 2.4 and 2.6. “Standard deviation” is a measure of variability in a set of data. One standard deviation on each side of the mean is expected to contain 68% of the observations. Many animals per treatment, replicating treatments several times, and using uniform animals all increase the probability of finding real differences when they actually exist. Statistical analysis allows more valid interpretation of the results, regardless of the number of animals in an experiment. In the research reported herein, statistical analyses are included to increase the confidence you can place in the results. In most experiments, the statistical analysis is too complex to present in the space available. Contact the authors if you need further statistical information. WEATHER DATA, 1996-1997 On the following page are graphs of the 1996 and 1997 Manhattan weather. They were produced by the Kansas State University Weather Data Library. The smooth line that starts in the lower left corner of each graph is the normal accumulated precipitation since January 1. The rough line starting in the lower left corner represents actual accumulated precipitation. A long horizontal section of that line represents time during which no precipitation fell. A vertical section represents precipitation. The other two smooth lines represent average daily high and low temperatures, and the rough lines represent actual highs and lows. These graphs are included because much of the data in this publication, especially data on animal maintenance requirements and forage yields, can be influenced by weather. Weather graphs have been included in Cattlemen’s Day publications since 1985. Summaries of Weather in Manhattan, KS, 1996 and 1997 SRP March


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Kansas Agricultural Experiment Station. 1998 Cattlemen's Day, Kansas Agricultural Experiment Station Research Reports, 1998,