Life Sciences Commons^™

Value And Use Of Artificial Insemination By Beef Producers, S. K. Johnson, Garland R. Dahlke

Kansas Agricultural Experiment Station Research Reports

Artificial insemination and estrous synchronization remain underutilized by U.S. beef producers. The most recent National Animal Health Monitoring Survey (NAHMS 2007–08) reported that 7.6% of producers used artificial insemination and 7.9% used estrous synchronization. The most common reason cited for not using these reproductive technologies was time and labor, followed by cost and difficulty. Little information is available on actual management practices used by producers who do use these technologies and their value to such operations.

Swine Day 2015 Supplements, R. D. Goodband, M. D. Tokach, S. S. Dritz, J. M. Derouchey, J. C. Woodworth

Kansas Agricultural Experiment Station Research Reports

It is with great pleasure that we present the 2015 Swine Industry Day Report of Progress. This report contains updates and summaries of applied and basic research conducted at Kansas State University during the past year. We hope that the information will be of benefit as we attempt to meet the needs of the Kansas swine industry.

Guanidinoacetic Acid As A Precursor Of Creatine For Cattle, M. Ardalan, E. Batista, C. Armendariz, E. Titgemeyer

Kansas Agricultural Experiment Station Research Reports

Creatine serves as an energy-storing molecule in muscle, and in mammals it can be synthesized in the liver from guanidinoacetic acid (GAA). With this study, we evaluated whether GAA supplementation would lead to creatine production in cattle similarly to other species. Because the synthesis of creatine from GAA requires the use of a methyl group, we also evaluated the effect of supplementing methionine, as a methyl group donor, on the synthesis of creatine.
Supplemental GAA did increase plasma concentrations of creatine. Also, blood concentrations of arginine, a precursor to GAA, were increased by GAA supplementation, suggesting that arginine use for …

Evaluation Of Calcium Hydroxide-Treated Stover (Second Crop) In Receiving And Growing Diets And Effects On Cattle Performance, T. Spore, S. Montgomery, C. Vahl, B. E. Oleen, W. R. Hollenbeck, J. W. Waggoner, J. Hill, D. A. Blasi

Kansas Agricultural Experiment Station Research Reports

Production of ethanol from corn as an alternative fuel source has significantly affected the pricing landscape for corn as an energy source for livestock. As ethanol usage has become more prevalent, corn prices have become more volatile, especially in critical corn-growing areas that have been affected by drought. Consequently, many beef cattle feeders have become interested in alternative energy sources in an effort to control cost of gain. Second Crop (ADM Corp., Decatur, IL) is a process in which calcium hydroxide is added to fibrous crop residues, such as wheat straw and corn stover. When applied to low-quality roughages, calcium …

Evaluating The Effect Of Manufacturing Porcine Epidemic Diarrhea Virus (Pedv)-Contaminated Feed On Subsequent Feed Mill Environmental Surface Contamination, L. L. Schumacher, R. A. Cochrane, C. E. Evans, J. R. Kalivoda, J. C. Woodworth, C. R. Stark, C. K. Jones, Rodger G. Main, Jianqiang Zhang, S. S. Dritz, Phillip Charles Gauger

Kansas Agricultural Experiment Station Research Reports

This study aimed to utilize the only known pilot feed mill facility approved for pathogenic feed agent use in the United States to evaluate the effect of manufacturing Porcine Epidemic Diarrhea Virus (PEDV)-contaminated feed on subsequent feed mill environmental surface contamination. In this study, PEDV inoculated feed was manufactured and conveyed on equipment along with four subsequent batches of PEDV-free feed. Equipment and environmental surfaces were sampled using swabs and analyzed for the presence of PEDV RNA by PCR. The experiment was replicated three times with decontamination of the feed mill and all equipment between replications. Overall, environmental swabs indicated …

Application Of Alternative Floor Space Prediction Equations Using Microsoft Excel®, J. R. Flohr, M. D. Tokach, S. S. Dritz, J. C. Woodworth, J. M. Derouchey, R. D. Goodband

Kansas Agricultural Experiment Station Research Reports

The following information is related to the use of a spreadsheet tool designed to estimate the growth rate of finishing pigs provided varying floor space allowances. The spreadsheet is broken into four sections: 1) the adjustment observation section, 2) the estimate input section, 3) the database range information, and 4) the predicted performance output. Sections 1 and 2 allow users to input information to adjust the prediction equations to specific herd growth rates as well as information needed to calculate the growth rate estimates for different floor space allowances. This tool allows producers to utilize the prediction equations without having …

Genetic Variance And Covariance Components For Feed Intake, Average Daily Gain, And Postweaning Gain In Growing Beef Cattle, K. J. Retallick, J. M. Bormann, R. L. Weaber, M. D. Macneil, H. L. Bradford, Harvey C. Freetly, W. M. Snelling, Mark Thallman, D. Moser, Larry Kuehn

Kansas Agricultural Experiment Station Research Reports

Feed is the greatest cost for a beef cattle production enterprise. Data collection to determine feed efficiency of animals is also costly, because both gain and intake records are needed to calculate feed efficiency. Electronic intake monitoring systems such as GrowSafe or Insentec to collect feed intake data are expensive and thus limit the number of animals that can be tested. Scientists have worked to pinpoint optimal test durations for collecting both weight gain and feed intake records to lessen costs.

A 70-day performance test is currently recommended for accurate calculation of efficiency, with growth data as the limiting factor. …

Comparing Standing Heat And Estrotect Heat Detection Patches, S. K. Johnson, J. R. Jaeger

Kansas Agricultural Experiment Station Research Reports

A recent survey showed that 66% of producers surveyed used some amount of heat detection in their artificial insemination program, and 74% of producers that used heat detection aids had tried Estrotect (Rockway, Inc.; Spring Valley, WS) heat detection patches. The peel-and-stick application made Estrotect more popular than types that required adhesive application. The patches are designed so that when the animal is mounted the top surface layer is removed, much like scratching a lottery ticket. After several mounts the entire layer is removed, leaving a bright-colored surface behind. A new type of patch, Standing Heat (Standing Heat, LLC; Dannebrog, …

Effects Of Cobalt Source On Rate And Extent Of Dry Matter And Fiber Degradation In Vitro, F. Vargas-Rodriguez, Gail Carpenter, J. Defrain, B. Bradford

Kansas Agricultural Experiment Station Research Reports

Positive effects on fiber degradation have been observed when supplemental cobalt was fed to ruminants. This study tested the effects of cobalt carbonate (CoCarb) and cobalt glucoheptonate (CoGH) at different concentrations on in vitro fermentation rate, fermentation end-product concentrations, and degradation of feed dry matter and neutral detergent fiber. Compared to CoCarb, CoGH increased dry matter disappearance and neutral detergent fiber degradation when added at 1 part per million (ppm) cobalt or less. Furthermore, CoGH had limited effects on the biohydrogenation of long chain fatty acids, whereas CoCarb appeared to stimulate this process when added at more than 3 ppm …

Effects Of Dietary Fat Source On Performance Of Lactating Dairy Cows Fed A Pre-Mixed Concentrate, C. Ylioja, C. Abney-Schulte, Rick A. Stock, B. Bradford

Kansas Agricultural Experiment Station Research Reports

Inclusion of a pre-blended concentrate (OneTrak®, Cargill Inc., Blair, NE) in the total mixed ration (TMR) for dairy cows can simplify the daily mixing of dietary ingredients. A cow’s response to fat supplementation can be affected by other dietary ingredients; however, little is known about production responses to dietary fat in diets with high concentrations of non-forage fiber. This study evaluated cow performance in response to fat sources when the ration contained a pre-blended concentrate composed largely of a non-forage fiber source. Six pens of mid-lactation cows were studied; the addition of saturated fat (Energy Booster 100) and rumen-protected unsaturated …

Stability Of Four Commercial Phytase Products Under Increasing Conditioning Temperature, J. A. De Jong, J. C. Woodworth, J. M. Derouchey, M. D. Tokach, R. D. Goodband, S. S. Dritz, C. K. Jones, C. R. Stark

Kansas Agricultural Experiment Station Research Reports

A study was conducted to determine the stability of four commercial phytase products exposed to increasing conditioning temperatures. The four commercial products used were: Quantum Blue G (AB Vista, Plantation, FL); Ronozyme Hi Phos GT (DSM Nutritional Products, Parsippany, NJ); Axtra Phy TPT (Dupont, Wilmington, DE); and Microtech 5000 Plus (Guangdong Vtr Bio-Tech Co., Ltd., Guangdong, China). The phytase products were mixed as part of corn-soybean meal-based swine diet at a concentration recommended to provide a 0.12% aP release. All four diets were analyzed for phytase activity to establish baseline phytase activity for each product. Diets were then conditioned at …

Evaluating The Impact Of Maternal Vitamin D Supplementation On Sow Performance, Serum Vitamin Metabolites, Neonatal Muscle And Bone Characteristics, And Subsequent Pre-Weaning Pig Performance, J. R. Flohr, J. C. Woodworth, M. D. Tokach, S. S. Dritz, R. D. Goodband, J. M. Derouchey, J. R. Bergstrom

Kansas Agricultural Experiment Station Research Reports

A total of 56 gestating sows (PIC 1050; 35-d post-insemination) were used in a 30-d trial to determine the serum 25(OH)D₃response to increasing concentrations of vitamins D3. At initiation, sows were randomly allotted to 1 of 7 dietary vitamin D₃treatments (91, 363, 726, 1,451, 2,903, 5,806, or 11,612 IU of vitamin D₃/lb of complete diet) with 8 sows per treatment. All sows were fed 5.5 lb daily at 0800. Increasing vitamin D3 increased (quadratic; P<0.001) serum 25(OH)D₃with the response depicted by the following prediction equation:

Serum 25(OH)D3_,ng/mL = 35.1746 + (0.002353 × …

Effects Of Various Forage Systems On Grazing And Subsequent Finishing Performance, L. W. Lomas, J. L. Moyer

Kansas Agricultural Experiment Station Research Reports

A total of 200 mixed black yearling steers were used to compare grazing and subsequent finishing performance from pastures with ‘MaxQ’ tall fescue, a wheat-bermudagrass double-crop system, or a wheat-crabgrass double-crop system in 2010, 2011, 2012, 2013, and 2014. Daily gains of steers that grazed ‘MaxQ’ tall fescue, wheat-bermudagrass, or wheat-crabgrass were similar (P>0.05) in 2010, daily gains of steers that grazed wheat-bermudagrass or wheat-crabgrass were greater (P>0.05) than those that grazed ‘MaxQ’ tall fescue in 2011 and 2012, daily gains of steers that grazed wheat-crabgrass were greater (P>0.05) than those that grazed wheat-bermudagrass …

Determining The Minimum Infectious Dose Of Porcine Epidemic Diarrhea Virus (Pedv) In A Feed Matrix, L. L. Schumacher, J. C. Woodworth, C. R. Stark, C. K. Jones, R. A. Hesse, Rodger G. Main, Jianqiang Zhang, Phillip Charles Gauger, S. S. Dritz, M. D. Tokach

Kansas Agricultural Experiment Station Research Reports

Understanding the magnitude of transmissible risk Porcine Epidemic Diarrhea Virus (PEDV)-infected feed imposes and establishing the minimum infectious dose of PEDV in a feed matrix are important components in strengthening virus prevention and control methods. In this study, an experiment was performed involving 30 crossbred, 10-d-old pigs that were used as a bioassay model for the minimum infectious dose of PEDV in feed. The PEDV was first diluted using tissue culture media to form 8 serial 10-fold dilutions. An aliquot of the original stock virus at 5.6 x 10⁵tissue culture infectious dose/ml (TCID₅₀/ml), each serial PEDV …

Effects Of Supplementation With Corn Or Dried Distillers Grains On Gains Of Heifer Calves Grazing Smooth Bromegrass Pastures, L. W. Lomas, J. L. Moyer

Kansas Agricultural Experiment Station Research Reports

Thirty heifer calves grazing smooth bromegrass pastures were used to compare supplementation with 0.5% of body weight per head daily of corn or dried distillers grains (DDG). Daily gains of heifers supplemented with corn or DDG were similar (P>0.05).

Genetic Improvement Made Through Dna Testing And Artificial Insemination To High- Growth, High Carcass Value Angus Sires, L C. Grimes, L. R. Corah, T. Brink, M. R. Gardiner, A. K. Sexten

Kansas Agricultural Experiment Station Research Reports

The beef industry has improved the recording of pedigrees and performance data through the use of breed associations and herd health databases. Constant evaluation of genetics and performance has allowed producers to make more informed breeding decisions that help improve herd productivity. As a result of recent droughts and elevated feed and grain prices, however, the American beef cowherd is at a record-low 29 million head. For the United States to continue to be the leading producer of beef in the world, the industry must adopt technologies that improve efficiency of the cowherd and the quality of beef being produced. …

Nursing Reduction Strategies To Enhance Estrus In Lactating Sows And Effects On Performance Of Pigs To Market Weight, H. L. Frobose, M. D. Tokach, J. M. Derouchey, S. S. Dritz, R. D. Goodband, J. C. Woodworth, J. L. Nelssen, D. L. Davis

Kansas Agricultural Experiment Station Research Reports

A total of 135 sows (PIC 1050), ranging from parity 1 to 5 (2.6 ± 1.4), were used in 5 consecutive farrowing groups (February to August). The objectives were to evaluate different suckling reduction strategies for inducing lactational estrus and the effects on sow fertility and piglet growth. Litter size was equalized within parity (11.5 ± 1.1 piglets) at d 2 after farrowing. At d 18, sows were assigned to 1 of 5 treatments (n = 26 to 28) based on parity, farrowing date, and suckled litter size. Treatments were: 1) control; 2) sows that were paired within parity and …

Effects Of Potential Detoxifying Agents On Growth Performance And Deoxynivalenol (Don) Urinary Balance Characteristics Of Nursery Pigs Fed Don-Contaminated Wheat, H. L. Frobose, E. W. Stephenson, M. D. Tokach, J. M. Derouchey, S. S. Dritz, R. D. Goodband, J. C. Woodworth, R. E. Musser

Kansas Agricultural Experiment Station Research Reports

Two experiments were conducted to evaluate the effects of detoxifying agents on the growth performance of nursery pigs fed diets contaminated with deoxynivalenol (DON). Naturally DON-contaminated wheat (6 ppm) replaced noncontaminated wheat in diets to achieve desired dietary DON concentrations. Basal ingredients were tested for mycotoxin and amino acid content prior to diet manufacturing. Diets were pelleted at 180˚F with a 45-s conditioning time.

A total of 238 barrows and gilts (PIC 327 × 1050; initially 29.6 ± 5.6 lb and 42 d of age) were used in a 21-d growth study. Pens of pigs were allotted by BW to …

Evaluating The Effects Of Maternal Vitamin D Supplementation On The Subsequent Growth Performance And Carcass Characteristics Of A Subsample Population Of Growing Pigs, J. R. Flohr, J. C. Woodworth, M. D. Tokach, S. S. Dritz, R. D. Goodband, J. M. Derouchey, J. R. Bergstrom

Kansas Agricultural Experiment Station Research Reports

A subsample of 448 growing pigs (PIC 327 × 1050), or approximately 50% of pigs weaned from sows fed varying dietary vitamin D regimens, were used in a split-plot design to determine the influence of maternal and nursery vitamin D regimens on growth performance. Sows were previously administered diets containing vitamin D as either: 1) low vitamin D₃(363 IU/lb); 2) medium vitamin D₃(907 IU/lb); 3) high vitamin D₃(4,354 IU/lb); or 4) 23μg 25(OH)D₃/lb (Hy-D, DSM Nutritional Products Inc, Parsippany, NJ) as described by Flohr et al. (20153) throughout gestation and …

Effects Of Amino Acid And Energy Intake During Late Gestation On Piglet Birth Weight And Reproductive Performance Of Gilts And Sows Housed Under Commercial Conditions, M. A. Goncalves, K. M. Gourley, S. S. Dritz, M. D. Tokach, N. M. Bello, J. M. Derouchey, J. C. Woodworth, R. D. Goodband

Kansas Agricultural Experiment Station Research Reports

The objective of this study was to determine the effects of amino acid (AA) and energy intake during late gestation on piglet birth weight and reproductive performance of high-performing gilts and sows housed under commercial conditions. At d 90 of gestation, a total of 1,102 females (PIC 1050) were housed in pens by parity group (P1 or P2+), blocked by weight within each pen, and each female was randomly assigned to dietary treatments within weight block. Dietary treatments consisted of combinations of 2 standardized ileal digestible (SID) AA (10.7 or 20.0 g SID Lys intake/d with other AA meeting or …

Effects Of Grinding Corn Through A 2-, 3-, Or 4-High Roller Mill On Milling Characteristics, And Commercial Finishing Pig Growth Performance And Carcass Characteristics, J. T. Gebhardt, K. F. Coble, M. D. Tokach, J. M. Derouchey, R. D. Goodband, J. C. Woodworth, C. R. Stark, C. K. Jones, S. S. Dritz

Kansas Agricultural Experiment Station Research Reports

A total of 922 pigs [PIC TR4 × (FAST Large white × PIC Landrace), initially 88.3 lb] were used in a 97-d experiment to determine the effects of grinding corn through various roller mill configurations on milling characteristics as well as growth performance and carcass characteristics of finishing pigs in a commercial setting. Pens were randomly allotted to 1 of 4 experimental treatments by initial BW with 11 pens per treatment and 21 pigs per pen. All diets were fed in 5 phases with the same corn-soybean meal-based diets containing 20% dried distiller’s grains with solubles. Experimental treatments included: (1) …

Effect Of Fish Meal Source On Nursery Pig Performance, A. M. Jones, J. C. Woodworth, R. D. Goodband, M. D. Tokach, S. S. Dritz, J. M. Derouchey

Kansas Agricultural Experiment Station Research Reports

A total of 600 pigs (Exp. 1, n=250, PIC 327 × 1050; Exp. 2, n=350, DNA Line 200 × 400 with an initial BW of 15.6 ± 0.1 and 14.3 ± 0.2, respectively) were used in two 14-d experiments to determine the effects of fish meal source on nursery pig performance. Each experiment had 10 pens per treatment and five pigs per pen. In Exp. 1, pigs were allotted to pens at weaning (d 0) and were fed a common starter diet for 5 d. On d 5, pens of pigs were allotted by BW to experimental diets that were …

Evaluating The Efficacy Of A Novel Phytase Source, J. R. Flohr, J. M. Derouchey, M. D. Tokach, S. S. Dritz, J. C. Woodworth, R. D. Goodband

Kansas Agricultural Experiment Station Research Reports

A total of 350 nursery pigs (PIC 1050 barrows, initially 33.2 lb and 49 d of age) were used in a 21-d study to determine the aP release curve for a novel phytase product (Microtech 5,000, VTR Bio-tech Co., Guangdong, China). Pigs were randomly allotted to pens at arrival to the facility, and on d 0 of the trial pens were allotted to 1 of 7 treatments in a randomized complete block design. There were 5 pigs per pen and 10 pens per treatment. Pigs were fed corn-soybean meal-based diets formulated to 1.25% SID lysine. A single batch of the …

Effects Of Standardized Ileal Digestible Valine:Lysine Ratio On The Growth Performance And Economics Of Finishing Pigs From 55 To 100 Lb, M. A. Goncalves, J. Jacquez, M. D. Tokach, S. S. Dritz, K. J. Touchette, J. M. Derouchey, J. C. Woodworth, R. D. Goodband

Kansas Agricultural Experiment Station Research Reports

The objective of these experiments was to determine the effects of SID Val:Lys ratio in low CP and low lysine diets on the growth performance and economics of finishing pigs from 55 to 100 lb. In Exp. 1, a total of 1,134 gilts (PIC 337 × 1050, initially 68.8 lb BW) were used in a 19-d growth trial with 27 pigs per pen and seven pens per treatment in a randomized complete block design with pens blocked by initial average BW. There was a total of six dietary treatments: 59.0, 62.5, 65.9, 69.6, 73.0, and 75.5% SID Val:Lys ratio. In …

The Effects Of Increasing Stocking Density On Finishing Pig Growth Performance And Carcass Characteristics, L. L. Thomas, R. D. Goodband, M. D. Tokach, J. M. Derouchey, J. C. Woodworth, S. S. Dritz

Kansas Agricultural Experiment Station Research Reports

A total of 405 pigs (PIC 327 × 1050) from 2 consecutive finishing groups (group 1 initially 145 ± 3.9 lb, group 2 initially 134 ± 5.5 lb) were used to examine the effects of stocking density on finishing pig growth performance and carcass characteristics. Pigs were randomly allotted to pens upon entry into the finishing facility. Pens of pigs were balanced by initial BW and randomly allotted to 1 of 3 treatments with either 7 or 8 replications per treatment (group 1 and 2, respectively). Pens were stocked with 9 pigs, and adjustable gates provided treatments that allowed for …

Effects Of Varying Methodologies On Grain Particle Size Analysis, J. R. Kalivoda, C. K. Jones, C. R. Stark

Kansas Agricultural Experiment Station Research Reports

Particle size reduction is an important component of feed manufacturing that impacts pellet quality, feed flowability, and pig feed efficiency. The correct determination of particle size is important for feed manufacturers, nutritionists, and pork producers to meet target specifications. The current method for determining the geometric mean diameter (dgw) and geometric standard deviation (Sgw) of grains has been published by the ANSI/ASAE S319.4. This method controls many variables, including the suggested quantity of initial material and the type, number, and size of sieves. However, the method allows for variation in shake time, sieve agitators, and the use of a flow …

Finely Grinding Cereal Grains In Pelleted Diets Offers Little Improvement In Nursery Pig Growth Performance, G. E. Bokelman, J. A. De Jong, J. R. Kalivoda, A. Yoder, C. R. Stark, J. C. Woodworth, C. K. Jones

Kansas Agricultural Experiment Station Research Reports

Five experiments were conducted to determine the effects of corn particle size and diet form on nursery pig performance and feed preference. In Exp. 1, 192 nursery pigs (PIC 327 × 1050; initially 14.7 lb and 26 d of age) were used in a 35-d experiment. Pens of pigs were balanced by BW and allotted to 1 of 4 treatments with 6 pigs per pen and 8 pens per treatment. The same corn and soybean meal-based diet formulation was used for all treatments. The 2 × 2 factorial consisted of the main effects of corn particle size (400 vs. 700 …

Lactipro (Megasphaera Elsdenii) Increases Ruminal Ph And Alters Volatile Fatty Acids And Lactate During Transition To An 80% Concentrate Diet, J. Thieszen, C. L. Van Bibber, J. E. Axman, J. S. Drouillard

Kansas Agricultural Experiment Station Research Reports

Direct-fed microbials commonly have been used to enhance performance or to decrease shedding of foodborne pathogens in beef cattle.Megasphaera elsdeniiis a recently introduced probiotic bacteria marketed under the trade name Lactipro (MS-Biotec Inc., Wamego, KS) and is a key lactate-fermenting bacterium in the rumens of cattle fed high-concentrate diets.Megasphaera elsdeniiis responsible for metabolizing up to 95% lactic acid within the rumen, and thus is an important species for controlling occurrence of ruminal acidosis. The objective of this study was to evaluate changes in ruminal pH and volatile fatty acid concentration during the transition from a diet …

Evaluation Of Extreme Thermal Processing Methods To Improve Nutrient Utilization Of Low-Energy Diets For Finishing Pigs, G. E. Bokelman, K. F. Coble, C. R. Stark, J. C. Woodworth, M. D. Tokach, C. K. Jones

Kansas Agricultural Experiment Station Research Reports

A total of 270 pigs (PIC 337 × 1050; initially 115.7 lb) were used in a 79-d experiment to determine the effects of long-term conditioning or extrusion on finishing pig nutrient digestibility, growth performance, and carcass characteristics. There were 7 or 8 pigs per pen and 9 pens per treatment. Treatments included the same basal diet processed as: 1) nonprocessed mash; 2) pelleted with 45-s conditioner retention time; 3) pelleted with 90-s conditioner retention time; or 4) extruded. Diets were fed in three phases with the same low-energy diet formulation fed across treatments, containing 30% corn dried distillers grains with …

Hops Βeta-Acid Extract Yields Feedlot Performance Similar To Rumensin, J. E. Axman, C. L. Van Bibber, C. Alvarado, J. Thieszen, J. S. Drouillard

Kansas Agricultural Experiment Station Research Reports

Hops (Humulus lupulus) have played an integral role in beer manufacturing and are widely known for their antimicrobial and preservative properties. α-acids of hops are extracted and utilized to enhance beer flavor, leaving residues largely composed of β-acids. Beta-acid extracts of hops are structurally similar to ionophores and may express ionophore-like traits. Ionophores, including Rumensin (Elanco Animal Health, Greenfield, IN), are used to improve feed efficiency and to decrease the incidence of digestive disturbances in feedlot cattle. A large portion ofin vitrostudies show benefits from feeding hops or hop acids with results similar to ionophores; however, …