Kansas State University Research Articles

Performance of Kansas State University’s Cold and Large Patch-Tolerant Zoysiagrasses in the National Turfgrass Evaluation Program Test

The National Turfgrass Evaluation Program (NTEP) Zoysia Test was planted in 2019 at the Kansas State University Olathe Horticulture Center, Olathe, KS. Since planting, three experimental genotypes developed at K-State (with cooperators noted below) have outperformed ‘Meyer’ in establishment rate, turf quality, drought tolerance, and fall color. Earlier research has demonstrated large patch tolerance in all three experimental genotypes.

Registration of ‘KS Silverado’ hard white winter wheat

Abstract‘KS Silverado’ (Reg. no. CV‐1175, PI 693936) hard white winter wheat (Triticum aestivum L.) was developed at the Agricultural Research Center–Hays, Kansas State University, and released by the Kansas Agricultural Experiment Station in 2019. KS Silverado was selected from a three‐way cross KS05HW122‐5‐2//KS05HW15‐2‐2/KS06HW46‐3 made in 2008 at Hays, KS. The objective of this cross was to develop a hard white winter wheat cultivar that is adapted to Kansas. KS Silverado was selected as an F6–derived line using a modified bulk method and tested in yield trials across Kansas for five years. KS Silverado is medium‐early and medium‐short and has good straw strength, above average grain volume weight, and very competitive grain yield in western and central Kansas. KS Silverado is tolerant to preharvest sprouting and has a good resistance package to diseases and insects, including Wheat streak mosaic virus, leaf rust, Soilborne wheat mosaic virus, and Hessian fly. It also has good milling and bread‐making qualities.

Leading In the Skin You're In: A Conversation with Dr. Tawana Grover and Dr. Steve Joel

Leading In the Skin You're InA Conversation with Dr. Tawana Grover and Dr. Steve Joel Ryan Teten The 2020 Warner Lecture, October 7, 2020 Dr. Ryan Teten: I would like to welcome everybody. On behalf of the College of Arts and Sciences and the University of Nebraska Kearney and College Park here in Grand Island, my name is Dr. Ryan Teten and I am the Dean of the College of Arts and Sciences at the University of Nebraska Kearney. I'd like to first take the time to thank both of our presenters, the amazing staff here at College Park including LJ McCormick (the executive director), Dr. Peter Longo, Steve Hansen, Kristy Milks, and everyone else who lent their assistance to this event to make it possible. Last week, the University of Nebraska at Kearney and College Park, Grand Island, collaborated to deliver undergraduate and graduate classes alike in the face-to-face format from College Park here in Grand Island. It's an incredible opportunity, and we're proud to have LJ and his entire staff as part of the new Loper family. The Warner Lecture is a signature event supported by the Office of the Chancellor and named for late state senators Senator Charles Warner and his son Jerome Warner. Charles Warner is often referred to as the "grand old man" of Nebraska politics. He was a member of the Nebraska House and the Nebraska Senate and then the Nebraska Unicameral and served as the combined legislature's first Speaker. He was later elected Lieutenant Governor four times serving from 1949 until his death at age 80. While serving in the Nebraska House of Representatives in 1903, he led the effort to establish the Kearney Normal School. Jerome Warner continued this drive for public service and public education and served 35 years in elected service as a state senator including as Speaker and headed committees on education, appropriations, revenue, and the executive board. His leadership helped make Kearney State College part of the State University System in 1989. We are pleased this evening to honor these individuals with the annual Warner Lecture and we are equally honored to host Dr. Tawana Grover and Dr. Steve Joel as presenters for this special event. Dr. Tawana Grover serves as Superintendent of Grand Island Public Schools in Grand Island, Nebraska; she serves a district of over 10,000 students. Prior to becoming Superintendent in 2016, she served as Chief Human Resource Officer, Executive Director of Federal Programs, Director of Special Programs, Principal, and Assistant Principal in Texas. Dr. Grover possesses a sharp grasp of competencies for highly effective instructional leadership, and she earned a PhD from the University of North Texas and her education degrees from Doane University and Auburn University in Montgomery, Alabama. Dr. Steve Joel became Superintendent of Lincoln Public Schools in 2010. Previously, he served 10 years as a Superintendent in Grand Island, Nebraska, and eight years in Beatrice, Nebraska. A native of Long Island, New York, he has degrees from Doane College, the University of Nebraska Lincoln, and Kansas State University. Dr. Joel's leadership is focused on comprehensive solutions to significant school and community issues. Lincoln Public Schools is growing rapidly to include over 42,000 students and 8,000 staff members. We would like to welcome both of these presenters, and they will open with a statement on the theme of today's Warner Lecture: "Leading In the Skin You're In." Dr. Joel, would you like to go first? [End Page 125] Dr. Steve Joel: Yes. Well, thank you very much for the invitation. It's wonderful to be back in Grand Island. We spent 10 years here and we have tremendous memories. I'm also very, very proud of my colleague, Dr. Tawana Grover, who has just done an amazing job leading Grand Island Public Schools. She is a leader within the Grand Island community, so it is a real pleasure to share this presentation with her. One of the things that I was thinking about as we were coming here was that I have had a chance to really enjoy a lot of great opportunities. You know, I'm very...

Control of Volunteer Enlist Corn in Enlist E3 Soybean

Recent development of Enlist corn allows the use of 2,4-D choline (Enlist One), glyphosate (Roundup PowerMax), glufosinate (Liberty), and aryloxyphenoxypropionate (FOPs) herbicides for controlling grass and broadleaf weeds. However, volunteer Enlist corn plants can cause infestation in subsequent Enlist E3 soybean (resistant to 2,4-D, glyphosate, and glufosinate) in areas where a corn-soybean rotation is commonly practiced. The main objective of this research was to determine the effectiveness of cyclohexanedione (DIMs) herbicides alone or in tank-mixtures with Enlist One for Enlist corn control in Enlist E3 soybean. A field study was conducted in the 2020 growing season at the Kansas State University Agricultural Research Center (KSUARC) near Hays, KS. Enlist corn hybrid DKC62-53 was planted at 17,420 seeds/a on May 13, 2020. Enlist E3 soybean variety P30T92E was planted at 152,000 seeds/a in a perpendicular direction to corn on May 20, 2020. Herbicide treatments, including clethodim (Select Max) and sethoxydim (Poast Plus) were tested alone or in tank-mixtures with Enlist One as early POST (EPOST, 8- to 12-inch tall corn), or late postemergence (POST) (12- to 30-inch tall corn). Results indicated that Select Max applied EPOST alone provided an excellent, season-long control (95 to 99%) and highest biomass reduction (up to 100%) of volunteer Enlist corn in Enlist E3 soybean. However, volunteer corn control was significantly reduced when Enlist One was tankmixed with Poast Plus. Volunteer corn control was low to moderate (50–85%) with all late postemergence (LPOST) programs tested. Soybean grain yield did not differ among EPOST treatments (39 to 44 bu/a), while grain yield was significantly lower (~ 34 bu/a) for LPOST treatments. These results suggested that the EPOST application of Select Max and Poast Plus can effectively control volunteer Enlist corn infestation in Enlist E3soybean. However, adding Enlist One could compromise the efficacy of Poast Plus herbicide.

Auxinic Herbicide Mixtures for Controlling Multiple Herbicide-Resistant Kochia in Fallow

Kochia resistant to glyphosate (Roundup), chlorsulfuron (Glean), and dicamba (Banvel or Clarity) has become quite common in the U.S. Great Plains, whereas multiple resistance to additional herbicides, including fluroxypyr (Starane Ultra), atrazine (AAtrex), and metribuzin (Sencor) has also been reported recently. Effective management of these multiple herbicide-resistant (MHR) kochia populations warrants the need of alternative herbicide strategies. The main objective of this research was to investigate the efficacy of auxinic herbicides, including Duplosan (dichlorprop-p), Weedone (2,4-D), Clash (dicamba), and/or Pixxaro (premix of halauxifen and fluroxypyr) alone or in various combinations for controlling MHR kochia. Separate greenhouse and field experiments were conducted at the Kansas State University Agricultural Research Center (KSU-ARC) in Hays, KS. Greenhouse studies included an MHR kochia population (resistant to glyphosate, dicamba, fluroxypyr, chlorsulfuron, atrazine, and metribuzin) from Garden City, KS, and a susceptible (SUS) kochia population from Hays, KS. The postemergence (POST) applied herbicide programs, including Clash Weedone, Duplosan alone or in tank-mix combinations were tested. Field experiments were conducted in a fallow field at KSU-ARC with a natural infestation of kochia population with multiple resistance to glyphosate and dicamba. Herbicides, including Duplosan, Weedone, Clash, and Pixxaro were tested alone or in tank-mix combinations. Results from greenhouse study indicated that Clash, Duplosan, and Weedone applied alone provided inadequate control (5 to 42%) of MHR kochia at 21 days after treatment (DAT). In contrast, control of SUS population was 83 to 92% with Clash and Duplosan alone treatments. Tank-mixing Duplosan with Clash and/or Clash + Weedone significantly improved visible control (72 to 90%) of MHR kochia as compared to Duplosan, Clash, or Weedone alone treatments. Similarly, tank-mixing Clash to Duplosan or Pixxaro (two-way mixtures) and to Duplosan + Weedone, Pixxaro + Duplosan or Pixxaro + Weedone (three-way mixtures), provided an excellent control (91 to 97%) of MHR kochia compared to Clash, Pixxaro, Weedone, and Duplosan alone treatments in a field study. Altogether, these results suggest that tankmixing Clash with Duplosan and/or Pixxaro can potentially provide synergistic effect in controlling MHR kochia in fallow fields.

Kansas Fertilizer Research 2021

A summary of research conducted in 2018-2020 on fertilizer use and management practices for crops in Kansas. Published in 2021 from the Kansas State University Agricultural Experiment Station and Cooperative Extension Service https://www.ag.k-state.edu/

Effect of Tank-Mixing Glyphosate, Dicamba, and Graminicides on Grass Weed Control in Roundup Ready 2 Xtend Soybeans

The adoption of Roundup Ready 2 Xtendsoybean allows growers to use dicamba (Xtendimax or Engenia) in mixtures with glyphosate (Roundup PowerMax) or graminicides (Select Max or Assure II) for broad spectrum weed control. However, anecdotal evidence suggests that Xtendimax may cause antagonism when applied with Select Max and/or Assure II herbicides. The main objective of this study was to determine the effectiveness of Roundup PowerMax, Select Max, and/or Assure II alone or in tank-mixtures with Xtendimax for grass weed control in Xtendsoybean. Field studies were conducted in 2020 at the Kansas State University Agricultural Research Center (KSU-ARC) near Hays, KS, and at the University of Nebraska, Lincoln, NE (UNL). The dominant grass species at the KSU-ARC site were southwest cupgrass and green foxtail. The dominant grass weed species at the UNL site were giant foxtail, hairy cupgrass, and fall panicum. Treatments, including Select Max, Assure II, and Roundup PowerMax applied as early post-emergence (EPOST; V3-V4 soybean growth stage) alone, or in combination with Xtendimax were tested (see Table 1 for details). Results from the KSU-ARC site indicated that Roundup PowerMax applied alone and in sequential treatments at 5 days prior to or after the application of Xtendimax provided ≥ 85% control of both grass species, whereas the rest of the treatments provided ≤ 71% control. The highest soybean grain yield (13 to 17 bu/a) was observed with Roundup PowerMax alone or in tank-mixtures with Select Max, Assure II and/or Xtendimax. In contrast, tank-mixing Xtendimax to Select Max or Assure II, or Xtendimax applied 5 days prior to the application of Select Max or Assure II, reduced giant foxtail (64 to 82%), and hairy cupgrass (71 to 82%) control at the UNL site. The addition of Roundup PowerMax to tank-mixtures of Xtendimax with Select Max or Assure II restored the efficacy of both Select Max and Assure II on all three grass species. Soybean grain yield (64 to 77 bu/a) did not differ for the majority of treatments at UNL site. These results suggest that addition of Xtendimax with Select Max or Assure II can potentially compromise the efficacy of graminicides, and Roundup PowerMax should be added in these mixtures to optimize grass control in Roundup Ready 2 Xtendsoybean.

Efficacy of Imiflex, Zest, and Assure II on Green Foxtail Control

Grass weeds pose a serious management challenge in grain sorghum. Recent development of three herbicide-tolerant grain sorghum technologies such as Inzen, Igrowth, and DoubleTeam will provide the opportunity for producers to use nicosulfuron (Zest), imazamox (Imiflex), and quizalofop-p-ethyl (FirstAct) for grass weed control, respectively. The main objectives of this research were to (1) determine the effectiveness of Imiflex applied preemergence (PRE) on green foxtail control in comparison to commonly used group 15 herbicides; (2) compare the efficacy of Zest, Imiflex, and Assure II applied early- or late-POST at two different rates; and (3) determine the tank-mix compatibility of Zest, Imiflex, Assure II, and Select Max (clethodim) with 2,4-D (Weedar 64) and dicamba (Clarity) on green foxtail control. Field experiments were conducted in fallow ground with a natural infestation of green foxtail at Kansas State University Agricultural Research Center in Hays, KS. PRE herbicide programs, including Imiflex, Dual II Magnum, Warrant, and Outlook were tested. Imiflex, Zest, and Assure II were tested in early- or late-postemergence (POST) timings. The early POST treatments of Imiflex, Assure II, Zest, and Select Max alone or in tank-mixture with Weedar 64 and/or Clarity were also tested in a separate study. Among PRE programs, Imiflex tested at both rates provided an excellent control (89 to 94%) of green foxtail up to 50 days after PRE (DAPRE), whereas control did not exceed more than 51% with any of the group 15 herbicides. Among early POST programs, Assure II at 10 fl oz/a provided 95% green foxtail control at 28 days after early POST (DAEPOST). Green foxtail control with early POST treatments of Imiflex, Zest, and Assure II (6 oz/a) was moderate and ranged from 77 to 83% at 28 DAEPOST. Green foxtail control with late POST treatments of Imiflex, Zest, and Assure II was inadequate and ranged from 14 to 31% at 21 days after late POST (DALPOST). In a separate study, tank-mixing Weedar 64 or Clarity with Assure II reduced the efficacy by >50% on green foxtail control compared to Assure II alone treatment. These results suggest that PRE applied Imiflex (6 or 9 oz/a) can provide excellent residual activity for early season control of green foxtail. Furthermore, Assure II applied early POST at a higher rate can provide effective control of green foxtail; however, the efficacy will significantly decline if Assure II is tank-mixed with Weedar 64 or Clarity.

2020 Kansas State University Industrial Hemp Dual-Purpose and Fiber Trial

2020 Kansas State University Industrial Hemp Dual-Purpose and Fiber Trial

Selection of New Zoysiagrass Genotypes for Golf Course Fairways, Greens, and Tees in the Upper Transition Zone

A set of 70 experimental zoysiagrass genotypes along with three standards, ‘Meyer,' ‘Innovation,' and ‘KSUZ 1201,' were evaluated for turf performance in the northern transition zone. The genotypes were previously selected from a set of 935 progeny that resulted from pairwise crossings of cold-hardy zoysiagrass parents with fine-textured, under-utilized zoysiagrasses. All 70 progeny survived the winter of 2019–2020 and thus were evaluated based on their turf performance. The preference of selection was based first upon spring green up ratings, followed by leaf texture (finer preferred), vigor, turf quality, and wilt during dry down. A total of 20 best progeny were selected and harvested for propagation on October 12, 2020. Only one geno­type, ‘6844-31’ had a texture rating of 8.0 (1 to 9 scale; 9 = finest texture) and four other genotypes had texture ratings higher than 7.0 among the selected 20 best progeny. The progeny will be established in larger replicated plots at several locations including Kansas State University Olathe Horticulture Center, Olathe, KS, starting in the summer of 2021

Interaction of 2,4-D with Glyphosate or Graminicides on Grass Weed Control in Enlist E3 Soybeans

The introduction of Enlist E3 soybean allows growers to use postemergence (POST) applications of low-volatile formulations of 2,4-D choline (Enlist One) for in-season control of glyphosate-resistant weeds. The POST applications of Enlist One and glyphosate (Roundup PowerMax) mixture can be tank-mixed with clethodim (Select Max) or quizalofop (Assure II) for both grass and broadleaf weed control. However, reduced control of grass weed species has previously been reported when graminicides (Select Max or Assure II) are tank-mixed with auxinic herbicides (2,4-D or dicamba). The main objective of this research was to determine the effectiveness of Enlist One, Roundup PowerMax, Select Max, and/or Assure II alone or in various combinations on grass weed control in Enlist E3 soybean. Field experiments were conducted during the 2020 growing season at the Kansas State University Agricultural Research Center (KSU-ARC) near Hays, KS, and the University of Nebraska near Lincoln, NE (UNL). The dominant grass species at the KSU-ARC site were southwest cupgrass and green foxtail. The predominant grass species at the UNL site were giant foxtail, hairy cupgrass and fall panicum. Herbicide treatments, including Select Max, Assure II, and Roundup PowerMax applied at V3-V4 soybean stage alone or in combination with Enlist One; and sequential treatments of Enlist One followed by (separated by 5 days) Select Max, Assure II and/or Roundup PowerMax, and vice-versa were investigated. Results from the KSU-ARC site indicated that sequential treatment of Enlist One at 5 days prior to the application of Assure II provided the highest control (87% to 90%) of southwest cupgrass and green foxtail at 28 days after treatment (DAT). In contrast, control of both grass species did not exceed 78% with the rest of the treatments. Soybean grain yields ranged from 7 to 16 bu/a for the majority of the treatments. Results from UNL site showed that the addition of Enlist One to Select Max or Assure II or applied in sequential treatments at 5 days after the application of these graminicides reduced control of giant foxtail (69% to 79%), hairy cupgrass (70% to 79%), and fall panicum (69% to 79%) at 28 DAT compared to graminicides alone (93 to 97%). Furthermore, an addition of Roundup PowerMax to tank-mixtures of Enlist One with Select Max or Assure II improved the control of all three weed species. Soybean grain yields ranged from 21 to 55 bu/a for the majority of the treatments. In conclusion, these results support the hypothesis that Enlist One can compromise the efficacy of Select Max or Assure II; however, addition of Roundup PowerMax to these tank-mixtures can help to optimize grass weed control in Enlist E3 soybean.

Preliminary Classification of Soil, Plant, and Residue Cover Using Convolutional Neural Networks

In agricultural fields, knowledge about the proportion of the soil surface covered with crop residue and vegetation canopy is key for improving soil and water conservation practices. In this study we trained a deep convolutional neural network to automate the classification of bare soil, crop stubble, and live vegetation from downward-facing images of agricultural fields. A comprehensive generic dataset, consisting of 3300 training and 645 test images, was collected from agricultural fields across Kansas State University Agricultural Experiment Stations and the Natural Resources Conservation Service Plant Material Center located near Manhattan, KS. Despite the intricate patterns and color textures resulting from different combinations of soil, canopy, and stubble the trained network showed good performance for automating the classification of land cover from images. The network achieved 87% accuracy over the training dataset and 84% accuracy over the test set.

Registration of ‘KS Western Star’ hard red winter wheat

Abstract‘KS Western Star’ (Reg. no. CV‐1174, PI 693935) hard red winter wheat (Triticum aestivum L.) was developed by the wheat breeding program at the Agricultural Research Center–Hays, Kansas State University, and released by the Kansas Agricultural Experiment Station in 2019. KS Western Star was developed with the objectives to further improve drought tolerance, straw strength, and multiple disease resistance of currently available cultivars for western Kansas. KS Western Star was selected from a single cross ‘Byrd’/KS05HW121‐2 made in 2009. KS Western Star was developed as an F6–derived line using a modified bulk breeding method and was evaluated in yield trials from 2014 to 2019. It has medium maturity, medium height, and high grain volume weight, as well as high flour yield and good bread‐making quality. KS Western Star has good adaption to semi‐arid areas in western Kansas with its drought tolerance, stripe rust and leaf rust resistance, and improved lodging resistance.

Registration of ‘KS Dallas’ hard red winter wheat

Abstract‘KS Dallas’ (Reg. no. CV‐1173, PI 693934) hard red winter wheat (Triticum aestivum L.) was developed by the wheat breeding program at the Agricultural Research Center–Hays, Kansas State University, and released by the Kansas Agricultural Experiment Station in 2019. KS Dallas was selected from a three‐way cross KS08HW112‐6//TX03A0148/Danby TR made in 2009 at Hays, KS. The objective of this cross was to develop a hard winter wheat cultivar with adaptation to dryland production in western Kansas. KS Dallas was developed using a modified bulk breeding method. KS Dallas is an F6‐derived line and was tested in yield trials across Kansas for 4 yr. KS Dallas has medium maturity, medium height, and a medium‐long coleoptile. It has high grain yield potential in western Kansas and good resistance to the prevalent diseases including Wheat streak mosaic virus and leaf rust. It also has good bread‐making quality.

Registration of the wheat D‐genome nested association mapping (DNAM) population

AbstractModern wheat is lacking diversity in the D genome due to the genetic bottleneck from the hybridization between tetraploid Triticum turgidum L. and diploid Aegilops tauschii Coss. The D‐genome nested association mapping (DNAM) population (Reg. no. MP‐14, NSL 536301 MAP) was developed to expand D‐genome variation in hexaploid wheat (Triticum aestivum L.). The DNAM population is a wheat nested association mapping population developed with direct crosses between the hard‐white winter Kansas State University breeding line KS05HW14‐3 and Ae. tauschii accessions TA10187, TA1693, TA10171, TA1662, TA1617, TA1615, TA1642, and TA1718. In total, there are 1,164 BC₂F₄ recombinant inbred lines (RILs) in 19 families. The DNAM was originally created for introgression of novel stem rust resistance genes but has since been used to identify resistance to other fungal pathogens. A subset of 420 lines were selected for important agronomic traits, including height and threshability, and named the DNAM Core RILs. Research with the DNAM has potential to provide novel genes that can be introgressed into elite cultivars, as well as knowledge and understanding of the D genome in wheat.

PSI-5 Effects of rest period prior to processing on anthelmintic response during the receiving period in feedlot heifers

Abstract A major stressor affecting feedlot cattle performance is transportation. Knowing when to process cattle and how much rest to provide prior to processing may improve cattle health and response to processing, such as anthelmintic administration. The goal of this project was to determine the impact of time of rest prior to initial processing on parasite prevalence during the receiving period. Eighty mixed-breed heifers (250±4.2 kg BW) were purchased at live auction in Oklahoma City, OK and transported to the Kansas State University Beef Cattle Research Center in Manhattan. Heifers were allotted in a completely randomized design to one of four treatments processed at 0, 6, 24, or 48 hours after arrival. At processing (d 0), fecal samples were collected, and cattle were subcutaneously injected with 1.0 ml/50 kg BW moxidectin (Cydectin®, Bayer Animal Health, Shawnee Mission, KS) and orally dosed with 1.0 mL/50 kg BW oxfendazole (Synanthic®, Boehringer Ingelheim, St. Joseph, MO). Fecal samples were collected again on d 14. Fecal samples were analyzed by the Kansas State University Veterinary Diagnostic Laboratory for qualitative and quantitative fecal float. Time of processing did not impact (P > 0.05) any measured response criteria. On d 0, there was a high prevalence of fecal parasites, which was significantly reduced by d 14 (94.5% vs. 23.1% of cattle with detected fecal parasites on d 0 vs. 14, respectively). On d 0, semi-quantitative density showed the highest concentration of strongyle and eimeria parasites, which were significantly reduced (P < 0.05) by d 14 (315 and 155 vs. 2 and 6.5 eggs/g of feces detected for strongyle vs. eimeria, respectively). In summary, time of rest prior to processing had no detected impact on anthelmintic response, but the dual injection/oral protocol used in this experiment was highly effective at reducing parasite levels within 2 weeks of administration.

PSVII-12 Acceptability of Milne blueberry juice and blueberry puree in horse feed

Abstract The objective of this study was to evaluate the impact of liquid blueberry juice (BJ65) or blueberry puree (BP30) used as a binding agent on pellet durability and palatability of a typical equine concentrate when included at 4% of the pellet. Molasses was used as a control. Production data, pellet durability and moisture content were evaluated in 1 replicate for each treatment. Because moisture content of condition mashes were 17.59% and 18.11% for BJ65 and BP30 treatments, respectively, greater inclusion of blueberry product would likely cause roller slippage and complicate the pelleting process due to increased liquid (Fahrenholz, 2012). Pellet durability met industry standards for all treatments. Pellets were fed in a 3 x 3 Latin square design to 9 two-year-old horses to determine the effect of blueberry products on acceptability. All animals were allowed 10 minutes to consume 1.36 kg at 0700 h and 1700 h each day for 3 d. Consumption time and amount consumed were recorded to calculate intake, intake rate, and intake ratio (IR). No horse consumed all pellets within the allotted time, and thus, there were no differences between intake rate and intake. Period tended to impact intake (P = 0.0909), with horses consuming less during period 1 than period 3 (P = 0.0317), but period had no effect (P = 0.2881) on IR. Treatment influenced intake (P < 0.0001), with decreased intake of BP30 compared to control and BJ65 (P ≤ 0.0001). Intake ratio was greater (P = 0.0075) for BJ65 than BP30 with IR of 0.5069 and 0.4227, respectively. Consumption of BJ65 was no different than control. Fahrenholz, A. 2012. Evaluating factors affecting pellet durability and energy consumption in a pilot feed mill and comparing methods for evaluating pellet durability. Doctoral thesis. Kansas State University, Manhattan, KS.

PSI-6 Effects of rest period prior to processing on vaccine response and blood metabolites in feedlot heifers

Abstract It is common for feedyards to rest cattle after transport and prior to administration of their receiving vaccinations in an attempt to minimize transport stress and optimize vaccine efficacy and subsequent growth and performance. This study aimed to test how time of rest after feedlot heifer arrival impacts vaccine titer and blood metabolites indicating cattle health. Eighty mixed-breed heifers (250 ± 4.2 kg BW) were purchased at live auction in Oklahoma City, OK and transported to the Kansas State University in Manhattan. Heifers were allotted in a completely randomized design to one of four treatments processed at 0, 6, 24, or 48 hours after arrival. At the time of processing (d 0) and again on d 35, serum samples were collected and analyzed for infectious bovine rhinotrachitis (IBR) titer, large animal chemistry panel, and hepatic profile by the Kansas State Veterinary Diagnostic Laboratory. There were time × treatment interactions (P < 0.02) for serum IBR titer, glucose, urea nitrogen, and bicarbonate. Specifically, heifers had greater (P < 0.05) IBR titer on d 35 than d 0, as expected because they were vaccinated upon arrival. Upon arrival, cattle held for 48 hours prior to processing had significantly greater (P < 0.05) glucose than those held for 24 hours (108 vs. 68 mg/dL, respectively), with no differences in processing treatment by d 35. Urea nitrogen levels in cattle held for 6, 24, or 48 hr prior to processing were greater (P < 0.05) than those held for 0 hours on d 0 or for any length of time by d 35. Finally, cattle held for 0 or 48 hr prior to processing had lower (P < 0.05) bicarbonate levels on d 0 than those held for 6 or 24 hours by d 35. These data show that while initial rest may be helpful to normalize blood metabolites, cattle should be placed within 24 hours of arrival. However, most blood metabolite levels normalize within 35 days.

57 Effects of rest period prior to processing on growth and performance during the receiving period in feedlot heifers

Abstract Cattle feeders work to decrease the severity of transport stress. The objective of this experiment was to determine how the time of rest prior to processing impacts subsequent performance in feedlot heifers during the receiving period. Eighty mixed-breed heifers (250 ± 4.2 kg BW) were purchased at live auction in Oklahoma City, OK and transported to the Kansas State University Manhattan. Heifers were allotted in a completely randomized design to one of four treatments, then processed at 0, 6, 24, or 48 hours after arrival. After all cattle were processed, they were placed in individual pens, where daily DMI, refusals, and health outcomes were evaluated twice daily. Cattle were individually weighed on d 0, 14, and 35. Data were analyzed using the GLIMMIX procedure of SAS (v. 9.4, Cary, NC). Time of processing did not impact (P > 0.10) heifer body weight or ADG. Overall, there was a linear inverse relationship between DMI and time at rest (P = 0.027) from d 0 to 14. The same pattern was observed overall, from d 0 to 35 (P = 0.027). Time of rest prior to processing impacted (P = 0.038) the proportion of heifers that reached a target of 2.5% DMI per BW by 14 days after arrival (25, 60, 53, and 24% of cattle with 0, 6, 24, or 48 hours of rest, respectively). While G:F and morbidity did not differ among treatments (P > 0.10), mortality increased linearly (P = 0.026) with increasing time of rest. This study suggests that allowing feedlot heifers to rest after arrival for more than 24 hours before processing may negatively affect subsequent DMI, but without substantially altering body weight or ADG in calves fed in individual pens; additional research in traditional feedlot group-housed pens and environment is warranted to further evaluate these effects.

PSIII-13 The Effects of Corn Gluten Feed and Corn Dried Distillers Grains as a Replacement for Soybean Meal on Boer Type Goat Diets

Abstract The objective of this study was to evaluate the efficacy of corn dried distillers grains with solubles (DDGS) or corn gluten feed (CGF) as a replacement for soybean meal (SBM) in a Boer goat diet. A total of 75 meat goat kids (26.9 0.2 kg) were placed in 25 pens (3 kids per pen and 5 pens per treatment) for a 35-day experimental period at the Kansas State University Sheep and Meat Goat Center. Kids were allotted to one of the following isocaloric and isonitrogenous diets that varied in protein source: 1) SBM; 2) 100% DDGS/0% CGF; 3) 66% DDGS/33% CGF; 4) 33% DDGS/66% CGF; and 5) 0% DDGS/100% CGF. Diets were pelleted and supplied the sole source of nutrition. Goats and feeders were weighed weekly to determine ADG, ADFI, G:F, cost per kg of diet, and cost per kg of gain. Data were analyzed using the GLIMMIX procedure of SAS (SAS Inst., Cary, NC) with pen serving as the experimental unit. Differences were considered significant if P0.05. Treatment did not impact BW (P = 0.999), ADG (P = 0.723), ADFI (P = 0.210), or G:F (P = 0.796; Table 2). While diet cost differed due to differences in price of soybean meal and the corn co-products, there was no evidence (P = 0.941) that cost per kg of gain was less for goats fed the corn co-products. However, feed cost per goat was less (P = 0.0008) with diets containing corn co-products, regardless of level. These data allow producers to make more informed feeding decisions with a broader understanding of potential implications of corn gluten feed use in goats.