bluuebunny/crossref_metadata_2025 huggingface dataset:
257 Young Scholar Presentation: Using an integrated systems biology platform to determine the mode of action of feed additives in nursery pig diets
Authors: Trudeau Michaela , Tran Huyen , de Rodas Brenda , Karnezos Theodore , Gomez Andres , Chen Chi , Urriola Pedro E , Shurson Gerald C
Published: November 2020

The mechanisms of action for antibiotic growth promotion are poorly understood, making it difficult to select effective alternatives that are capable of providing similar responses. In order to evaluate the complete impact of supplementing antibiotics and other feed additives to nursery pigs, an integrated systems biology platform encompasses the merging of traditional nutrition models with gut physiology, nutrition and omics technologies. The objective of this study was to evaluate the growth response, metabolic responses, and intestinal microbiome composition of nursery pigs fed antibiotics. Antibiotic diets containing chlortetracycline and sulfamethazine (AB), and diets containing no antibiotics (CON) were fed in 3 trials. Pigs were weighed at d 10, 21, and 42 post-weaning and ADG, ADFI, and G:F was calculated. On d 42, one pig/pen was selected for blood, cecal, and ileum content collection to assess metabolomic profiles via liquid chromatography-mass spectrometry. The composition of bacterial communities in those samples was determined by sequencing the V4 region of the 16s rRNA bacterial gene in the MiSeq platform. Metabolomics and microbiome data were analyzed using multivariate approaches and growth performance data were analyzed using a generalized mixed model. Pigs fed AB were heavier (P < 0.05) on day 42. There were also significant differences (P < 0.05) in the cecal and serum metabolite profile of pigs fed AB compared with CON. However, there were no changes in bile acid or short chain fatty acid concentrations in cecal samples when feeding AB. Although AB had no effect on alpha or beta microbiome diversity, the abundance of specific bacterial taxa shifted significantly (P < 0.05). These findings suggest that feeding antibiotics improve growth, alter metabolism, and affect the abundance of specific taxonomic groups of bacteria in the gut. In the future, this approach will be utilized to evaluate antibiotic alternatives for nursery pigs.
283 Performance and mineral fecal excretion of post weaned piglets are influenced by different sources of zinc oxide
Authors: Moita Vitor Hugo C , Abreu Márvio L , Silva Bruno N , Chaves Rhuan , Tolentino Ronaldo Lucas S , Gonçalves Mateus F , Lima Valesca
Published: November 2020

The study aimed to evaluate the impact of the supplementation on post weaning diets of the conventional source of zinc oxide (ZnO) and/or a potentiated source of zinc oxide (PZnO) and different (P) levels on productive performance, incidence of diarrhea, (Zn) and (Cu) fecal excretion. Eighty-four pigs weaned at 21 days of age were allocated in a randomized block design with four dietary treatments [T1: no inclusion of ZnO and regular P levels (0.440%; 0.420%; 0.400%; 0.380%); T2: inclusion of ZnO and regular P levels (0.440%; 0.420%; 0.400%; 0.380%); T3: ZnO and PZnO and 10% low P levels (0.396%; 0.379%; 0.360%; 0.340%); T4: inclusion of the PZnO and 10% low P levels (0.396%; 0.379%; 0.360%; 0.340%)], with seven replications and three pigs/pen. The nutritional program was: (pre-starter 1: d 21 to 28; pre-starter II: d 28 to 35; starter I: d 35 to 49; and starter II: d 49 to 63). The Tukey test was adopted to compare the means (SAS, 9.3). From d 1 to 14, T2 improved ADG (P < 0.05) and BW (P < 0.05) at d 14. From the period of d1 to d28, pigs fed with T2 diets showed higher ADG (P < 0.05), ADFI (P < 0.05) and, consequently, higher BW (P < 0.05) at d 28. From d 1 to 42, pigs fed with PZnO diet performed the highest ADFI (P < 0.05). Evaluating overall data of diarrhea, T2 reduced the incidence of diarrhea (P < 0.05). T4 reduced Zn and P fecal excretion during the period from d 7 to 28 (P < 0.05). Therefore, the use of ZnO and PZnO provide the same performance results of piglets on the period from d 1 to 42 after weaning. Furthermore, the inclusion of PZnO reduces the Zn and P fecal excretion.
30 Uterine flushing as a non-invasive method to access inflammatory cytokines in sows reproductive tract after parturition
Authors: Garcia Ricardo M , Stewart Kara R , Radcliffe John S , Schinckel Allan P , Richert Brian T
Published: November 2020

Inflammatory mediators, such as cytokines, can reduce feed intake and drastically modify the partitioning of nutrients. Thus, it may increase the animal’s maintenance requirements, reduce milk production and piglet growth, impact reproductive performance, and reduce sow lifetime productivity. The objective of this experiment was to evaluate a non-invasive method, not tested before in swine, to assess cytokine profiles from post-partum uterine lavage. The uteri of second and third parity sows (n=14) were flushed with sterile saline solution (0.9%) on days 2, 4, and 14 post-parturition. An artificial insemination (AI) catheter, in its plastic covering, to avoid vaginal contents, was inserted through the vagina into the cervix. A flexible inner catheter was passed through the outer AI catheter and into the uterine horn. Sterile saline (30-40 mL) was flushed through the inner catheter into one uterine horn. After inner catheter removal, a tube was attached to the end of the outer AI catheter to allow collection of the natural back-flow of uterine lavage fluid (avg 24.7% recovery). Uterine fluid collected was immediately centrifuged and the supernatant stored at -20°C. Samples were freeze-dried, re-suspended in sterile saline (2 mL), and stored at -80°C. Cytokine profiles of the uterine fluid were evaluated using a multiplex ELISA panel including interleukin (IL)-1β, IL-6, IL-8, IL-4, IL-10, tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ). Cytokine concentrations were calculated relative to protein content (pg/mg of protein). IFN-γ and TNF-α were lower than the limit of detection in most samples (5/38 and 1/38, respectively). IL-4 and IL-10 concentrations did not differ among days of collection (P >0.14). IL-8 was greater on day 4 than on days 2 or 14 (P< 0.05). IL-1β and IL-6 were greater on days 2 and 4 than on day 14 (P< 0.05). Uterine flushing is a novel non-invasive method to access uterine inflammatory cytokines in sows.
238 Linking livestock phenomics and precision livestock farming
Authors: Juarez Manuel M
Published: November 2020

Numerous pre- and post-mortem factors, such as genotype, production system, growth promotants, diet, health events, stress, slaughter age and weight, carcass chilling, and ageing time, have been shown to impact beef production and final product quality. The objective of livestock phenomics is the systematic acquisition of high dimensional phenotypic data, which requires measuring phenomes as they change in response to genetic mutation and environmental influences. Due to the decrease in costs associated to genomics technology and related fields, researchers had to face the so called “phenomic gap”, a lack of sufficient, appropriate phenotypic data. Selecting phenotypes of interests, standardizing methodologies, developing high-throughput data collection systems, systematically recording environmental factors, and integrating bioinformatics are some of the challenges when developing a livestock phenomics program. Precision livestock farming aims at applying continuous, automated real-time monitoring systems to optimize livestock management. The information collected by these systems can be used to optimize individual animal health and welfare, reproductive traits, and productivity, as well as environmental influences. This approach requires the use of novel technologies and the management of large amounts of data. Multiple technologies and sensors are already being used, or have the potential, to monitor important individual traits. These two interdisciplinary fields share multiple objectives that could lead to significant synergies. The complexity of in-farm data collection varies depending on the species and production system, with beef cattle presenting specific challenges. In addition, data collection needs to continue after slaughter, as carcass and meat quality traits are influenced by in vivo practices, determine the final profitability of the system, and need to be taken into consideration to modify management practices. Integrating livestock phenomics and precision livestock farming approaches will lead to a faster development of both fields and an optimal use of resources.
103 Effect of a single Revalor-XH or Revalor-200/Revalor-200 re-implant program and zinc supplementation on performance, carcass characteristics, and liver mineral of feedlot heifers
Authors: Messersmith Elizabeth M , Niedermayer Emma , Crawford Grant , Hansen Stephanie L
Published: November 2020

A 169-d study utilizing 208 Angus-cross heifers (291 ± 23 kg; 4 sources) in a 2×2 factorial examined the effects of implant strategy and Zn supplementation on growth and mineral status of heifers. Factors included 2 implant (Merck Animal Health, Madison, NJ) strategies: extended-release Revalor-XH on d 0 (REV-XH; 20 mg estradiol+200 mg trenbolone acetate) or Revalor-200 on d 0 and 91 (REV-200; 20 mg estradiol+200 mg trenbolone acetate) and 2 supplemental Zn (mg/kg dry matter [DM]; ZnSO4) strategies: national (30; NRC) or industry (100; IND) recommendations. Heifers were blocked by weight within source (n = 5 or 6 heifers/pen; 9 pens/treatment), received a corn silage-based diet (d 0-56), then transitioned to a corn-based diet fed via concrete bunks. Data were analyzed in Proc Mixed of SAS; fixed effects of implant (IMP), Zn, interaction, and source with the repeated effect of time for average daily gain (ADG) and liver mineral. Initial weight served as a covariate for performance and carcass data. Revalor-200 had greater ADG from d 0-28 and 91-120, while REV-XH peaked during d 56-91 (IMP × time; P = 0.02), corresponding to likely periods of greatest hormone payout from each implant. Liver Mn concentrations decreased on d 14 regardless of implant while d 105 and 164 concentrations were lesser for REV-200 (IMP × time; P = 0.02). Hot carcass weight, DM intake, carcass-adjusted ADG and feed efficiency were not different between IMP strategies (P ≥ 0.18). Steers fed IND tended to be heavier on d 91 (P = 0.06) and were heavier on d 120 (P = 0.05) than NRC; however, final BW did not differ due to Zn (P = 0.37). The similar performance between implant strategies and superior performance during peak hormone payout by heifers supplemented IND vs. NRC suggests increased Zn may support rapid growth.
225 Effects of late gestation Calcium salts of fatty acids supplementation to beef cows on offspring pre-weaning growth performance and gene expression
Authors: Shao Taoqi , Ireland Frank , Mccann Joshua , Shike Daniel W
Published: November 2020

Objectives were to investigate the effects of supplementing Ca salts of fatty acids to beef cows during late gestation on the pre-weaning growth performance and gene expression of steer progeny. Ninety-six fall-calving, Angus x Simmental cows (BW = 601±76 kg) were randomly assigned into 8 pastures (4 pastures/treatment; 12 cows/pasture), supplemented soyhulls mixed with 80 g/cow/d Strata + 80 g/cow/d Prequel (PUFA, rich in linoleic acid, eicosapentaenoic acid, and docosahexaenoic acid) or 155 g/cow/d EnerGII (SFA/MUFA, rich in palmitic and oleic acids) for 76.5±6.0 d prepartum. Cow/calf pairs were comingled after calving. Biopsies of Longissimus dorsi (LD) and subcutaneous adipose were taken at birth and 3 wk before weaning (186±6 d). The data were analyzed using the MIXED procedure of SAS. Supplementing PUFA increased (P < 0.01) cow plasma eicosapentaenoic acid and docosahexaenoic acid at midpoint of supplementation. At birth, PUFA steers had greater (P < 0.05) plasma EPA and lower (P < 0.01) plasma linolenic acid and oleic acid than SFA/MUFA steers. Weaning BW and pre-weaning ADG of the SFA/MUFA steers tended (P < 0.07) to be greater than PUFA steers. SFA/MUFA steers had increased (P = 0.04) expression of Zfp423 in adipose. There tended to be a treatment×time interaction (P = 0.06) for expression of Myf5 in LD; expression of Myf5 was greatest in SFA/MUFA steers at birth. There was a treatment×time interaction (P = 0.05) for expression of Pax7; expression was greater in SFA/MUFA steers at birth than any treatment at weaning. There were treatment×time interactions (P < 0.01) for expression of Myh7 and C/EBPβ in LD; expressions were greatest in PUFA steers at weaning. Supplementing Ca salts of PUFA to beef cows during late gestation altered plasma fatty acid profile of cow and calf, affected gene expression, and decreased offspring growth performance.
249 Evaluation of FluidQuip Dried Distillers Grains plus Solubles in Cattle Finishing Diets
Authors: Wiseman Aksel , Boyd Brad , McPhillips Levi , Tilton Scott , Watson Andrea K , Erickson Galen E
Published: November 2020

A 112 d finishing study was conducted to evaluate the effects of feeding dried distillers grains plus solubles (DDGS) from the MSC-Fiber stream of the FluidQuip post-fermentation fiber separation process compared to conventional DDGS. Yearling crossbred steers (n = 240, initial BW = 463 ± 35kg) were blocked by initial BW, stratified by BW, and assigned randomly to pen (n = 30; 8 steers/pen). Treatments were arranged as a 2×2 + 1 factorial with DDGS type (MSC DDGS [MSC]; Conventional DDGS [CONV]) and inclusion level (20 or 40% diet DM) as the factors. All treatments were compared to a corn-based control (CON). DDGS replaced a 60:40 blend of high-moisture corn and dry-rolled corn. All diets contained 7.5% alfalfa hay and supplement. Data were analyzed as a randomized block design with pen as experimental unit and block as fixed effect. Increasing concentrations of CONV or MSC resulted in a linear increase in DMI (P < 0.01). Steers fed 40% MSC had the greatest DMI (P < 0.01) while CON steers had the least (P < 0.02). Daily gains for MSC steers linearly increased (P = 0.03), while CONV steers showed a tendency for a quadratic response to ADG (P=0.08). Feed efficiency of CONV steers increased quadratically (P = 0.04) and tended to decrease linearly (P = 0.09) for steers fed MSC. Efficiency was greatest for 20% CONV but not different (P > 0.16) than CON, or 20% MSC. Steers fed 40% MSC or 40% CONV were not different in feed efficiency. Inclusion of MSC DDGS resulted in linear increases in DMI and ADG over CON, but decreased feed efficiency by 1.0 and 5.3% resulting in MSC DDGS having a relative feeding value of 95.0 and 86.7% of corn at 20 and 40% DM, respectively.
140 Young Scholar Presentation: Immune activation and its effects on energetics and calcium homeostasis
Authors: Horst Erin A , Baumgard Lance H
Published: November 2020

Nutrient partitioning towards productive processes (i.e., milk production, growth, and reproduction) is key to economically profitable agriculture. During immune activation, the hierarchy of coordinated nutrient trafficking is reprioritized towards the immune system at the expense of production. Dairy cows encounter frequent immune challenges, as bacterial insults can originate from a myriad of sources including the uterus, mammary gland, and gastrointestinal tract. Regardless of the origin, immune activation hinders animal welfare and evidence suggests it may play a role in many post-calving undesirable phenotypes (i.e., decreased DMI, increased NEFA, hypocalcemia). Following activation, leukocytes undergo a metabolic shift from oxidative phosphorylation to aerobic glycolysis (a phenomenon known as the “Warburg effect”) and begin consuming copious amounts of glucose. In a lactating cow the glucose requirement of the acutely activated immune system exceeds 1 kg in a 12-hour period. To ensure adequate glucose delivery to leukocytes several well-characterized metabolic adjustments are employed including hyperglycemia or hypoglycemia (depending on the stage and severity of infection), increased insulin and glucagon, increased skeletal muscle catabolism, hypertriglyceridemia, and hypoketonemia. The energetic burden of immune activation is intensified by a simultaneous decrease in feed intake and thus reduced intestinally derived substrates. In addition to energetic metabolism, immune activation induces a marked and sustained decrease in circulating calcium (Ca). Recently, we have demonstrated that the total Ca deficit was ~20 g during an acute (12 hour) and intense model of immune activation. Infection-induced hypocalcemia is a species conserved response, yet, it remains largely unknown what role Ca plays during infection and why it acutely decreases. Although, evidence suggests it may serve as a protective strategy to prevent a hyper-inflammatory systemic response during infection. In summary, immune activation negatively influences metabolic, hormonal, and Ca homeostasis and these alterations closely mimic changes observed in poorly transitioning dairy cows. Having a better understanding of the impact of immune activation on nutrient trafficking and Ca homeostasis will provide foundational information for developing strategies aimed at minimizing production losses during infection.
154 A genetic marker for PRRS resistance has no adverse effect on economically important traits in pigs
Authors: Zhang Chunyan , Thekkoot Dinesh , Kemp Bob , Dekkers Jack , Plastow Graham
Published: November 2020

Porcine Respiratory and Reproductive Syndrome (PRRS) is a very costly viral disease of pigs. A genetic marker for host response to PRRS on chromosome 4 (rs80800372, (WUR)) could be used to select for resilience to PPRS. However, before including WUR in selection, it is necessary to know effects of WUR on economically important traits without PRRS. A dataset with both genotypes and phenotypes on purebred Duroc (D), Landrace (L), Yorkshire (Y) and crossbred (LY or DLY) pigs was used. A total of 20 traits were tested. Sow reproduction and litter traits were available on > 13,000 D, L and Y and 1,549 LY sows. Growth and ultrasound traits were recorded on >35,000 D, L and Y and 2,622 DLY pigs. Daily feed intake (70-120kg) was from 4,133 Durocs. Carcass and meat quality traits were from 2,184 Durocs, 1,160 Yorkshires and 2,184 DLY pigs. All animals were genotyped using a custom SNP chip ( > 55K) including WUR. Analyses were done within each breed using an animal model. WUR was fitted as a fixed effect by classifying pigs with one or two favourable alleles (B) into one group and others into a second group. Contemporary group, parity, litter, lactation length and net fostering effects were considered depending on the traits. Relationship matrices were constructed using pedigree in purebreds and genotypes in crossbreds. WUR had no significant ( P >0.05 ) effect on any trait, except for number of pigs alive at 24hrs in Y and ultrasound loin depth in D and Y ( P< 0.05 ) but the favorable WUR allele also had favorable effects on these two traits. These results were similar to the report by Dunkelberger et al. (J. Anim. Sci. 2017, 95: 2838). In conclusion, WUR had no adverse effects on any trait and can be used to select pigs with increased resilience to PRRS.
69 Connecting with the next generation of shepherds – an online sheep-based webpage serves as an additional tool in Extension education
Authors: Campbell Braden J , McCutcheon Jefferson S , Fluharty Francis L , Parker Anthony J
Published: November 2020

Cooperative Extension education continues to maintain a strong foothold in educating people in the agricultural industry. To connect with the next generation of agriculturalists, Extension needs to investigate alternative methods to disseminate educational material. Developing and maintaining a webpage that provides relevant and scientific based sheep production information is critical as interest in the small ruminant industry continues to rise. The Ohio State University Extension Sheep Team webpage provides shepherds across the nation with the latest information regarding sheep production from daily management to industry outreach. In addition, a unique highlight of the webpage includes research summaries of sheep research conducted at Ohio State that are simplified to illustrate real-world application to improve on-farm production efficiencies. Over the past year alone, the OSU Extension Sheep Team webpage has recorded over 90,000 page views with an average visit duration time of approximately two minutes. Of these page views, approximately 9,000 originate from locations beyond the United States including Canada, United Kingdom, Australia, and New Zealand. According to the web servers’ descriptive statistic analysis, the top referral search engine is Google, representing 58% of all page visits. Interestingly, due the OSU Extension Sheep Team’s presence on social media, Facebook accounts for approximately 18% of all page visits whereas direct subscription of the weekly newsletter only accounts for 15% of all page visits. Furthermore, top article topics include those that relate to basic sheep management practices, health and disease, parasite control methods, and common poisonous plants. Due to the unusual weather patterns of 2019, an article related to poisonous plants accounted for 16% of the webpage’s total visits, which surpassed the number of homepage visits. In order to continue providing relevant Extension information, universities should consider utilizing web-based articles to efficiently reach a larger audience and provide timely articles based upon viewer interest.
55 Rumen undegradable protein content of native range and sub irrigated meadow forages
Authors: Wheeler Kaylee E , Klopfenstein Terry J , MacDonald James C , Watson Andrea K , Wilson Hannah C
Published: November 2020

The in situ mobile bag procedure was used to compare rumen undegradable protein (RUP) content and RUP digestibility of Nebraska Sandhills range and meadow diet samples. Meadow samples (n = 12) were from June, July and August of 2 years while range samples (n = 19) were from June, July, September and December of 6 years. Samples were collected using esophageally fistulated cows (samples from 2 cows composited per time point), freeze-dried, and ground through a 2 mm screen. For each sample, 1.25 g was weighed into 8 replicate 8×10 cm Dacron bags with 50-µm pore size. Rumen incubation time was based on estimated digestibility and passage rate. Following rumen incubation, analysis of neutral detergent insoluble N (NDIN) on one-half of the bags was used to calculate RUP content. Remaining bags were treated with pepsin/HCl solution (37 °C) and stirred for three hours before duodenal incubation. Analysis of NDIN after recovery from feces determined RUP digestibility. Data were analyzed using month as a fixed effect and year and experiment as random effects. In meadow samples, CP (15.0% of DM) was consistent across June, July, and August (P = 0.72). Range samples tended to differ in CP content (P = 0.11), with June, July and September being similar (8.15% of DM) while December was 6.01%. In meadow samples, RUP averaged 21.9% of CP while range samples averaged 26.7% of CP, with no differences due to month (P ≥ 0.32). Because CP content was changing in range samples, RUP as a % of DM tended (P = 0.14) to decrease in December (1.66) compared to June, July, and Sept (2.25). In meadow samples, RUP digestibility (%) declined from 74.7% in June to 61.4% in July and Aug (P = 0.07). RUP digestibility (%) averaged 43.9% for all range samples (P = 0.66).
57 Effects of rest period prior to processing on growth and performance during the receiving period in feedlot heifers
Authors: Buessing Zachary , Tarpoff A J , Theurer Miles , Jones Tom , Jones Cassandra K
Published: November 2020

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.
PSV-8 Glucocorticoid receptor agonist (GRA): what is the best delivery method to newly weaned pigs?
Authors: Wooten Hailey , Kim Hwanhee , Rakhshandeh Amanda , Rakhshandeh Anoosh
Published: November 2020

We previously found that i.m. injection of GRA, similar to in-feed antibiotics, improves measures of intestinal integrity, nutrient digestibility, and overall growth performance in nursery pigs. In addition, we have demonstrated that the mitigating effects of GRA on the stress of weaning is predominantly done by subsiding the inflammatory response that often accompanies early weaning. The objective of the current study was to explore the most practical methods for delivering GRA to newly weaned pigs. One-hundred and sixty-seven PIC pigs were weaned at 25 ±1.0 days of age (BW 7 ±1.2 kg), and assigned to fourteen treatments (3-4 pigs /pen; 3 pens/treatment). Seven treatments were tested within two sexes (gilts vs. barrows). The treatments were: 1) i.m. injection of GRA (two injections, 0.2 mg/kg BW at -1 and 3 d post-weaning), 2) two levels of in-water GRA (0.8 and 1.6 ppm), 3) in-feed GRA (2.5 and 5.0 ppm), 4) in-feed antibiotic (ANT, 100 ppm tylosin), and 5) control. Dexamethasone was used as GRA. Pigs had free access to in-feed or in-water GRA or ANT during the 1st-week post-weaning. Parameters of growth performance were measured weekly until the end of the nursery phase. A completely randomized design and repeated measurement ANOVA (PROC MIXED) in SAS were used for statistical analyses. In-water, in-feed, and i.m. GRA treatments resulted in growth performance outcomes comparable to that of in-feed ANT. Relative to CON pigs, both ANT and GRA improved ADG and G: F during the nursery phase (P < 0.05). Among the delivery methods tested, 2.5 ppm of in-feed GRA resulted in superior ADG (GRA vs. CON; 0.29 vs. 0.20 kg/d) and G: F (0.63 vs. 0.40 ± 0.05), compared to the control group (P < 0.02). Collectively, these results suggested that in-feed treatment is the best method for delivering GRA to newly weaned pigs.
PSV-18 The role of leptin in feed efficiency and behavior attributes of commercial beef heifers
Authors: Bhowmik Nayan , Ringwall Kris A , Dahlen Carl R , Swanson Kendall C , Clapper Jeffrey A , Ward Alison K , Hulsman Hanna Lauren L
Published: November 2020

Leptin is a 16-kDa-peptide hormone product of the leptin gene (LEP) that is predominantly synthesized by adipose tissues and has known involvement in regulation of feed intake, energy expenditure, reproduction, and immune functions. The objective was to determine the association of leptin genotype (LEP c.73C >T), leptin diplotype (LEPD) and plasma leptin hormone (LEPH) concentration with growth, feed intake, feed efficiency, and behavior characteristics in developing beef heifers. A total of 336 commercial beef heifers were genotyped for the LEP c.73C >T marker. Four single nucleotide polymorphism markers including LEP c.73C >T, ARS-BFGL-NGS-59298 (intron 1), BovineHD0400026029 (upstream) and BovineHD0400026063 (downstream) of LEP were considered for haplotype analysis. Eleven LEPD were identified for this study using parsimony-based analyses. Circulating levels of LEPH were measured on 333 heifers prior to their first breeding season and used to assign low or high concentration group based on population median. Data were analyzed using the mixed procedure of SAS for repeated measures, fixed effects of ancestral breed group (n = 4), dam age category (n = 4), frame size group (n = 4), project cycle nested within birth year (n = 6), week of feed trial × year, LEP (n = 3) or LEPD (n = 11) or LEPH (n = 2), as well as week × LEPH (only for LEPH). There were no significant differences between LEP genotypes (P ≥ 0.11) or LEPD (P ≥ 0.33) for any of the studied traits. Heifers with low LEPH ate fewer meals per day (P = 0.02) and had more DMI per meal (P = 0.04) compared to those with high plasma leptin. Further research is needed to better understand plasma LEPH concentration and its role in feeding behavior attributes. However, circulatory LEPH before the breeding season may serve as a predictor for feeding behavior.
PSVI-12 Phosphorous digestibility of corn ethanol co-products, from Brazil and USA, in growing pigs
Authors: Paula Vinicius R C , Milani Natália C , Azevedo Cândida P F , Casarotti Gabriel A G , Granja Leonardo A , Mike Brian , Shurson Gerald C , Ruiz Urbano S
Published: November 2020

The objective of this study was to determine the apparent total tract digestibility (ATTD) and the standardized total tract digestibility (STTD) of P, and their respective digestible values, of two high protein (HP) corn dried distillers’ grains (DDG) and of two corn DDG with solubles (DDGS), from Brazil and USA, in pigs. Fifty crossbred barrows (38.3±5.2kg BW) were fed a semi-purified P-free basal diet (BD), used to determine endogenous P losses, or four diets composed of 40% of each ingredient, as the only source of P, substituting for starch in BD: Brazilian HP DDG (BHP); USA HP DDG (UHP); Brazilian DDGS (BDG) and USA DDGS (UDG). Animals were fed at 2.8 x maintenance (110 kcal of DE per kg of BW0.75) for 9 d (7 d adaptation and 2 d of partial feces collection). Titanium dioxide was used as an indigestible marker (0.3%) for digestibility calculations. A randomized block design was used, with 10 replicates, using the pig as the experimental unit. Results were submitted to ANOVA and Tukey’s test (P< 0.05). The ATTD of P of UHP and UDG were 47% greater (P< 0.05) than those verified in BHP and BDG. The STTD of P of UHP and UDG were 45% higher (P < 0.05) than that of BDG. The STTD of BHP was similar (P >0.05) to the values of BDG and UDG. The total and standardized digestible P of UDG (0.40-0.44%, respectively) were greater (P< 0.05) than those of BDG (0.33-0.38 %, respectively) and of UHP (0.28-0.32%, respectively), which were similar (P > 0.05), and higher than that of BHP (0.22-0.27%, respectively). In conclusion, corn distiller’s co-products from Brazil and USA presented different ATTD and STTD P values, and USA DDGS (UDG) showed the highest apparent total tract and standardized digestible P among all corn coproducts evaluated.
PSVIII-15 Phytogenics reduces medical treatment in nursery pigs affected by post-weaning diarrhea
Authors: Moran Kory , Aumiller Tobias , Manner Klaus , Zentek Jurgen , van der Klis Jan Dirk , Muller Andreas
Published: November 2020

This study evaluated the effects of phytogenics on performance, stool firmness, mortality and morbidity of weaned pigs housed in a commercial farm with historic incidence of post-weaning diarrhea associated with pathogenic E. coli. A total of 540 pigs (BW 7.34±0.9kg;) were used in a 42-day trial. Pigs were allotted by BW and sex into 30 pens (18pigs/pen). Pigs were fed a 2-phase feeding program, with each period being 14 and 28-d, respectively. Dietary treatments were: 1) Control and 2) Phytogenics (1,000 ppm Fresta®Protect, Delacon Biotechnik GmbH). Fecal score was determined daily by pen during the first 14-days (1=liquid diarrhea; 2=pasty feces; 3=formed feces; 4=well-formed feces; 5=hard feces). At day 42, fecal samples (n=15) were analyzed for copy numbers of the virulence factor genes fae (F-4 fimbria) and est-II (heat-stable toxin) by qPCR. Growth performance was not affected by treatments during phase 1. The ADG during phase 2 and overall period increased for pigs supplemented with phytogenics compared to control treatment (531 vs 501 g, P=0.015; 394 vs 375 g, P=0.025; respectively). Consequently, phytogenics tended to improve feed conversion during phase 2 and overall period compared to control treatment (1.48 vs 1.52, P=0.08; 1.46 vs 1.50, P=0.10). Phytogenics improved fecal score (3.8 vs 3.6, P< 0.001), livability (97.4% vs 96%) and decreased the percentage of pigs that required medicine to control post-weaning diarrhea (1.8% vs 2.9%) compared to the control treatment. E. coli virulence factors in feces of animals supplemented with phytogenics were numerically lower than those fed the control treatment (8.5 vs 8.9 log10/g fae gene, P=0.32; 6.8 vs 7.2 log10/g est-II gene, P=0.50). Results suggest that the phytogenics used in this experiment is beneficial during post-weaning diarrhea outbreaks by improving performance and livability and by reducing the cost associated with medical treatments in weaned pigs
PSVIII-7 Effects of Bacillus subtilis on colon digesta metabolomic profiles in weanling pigs experimentally infected with a pathogenic E. coli
Authors: Kim Kwangwook , Liu Yanhong
Published: November 2020

Our previous studies have shown that supplementation of Bacillus subtilis enhanced growth rate, improved gut barrier function, and modified colon microbiome of weaned pigs infected with pathogenic Escherichia coli (E. coli). The objective of this experiment was to investigate the effects of Bacillus subtilis on colon digesta metabolomic profiles of weaned pigs experimentally infected with F18 E. coli. Forty-eight pigs (6.73 ± 0.77 kg BW) were individually housed in disease containment rooms and randomly allotted to one of the four treatments (12 pigs/treatment). Four treatments included negative control (NC), positive control (PC), low-dose (1.28 × 109 CFU Bacillus subtilis/kg feed), and high-dose (2.56 × 109 CFU Bacillus subtilis/kg feed). The experiment lasted 18 d [7 d before and 11 d after first inoculation (d 0)]. The F18 E. coli inoculum was orally provided to all pigs with the dose of 1010 cfu/3 mL for 3 consecutive days, except NC. Twenty-four pigs (6 pigs/treatment) were euthanized on d 5 post-inoculation (PI) and the remained pigs were euthanized on d 11 PI to collect colon digesta for the analysis of metabolomic profiles by gas chromatography time of flight-mass spectrometer (GCTOF-MS). All processed data were statistically analyzed and evaluated by online MetaboAnalyst tool. No significant differences were observed in the metabolites between NC and PC on d 5 and 11 PI. Compared with PC, low- and high-dose Bacillus subtilis reduced (Fold change > 1.5; FDR < 0.20) four metabolites (proline, 2-hydroxyglutaric acid, lysine, and glutamic acid) and two metabolites (ribose, and D-xylulose) in colon digesta on d 5 PI, respectively. These metabolites were related to aminoacyl-tRNA-biosynthesis, arginine and proline metabolism, and lysine degradation. In conclusion, supplementation of Bacillus subtilis modified the levels of microbial metabolites associated with amino acid metabolism in colon digesta of pigs.
PSVIII-1 Determination of in vitro DM, N and NDF digestibility and fermentability in novel corn co-products for swine
Authors: Palowski Amanda , Yang Zhaohui , Urriola Pedro E , Shurson Gerald C
Published: November 2020

New process technologies are being implemented in the ethanol industry resulting in new high protein corn co-products (HPCP) containing more gross energy and amino acids than conventional distillers dried grains with solubles (DDGS). Thus, estimates of nutrient digestibility for HPCP are needed to assess potential feeding value for swine. Furthermore, yellow dent corn is the predominant grain source in U.S. ethanol and co-product production whereas flint corn is used in Brazil. This study determined and compared in vitro dry matter (DM), nitrogen (N), and neutral detergent fiber (NDF) digestibility and fermentability of U.S. and Brazil corn DDGS and new HPCP. In vitro methods evaluated DM, N, and NDF digestibility and fermentability of 2 corn DDGS samples from U.S. (POET and ICM), 2 DDGS samples from Brazil (BR1 and BR2), 1 corn fiber and solubles sample (CF+S), 3 high protein distillers grains (HP-DDG) samples (BR-HP, US-HP, US-HPG1.5), and 2 HP-DDG samples containing high yeast (Ultramax; UM) and StillPro (SP). Digestibility of DM from hydrolysis varied and was greatest for UM (87.13%; P < 0.001) compared with all other co-products. Fermentability of DM was greater (P < 0.001), and similar for UM (85.6%), SP (76.8%), and US-HP-DDG (72.8%) compared with other co-products. Digestibility of N was greater for UM (91.2%; P < 0.001) compared with all other co-products. NDF digestibility was greater (P < 0.001) for UM (62.5%) and SP (60.5%) compared with all other co-products. POET and ICM DDGS had greater (P < 0.001) DM hydrolysis (78.7% and 68.2%, respectively), than BR1 (37.2%) and BR2 (35.0%) and N digestibility (POET = 65.0%; ICM = 58.9%) compared with BR1 (54.4%) and BR2 (43.4%). These results suggest greater nutritional value for Ultramax and StillPro than conventional DDGS and HP-DDG sources (U.S. and Brazilian) due to greater DM, N, and NDF digestibility.
PSVIII-11 Effects of feeding diets containing corn distiller’s dried grains with solubles (DDGS) on growth performance in broilers: a meta-analysis
Authors: Jang Jae-Cheol , Zeng Zhikai , Urriola Pedro E , Shurson Gerald C
Published: November 2020

Published studies involving different feeding strategies and diet inclusion rates of corn distillers dried grains with solubles (cDDGS) for broilers have resulted in variable growth performance responses. Therefore, a meta-analysis was conducted to quantitatively summarize the impact of feeding diets containing cDDGS on growth performance of broilers using a total of 16 publications with 56 observations in the database. The mean difference (MD) of BWG, FI, and G/F ratio were expressed as percentage between feeding corn-soybean meal-based (CSB) diet and addition of cDDGS into CSB diet of broilers. Individual observations were analyzed using a multivariable model (Proc GLIMMIX, SAS) to evaluate growth performance responses based on feeding phase, inclusion level of cDDGS, and oil content of cDDGS as a fixed effect. Broilers fed cDDGS diet had decreased BWG (-0.1 %, P < 0.01) and increased FI (0.3 %, P < 0.01) compared with broilers fed CSB diet. Moreover, every percentage unit increase in the inclusion level of cDDGS in CSB diet was associated with a decrease in BWG (0.30 %, P < 0.01) and FI (2.64 %, P < 0.01). The MD of BWG was greater for broilers fed cDDGS in the starter (4.70 %, P < 0.01) and entire (3.00 %, P < 0.01) period compared with the finisher feeding period. However, entire feeding period showed greater MD of G/F ratio (2.11 %, P < 0.01) compared with starter and finisher periods. The MD of BWG (-1.02 %, P < 0.01) and FI (-2.48%, P < 0.01) were decreased for broilers fed more than 20 % in the diet. In conclusion, including more than 20 % cDDGS into the broiler diet decreased BWG and FI. The recommended inclusion level of cDDGS into the broiler diet is 10 to 20 % during the entire period.
PSVII-16 Effects of genetic selection for early puberty on the hypothalamic-pituitary-ovarian axis in gilts
Authors: Harlow KaLynn , Renwick Allison , Shuping Sydney , Sommer Jeff , Knauer Mark , Nestor Casey
Published: November 2020

Puberty onset in gilts is an awakening of the hypothalamic-pituitary-ovarian axis that is the result of reduced estradiol-negative feedback at the level of the hypothalamus which yields elevated gonadotropin secretion from the anterior pituitary. Given the importance of hypothalamic kisspeptin and neurokinin B (NKB) signaling for the onset of puberty in other species, the objective of this study was to determine if gilts selected for early pubertal onset (SELECT) would display measurable differences within the hypothalamus (i.e. increased expression of kisspeptin and NKB) and within the ovary (i.e. increased ovarian mass) compared to age-matched and weight-matched gilts (CONTROL) that achieve puberty 20 days later than SELECT gilts. Gilts were sacrificed at three timepoints: Timepoint A, both groups were determined to be prepubertal (n=6/group), Timepoint B, SELECT gilts were determined to be pubertal and CONTROL gilts were determined to be prepubertal (n=6/group), and Timepoint C, both groups were determined to be pubertal (n=6/group). All animals were euthanized, heads were perfused with 8 L of 4% paraformaldehyde, and ovaries were harvested. Brain tissue was removed post-fixation, submerged in fixative for 24 hrs followed by 20% sucrose until sectioned for immunohistochemistry. Ovarian mass tended (p≤0.10) to be greater for SELECT gilts on the right ovary (4.34 vs. 3.67 g) and the left ovary (4.49 vs. 3.68 g) when compared to CONTROL (Timepoints A and C), and at Timepoint B right ovary mass from SELECT gilts was heavier than CONTROL gilts (p< 0.05; 7.22 vs. 4.65 g). Hypothalamic immunohistochemistry for kisspeptin and NKB revealed differences in neuronal fiber density between both groups at various timepoints. Therefore, we conclude that gilts genetically selected for early puberty do so via changes within the hypothalamus that increase gonadotropin secretion and, in turn, stimulate ovarian growth to ultimately advance the timing of puberty onset.
PSVII-22 Trichostatin A as an aging agent in an oocyte
Authors: Arena Haley A , Hicks Emma C , Whitaker Brian
Published: November 2020

As oocytes experience prolonged aging, reactive oxygen species (ROS) typically accumulate, the mitochondrial electrochemical potential gradient dissipates, and cumulus cells undergo expansion. Trichostatin A (TSA), used to stimulate aging, delays oocyte maturation by inhibiting germinal vesicle breakdown during meiosis. The objective of this study was to study the effects of aging during in vitro oocyte maturation in pigs. Oocytes (n=881) were matured with or without TSA (100 ng/mL) for 24 or 48 h followed by an additional 16 h of maturation without TSA. At the end of maturation, oocytes (n=446) were evaluated for cumulus cell expansion (CCE). A portion of the oocytes were stained to determine the relative levels of ROS (n=476) or mitochondrial electrochemical potential gradient dissipation (n=405). Fluorescent images of the oocytes were acquired, images were analyzed using ImageJ, and statistical analysis of the data was performed using ANOVA and Tukey’s test. Oocytes matured with or without TSA for 48 h had significantly less (P < 0.05) CCE compared to oocytes matured without TSA for 24 h. Oocytes matured without TSA for 24 h generated significantly different (P < 0.05) levels of ROS compared to oocytes matured with TSA for 48 h. Oocytes matured without TSA for 48 h had significantly higher (P < 0.05) mitochondrial membrane potential compared to the all other treatments. Results indicate that oocytes experiencing prolonged aging have less CCE and a decrease in mitochondrial membrane potential but no consistent or predictable trends in ROS formation. The use of TSA to stimulate aging in pig oocytes remains a valid and a reliable option.
PSVIII-21 Parasite prevalence and fecal egg counts on organic pig farms
Authors: Li Yuzhi , Hernandez Alexander , Carr Rick , Dukes Shelby , Lou Maria , DeWitte Diane
Published: November 2020

Swine parasites present challenges for organic pig farmers and represent suboptimal animal health because the use of synthetic anthelmintics is not allowed. The objective of this study was to investigate prevalence and fecal egg counts (FEC) of three intestinal parasites (Ascaris, Trichuris, and Oesophagostomum) on organic pig farms in the United States. Nine farms across 4 states were investigated. Pigs on all farms were raised within no-confinement facilities, had access to the outdoors or pasture except for one farm that housed sows in a hoop barn, and no use of synthetic anthelmintics from birth to market weight for growing/finishing pigs and from the third trimester of gestation for sows. Herd size varied from 12 to 416 (median=50) pigs. Four to 16 fecal samples were collected in each pen or pasture. A total of 186 samples were analyzed for FEC using the concentrated McMaster technique to yield eggs per gram (epg) of fecal samples. Pigs were categorized as breeders (gestating sows of all parity and boars), growing pigs (2 to 5 months old), or finishing pigs (5 months old to market weight). Results indicate that 56%, 89%, and 44% farms were infected with Oesophagostomum, Ascaris, and Trichuris, respectively. Overall, breeders on infected farms had higher (P=0.01) FEC of Oesophagostomum (1,115 epg ± 1,647 SD) than growing (60 epg ± 9.5 SD) and finishing pigs (237 epg ± 234 SD). Growing and finishing pigs had higher (P< 0.001) FEC of Ascaris (1,733 epg ± 1,208 SD for growing pigs; 1,162 epg ± 630 SD for finishing pigs) than breeders (5 epg ± 2.5 SD). Trichuris FEC was relatively low (< 80 epg for pigs in all production stages) compared to other parasites. Results suggest that swine parasite infection is common on organic/alternative farms and strategies to control parasites need to be developed.
PSI-1 Effects of choline on immune cell function in growing cattle supplemented with guanidinoacetic acid and creatine
Authors: Aufdemberge Hope D , Grant Madeline S , Bradford Barry J , Mamedova Laman K , Titgemeyer Evan C
Published: November 2020

Methyl sources that affect immune function/inflammation potentially have value in the beef industry, notably with receiving cattle. In newly received beef cattle, an active immune response with appropriately controlled inflammation is critical to optimize both biological and economic efficiency, due to the high cost of disease and its treatment. Our objective was to determine how modulation of methyl group status would affect polymorphonuclear cell (PMN; primarily neutrophils) function. Six ruminally cannulated Holstein steers (200 kg) were used in a 6×6 Latin square design with 10-d periods. Factorial treatments included 3 methyl group modulators (MGM: control; 15 g/d guanidinoacetic acid, which consumes methyl groups; or 16.8 g/d creatine, which spares methyl groups) and 2 levels of choline (0 or 5 g/d). Steers received 4 kg/d of a corn-based diet. Treatments were continuously infused abomasally. On d 10 of each period, jugular blood was collected, and PMN were isolated. Cells were challenged with or without LPS (1 μg/mL) for 30 min followed by addition of dihydrorhodamine (100 μM) for 10 min and E. coli covalently labeled with Texas Red at a ratio of 20:1 for an additional 40 min. PMN activity (phagocytosis and oxidative burst) was assessed using a capillary ﬂow cytometer. Oxidative burst, with or without LPS challenge, was not affected by choline (P >0.42) or MGM (P >0.75). Phagocytosis without LPS was not affected by choline (P=0.29) or MGM (P=0.30). When PMN were challenged with LPS, phagocytosis tended to be reduced by choline (P=0.09) but was not affected by MGM (P=0.35). Choline tended to reduce phagocytosis by PMN challenged with LPS, suggesting that it may reduce inflammatory responses. A more robust understanding of methyl group metabolism may allow nutritionists to supply these nutrients to optimize immune function.