bluuebunny/crossref_metadata_2025 huggingface dataset:
340 Relationship of Retained Energy in Lactating Beef Cows to Maintenance Energy Requirement and voluntary Feed Intake
Authors: Briggs Emma A , Anderson Claire , Holder Amanda , Gross Megan A , Lalman David
Published: October 2021

This study’s objective was to determine the relationship between retained energy, lactation maintenance energy requirement (MER), and dry period voluntary feed intake (VOL) in beef cows. Twenty-four mature fall-calving Angus cows were used in an 82-d study during lactation to establish maintenance energy requirements followed by a voluntary feed intake study after weaning. During the lactation MER experiment, cows were housed in 2 drylot pens and limit-fed a mixed hay/concentrate diet (17.8% CP, 2.6 Mcal/kg ME, DM basis) individually once per d in a stall barn. Cows were adapted to the diet and feeding management for the first 16 d. Subsequently, cows were weighed and feed allowance adjusted at 14-d intervals to achieve BW and BCS stasis. Milk yield and composition were determined on d – 10, 49, and 77 using a milking machine. Retained energy was calculated as average daily maternal tissue energy change plus average daily milk energy yield. During the post-weaning VOL experiment, cows were provided ad libitum access to a grass hay diet for 41 d (8.15% CP, 1.8 Mcal/kg ME, DM basis) using five individual feed intake monitoring units (SmartFeed, C-Lock, Inc). Each one unit increase in metabolizable energy intake, kcal/kg BW0.75 was associated with a 0.86 ± 0.28 kcal/kg BW0.75 increase in total retained energy (P = 0.005). Using this partial efficiency coefficient, ME required for maintenance declined by 0.80 ± 0.11 kcal ME/kg BW0.75 for each additional kcal net energy retained/kg BW0.75 (P < 0.0001). There was no relationship between lactation-period retained energy and post-weaning VOL forage dry matter intake. The present study results contradict previous reports suggesting that maintenance requirements increase with increasing productivity.
351 Awardee Talk: Advances in Animal Nutrition Research
Authors: Harmon David L
Published: October 2021

The major focus of animal nutrition studies is the efficient production of meat, milk, and eggs. Much has changed in animal nutrition over the past forty years that have facilitated these improvements in efficiencies. While advances in technologies have been quantum and research methodologies have improved yet there remains a need for traditional methodologies. Feed intake, growth rate, and feed efficiency still define success. Nutrient balance and digestibility studies, which originated in the 1800s, provide much-needed information regarding the value of feedstuffs. Bioassays are still needed to ascertain the requirements of each nutrient as these are ever-changing because animals are ever-changing. Genetic improvement dictates that requirements be continually reassessed and refined. Technologies that impact animal production, e.g. growth promotants, ionophores, repartitioning agents, hormones, nutraceuticals, etc. may all impact these requirements and should be considered. The challenge for the next generation of researchers will be to interface the technologies, genomic tools, and traditional approaches to provide targeted nutritional strategies tailored for individual genetic potential. Researchers must have a broader grasp of all the available tools if we ever hope to fully implement technologies and interface these with new knowledge to provide optimal nutrition. Changes in consumer preferences will continue to provide new challenges that must be met by research from a continually decreasing pool of researchers. This too will necessitate broader skill sets and increased multi-disciplinary support. The next 40 years will bring even greater changes and challenges. Animal agriculture must continue to improve. A goal of increased efficiency will not be enough. We must improve on every aspect of health, well-being, and perception. Nutrition research will be a component of these improvements but improving technologies will permit the evaluation of much more. Consumers will demand an optimum existence be demonstrated for each animal.
354 Awardee Talk: Midwest Cattle Feeding Over the Past 40 Years
Authors: Loy Daniel D
Published: October 2021

The success of a cattle feeding region is dependent on many factors including resources and technology. Forty years ago, the once-dominant Midwest region had lost its competitive advantage in both areas. Today this industry has reinvented itself. This presentation reviews this journey and looks forward to new opportunities. There have been at least two disruptive technologies that affected cattle feeding, especially in this region over this time. The first is the convergence of microcomputer technology with the development of growth models based on the California Net Energy System. Decisions based on this new knowledge had a profound impact on feed conversion, growth and management. The second disruptive technology was the development of the ethanol industry and widespread availability of corn coproducts, especially high moisture corn coproducts. This development brought large quantities of a very high-quality feedstuff and inclusions in beef finishing diets became standard. Considerable research and education were needed to develop cost effective feeding programs with this new opportunity. Other changes have occurred across the cattle feeding industry over this time. Cattle size and carcass weights have continued a linear increase. Carcass quality and marbling has increased due to genetic selection, feeding endpoints and other factors. Improved growth technologies have continued to be developed and evaluated. Nutritional requirements of cattle for some nutrients have been fine-tuned but more work is needed. Disruptive technologies in the future may involve the convergence of precision livestock technology, smart sensors, artificial intelligence. Engineering developments and energy costs will affect the future of feed processing and delivery. Regardless of future technologies successful cattle feeding in the future will require access to feed resources, excellent nutrition and health management and strategies to manage risk.
367 Determination of Circulating Interleukin 13 in Sheep After Infection with Haemonchus Contortus
Authors: Patton Curtis , Greiner Scott P , Bowdridge Scott A
Published: October 2021

Interleukin 13 (IL-13) is a critical cytokine involved in development of Type 2 (Th2) immunity, necessary for generating full host protective response against Haemonchus contortus (Hc). St. Croix (STC) sheep have well-documented resistance, generating a robust immune response to larval stages of infection, thus preventing establishment of adults due to a rapid cellular and strong TH2 immune response. Previous studies have shown that exposing Hc L3 to recombinant-IL-13 causes a significant reduction in larval speed and distance traveled. These data, coupled with known physiological effects of IL-13 on increased gut motility, indicate that oral administration of IL-13 may have potential therapeutic benefits. Therefore, the aim of this study was to evaluate the amount of IL-13 in circulation in both STC and Suffolk (SUF) sheep to establish a proper dosage for oral administration as a therapeutic control for parasitic infections. Two contemporary groups STC (n = 14) and SUF (n = 14) were raised in an Hc-free barn for the duration of the project. Four weeks after weaning each lamb received a single oral dose of 10,000 Hc-L3. Infection persisted for 5 weeks before animals were dewormed with levamisole, and then rested for three weeks. After which, primed lambs were challenged with an additional 10,000 Hc-L3. Blood was collected daily for 14 days. Serum was removed and pooled (by breed/by day) and concentration of IL-13 was detected using an ovine specific IL-13 ELISA assay. There was a difference in the mean amount of circulating antibody between breeds STC (4.415) SUF (4.093) (P < 0.001). STC have a higher amount of circulating IL-13 and that amount may be utilized in development of future therapeutic treatments.
517 Late-Breaking: Influence of Pre-heat Treatment on the Formation of Heterocyclic Aromatic Amines in Grilled Pork
Authors: Utyanov Dmitry A , Semenova Anastasia , Kulikovskii Andrey V , Knyazeva Alexandra S , Revuckaya Nataliya
Published: October 2021

Pork steaks (m. Longissimus dorsi) with a thickness of 15±5 mm were prepared for the experiment. Ready-made mixtures intended for catering were used during the preparation of samples for marinating steaks: - marinade containing a mixture of vegetable oils, salt, paprika, garlic, onion and black pepper (sample 1); - marinade, which contains water, salt, paprika, black pepper, red pepper, garlic, coriander and mustard (sample 2); and mixtures for dry marinating:- mixture with red pepper (salt, red pepper) (sample 3);- mixture with paprika (salt, paprika) (sample 4). Salting and pickling were carried out at a temperature of 4±2°C for 24 hours. Thereafter, the steaks were grilled at 230°C for 10 minutes using electric grill, and the steaks were turned over once during the cooking process. Steaks that were not pickled and salted were taken as a control sample. Samples were tested for the presence of MeIQx and PhIP. The analysis was performed using an Agilent 1200 HPLC system (USA) with an Agilent 6410B three quadrupole mass spectrometer (Fragmentor voltage 130 V, Dissociation energy 30 V, molecular ions 214.6 and 225.6 m/z, daughter ions 199.5 and 210.5 m/z for MeIQx and PhIP respectively). The studies were carried out in two selections with 3 parallel measurements in each. The arithmetic mean of three parallels in the first selection was taken as the final result, provided that the Student’s t-distribution of two samples for each analyte to be determined in each sample did not exceed the tabular value at n=3 and the confidence level p=0.95, i.e., the differences between the samples are not statistically significant. Studies have shown that long-term preliminary processing of meat by marinating and salting led to both a decrease and an increase in the content of HAA in fried steaks. The results of studies of HAA content in the control and experimental samples are shown in the Table.
508 Late-Breaking: Heritability and Validation of Sow Uterine Prolapse in the United States
Authors: Stevens Tomas , Dunkelberger Jenelle , Knol Egbert
Published: October 2021

Uterine prolapse impacts animal welfare and reduces sow farm profitability. In general, the incidence of uterine prolapse is higher in the United States than in other countries. Some suspected causes of uterine prolapse include water quality, vitamin deficiency, mycotoxins, and genetics. The objectives of this study were to: 1.) estimate the heritability of uterine prolapse; and 2.) to validate estimated breeding values (EBVs) for uterine prolapse in an independent, related population. Prolapse records collected from purebred females at a commercial multiplier (n = 16,434) and nucleus farm (n = 4,096) were used for training and validation, respectively. Phenotypes were recorded as the presence/absence of uterine prolapse at the sow level. Heritability estimates were derived from the training dataset by fitting year-season of insemination and parity at removal of the sow as fixed effects and animal as a random effect. Using the same model, validation was performed by regressing corrected offspring performance on sire EBV in the validation dataset. A pedigree- and a genomics-based relationship matrix were used for parameter estimation and the validation analysis, respectively. Incidence of uterine prolapse was heritable at 0.15 ± 0.02 and 0.22 ± 0.02 when analyzed using a linear vs. threshold model, respectively. Regression of corrected offspring performance on sire EBV resulted in a slope parameter of 0.40 (95%-CI; 0.27 - 0.54, including the expected value of 0.5), indicating that sire EBV is predictive of uterine prolapse among his offspring. In conclusion, these results show that uterine prolapse is lowly-to-moderately heritable, and therefore, mainly due to environmental factors. Higher incidence of uterine prolapse within the United States vs. other geographic locations confirms the existence of a strong environmental component. Genetic selection can be used to address genetic factors, but identifying/mitigating environmental triggers remains critical to reducing the incidence of uterine prolapse within the U.S. swine industry.
478 Dietary Butyrate and Valerate Glycerides: Effects on Growth and Systemic Immunity of Weanling Piglets Coinfected with F4 and F18 Escherichia coli
Authors: Kovanda Lauren L , Park Jungjae , He Yijie , Park Sangwoo , Wu Ruochen , Wong Braden , Kim Kwangwook , Liu Yanhong
Published: October 2021

Enterotoxigenic Escherichia coli (ETEC) F4 and F18 are the two most dominant pathogenic strains in weaned pigs. The objective of this experiment was to test the effects of dietary monobutyrin and monovalerin on performance and systemic immunity of weanling piglets coinfected with F4/F18 ETEC. Twenty weaned pigs (8.21 ± 1.23 kg) were individually housed and were randomly allotted to one of three diets: control (n = 6), 0.1% monobutyrin (n = 7), or 0.1% monovalerin (n = 7). The experiment was conducted 14 days, including 7 days’ adaption and 7 days post-inoculation (PI). On d 0, d 1, and d 2 PI, pigs were inoculated with 0.5 × 109 CFU/1.5 mL each of F4 and F18 ETEC for three consecutive days. Diarrhea score was recorded daily to determine frequency of diarrhea. Piglets and feeders were weighed throughout the trial to analyze growth performance. Fecal cultures from pigs on d 0, 2, and 4 PI were inspected to identify the absence or presence of hemolytic coliforms. Blood was collected on d 0, 4, and 7 PI for complete blood cells count. All data were analyzed by the Proc Mixed of SAS with randomized complete block design. Pigs supplemented with monovalerin and monobutyrin had numerically higher ADG (249 and 282 g/day) from d 0 to d 7 PI than pigs in control (198 g/day). Supplementation of monovalerin reduced (P < 0.05) frequency of diarrhea throughout the experiment. Pigs fed monovalerin had lower (P < 0.05) neutrophil counts on d 4 PI compared with control. Hemolytic coliforms were observed in all fecal cultures from d 2 and d 4 PI, confirming fecal shedding of ETEC. Results of this study indicate the potential benefits of monovalerin supplementation on performance and disease resistance of weaned pigs coinfected with F4 and F8 ETEC.
481 Current Knowledge Gaps in Swine Production Management
Authors: DeDecker Ashley
Published: October 2021

Recently I’ve started questioning everything I thought I knew about common management practices in the swine industry. As a scientist I’m trained to trust the science and use the data, but when the science contradicts common knowledge, do I question the science or question the common knowledge? Perhaps both, which has led me down a path to scientifically reevaluate the basic management principles of hog production; or taking it back to the basics. Management practices that were implemented 30 years ago are still being commonly used; however, over the years those practices have been altered to make them simpler or cheaper. By altering these fundamental principles, we may have unintentionally disrupted the overall intent of the principle and caused accidental consequences to production. For example, it is common knowledge that newborn pigs need to be dried at birth to improve the chance of survival. Originally these pigs were picked up and thoroughly dried and rubbed to stimulate the muscles and then strategically placed at the teat and encouraged to suckle. Over the years this practice has been altered; sprinkling drying agent over the litter instead of picking them up and using cheaper drying agents that may not be intended for this purpose, and placing the pigs down at the back of the crate. Robust and replicated science is needed to identify which components of these fundamental management processes are beneficial, serve a purpose, and therefore should not be adulterated. Therefore, prioritizing research back to the basics of fundamental management practices.
482 Awardee Talk: Challenges and Opportunities Facing Mineral Nutrition in the Next Decade
Authors: Patience John
Published: October 2021

The science associated with mineral nutrition is evolving at an accelerated pace. Some topics of investigation have persisted for decades; typical examples include clarification of mineral requirements, evaluation of mineral sources, definition of mineral bioavailability and physiological and metabolic interactions among minerals, to name a few. The fact that these topics have endured for so long serves to illustrate their importance to our craft, as well as the increasing sophistication of the science available to delve more deeply into our understanding of mineral nutrition. Newer topics that involve minerals directly and/or indirectly are attracting increasing attention – and for good reason. As one example, there is a growing body of data pointing to oxidative stress as a relevant issue in modern pork production. As another, the interaction of minerals with fiber has received considerable interest in the past, but recently, the topic has been further elevated by health and environmental concerns. While the above might be considered typical classical nutrition topics, mineral nutrition can also be viewed in a more holistic manner. To what extent is mineral nutrition involved in the observed increase in sow mortality in the past decade? How can and should mineral nutrition be included in precision feeding programs? What further roles of mineral nutrition might be involved in environmental sustainability? Where do we stand on the involvement of mineral nutrition in acid-base balance and does it have greater value in production today than previously considered? This presentation will consider current examples of how mineral nutrition impacts applied swine nutrition as well as overall pork production.
494 Walk the Talk – Teaching Is Still Teaching – Just Expanding Your Tool Box
Authors: Herring Andy D
Published: October 2021

Beef Cattle Production & Management (ANSC 406) is a Texas A&M University “Communications” course and an elective in the undergraduate Animal Science curriculum. This course (3 hr lecture, 2 hr lab) is taught in Fall, Spring, and Summer semesters. The author has taught this (or equivalent) course since 1995, and various teaching technologies have incrementally crept into the course. Prior to COVID-19 restrictions, the class was taught traditionally through in-person lecture and lab meetings, with in-class, closed-note exams, and supported with online resources. Students are assigned to groups of 4 or 5 for semester-long work on a ranch management project with peer review comprising 20% of the grade. This report summarizes student exam grades and ranch project peer evaluations through semesters Fall 2019 to Fall 2020 where the class format was (1) traditional face-to-face (TF2F), (2) initially TF2F then switched abruptly to 100% remote/online, (3) 100% remote/online for the entire semester, and (4) a blended/hybrid format, respectively. Semester-to-semester exam grades and group member peer evaluations were compared through mixed model analyses of variance. There were no differences in exam grades (P > 0.10) across these semesters with the exception of Exam 3 that deviated 3.7% (P = 0.020) from lowest to highest mean scores. Relative exam grade variability (based on CV and range) remained almost constant from closed-book to open-note format. Remote vs. F2F status did not influence (P > 0.05) group peer evaluation scores regarding Q1: “Overall level of participation” or Q4: “Willingness to work for success of your group” when group number or student were included in statistical models. Model R-square values for Q1/Q4 increased from 0.037/0.050 to 0.161/0.171, and 0.424/0.457 when group, and student were added, respectively. Individual student perceptions and experiences appear to be major drivers of learning outcomes no matter the course delivery style.
PSXVI-17 Estimation of inbreeding in local sheep breeds of west Asian and central Asian origin based on high-density SNP-genotypes
Authors: Deniskova Tatiana E , Abdelmanova Alexandra S , Dotsev Arsen V , Lushihina Eugenia , Zhunushev Asankadyr , Reyer Henry , Selionova Marina I , Wimmers Klaus , Brem Gottfried , Zinovieva Natalia A
Published: October 2021

Maintaining high levels of genetic diversity is a key factor of successful breeding of resilient, resistant to diseases and productive sheep. Prevention of inbreeding is of special importance in the mountainous hard-to-get habitats where gene flow is limited or absent. An assessment of inbreeding coefficients based only on pedigree information is not always correct. In addition, pedigree information is often missing for flocks of native sheep. In this regard, we performed a genomic assessment of inbreeding in 15 local sheep breeds inhabiting severe environments of Russia and neighboring Asian countries based on estimations of standardized multilocus heterozygosity (sMLH) and runs of homozygosity [F(ROH)]. For this study, we used SNP genotypes of twelve Russian local breeds (n = 316) and three Kyrgyz local breeds (n = 68), which were generated using Ovine Infinium® HD SNP BeadChip (Illumina, CA, USA). The sMLH values were calculated using R package inbreedR and visualized in R package ggplot2. The F(ROH) values were calculated using the R package detectRUNS by applying the consecutive runs method. Mean sMLH values were varied from 0.962 ± 0.006 in the Andean breed to 1.031 ± 0.002 in the Buryat breed and averaged to 1.001± 0.004. The least mean F(ROH) value was detected in the Mongolian breed (0.0043 ± 0.0009) while the greatest ones were observed in the Alai and Andean breeds (0.0364 ± 0.0049 and 0.0357 ± 0.0061, respectively). The strong negative correlations between sMLH and F(ROH) were detected for all of studied breeds (r2 = –0.8496, CI = –0.8752… –0.8192). The obtained data is relevant for control of inbreeding level in the populations and for future sustainable management of native fat-tailed sheep breeds. The study was funded by RSF No. 19-16-00070.
PSXVI-21 The effect of enhancing the thermal environment of piglets on physiology, behavior and productivity
Authors: Lay Donald C , Enneking Stacey A , Morello Gabriella M
Published: October 2021

To determine if increasing the heated area provided to piglets may improve their welfare; Sows (n = 27) were assigned to stalls using a traditional heat lamp (Control), or stalls using 2, 0.4 x 2.4 m heated mats (Heat). The mat temperature was maintained at approximately 39 °C until the 3rd d post-farrowing when they were replaced with a traditional heat lamp. At 1 d of age, piglets’ temperature was recorded, and blood samples were taken from 4 piglets per litter to measure cortisol, lactate, and glucose. Of these piglets, 2 were females and 2 males, 1 each weighing above average (thrifty) and 1 each below average (unthrifty). ADG of all piglets and mortality were recorded on d 3, when the heated mats were replaced with heat lamps, as well as at weaning. There were no treatment differences (P > 0.10) for cortisol (4.52 ± 0.22 ug/dL), glucose (102.84 ± 2.11 mg/dL), or lactate (2.42 ± 94.77 mmol/L). Unthrifty piglets had greater cortisol concentrations (5.45 ± 0.34 vs. 3.64 ± 0.24 ug/dL, P < 0.0001) and lower glucose (97.3 ± 3.06 vs. 108.37 ± 2.76 mg/dL; P < 0.0014) than thrifty. ADG was not different (P > 0.10) on d 3 (0.12 ± 0.01 kg) or at weaning (0.24 ± 0.003 kg). There was no difference in body temperature between treatments (39.23 ± 0.03 °F, P > 0.10). Day 3 mortality was lower in Heat crates than Control (0.04 ± 0.02 vs. 0.12 ± 0.03, P < 0.02); however, mortality at weaning did not differ (11 ± 0.02%, P > 0.10). In conclusion, increasing the warm area in farrowing crates with heated mats over the length of the piglet area may increase survivability while provided.
PSI-B-25 Assessment of the genetic resources of Russian local cattle breeds by genome-wide SNP analysis
Authors: Abdelmanova Alexandra S , Dotsev Arsen V , Sermyagin Alexander A , Brem Gottfried , Zinovieva Natalia A
Published: October 2021

Russia is reach by local cattle genetic resources, which are well adapted to the different environment. However, the modern cattle husbandry tends to the replacing the local cattle breeds by highly productive commercial breeds, which can lead to the decline of genetic diversity. The aim of our work was to estimate the genetic identity of five Russian local cattle breeds, including Yaroslavl (n = 52), Kholmogor (n = 26), Istoben (n = 21), Tagil (n = 26), and Black-and-White (n = 44). The Holstein breed (n = 49), which is actively used for improvement of above breeds was included in the study for comparison. The genotyping was performed using GGP Bovine 150K Array (Illumina, San Diego, CA, USA) and more than 112000 autosomal SNPs passed through the quality control and were selected for the analysis. We observed the significant excess of heterozygotes in four studied breeds (the values of unbiased inbreeding coefficient were varied from -0.009 to -0.022), except for Black-and-White breed. The effective population size (Ne) for Istoben, Tagil and Kholmogor breeds was declined until present, while Holstein and Black-and-White breeds showed the increase of Ne values starting at 5 generations ago. The Black-and-White breed was the closest to the Holsteins (Fst=0.014), while the Yaroslavl breed was the most distant (Fst=0.115). The highest ratio of Holstein specific genomic components was shown for Tagil (18.79%) and Black-and-White (59.73%) breeds. Our results indicated replacing the part of aboriginal genomic components in several Russian local cattle breeds by Holstein specific components. The comprehensive strategies for conservation of the Russian local cattle breeds are needed to avoid the further decline of genetic diversity of these valuable national animal genetic resources. The study was funded by the Ministry of Science and Higher Education of the Russian Federation within theme 0445-2019-0024.
PSI-B-29 Breeding influence on dairy productivity of Kholmogory cattle
Authors: Nikolaev Semen
Published: October 2021

The Kholmogory breed of cattle is highly adapted to poor feeding and severe climate conditions of the northern part of European Russia, but a lack of dairy productivity also characterizes it. The study aims to measure the productivity of animals obtained by breeding Kholmogory and Holsteins cattle. Purebred Kholmogory (K1, n = 497), first generation` (K1/2×H1/2, n = 387), and second generation` (K1/4×H3/4, n = 384) hybrids were selected for the analysis. Dairy production for 305 days throughout 1st and 3rd lactations and also lifetime productivity were measured. Statistical processing was conducted using Statistica 10 software. The average milk yield of purebred` 1st lactation was 3501±35 kg with a fat content of 3.66±0.01%. The productivity of hybrids in the 1st lactation was higher by 728 kg (P < 0.001) with a fat content of 3.86±0.02% for K1/2×H1/2 and by 1030 kg (P < 0.001) with a fat content of 4.13±0.02 for the K1/4×H3/4 population. In the 3rd lactation, the productivity of K1 was 3948±51 kg of milk with a 3.73±0.02% of fat. This is 941 kg (P < 0.001) and 0.31% (P < 0.001) less than in K1/2×H1/2. During the same lactation in K1/4×H3/4, the average amount of milk was 5508±77 kg with 4.25±0.04% of fat. The maximum lifetime productivity was obtained from K1/2×H1/2. It made 19850±618 kg of milk and 799.6±25.3 kg of milk fat. In the K1 group, 14642±529 kg of milk and 552.6±20.3 kg of fat were obtained per life, and for K1/4×H3/4 14832±590 kg and 620.9±25.6 kg were obtained. The heterosis effect could explain the high lifetime productivity of first-generation hybrids. This is consistent because the average economic use of K1 animals was 3.53±0.11 calving, while for K1/2×H1/2, it was 4.01±0.11. Further breeding with the Holstein led to a significant decrease in the economical use duration to 2.78±0.09 calving in K1/4×H3/4.
PSI-B-27 Association of multiple SNP in the LRP4 gene with features of the cattle elemental status
Authors: Tarasova Ekaterina , Notova Svetlana , Markova Irina , Kataev Vladimir , Plotnikov Andrey
Published: October 2021

Bovine syndactyly is an autosomal monogenic recessive trait associated with multiple mutations in the LRP4 gene encoding low-density lipoprotein receptor-related protein 4. This protein is a specific facilitator of sclerostin-mediated inhibition of both Wnt1/ β-catenin signaling and osteocyte-secreted bone formation. It is assumed that sclerostin induces a decrease in extracellular pH and promotes the release of calcium ions from mineralized substrates. Therefore, mutations in the LRP4 gene might be associated with changes in the elemental status. The aim of this research was to evaluate the elemental composition of serum in cattle carrying multiple SNP in the LRP4 gene (16 trial animals) compared to animals without such mutations (62 control animals). DNA samples from 78 Black Pied cattle were sequenced with a TruSeq Bovine Parentage Sequencing Panel (Illumina, USA) on a MiSeq Illumina platform following by SNP analysis. The elemental composition of the serum was determined using ICP-AES and ICP-MS. The levels of Ca and P, crucial bone elements, were higher in trial cattle than in control group by 12.9% (P = 0.004) and 22.5% (P = 0.008), respectively. The level of V affecting the uniform distribution of calcium salts in bones, was higher in trial group than in control one by 34.5% (P = 0.001). The concentrations of Mn and Mg were higher in trial group than in control one by 23.6% (P = 0.026) and 10.0% (P = 0.044), respectively. The Sr level in trial cattle was higher by 18.8% (P = 0.04) that may indicate the rickets-like state. A similar trend was observed for toxic metals As and Li. This study demonstrates the association of the LRP4 multiple SNP and the changes in cattle elemental status. Moreover, such heterozygous animals have a higher risk of mineral metabolism disorders. This research was supported by The Ministry of Science and Higher Education of the Russian Federation (Project No. 0526-2019-0001).
PSI-B-21 Alternative SNP weighting for multi-step and single-step genomic BLUP in the presence of causative variants
Authors: Santana Bruna , Riser Molly , Fragomeni Breno O
Published: October 2021

This study aimed to evaluate the accuracy of genomic prediction with simulated data, using SNP markers, causal quantitative trait nucleotide (QTN), and the combination of both. The methods used were the best linear unbiased prediction (GBLUP) and single-step GBLUP (ssGBLUP), with alternative SNP weights. Data were simulated using the package AlphasimR. Trait heritability of 0.3 was assumed, and genetic variance was fully accounted for by 100 or 1000 QTNs. A population with an effective size of 200 was selected, and 20 generations were simulated. The genomic information mimicked the 29 bovine chromosomes and included 50k SNP markers evenly distributed across the genome. Approximately 16800 genotypes were available from selected sires and dams in generations 16–19, and 2000 animals in generation 20. Phenotypes for young animals were not included in the analysis, as they were used in the validation. For GBLUP, three pseudo-phenotypes were considered: the raw phenotype, the true breeding value, and the true breeding value with noise added. The genomic relationship matrix was weighted using quadratic weights, calculated based on the SNP variance, and non-linear A, following different equation parameters. The scenario with exclusively causal variants presented accuracies close to 1 for 100 QTL, and slightly lower in the 1000 QTL. For the SNP + QTN scenario, quadratic weights promoted higher accuracy gains than the SNPs alone, especially in the 100 QTN trait. Accuracies converged at higher values for both quadratic and non-linear A weights in the 100 QTN scenario. For the 1000 QTN trait, quadratic weights diverged and reduced accuracy, while non-linear A maintained accuracy at their peaks, depending on the equation parameters. Parameters of non-linear A for highest accuracy were different in each scenario and type of analysis. Proportionally, gains in accuracy were more prominent with GBLUP than with ssGBLUP.
PSVII-27 Genetic analysis of disease resilience of nursery-to-finish pigs under a natural disease challenge model using reaction norms
Authors: Cheng Jian , Lim KyuSang , Putz Austin , Wolc Anna , Harding John , Dyck Michael , Fortin Frederic , Plastow Graham , Dekkers Jack C
Published: October 2021

Disease resilience is the ability of an animal to maintain performance across environments with different disease challenge loads (CL) and can be quantified using random regression reaction norm models that describe phenotype as a function of CL. Objectives of this study were to: 1) develop measures of CL using growth rate and clinical disease phenotypes under a natural disease challenge; 2) evaluate genetic variation in disease resilience. Data used were late nursery and finisher growth rates and clinical disease phenotypes, including medical treatment and mortality rates, and subjective health scores, collected on 50 batches of 60/75 crossbred (LRxY) barrows under a polymicrobial natural disease challenge. All pigs were genotyped using a 650K SNP panel. Different CL were derived from estimates of contemporary group effects and used as environmental covariates in reaction norm analyses of average daily gain (ADG) and treatment rate (TRT). The CL were compared based on model loglikelihoods and estimates of genetic variance, using both linear and cubic spline reaction norm models. Linear reaction norm models fitted the data significantly better than the standard genetic model and the cubic spline models fitted the data significantly better than the linear reaction norm model for most traits. CL based on early finisher ADG provided the best fit for nursery ADG, while CL based on clinical disease phenotypes was best for finisher ADG and TRT. With increasing CL, estimates of heritability for ADG initially decreased and then increased, while estimates of heritability for TRT generally increased with CL. Genetic correlations were low between ADG or TRT at high versus low CL but high for close CLs. Results can be used to select more resilient pigs across different CL levels, or high-performance animals at a given CL level, or a combination of these. Funded by Genome Canada, Genome Alberta, USDA-NIFA, and PigGenCanada.
PSXV-12 What 30 years of accumulated pregnancy data taught us about the Bos indicus influence on reproductive performance of beef cattle
Authors: Martins Thiago , Rocha Cecilia Constantino , Driver Joseph D , Rae Owen , Elzo Mauricio A , Mateesku Raluca , Binelli Mario
Published: October 2021

Bos taurus X Bos indicus crossbreeding is commonly used in tropical and subtropical regions to enhance beef production. The effect of Bos indicus genetics on pregnancy to AI (P/AI) and AI + natural service (P/AI+NS) is understudied. We measured the indicus effect from a 30-year dataset of the University of Florida multibreed herd (MBH; n= 7105 animals). The MBH is composed of six breed groups, according to the following proportion of Brahman: 0–19%, 20–34%, 37% (Brangus), 40–59%, 60%-78% and 79%-100%. Estrus of all animals was synchronized using mainly the SelectSynch+CIDR protocol, followed by three-day AI based on heat or timed-AI (TAI) for non-heat animals. After TAI, animals were bred by NS. Breeding seasons lasted 91±18d. Pregnancy was diagnosed by rectal palpation and/or ultrasonography 30d after AI and 30d after removal of bulls. P/AI was affected negatively (P < 0.001) by the proportion of Brahman, regardless of parity, but P/AI+NS was similar across breeding groups (Table 1). By logistic regression, each 1/32nd increment of Brahman influence reduced odds of P/AI by 0.5% (0/32nd = 51.4% to 32/32nd = 35.3%). The variables of body condition score (BCS), days post-partum (DPP) and body weight at the beginning of synchronization protocol did not explain the negative effect of indicus genetics on P/AI. However, indicus genetics were associated negatively with the proportion of animals AIed in heat (P < 0.001). AI in heat resulted in twice as great (P < 0.001) P/AI (65.4%; n = 984) than no-heat TAI (30.9%; n = 829). In conclusion, indicus genetics did not influence overall pregnancy rates at the end of a 90d breeding season. Nevertheless, indicus influence dampened estrus responses to protocols based solely on GnRH-PGF and progestin/progesterone, resulting on suboptimal P/AI (< 40%).
PSVII-28 Genetic analysis of frame score and performance traits in Nellore cattle–growth, carcass and efficiency traits
Authors: Negreiros Maria Paula , Peripolli Elisa , Magnabosco Claudio U , Guimarães Nayanny , Lôbo Raysildo , Baldi Fernando S , Sainz Roberto D
Published: October 2021

We evaluated a novel frame score system for Nellore cattle raised on pasture (Guimarães et al., 2020 J, Anim. Sci. 98 (Suppl. 4)). Growth traits included age-adjusted weights (kg) at birth (W0), 120 (W120), 210 (W210) and 450 (W450) days of age, and adult weight (AW). Carcass traits (by ultrasound) included ribeye area (REA, cm2), 12th-13th rib backfat (BF, mm), rump fat (RF, mm), and intramuscular fat (IMF, %). Feed efficiency traits included residual feed intake (RFI, kg of DM/d) and DM intake (DMI, kg/d). We applied the previously developed equations (that also include hip height (HH, cm) and age to 12,049 records from the National Association of Breeders and Researchers (ANCP) database:FSmales= -20.35 + 0.1305*REA + 0.2633*BF - 0.5901*RF+ 0.1139*HH + 0.0056*AGEFSfemales = -11.87 + 0.1316*REA - 0.2457*BF - 0.6218*RF + 0.1139*HH + 0.0009507*AGEThe (co)variance components and genetic parameters were estimated using a linear animal model or a threshold animal model depending on the trait. The heritability estimate for frame score was moderate (0.30). Estimated genetic correlations were moderate for growth traits (W0, 0.51; W120, 0.41; W210, 0.35; W450, 0.29; AW, 0.39). Estimated genetic correlations for carcass and efficiency traits ranged from low to high (REA, 0.50; BF, -0.25; RF, -0.84; IMF, -0.15; DMI, 0.29; RFI, 0.10). The estimates support the notion that larger frame animals are heavier, leaner and later maturing, and less feed efficient. The new frame score may be a useful tool for genetic selection of animals that are best suited to their environment.
PSVIII-5 Genetic parameters of thrombin as a proxy for horn fly abundance in beef cattle
Authors: Ling Ashley S , Krause Taylor , Warner Amanda , Duggin Jason , Heins Bradley , Hinkle Nancy , Aggrey Samuel E , Pringle Dean , Rekaya Romdhane
Published: October 2021

Horn flies (Haematobia irritans) are a major nuisance to cattle, especially in warm, humid regions, and are estimated to cause economic losses in excess of $1 billion annually to the U.S. beef cattle industry. Variation in horn fly tolerance has been reported within and across breeds, and heritability estimates ranging between 10 and 80% show a clear genetic basis. However, collecting fly abundance phenotypes is costly and logistically demanding, which precludes large-scale implementation. Consequently, finding correlated phenotypes and endo-phenotypes that are heritable and relatively easy to measure would facilitate implementation of horn fly tolerance genetic improvement programs. Thrombin (TH), a blood coagulation precursor, has a reported association with horn fly count variation within and across cattle breeds. In this study, the genetic basis of thrombin in beef cattle was investigated. Blood samples and horn fly count were collected on 360 cows and heifers twice during the summer of 2019 (June and August). Due to uncertainty associated with assessment of horn fly abundance and thrombin and the fact that economic losses occur only when fly abundance exceeds a certain threshold, thrombin was categorized into 4 classes (1=TH > 500 ng/ml; 2=250< TH< 500 ng/ml; 3=100< TH< 250 ng/ml; and 4=TH< 100 ng/ml). The trait was analyzed using linear (continuous) and threshold (discrete) mixed models. Both models included farm, pregnancy status, and cow age as fixed effects and additive and permanent environment random effects. The pedigree included 642 animals. Estimates of heritability were 0.24 and 0.29 using linear and threshold models, respectively. Estimates of repeatability were slightly higher using the threshold model (0.21 vs 0.19). Despite the small data size, all estimates were non-zero based on their respective highest posterior density intervals. These results indicate reasonable genetic variation for thrombin that could be harnessed for improvement of horn fly tolerance in cattle.
PSXI-5 Genome-wide association study of feed efficiency in Russian Duroc boars
Authors: Belous Anna A , Sermyagin Alexander A , Zinovieva Natalia A
Published: October 2021

The cost of fodder is the major part in expenditure in pork industry. In this regard, improving the feed efficiency is the main goal of breeding programs for the most of pig breeds. Residual feed intake (RFI) is an alternative measure for feed efficiency, which is accepted in different livestock species including pigs. RFI is defined as the difference between the observed and predicted feed intake based on average daily gain and (additionally) back fat thickness. Our aim was to find the candidate genes responsible for RFI in Russian Duroc boars. RFI values for individual boars (n = 766) were calculated using linear regression of daily feed intake on metabolic mid-test weight and average daily gain. The SNP genotyping was carried out using Porcine GGP HD BeadChip (GeneSeek/Neogene). After data quality control, performed in PLINK 1.9, 43,199 SNPs were selected for genome-wide association studies (GWAS). The average daily gain in studied boars was 957 g with variation in individual animals from 424 to 1508 g. Feed conversion rates averaged to 2.21 kg/kg with variation from 1.8 to 3.7 kg/kg. GWAS results showed the presence of 48 SNPs, which were significantly (P < 0.00001) associated with RFI, including 15 SNPs on SSC2, 9 SNP – SSC4, 2 SNPs – SSC6, 21 SNPs – SSC9, and 1 SNP – SSC17. A search for genes located within 0.4 Mb window (0.2 Mb down-stream to 0.2 Mb up-stream from identified SNP) revealed several putative candidates. Functional annotation of the obtained candidates showed the presence of genes involved in protein metabolism (ADAMTS2,UIMC1 on SSC2; NTNG1 on SSC4), regulation of glucose and bile acid metabolism (FGFR4 on SSC2), neuronal development (ENC1 on SSC2; NTRK1, MEF2D on SSC4), vitamin D and K pathways (BGLAP on SSC4). The study was funded by the Russian Ministry of Science and Higher Education No.0445-2019-0029.
PSXII-4 Impact of delayed processing time on total RNA quality and quantitation of transcript abundance
Authors: Wilson Chace , Wege Dias Nicholas W , Pancini Stefania , Mercadante Vitor R G , Biase Fernando
Published: October 2021

Critical biological information related to economically important traits is present in the blood transcriptome in cattle. Following a sample collection, however, RNA molecules containing this valuable information are prone to degradation affecting transcript abundance. Thus, proper sample handling and storage is essential when working with RNA. Here, we hypothesized that delayed time between sample collection and processing would lead to RNA degradation and alter gene transcript quantification. We aimed to determine the effect of delayed processing of whole blood on transcriptomic profiles in peripheral white blood cells (PWBC). We collected blood samples (10ml) in tubes containing anticoagulant (K2EDTA) from estrus synchronized beef heifers (n = 5). The tubes remained chilled on ice until processing time. From each heifer, we collected five samples from the jugular vein. We processed one sample from each animal within one hour of collection, and we delayed the processing time of the remaining samples to three, six, eight, and 24 hours post collection. We extracted total RNA from PWBCs, measured yield and assessed quality. We also quantified transcript abundance of 12,724 genes by RNA-sequencing. Samples processed 24 hours post collection had lower RNA integrity number (RIN) compared to samples processed withing one hour of collection (RIN24h=8.00±0.37, RIN1h=8.52±0.37, P = 0.03). There were four and 504 genes with differential transcript abundance (FDR< 0.05) when comparing eight and 24 hours of delayed processing with samples processed within one hour of collection, respectively. Notably, several genes had >1.4-fold greater transcript abundance when samples were stored on ice for eight or 24 hours. Our results indicate that RNA degradation and cellular activity of PWBCs have critical impact on transcript abundance when blood samples are stored for 24 hours under refrigeration. As the development of RNA-based biomarkers gain importance in cattle production systems, timely handling of samples is critical for accurate results.
PSXV-9 Transgenerational epigenetic variance for production and reproduction traits in maternal-line pigs
Authors: Graham Jason R , Johnson Jay S , Araujo Andre C , Howard Jeremy T , Brito Luiz F
Published: October 2021

Modeling epigenetic factors impacting phenotypic expression of economically important traits has become a hot-topic in the field of animal breeding due to the variability in genetic expression caused by environmental stressors (e.g., heat stress). This variability may be due, in part, to in-utero epigenomic remodeling, which has been reported to be passed from parent to offspring. We aimed to estimate transgenerational epigenetic variance for various production and reproduction traits measured in a maternal-line pig population, using a Bayesian approach. The phenotypes for production [n = 10,862; i.e., weaning weight (WW), birth weight (BW) and ultrasound-backfat thickness (BF)] and reproduction [n = 5,235, i.e., number of piglets born alive (NBA) and total number of piglets born (TB)] traits from a purebred Landrace population were provided by Smithfield Premium Genetics (NC, USA). The pedigree information traced back to 10 generations. Single-trait genetic analyses were performed using mixed models that included additive genetic, common environmental, and epigenetic random effects. The Gibbs sampler algorithm based on Markov chain Monte Carlo was used to estimate the variance components. The epigenetic relationship matrix was constructed using a recursive parameter (λ) related to the transmissibility coefficient of epigenetic markers. A grid search approach was used to define the optimal λ value (λ values ranged from 0.1 to 0.5, with an interval of 0.1). The optimal λ value was determined based on the deviance information criterion, and it was used to estimate the additive and epigenetic variances. For instance, based on preliminary results, the optimal λ value estimated for TB was 0.3 with an additive genetic variance of 0.94 (0.19 PSD) and epigenetic variance of 0.67 (0.18 PSD). The additive genetic heritability was 0.076 (0.015 PSD) and the estimated epigenetic heritability was 0.053 (0.015 PSD). This preliminary result suggests that epigenetics contribute to the non-Mendelian variability in pigs.