bluuebunny/crossref_metadata_2025_split huggingface dataset:
24 Validation of swine enteroids as a model to study Lawsonia intracellularis pathogenesis
Authors: Medida Ramya Lekha , Resende Talita P , Gebhart Connie , Saqui-Salces Milena 
Published: December 2019

Abstract
Lawsonia intracellularis is an obligate intracellular bacterium that causes proliferative ileitis, an enteric disease that costs more than $100 million annually to the US swine industry. Information about L. intracellualris pathogenesis is scarce due to lack of suitable in vitro models to study the infection-induced proliferative changes. L. intracellularis infection of the swine ileum has been shown to decrease the number of mucin-producing goblet cells and increase cell proliferation along with amplification of transient amplifying cells demonstrated by the expression of SOX9. The objective of this study was to validate the use of swine enteroids (three dimensional structures derived from adult intestinal stem cells) as a model to study the intestinal epithelial changes caused by L. intracellularis infection. Swine enteroids plated on transwell plate inserts to cover the surface area were infected with 108 L. intracellularis organisms in culture media per well and incubated at 37⁰C with atmospheric conditions of 8.0% oxygen, 8.8% carbon dioxide, and 83.2% nitrogen. Infected enteroids were collected after 7 days and gene expression levels of mucin 2 (MUC2), enterocyte marker fatty acid binding protein (FABP), endocrine marker chromogranin A (CGA), intestinal epithelium marker villin 1 (VIL1), paneth cell marker lysozyme (LYZ), proliferating cell nuclear antigen (PCNA) and SOX9 were measured. The expression of FABP and LYZ in L. intracellularis infected swine enteroids decreased by 50% and 20% respectively and the expression of SOX9 increased by 50%, with no significant changes for the levels of VIL1 and CGA. The changes observed in the infected swine enteroids reflect the profile of gene expression observed in L. intracellularis infected ileal tissue. Therefore, swine enteroids are a suitable in vitro system to study the dynamics of cell differentiation and proliferation of the intestinal epithelium induced by L. intracellularis infection.
43 Nutritional management for tropical-subtropical-adapted cattle receiving high-concentrate diets
Authors: Rivera Madeline , Adams Jordan , Tedeschi Luis O 
Published: December 2019

Abstract
Contemporary nutritional research investigates the effects of diet formulation and feeding strategies on animal performance and global sustainability under different climates. Functional nutrition models have incorporated the effects of heat stress on net energy for maintenance requirements, dry matter intake (DMI), and milk production when accounting for animal and the environmental factors. It is commonly assumed that growing Bos indicus breeds receiving feedlot-type diets in tropical and subtropical regions have exhibited lower maintenance energy requirements than Bos taurus breeds. However, the ability to predict supplies of energy, protein, and minerals available to meet animal requirements depends on the accuracy and consistency of feed composition values obtained through digestibility trials and chemical analyses. Empirical observations indicate that feedstuffs grown in high temperatures affect cell wall lignification and metabolic activity rates, requiring special procedures for digestion trials. Similarly, physiological adaptation mechanisms in cattle in response to heat stress conditions include evapotranspiration, sweating, and drooling. Heat stress studies have reported a correlation between reduced DMI and increased dry matter digestibility for all breeds of cattle exposed to temperatures that exceed the upper critical temperatures. For that reason, diet formulation with integrated mathematical nutrition modeling can account for nutrient and animal variability, to improve total digestible nutrient values. Furthermore, the water requirement is influenced by stage and type of production, activity, diet composition, feed intake and environmental temperature. Adjustments in management practices could potentially result in reduced production losses caused by thermal heat stress. The utilization of region-specific facilities that accommodate cattle and ensure the availability and quality of drinking water will improve overall animal health and production. Cattle receiving high-concentrate diets in tropical and subtropical regions require adjustments in management and nutrition to mitigate challenges induced by heat stress environments, but improvements are warranted for required energy and water for Bos indicus breeds.
36 Matching cow’s genetics to the environment using genomics
Authors: Decker Jared E , Rowan Troy N , Nilson Sara , Durbin Harly J , Braz Camila U , Schnabel Robert D , Seabury Christopher 
Published: December 2019

Abstract
Cattle poorly adapted to their environment result in lost revenue and jeopardize the stability of the food supply. Genomic data now allows us to rigorously analyze adaptations and avoid the generation of animals that will not thrive. We used selection scans for local adaptation, genotype-by-environment genome-wide association analyses, creation of hair shedding genomic predictions and environmental region-specific genomic predictions of growth traits to characterize and predict local adaptation in beef cattle. Analyzing ~40,000 cattle from three breed associations with ~850,000 high-accuracy imputed SNPs, we used novel selection mapping methods to identify genomic loci responsible for adaptation. We identify 19 different loci (harboring 24 annotated genes) as responding to selection to local adaptation. In cooperation with 74 producers across the United States, over 12,000 cattle were scored on a scale of 1–5 for the early-summer hair shedding phenotype in 2016, 2017, and 2018. Participating cattle were genotyped using the GGP-F250 SNP panel developed by the University of Missouri, which contains ~170,000 candidate functional variants and ~30,000 variants in common with beef cattle industry standard genotyping assays. Genomic breeding values were generated with a repeated records model using these phenotypes. Further, we identified loci with large allele substitution effects for hair shedding. When local adaptations exist, ranking animals using a regional genetic evaluation will be different from national cattle evaluations. We developed region-specific genomic predictions using a multivariate model in which phenotypes from different regions were fit as separate dependent variables. Genetic correlations between regions were moderate, indicating substantial re-ranking between environmental regions. These genomic predictions will allow rapid identification of cattle best suited to an environment.
33 Nutritional programming of puberty in Bos indicus-influenced heifers
Authors: Cardoso Rodolfo C , Williams Gary L 
Published: December 2019

Abstract
Approximately 5 million beef heifers enter the U.S. cow herd annually and their lifetime productivity is heavily-dependent upon their ability to attain puberty and produce a calf by 24 mo of age. However, a significant proportion of heifers within existing U.S. production systems fail to achieve these goals, particularly in southern regions where Bos indicus-influenced cattle predominate. Therefore, approaches are needed that facilitate nutritional programming of the reproductive neuroendocrine axis, while minimizing feeding costs and optimizing the consistent establishment of puberty by 14–15 mo of age. Increased BW gain between 4 and 9 mo of age facilitates pubertal development by programming hypothalamic centers that regulate GnRH secretion. Among the different metabolic hormones, leptin plays a critical role in conveying nutritional information to the brain and controlling puberty. Two hypothalamic neuronal populations that express the orexigenic peptide neuropeptide Y (NPY) and the anorexigenic peptide alpha melanocyte-stimulating hormone (αMSH) are key components of afferent pathways that convey inhibitory (NPY) and excitatory (αMSH) inputs to GnRH neurons. Our studies have demonstrated that short-term increases in dietary energy intake during juvenile development result in epigenetic, structural, and functional modifications in these hypothalamic pathways to promote high-frequency, episodic release of GnRH/LH. However, integrating the foundational knowledge of metabolic imprinting of the brain for early puberty with issues related to lifetime performance is complex. One approach has been to employ a novel stair-step nutritional regimen involving alternating periods of dietary energy-restriction and re-feeding during juvenile development. This approach is designed to support early onset of puberty by imprinting functional alterations in the hypothalamus during key periods of brain development while optimizing other aspects of growth and performance. Finally, our recent findings suggest that maternal nutrition during gestation can also induce neuroendocrine changes that are likely to persist and influence reproductive performance throughout adulthood in cattle.
210 Genotype by environment interaction for pre-weaning survival in commercial crossbred pigs
Authors: Tiezzi Francesco , Fix Justin , Schwab Clint 
Published: December 2019

Abstract
Pre-weaning survival (PWS) is a trait of major importance in swine productions systems. Selection is made difficult by the low heritability of the trait(s) and genotype by environment interaction (GxE) could be present. In addition to that, given the binary nature of the trait, phenotypic variance is virtually null in contemporary group where PWS is large. The objective of this study was to assess the impact of heterogeneous phenotypic variance and GxE on PWS. We used survival to day 5 as a trait of interest, available for 574,828 crossbred piglets raised in a commercial environment. Piglets were progeny of 559 sires (450 genotyped with 60k SNP chip) and raised into 242 contemporary groups (CG). In estimating GxE, the E component was represented by fourth-order Legendre polynomials built on the CG solutions. A Single-Step random-regression sire model with heterogeneous residuals (10 classes) was used, once the CG solutions were obtained by a similar model that neglected GxE. Other (fixed) effects in the models were sow parity, litter size, litter transfer of the piglet, gender of the piglet, dam genetic line and litter (random). Results show an increase in phenotypic and residual variance as PWS decreased, which is expected given the nature of the binary trait. Genetic variance increased following the same trend, which made heritability to be constant (~2%). Genomic breeding values for most represented sires were plotted as a function of CG survival. While no variation among the sires can be found in CG with full survival, larger variance is shown as PWS decreases. Re-ranking among the sires is present as CG change. Results suggest that modeling PWS should account for the heterogeneous variance among CG. A moderate GxE in PWS at day 5 is also suggested.
223 Lesch-Nyhan syndrome: from patient to mouse model
Authors: Kubekina Marina V , Kalmykov Vladislav A , Kusov Pavel A , Silaeva Yulya Y , Deikin Alexei V 
Published: December 2019

Abstract
Introduction. HPRT1 is a Hypoxanthine-guanine phosphoribosyltransferase (HGPRT) coding gene, mutations of which cause, among other diseases, Lesch-Nyhan syndrome. LNS is a severe X-linked recessive neurological disorder. Alignment shows 98.6% homology of human and murine protein sequences. Objectives. We assume that murine model of this human disease should be developed. So, our purpose is to create a transgenic mouse model of Lesch-Nyhan syndrome by CRISPR/Cas9 genome editing system. Methods. The BLAST was used to find homologous mutation in murine HPRT1 gene comparing to Human one. X-ray crystallographic structural model of the HPRT1 was used as template for M4T Raptor algorithm to generate predicted structure of mutated protein. Models were visualized in PyMol (Schrodinger, Portland, OR). Lack of enzymatic activity of the HGPRT could be caused via troubled homodimerization. Absence of the aliphatic Valine could be the reason of the hindered monomers interaction. Genetic construction based on the px330 plasmid was brought using microinjection method in mouse fertilized ovum for producing primary transgenic organisms. Results. The CRISPR/Cas9 system was specifically designed to carry out mutations in HPRT. The resulting genetic construct was introduced into the fertilized mouse ovum to obtain primary transgenic organisms. This mouse was obtained at the Institute of Biology of the Russian Academy of Sciences. Conclusion. Homologous mutation in human and murine HPRT1 gene resulting into comparable conformational change in the protein model structure was revealed, so murine personalized model of the Lesch-Nyhan syndrome could be developed. Structural changes can be further studied to provide treatment strategy for people suffering from Lesch-Nyhan syndrome. This study was supported by Russian Science Foundation (Grant #17-75-20249).
224 Automatic image feature extraction for genetic analysis in cattle
Authors: Nye Jessica , Zingaretti Laura , Perez-Enciso Miguel 
Published: December 2019

Abstract
Image analysis has increasingly become an important tool for increasing productivity in many industries, yet its application in breeding programs is under utilized. With coat color patterns from dairy bull images, we explore automatic image analysis that extracts features which can be used in genetic analysis. In order to remove the unnecessary background information, the current methods require time consuming human inspection. Here, we present and compare a composite method that creates a mask (i.e., removes the background portion of the image) and calculates the proportion of dark and light coloration in bulls (n = 657) from the breeds Holstein and Ayrshire in dynamic backgrounds (e.g., forest, grass, hay, snow, etc.). This composite method combines the supervised algorithm MASK-RCNN, an unsupervised image segmentation approach, and k-means color clustering. The first step identifies the region of interest removing the majority of the background noise, while the second and third steps optimize the identification of the bull and segments the color patterning. We find a very low discrepancy between the proportion of white and dark between the manual curation and the composite method (+/- 1.40%); with an immense reduction in data collection time. This automatic composite method greatly improves the efficiency of complex image segmentation and analysis without compromising the quality of the data extracted, making analysis computationally feasible for large data sets. The next step is to calculate genetic parameters from these extracted phenotypes with genomic and/or pedigree data.
234 Earning public trust in gene editing
Authors: Plate-Church Amy te 
Published: December 2019

Abstract
Gene editing has tremendous potential to benefit society and food production. Yet, the social license to develop the technology to its full potential is dependent on public support and market acceptance. Traditionally it has been assumed that sound science and appropriate government oversight will result in social acceptance of innovation. What consumers want first and foremost, according to research from The Center for Food Integrity (CFI), is to know that food producers share their values, like producing safe, affordable, nutritious food in a manner that protects our environment. Sixty-five percent of U.S. consumers surveyed want to know more about how food is produced (CFI, 2017). Testing of videos about CRISPR indicate more than half of viewers want to learn more, and support for CRISPR rose from 45 to 60% when given credible, clear and understandable information. In reviewing more than 15 studies about consumer opinions on biotechnology, CFI found these consistent themes. 1) There is a considerable knowledge gap among consumers – in science and modern plant and animal breeding. 2) Before describing gene editing, it is helpful to show the evolution of genetic improvement. 3) The public wants information from credentialed experts, but they do not want an academic explanation. 4) Analogies and visuals are important to explain science, and they should be understandable without being oversimplified. 5) Consumers show strongest support for benefits of science related to environmental stewardship, healthier food and disease resistance. 6) Consumers have additional questions about use of science in animals, compared to plants. Because scientists and academic institutions among the most-trusted sources for information about biotechnology, they have a unique opportunity to effectively engage and provide information the public wants and needs to make informed decisions about gene editing.
235 Awardee Talk - Processing considerations for the pet food industry
Authors: Aldrich Charles G 
Published: December 2019

Abstract
The US is the largest pet food market in the world and produces approximately 8.5 MMT of pet food annually. Most of this is processed or cooked in some manner and fortified to be nutritionally complete with a need to assure more than 40 nutrients are met with each bite. To overlook this can lead to poor product performance, rejection by consumers, animal health issues, and recalls. Whether we consider baking, canning or extrusion, this food is subjected to some form of particle size reduction, conveyance, mixing and shear, cooking and drying process to agglomerate ingredients, provide texture and palatability, improve nutrient utilization, control spoilage, or eliminate pathogen contamination. Many of the raw ingredients are processed in similar fashion. While many benefits can be attributed to these processes, essential nutrients can be lost, utilization can be affected, unintentional compounds can be produced, shelf-keeping quality can be shortened, and sensory attributes can be altered. The objective of this review is to provide insight into significant issues that are currently being researched or should be addressed in future research. Examples from research from a variety of areas will be provided along with a discussion of mechanisms, formulation strategies, and process modifications which should be considered in order to ameliorate unintended alternations of foods intended for companion animals. Research relevant to amino acids, fatty acids, vitamins, and starch will be discussed, along with work demonstrating the impact on shelf-life, sensory qualities, and performance of pet foods.
240 True nutrient and amino acid digestibility of black soldier fly larvae differing in life stage using the precision-fed cecectomized rooster assay
Authors: Do Sungho , Koutsos Elizabeth , Utterback Pamela L , Parsons Carl M , Godoy Maria R C de , Swanson Kelly S 
Published: December 2019

Abstract
Edible insects such as black soldier fly larvae (BSFL) are alternative protein sources for animal feeds due to their high protein content and low environmental footprint. However, protein quality and amino acid (AA) content may vary across insect species and life stage. Our objective was to determine the effects of life stage on true nutrient and AA digestibility of BSFL intended for use in animal feeds using the precision-fed cecectomized rooster assay. All animal procedures were approved by the University of Illinois Institutional Animal Care and Use Committee prior to experimentation. 24 cecectomized roosters (4 roosters/substrate) were randomly assigned to test substrates [BSFL0= day 0 (day of hatch); BSFL11= day 11; BSFL14= day 14; BSFL18= day 18; BSFL23= day 23; BSFL29= day 29]. After 24h of feed withdrawal, roosters were tube-fed 20g of test substrates. Following crop intubation, excreta were collected for 48h. Endogenous corrections for AA were made using 5 additional cecectomized roosters. All data were analyzed using SAS 9.4. True dry matter, organic matter, and nitrogen digestibilities were not different among substrates, but acid-hydrolyzed fat tended to be greater (P &lt; 0.10) for BSFL23 and BSFL29 than BSFL14 and BSFL18. Although all substrates had a high digestibility, BSFL0 and BSFL11 had the lowest (P &lt; 0.05) digestibilities for most indispensable and dispensable AA. Digestible indispensable amino acid score (DIAAS)-like values were calculated to determine protein quality according to AAFCO nutrient profiles and NRC recommended allowances for dogs and cats. In general, BSFL18 had the highest and BSFL11 had the lowest DIAAS-like values for most indispensable AA. Threonine, methionine, and arginine were often the first-limiting AA. Our results suggest that BSFL are a high quality protein and amino acid source, but that life stage can affect the AA digestibility and protein quality of this novel protein source.
339 Challenges and opportunities in developing a companion animal nutrition curriculum for veterinary students
Authors: Kitts-Morgan Susanna E , Lenox Catherine , Spangler Dawn 
Published: December 2019

Abstract
Preparing future veterinarians who are knowledgeable and competent in companion animal nutrition presents distinct challenges and opportunities for veterinary educators. Students enter veterinary school from vastly different undergraduate backgrounds, which translates to students with varying degrees of knowledge related to companion animals and nutrition. Oftentimes, nutrition may be overlooked or not emphasized in veterinary curricula, resulting in new graduates who are not able to perform diet assessments for patients. Because nutrition is a fundamental cornerstone of health, veterinary educators have a responsibility to provide veterinary students with the knowledge and skills necessary to be competent in companion animal nutrition. Challenges for veterinary educators in delivering companion animal nutrition curriculum can be broadly categorized as: 1) challenges regarding lack of student knowledge of the petfood industry/companion animal nutrition, 2) challenges in student ability to apply companion animal nutrition skills, 3) challenges in preparing students for communication with clients, and 4) challenges regarding educational resources to teach veterinary students. On the other hand, many opportunities exist for veterinary curricula to incorporate nutrition effectively. These opportunities include, but are not limited to, offering basic and advanced nutrition courses, nutrition labs, and nutrition case studies. To produce veterinarians competent in companion animal nutrition, veterinary educators must identify and overcome the challenges in training veterinary students.