bluuebunny/crossref_metadata_2025 huggingface dataset:
99 Why Should the Beef Industry be Concerned About gut Health?
Authors: Penner Gregory B
Published: September 2022

The gastrointestinal tract (GIT) uses a disproportionate amount of energy relative to its weight to facilitate digestion and movement of dig, nutrient absorption, and barrier function. Through these roles, the GIT acts as the first barrier for the immune system. As such, it is clear that understanding factors that affect these functions, particular absorptive and barrier function, can help improve nutrient utilization and limit immune activation. Cattle fed highly fermentable diets provide a unique opportunity to explore functions of the GIT and improve our understanding of the connection between digestive and metabolic disorders, and infectious disease. Consistent feed intake is a major challenge facing epithelia lining the GIT as feed-deprivation: induces behavioral stress that may alter epithelial cell function increasing risk for inflammation; induces rapid reductions in absorptive surface area; reduces rates of short-chain fatty acid absorption, and results in a transient increase in GIT permeability. Upon re-feeding, cattle previously experiencing off-feed events are at high risk for ruminal acidosis. Reasons for depressed feed intake are numerous and the off-feed event imposed by many diseases may provide a theorized linkage between respiratory disease, ruminal acidosis, and liver abscesses. Recent research has highlighted that increased GIT permeability may decrease gain and alter carcass composition supportive of inflammatory-mediated responses. In addition, there is growing evidence that highly fermentable diets may alter the regional permeability; however, future research is needed to confirm these findings.
98 Gut Microbiome: Implications on gut Health
Authors: Nagaraja T G
Published: September 2022

The rumen and the hindgut, which includes cecum and colon, of cattle are inhabited by a diverse microbial community, which is composed mainly of bacteria, but also includes archaea, protozoa, fungi and viruses. Most reside in the lumen, but also colonize the epithelial surface and their compositions are a critical component of the host health. Recent advances in sequencing techniques and biological computational tools have further underscored the complexity of the microbial community. The vast repertoire of the gut microbiome provides the host complementary genetic resources to harvest energy, provide proteins and vitamins, contribute to the development of gut epithelium and gut-associated lymphoid system, and to the overall gut health. The gut epithelium-vascular interface allows secretions, and absorption and metabolism of fermentation products and serves as a selective barrier to prevent translocation and systemic dissemination of microbes, microbial toxins, and immunogens. The barrier function includes protection form mechanical damage caused by feedstuffs, chemical damage from acidity, toxins and microbial invasion, especially pathogens. The mechanisms employed likely differ between the two fermentative regions of the gut, given the dramatic difference in epithelial structures. Rumen is lined by stratified squamous epithelium compared a single layer of columnar epithelium interspersed with mucus-producing goblet cells in the hindgut. The mucus layer is the first barrier the pathogen has to overcome for colonization and translocation. An imbalance in the composition of gut microbiota, called dysbiosis, leads to gut functional disorders. The dysbiosis can range from a change in one to a few species to the perturbation of entire microbial community. The assessment of gut microbial dysbiosis is a challenge because of the complexity and huge variations in the community composition, including animal-to-animal. The gut barrier function determines whether the dysbiotic changes are contained within the lumen or disseminated systemically to affect the health and productivity.
102 Insights Into the Molecular Underpinnings of Disrupted Mammary Development and Function Arising from Late-Gestation Heat Stress
Authors: Laporta Jimena
Published: September 2022

Exposure to heat stress during a dairy cow’s dry period disrupts mammary gland remodeling impairing milk production during the subsequent lactation. The dry period coincides with late gestation, and Intrauterine hyperthermia affects offspring growth, physiology, and performance into adulthood. This presentation will highlight histological and molecular adaptations of the mammary gland under heat stress, emphasizing the carry-over effects in the dam and her progeny. Pregnant dams were either cooled (CL, fans and water soakers) or heat-stressed (HS, lack of access to cooling devices) in a free-stall setting during the dry period (~46 d) in summer. Heifers gestated under maternal heat stress or cooling (in utero heat stressed, IUHS vs. in utero cooled, IUCL) were euthanized at birth or weaning, or were followed until the first lactation to collect mammary tissue for histological, proteomics, and methylation analyses. In the dam’s mammary gland, 251 proteins and 224 phosphorylated proteins were differentially abundant in HS compared to CL. Top functions were related to immune function, inflammation, amino acid metabolism, reactive oxygen species production, tissue remodeling, and stress response. Intrauterine hyperthermia derailed mammary gland development inducing alterations in the size and weight of the whole udder and parenchyma and fat pad mass. Epithelial structures within the parenchyma of IUHS heifers were significantly underdeveloped, with reduced proliferative capacity. These early-life alterations in tissue microstructure persist through the first lactation, evidenced by IUHS mammary glands with smaller alveoli and fewer mammary epithelial cells that exhibited reduced proliferation capacity. Further, in utero hyperthermia epigenetically programed the udder. Over 130 differentially methylated genes were identified in the IUHS mammary gland with roles in development, innate immune defense, cell signaling, and transcription and translation. These studies provide insights into the molecular underpinnings of disrupted mammary structure and function arising from prior exposure to dry period/late-gestation heat stress, which led to lower milk yields of the dam and her offspring.
103 Genetic Dissection of Host Response to Heat Stress in Poultry: An “Omic” Approach
Authors: Zhou Huaijun
Published: September 2022

Climate change has significant economic impact on livestock production including poultry. Heat stress can adversely affect the health and performance of poultry. Genetic improvement by selective breeding on more climate-resilient poultry could contribute to the mitigation of negative impact on food security by heat stress. Here we utilized an experimental animal model of two highly inbred chicken lines with distinct responses to heat stress and virus infection (more-resilient Fayoumi and more susceptible Leghorn lines), and a commercial layer line (Hy-Line Brown) to elucidate genetic control of host response to Newcastle disease virus (NDV) infection under heat stress. The heat stress and immune-related tissues including liver, muscle, hypothalamus, spleen in Fayoumi and Leghorn lines were collected at multiple time points during the course of treatment (heat stress and NDV). An “omic” approach including transcriptome, proteome, metabolome, and epigenome on these tissues were conducted. Bioinformatic analysis on these “omic” data identified potential candidate genes, signaling pathways, and gene network that are associated with host response to heat stress under NDV infection. In addition, a genome-wide association analysis was conducted in Hy-Line Brown to identify genomic regions affecting physiological parameters that are indicators of host response to heat stress. This integrative and comprehensive analysis have generated many valuable novel information that can be used in further understanding molecular and cellular mechanisms of host response to heat stress, and aiding potential selective breeding for more resilient animals.
107 Restricted Feeding and Weight Loss Positively Change Fecal Microbiota Populations of Obese Dogs
Authors: Oba Patrícia M , Kostiuk Darcia , Kelly Janelle , Swanson Kelly S
Published: September 2022

Canine obesity negatively influences health and well-being and appears to negatively modify gastrointestinal microbiota populations. Restricted feeding of a specially formulated diet and consequent weight loss may be used to improve health and modify gastrointestinal microbiota. In this study, we aimed to determine the effects of restricted feeding and weight loss on fecal microbiota populations of obese dogs. All procedures were approved by the University of Illinois IACUC prior to experimentation. Twenty-four obese spayed female dogs (BW = 15.2±1.7 kg; BCS = 8.7±0.4; age = 7.2±1.6 y) were used in a 24-wk weight loss study. A control (OR) food was fed during a 4-wk baseline to identify intake needed to maintain BW. After baseline (wk 0), dogs were allotted to one of two diets: OR or a test (FT) diet and then fed to lose 1.5% BW/wk. Fecal samples were collected at wk 0, 4, 8, 12, 16, 20, and 24 for microbiota and metabolite analyses. Fecal microbiota data were evaluated using QIIME2 and Mixed Models procedure of SAS, with P< 0.05 considered significant. Alpha-diversity was affected by diet and weight loss, with dogs fed OR having a greater alpha-diversity than those fed FT. Weight loss increased alpha-diversity (wk 16, 20, and 24 > wk 0 and 4). Beta-diversity, as assessed by weighted and unweighted PCoA plots, showed separation between dietary groups and between wk 0 and all the other time points after wk 8. Weight loss increased fecal Allobaculum and Ruminococcus torques. Weight loss also increased fecal Bifidobacterium, Faecalibaculum, Parasutterella in dogs fed both diets, but greater in dogs fed OR. Weight loss decreased fecal Collinsella, Turicibacter, Blautia, Ruminococcus gnavus, Faecalibacterium, Peptoclostridium in dogs fed both diets, but greater in dogs fed OR. Our data demonstrate that restricted feeding and weight loss alter fecal microbiota of obese dogs.
106 Minimum Methionine Requirement in Adult Cats Using the Indicator Amino Acid Oxidation Technique
Authors: Pezzali Julia Guazzelli , Lambie Jocelyn G , Shoveller Anna-Kate
Published: September 2022

Despite the importance of Met for protein synthesis and a wide range of metabolic functions, little is known about its requirement in adult cats. Current recommendations for adult cats are based solely on studies using kittens and growth or nitrogen balance as the outcomes. Thus, this study aimed to determine the minimum Met requirement in mature cats using the indicator amino acid oxidation (IAAO) technique. Four adult neutered male cats (4.90 + 0.77 kg BW) were used in a Latin rectangle design. Cats were fed a semi-synthetic diet sufficient in Met for 2 weeks prior to being randomly allocated to one of the eight dietary Met treatments (0.12%, 0.17%, 0.21%, 0.28%, 0.35%, 0.42%, 0.50% and 0.57% dry-matter). Cys was provided in excess to spare the Met requirement and meet the Cys requirement. After 2d of adaptation, individual IAAO studies were performed. During each IAAO study day, cats were placed in indirect calorimetry chambers and fed 75% of their daily ration (12.38g/kg BW) split in 13 ½-hourly small meals. A priming dose of NaH13CO3 (0.44mg/kg) and L-[1-13C]-Phe (4.8mg/kg) were provided in the 4th and 5th meal, respectively, following by a constant dose (1.04mg/kg) of L-[1-13C]-Phe in the next meals. Breath samples were collected ½-hourly to measure 13CO2 enrichment to quantify 13CO2 and calculate F13CO2 during isotopic steady state (Phe oxidation). Competing models, broken-line linear (BLL) ascending model, and a broken-line quadratic (BLQ) ascending model, were fitted on F13CO2 to determine the minimum requirement of Met (breakpoint). The BLL yielded the best model with mean minimum Met requirement estimated at 0.305% (dry-matter), and the 95% confidence interval estimated at 0.521% (dry-matter) for adult cats. In conclusion, the estimated min Met requirement in this study is greater than those currently recommended by the NRC (2006; 0.17% dry-matter) and AAFCO (0.2% dry-matter).
114 Effects of Dietary Cameline oil Supplementation on Inflammatory and Oxidative Markers, Trans-Epidermal Water Loss, and Skin and Coat Health Parameters in Healthy Adult Dogs
Authors: Richards Taylor , Burron Scarlett , Grant Caitlin E , Patterson Keely , Trevizan Luciano , Minikhiem Debbie , Pearson Wendy , Shoveller Anna-Kate
Published: September 2022

Camelina oil has a desirable ratio of the essential fatty acids (EFAs) omega-3 alpha-linolenic acid (C18:3n-3; ALA), and omega-6 linoleic acid (C18:2n-6; LA). Alpha-linolenic acid supports canine skin and coat health, and inflammation. Therefore, an investigation of the effects of camelina oil on skin and coat health, and inflammation in comparison with other plant-derived EFA oil sources is needed. The objective of this study was to compare the effects of camelina oil to those of flaxseed and canola oil on skin and coat health, skin barrier function, and pro- and anti-inflammatory biomarkers. Thirty privately-owned, adult dogs of various breeds (17 females; 13 males), with an average age of 7.2±3.1 years and body weight (BW) of 27.4±14.0 were used. After a 4-week wash-in period using sunflower oil and a commercial kibble, dogs were blocked by age, breed, and size, and randomly allocated to one of three treatment oils: camelina, canola, or flaxseed. Trans-epidermal water loss (TEWL) was measured using a VapoMeter on the pinna, paw pad, and inner leg. Fasted blood samples were collected to determine serum pro- and anti-inflammatory biomarker concentrations. Prostaglandin E2 (PGE2) and Plakoglobin (JUP) concentrations were measured via enzyme-linked immunosorbent assay (ELISA) kits, while nitric oxide (NO) and glycosaminoglycan (GAG) concentrations were determined using spectrophotometric assays. A 5-point-Likert scale was used to assess skin and coat characteristics. All data were collected on weeks 0, 2, 4, 10, and 16 and assessed using PROC GLIMMIX in SAS. Follicle density, fur color, shine, and softness increased and skin moisture and dander decreased from baseline in all treatment groups (P >0.05). Outcomes did not differ (P >0.05) among treatment groups over 16 weeks, indicating that camelina oil can be considered comparable with existing plant-based canine oil supplements, flaxseed and canola, to support skin and coat health, and inflammation in dogs.
121 Comparison of Corn Fermented Protein (CFP) to Traditional Yeast and Distillers Grain fed to Healthy Adult Cats
Authors: Kilburn Logan , Aldrich Charles G
Published: September 2022

Co-products from the ethanol industry may be able to provide high-quality sustainable protein sources for pet foods. Unlike traditional co-products, corn fermented protein (CFP) contains a yeast component which may provide additional benefits. The objective of this study was to determine, by exchange, the effects of the yeast in corn fermented protein on diet utilization. The four experimental diets included a control with no yeast (CON) and diets containing either 3.5% brewer’s dried yeast (BDY), 17.5% distiller’s dried grains with solubles plus 2.5% brewer’s dried yeast (BDY+DDGS), or 17.5% CFP (CFP). It was assumed that CFP contained 20% yeast and all treatments except CON were formulated to contain 3.5% yeast. Experimental diets were fed to adult cats (n = 11) in a replicated 4 x 4 Latin Square design. Cats were adapted to diet for 9 days followed by a 5-d total fecal collection. Titanium dioxide (0.4%) was added to all diets as a marker to estimate digestibility. Data were analyzed using a mixed model in SAS (version 9.4, SAS Institute, Inc., Cary, NC) with treatment as a fixed effect and cat and period as random effects. Dry fecal output of cats was greatest for BDY+DDGS at 20.2 g/d compared with the other treatments at an average of 16.3 g/d (P < 0.05). Defecations per day were also greatest for cats consuming BDY+DDGS (P < 0.05). When comparing CFP with BDY+DDGS, the digestibility of dry matter, organic matter, and gross energy was about 3% greater (P < 0.05) for CFP. Short or branched chain fatty acids in fecal samples were not altered by dietary treatment. The increase in fecal output and decrease in digestibility with BDY+DDGS indicates a greater fiber effect in the DDGS compared with the CFP. Therefore, the yeast component in CFP may be providing a greater nutrient utilization when fed to cats.
122 Human-Grade dog Diets Dramatically Shift the Fecal Microbiome of Healthy Adult Dogs
Authors: Geary Elizabeth L , Oba Patrícia M , Swanson Kelly S
Published: September 2022

Human-grade pet foods have been shown to be highly palatable and digestible, resulting in reduced stool volume, but their impact on the gut microbiome has not been well studied. Therefore, our objective was to compare the fecal characteristics and microbiome of dogs consuming a human-grade or extruded kibble diet. Female beagles (n = 20; BW = 10.25±0.82 kg; age = 3.85±1.84 yr) were used in a completely randomized design. The diets tested were: 1) Chicken and Brown Rice Recipe [extruded; Blue Buffalo (BB)] and 2) Chicken and White Rice [human-grade; Just Food for Dogs (JFFD)]. The study consisted of a 4-week baseline when all dogs were fed BB, and a 12-week treatment phase when dogs were randomized to eat each diet (n=10/group). After the baseline and treatment phases, fresh fecal samples were collected for fecal pH, dry matter (DM), score, and microbiota analysis. Fecal bacterial DNA was extracted and shotgun sequencing was conducted using an Illumina NovaSeq, generating over 1.8 billion reads. Taxonomic and pathway abundances were calculated using MetaPhlan and HUMAnN, respectively. Fecal pH and DM were less (p< 0.05) in dogs fed JFFD than those fed BB, but fecal scores were not affected by diet. PCoA plots based on Bray-Curtis distances of bacterial genera and species showed some shifts over time in dogs fed BB, but much greater shifts in those fed JFFD. JFFD increased (adj p< 0.05) the relative abundances of 4 bacterial genera, 11 bacterial species, 129 KEGG pathways, and 167 Maaslin pathways and decreased (adj p< 0.05) the relative abundances of 16 bacterial genera, 25 bacterial species, 37 KEGG pathways, and 87 Maaslin pathways. In conclusion, the human-grade food tested vastly shifted the fecal microbiome. More research is needed to link taxonomic and gene content shifts to ingredient inclusion, nutrient concentrations, and health outcomes.
399 Freeze Dried pet Food Process
Authors: Ducklow Jared , Meidl Gerrit
Published: September 2022

Abstract The presentation will correlate mostly to pet food and will cover the fundamentals to freeze drying, the importance of recipe development, different freeze-drying applications, product yield and factors for freeze drying, the advantages of freeze drying, the parameters for freeze drying, the key aspects of freeze dryers, and some examples of meat and pet food freeze drying profiles and trends.
129 Protein and Amino Acid Modifications During Extrusion
Authors: Bosch Guido
Published: September 2022

Extrusion cooking is a high-temperature, short-time process and the foremost technique to produce attractive, nutritious and safe pet foods. As extruded foods are often routinely fed throughout the entire life of pet dogs and cats, it is important to understand the factors that influence protein quality. Protein quality, i.e. the quantity and bioavailability of amino acids, depends on the ingredients and the combination of interrelated process parameters including moisture, temperature, pressure, and mechanical shear. Few studies on the effects of extrusion of pet foods are available and both positive and negative effects on the bioavailability of proteins and amino acids were noted. Effects can in part relate to changes in the food matrix rendering proteins available for digestive enzymes. Moreover, various molecular transformations and chemical reactions can occur including denaturation, aggregation, Maillard reaction, cross-linking, oxidation, and racemisation. Denaturation of proteins is likely not important for facilitating digestion, but denaturation of enzyme inhibitors is key for plant-based pet foods as well as the reduction or elimination of non-protein anti-nutritional factors. It is clear that both ingredient selection and extrusion process parameters impact changes in quantities of bioavailable lysine via the Maillard reaction. The supply of reactive lysine can be insufficient for growing dogs and should be monitored. Bioavailability of methionine and cysteine can also be compromised due to oxidation during processing but is currently understudied. As with studies on lysine, specific analytical procedures should be applied to prevent overestimation of methionine and cysteine in pet foods. In conclusion, the extrusion is a complex process that can impact protein quality in many ways and to various degrees and more studies are required to advance our understanding of the exact underlying molecular mechanisms and to assure the quality of pet foods.
138 Age-Dependent Intestinal Barrier Repair in Suckling Pigs: A Comparative Model to Improve Neonatal Gastrointestinal Health Across Species
Authors: Ziegler Amanda L
Published: September 2022

As in porcine epidemic diarrhea virus, strangulating equine colic or necrotizing enterocolitis in human infants, intestinal diseases involving ischemic injury cause mucosal barrier damage and are associated with poorer survival in neonates. The cause of age-dependent outcomes in afflicted individuals has not been fully explained and therefore novel preventatives and treatments are lacking. While traditional rodent models have not demonstrated age-dependent differences in intestinal recovery, our translational pig model is the first to demonstrate an age-dependent intestinal barrier repair defect. We have shown that, while weaned pigs recover rapidly after ischemic intestinal injury, barrier repair is markedly impaired in suckling pigs, due to complete failure of epithelial restitution. Importantly, we found that the restitution defect in suckling pigs can be rescued by the direct application of homogenized mucosa from ischemia-injured small intestine from weaned pigs. Identifying reasons for this age-dependent defect in restitution and the components of the more mature pig mucosal tissues responsible for rescue will inform novel treatment interventions for neonates suffering with intestinal injury. Our lab has associated this age-dependent defect in barrier repair with an underdeveloped enteric glial cell (EGC) network, a postnatally developing component of the enteric nervous system known to regulate the intestinal barrier. We have found sub-epithelial EGC are reduced in neonates, neonatal epithelium in co-culture with EGC restitute more efficiently in vitro, and EGC inhibition ex vivo blocks restitution in juveniles recreating the neonatal phenotype. Further, as this EGC network is known to mature postnatally in response to the microbial colonization, we have found postnatal microbiota modulation with dietary prebiotic fiber supplementation exerts important effects on EGC network development and activity, and on EGC-epithelial pro-restitution crosstalk in vitro. Ongoing work to understand the roles of diet, microbiota, and the enteric nervous system on postnatal development of epithelial barrier repair can inform novel preventatives and interventions to improve intestinal health in vulnerable neonates.
155 Effect of Forage Inclusion Strategy on Finishing Beef Cattle Performance and Liver Abscesses
Authors: Paterson Tyen J , Penner Gregory B , Lardner Bart , Stephens Emma , Gruninger Robert J , Yang WenZhu , Beauchemin Karen A , McAllister Tim A , Ribeiro Gabriel O
Published: September 2022

This study evaluated different strategies of forage inclusion for finishing beef cattle and their impact on performance, carcass quality, and liver abscesses. Steers (n=360, 400±29 kg) were blocked by weight and randomly assigned to one of four treatments (15 steers/pen, 6 pens/treatment) in a complete randomized experiment. Treatments were: 1) positive control (+CON) fed a diet (7.5% forage on a diet DM basis) with tylosin (11 mg/kg); 2) negative control (–CON; control diet without tylosin); 3) a diet where forage concentration decreased (DECR) every 42 d and was static for the last 84 d (forage represented 15%, 9%, 3%, and 3% of DM, respectively) without tylosin; and 4) a diet where forage concentration increased (INCR), the inverse of the DECR without tylosin. There were no differences in initial BW, DMI, and G:F (P≥0.38). The INCR steers had lower ADG (1.63 vs. 1.74 kg, P=0.05), total BW gain (287 vs. 306 kg, P=0.05), and tended to have lower final BW and carcass weight (P=0.07) compared to +CON, with no differences from the other treatments. No differences were observed for carcass dressing percentage, ribeye area, marbling scores, and quality grades (P≥0.41). Backfat thickness and yield score were lower for INCR steers (14.2 mm and 3.42) compared to –CON (16.9 mm and 3.82, P=0.04), while other treatments did not differ. There was no difference for the percentage of steers with liver abscess or severe abscess (A+; P≥0.17). However, the percentage of steers with minor liver abscesses (A) was numerically less for +CON (51.8%) and DECR (51.8%) compared to –CON (62.2%) and INCR (64.3%, P=0.055). This suggests that higher dietary concentrations of forage in the beginning stages of finishing, with a subsequent decline thereafter has the potential to decrease the proportion of minor liver abscesses, similar to the inclusion of tylosin in a high-grain diet, without impacting growth performance or carcass quality.
147 The Effects of Creatine Monohydrate and Guanidinoacetic Acid Supplementation on Bovine Satellite Cells
Authors: Eckhardt Erika P , Kim WonSeob , Kim Jongkyoo
Published: September 2022

Creatine (CRE) is an energy-storing molecule of skeletal muscle and is reported as potential growth promotants. With Guanidinoacetic acid (GAA) being a precursor to creatine, the potential to evaluate supplemental GAA's role in the body from a skeletal muscle focus is needed within the beef industry. Study objectives were to evaluate the effects of CRE and GAA on bovine satellite cells (BSCs) proliferation and myogenic potential. BSCs were obtained from three-month-old Holstein calves (n=3), harvested, and incubated with 10% FBS/DMEM. Following 24h of cell adhesion, BSCs were incubated with treatments: 1) Control, 2) 10mM GAA, and 3) 5mM CRE. Cell proliferation rate was measured at 0, 24, 48, 72, and 96h. In order to identify the effects of CRE and GAA during myogenic differentiation, satellite cells were incubated in a differentiation medium (2% horse serum/DMEM) containing 10mM GAA and 5mM CRE. After 48h, cells were harvested and used for mRNA gene expression (Myh7, MyoG, IGF-1, and S6KB1). One-way ANOVA and Tukey's HSD test were used for gene expression. Two-way ANOVA and Tukey's HSD test were conducted for cell proliferation assay. No interaction effect was noted (P > 0.05) between the effects of treatment against time in end output of cell proliferation. Cell proliferation rate was not altered (P > 0.05), with proliferation rate time measurement having a greater result of cell proliferation (P < 0.001). The expression of IGF-1 was overexpressed (P < 0.05) in GAA treated BSC during the myogenic differentiation. CRE increased (P < 0.01) MyoG expression. GAA and CRE did not alter Myh7 orS6KB1 mRNA gene expression. Results suggest that the treatment of BSCs with creatine or GAA may improve myogenic differentiation and promote skeletal muscle growth via IGF-1, respectively.
146 Effect of Short-Term Nutritional Increase 30 Days Prior to Artificial Insemination on ADG and Reproductive Efficiency in Beef Heifer Development Systems
Authors: Tadich Landon F , Funston Rick N
Published: September 2022

The objective of this study was to determine if increasing nutrition 30d before AI would optimize overall heifer pregnancy rates. Angus crossbred heifers were used in a 3-yr study (n=100/yr) at the West Central Research and Extension Center, North Platte, NE. Heifers were blocked by BW and randomly assigned to 1 of 3 groups for the winter period (average 131±3.5d/yr): upland range (RANGE), dry lot low (DLLO), or dry lot high (DLHI). The same diet was offered to DLLO and DLHI until 30d prior to AI, where DLHI received increased nutrients. Heifers developed on RANGE grazed winter range with 0.45kg/d 30%CP cake until the treatment period where they received DLLO diet. Heifer ADG in DLLO (0.64±0.06kg) and DLHI (0.64±0.06kg) was greater (P=0.02) than RANGE (0.25±0.06kg) during the development period, but no differences were seen in ADG during the 30d treatment period between DLHI (1.12±0.13kg), DLLO (0.75±0.13kg), and RANGE (0.67±0.13kg). Heifers were synchronized with melengestrol acetate at 0.5 mg per head per d for 14d, and PGF2a given 19d later. Heifers were either bred on detected estrus or placed with bulls after 5d. All heifers were placed with bulls 10d following AI. Pre-breeding BWs were greater (P=0.0004) for DLHI (375.44±3.39kg) and DLLO (363.5±3.39kg) compared to RANGE (311.8±3.35kg.), but breeding ADG, between pre-breeding and first pregnancy diagnosis, was greater (P=0.0002) for RANGE (0.68±0.01kg) compared to DLHI (0.35±0.02kg) and DLLO (0.37±0.02kg). While pregnancy rates to AI were not different (P=0.43), final pregnancy rates tended to be greater (P=0.09) for DLHI (96%) and DLLO (95%) compared to RANGE (84%). No differences were observed in calving rate or heifers calving in the first 21d. While greater nutrition for DLHI and DLLO heifers led to higher BW, and tended to increase final pregnancy rates, overall short-term nutritional change had no detectable impact on AI conception.
149 Differences in Gene Expression Following Natural Exposure to Gastrointestinal Parasites between Sheep Selected for High Innate Responses and High Antibody-Mediated Adaptive Immune Responses
Authors: Willoughby Olivia B , Borkowski Emma , Dixon Samantha , Cunha Samla Marques , Asselstine Victoria , Perergrine Andrew S , Menzies Paula I , Karrow Niel A , Cánovas Angela
Published: September 2022

Parasitism by gastrointestinal nematodes (GINs) is a major source of morbidity and mortality for sheep flocks grazed on pasture. Since there is evidence for genetic resistance to GINs in some sheep breeds, genetic selection for immunologic resistance to GIN is a possible management strategy. This study sought to identify differences at the transcriptome level between Ridau-Arcott sheep characterized as high innate immune responders (IIRs, n=5) or high antibody-mediated immune responders (AbMIRs, n=5) following natural exposure to and infection with GINs after spending the summer on GIN-infested pasture; infection was confirmed with individual fecal egg counts. The transcriptomes of the high IIR and high AbMIR animals were also compared with GIN-naïve sheep of the same breed (all medium IIR and AbMIR responders, n = 7). Liver tissue samples from the 17 animals were used to perform transcriptomic analyses using RNA-Sequencing technology. The CLC Genomics Workbench 20.0.4 (CLC Bio, Aarhaus, Denmark) software was used to map reads to the most recent ovine reference genome (Oar rambouillet.v1.0.105), and for differential gene expression analysis. In total, 144 differentially expressed genes (DEG) were found between the high IIRs and the high AbMIRs (FDR< 0.05, and fold change (FC) abs > 2). When compared to the naïve animals, 136 and 53 DEG were found between them and the high IIRs and the high AbMIRs, respectively. In order to verify their function in the host immune response to GINs, functional enrichment analyses were performed on these candidate genes using the AmiGO2 software. Monocarboxilic acid metabolism was identified as an enriched biological process (FDR < 0.05), and ammonia-lyase activity and metalloendopeptidase activity were enriched molecular functions between the high IIR and high AbMIR animals (FDR < 0.05). These preliminary results improve understanding of how host resistance to GINs is genetically regulated through the innate and adaptive immune systems in sheep.
169 Evaluation and Improvement of the Nutritional Value of co-Products for Swine
Authors: Nyachoti Martin , Lee Jinyoung , Zijlstra Ruurd T
Published: September 2022

Feed accounts for the greatest portion of swine production costs, and feed cost has been increasing during the last decades due to increased competition of feed ingredients with the food and biofuel industry. Exposure to climate change is also expected to impact feed cost by changing growing conditions, and recent supply chain disruptions undermine the pricing structure for imported feedstuffs. Therefore, the need for alternative feed ingredients to ensure the economic sustainability of the swine industry cannot be overstated. To this end, utilization of co-products from the agri-processing of cereals and oilseed crops has the potential to help mitigate feed cost and to reduce the environmental footprint of pork production. In general, however, co-products of the agri-processing industry tend to be more variable in their nutrient composition and content of such anti-nutritional factors as non-starch polysaccharides, phytate, and trypsin inhibitors. For these reasons, it is critical that co-products are characterized for the nutritional value and means to enhance their nutritive value examined. We have evaluated a wide range of co-products, including canola meal, camelina meal, hemp meal, extruded soybean meal, wheat co-products, flaxseed meal, etc., and means of enhancing their nutritive values. Examined approaches to ameliorate the negative impact of anti-nutritional factors and optimize energy and nutrient availability in these co-products include: exogenous enzymes supplementation to increase nutrient digestibility, heat treatments to reduce anti-nutritional factors, and particle size reduction to increase nutrient availability. Results of many of our studies clearly demonstrate that the nutritive value of these co-products for swine can be improved significantly through the application of these approaches, thus, offering opportunities to ensure sustainable swine production systems.
175 Persistence and Serendipity: The Ecological Recovery of North American Bison Populations
Authors: Shury Todd K
Published: September 2022

Bison or buffalo were once the dominant herbivore that impacted the ecology and landscape of North American grassland and forest ecosystems from Alaska to Mexico prior to European colonization. By the early 20th century they were almost extirpated in the wild with two exceptions; in the areas that eventually became Yellowstone and Wood Buffalo national parks. Since then, private individuals, NGOs, government agencies and indigenous peoples have collaborated to restore these populations, but significant hurdles remain to achieving full ecological recovery of the species; a vision which was articulated in a landmark paper in Conservation Biology in 2008 (Sanderson et al 2008 - The Ecological Future of the North American Bison: Conceiving Long-Term, Large-Scale Conservation of Wildlife). Unfortunately, bison have been virtually erased from most people’s consciousness and imagination for over a century now, making restoration efforts for the largest land mammal on the continent particularly challenging. Despite this, several locations have had remarkable success in re-establishing wild, free-ranging bison populations in Canada, the US and Mexico over the past two decades. Bison populations have recently been re-established in Banff National Park, Alaska, and Yakutia (Siberia) and there are plans to restore populations on tribal and indigenous lands in both Canada and the US in the next 10 years. The signing of the Buffalo Treaty in 2014 was the impetus for many of the current restoration efforts on tribal and indigenous lands and indigenous groups are heavily involved in shared stewardship of these transboundary bison populations. While commercially raised bison have very different goals and vastly outnumber their wild counterparts, who are managed for ecological restoration and conservation, both groups have several shared values relating to the long-term goal of maintaining and increasing the overall number of bison in North America as well as maintaining their wild character.
180 Importance and Practices of Interaction with Producers and Industry for Land-Grant Animal Science Faculty: How are These Practices Developed and Implemented?
Authors: Whittier Jack C , Rush Ivan , Lalman David , Meyer Allison M , Mullenix Kim
Published: September 2022

The Morrill Land Grant Act of 1862 created colleges to “benefit the agricultural and mechanical arts” and established one college per state “where the leading object shall be…to teach such branches of learning as are related to agriculture…to promote liberal and practical education”. Further, the purpose of Smith-Lever Act of 1914 is “to aid in diffusing among the people of the United States useful and practical information on subjects relating to agriculture…and to encourage the application of the same”. From this legislation the role of universities was established to research and disseminate scientific information to various audiences. A key component of these legislative charges is the feedback loop between university faculty, producers, and industry professionals to assure the continuance of “liberal and practical education”. This feedback loop ensures that relevant information is pursued by faculty and provides an avenue for producer needs to be communicated back to faculty. Development of personal relationships between stakeholders and faculty is an integral part of the information flow. On-farm research and in-person educational programs, along with on-the-ground visits by faculty, have historically served an important mechanism for information flow and feedback. However, across the U.S., Animal Science undergraduate enrollment has increased dramatically while faculty and field staff extension FTEs have declined. Funding for such has remained stable over the past 20 years. These trends resulted in prioritization for undergraduate teaching and grantsmanship among faculty. The advent of electronic communications has diminished personal face-to-face interactions and on-site visits by faculty to production entities. Consulting with producers at their business often is most rewarding in learning and respected by producers, however this interaction is sometimes viewed as “service” which is viewed as a low priority by some administrators. This symposium will examine best practices by faculty to ensure land-grant universities align with the legislative mandates established by Congress and benefit from valuable interaction with clientele.
186 Effect of Feedlot Finishing Compared with Grass fed Beef Following Bale Grazing and Delayed Feedlot Entry on Steer Performance, Carcass Measurement and net Return
Authors: Senturklu Songul , Landblom Douglas G , Paisley Steve , Stroh Christina
Published: September 2022

In a grass-fed system grazing study, yearling crossbred Aberdeen Angus x Red Angus x Angus x Angus steers (n = 72; 3 reps/8 steers/rep) were assigned to either a grass-fed annual forage (GFANN) or a grass-fed native range (GFNR) system, and compared with a NR feedlot control system (FLT), in a delayed feedlot entry program, to determine the effect of grazing and feedlot finishing performance, carcass measurements, and systems net return. Data were analyzed using the MIXED procedure of SAS. After 176.0 grazing days, GFANN, GFNR, and FLT steers were transitioned to free-choice cover crop hay bale feeding (BGRZ) and 3.09 kg daily of a wheatmidd-based supplement (SUP). GFANN and GFNR received hay and SUP for 92 d; FLT control steers received hay and SUP for 69 d before transfer to the University of Wyoming feedlot. Grass-fed and FLT steers were harvested at federally inspected abattoirs in Green Bay, WI, and Ft. Morgan, CO, respectively. BGRZ gain and ADG for GFANN and FLT were greater than GFNR (P = 0.075; P = 0.072). When GFANN and GFNR bale grazing finishing costs were combined with FLT cost, feed cost/unit of gain were greater for GFANN and GFNR compared with FLT (P = 0.006). Steer FLT HCW was 26% and 34% heavier (P = 0.001), marbling score was 32% and 38% greater (P = 0.001), and carcass value was 16% and 24% greater (P = 0.001) than GFANN and GFNR, respectively. Net return was -$88.25, $62.70, and $160.22 for GFANN, GFNR, and FLT, respectively. Farming and long-haul transportation cost for GFANN and GFNR negatively affected net return.
192 Outcomes of Simulated Combinations of Rangeland Management Scenarios on Soil and Nutrient Processes
Authors: Lancaster Phillip A , Tang Minfeng , Presley DeAnn , Fick Walt , Doro Luca , Pendell Dustin , Ahlers Adam , Ricketts Andrew
Published: September 2022

The relationships among rangeland management practices and ecosystem on soil and nutrient processes are complex. Simulation models can provide valuable insight into this complexity to guide future research and management decisions for sustainable grazing systems. The objective of this analysis was to evaluate the combinations of grazing management (continuous vs. rotational), stocking rate (low, moderate, or high), and burning (none vs. annual spring burn) on soil erosion, nutrient losses, and carbon sequestration. Soil, weather, and forage species data were collected for 3 locations in the Central Great Plains (Konza Prairie Biological Station, Kansas; Agricultural Research Center-Hays, Kansas; Central Plains Experimental Range, Wyoming). These data were used to simulate combinations of rangeland management scenarios using the Agricultural Policy/Environmental eXtender (APEX) model. A stocker cattle operation was simulated at Hays, Kansas and Wyoming locations, and a cow-calf operation at Konza, Kansas location. Burning increased soil loss from water erosion regardless of stocking rate or grazing management. Rotational grazing increased soil loss at the Kansas locations, but decreased soil loss at Wyoming compared with continuous grazing. Stocking rate had little effect on nitrogen losses, but rotational grazing decreased nitrogen loss compared with continuous grazing. Greater stocking rates slightly decreased phosphorus losses with continuous grazing, but not rotational grazing. Burning decreased phosphorus losses with continuous grazing at Konza, but not the other locations. Greater stocking rates decreased the deposition of soil organic carbon especially with continuous grazing, and burning resulted in losses of soil organic carbon at Konza and Wyoming. In conclusion, rangeland management practices differentially affect nutrient processes among ecosystems such that a one-size-fits-all management scheme will not maximize retention of all nutrients in all ecosystems.
201 Forage Biodegradation: Advances in Ruminal Microbial Ecology
Authors: Callaway Todd R , Lourenco Jeferson M , Stewart R Lawton , Smith W Brandon
Published: September 2022

The rumen microbial ecosystem provides ruminant animals a selective advantage, the ability to utilize forages, which allows ruminant animals to flourish around the world in a wide variety of environments. The ability of the microbial population to convert sunlight captured in forages to high quality meat, milk, and fiber has been recognized for many years. However, the rumen microbial population composition and degradative activity has remained a “black box” with only the most active (and most amenable to laboratory growth) cellulolytic and hemicellulolytic organisms being recognized and understood. The limitation of reliance upon growth of forage degrading organisms in a test tube in order to measure the catabolic activity, severely limited the development of knowledge of the microbial ecology of ruminal forage degradation. The past 15 years has seen the development and implementation of numerous Next-Generation Sequencing (NGS) approaches, which have greatly contributed to a better understanding of the microbial ecology of ruminants fed a variety of forages. NGS has provided new insights into changes in the microbial population of ruminants fed different diets, or undergoing dietary changes. The ability to take a “snapshot” of the composition of the ruminal microbial population has furthered our understanding of the impacts of forage maturity, forage type, and phytochemicals on the degradation and fermentation of forages. We now better understand the microbial pathways that are enriched by feeding of forages and are impacted by forage quality or composition, which can further our understanding of metabolomics of the rumen. As NGS data continues to accumulate on ruminants fed forage, our understanding of the ruminal microbial ecosystem will grow both deeper and broader, allowing us to build predictive models of rumen function during forage degradation and fermentation.
204 Awardee Talk: Poor Maternal Nutrition Impacts Metabolic Factors and Glucose Tolerance in Sheep Offspring
Authors: Tillquist Nicole M , Reiter Amanda S , Kawaida Mia Y , Smith Brandon I , Reed Sarah A , Zinn Steven A , Govoni Kristen E
Published: September 2022

To evaluate the hypothesis that offspring born to restricted- and over-fed ewes would exhibit decreased glucose tolerance, total cholesterol (TC), and triglyceride (TG), and increased leptin, multiparous Dorset ewes (n = 46) pregnant with twins were fed 100%, 60% or 140% of National Research Council (NRC) requirements from d30±0.02 of gestation until parturition. Offspring are referred to as CON (n=10 ewes; 12 rams), RES (n=13 ewes; 21 rams), and OVER (n =16 ewes; 15 rams), respectively. Blood samples were collected from offspring at d0, 7, 14, 58, 210, and 252 of age and plasma TC, plasma TG, and serum leptin were analyzed with commercial kits. Concentrations of TG were greater in rams than ewes (P=0.029). Leptin was greater (P< 0.0001) in ewes than rams at d30 and 36, and greater in CON than RES and OVER at d252 (P=0.058). At d133±0.25 an intravenous glucose tolerance test was performed, and blood samples collected at -30, -15, 0, 2, 5, 10, 15, 30, 60, and 120 min relative to glucose infusion (0.25 g/kg body weight of a 50% dextrose solution). Glucose and insulin concentrations were determined using commercial kits. Glucose concentrations were greater at 5 and 15 min in ewes than rams (P≤0.04) and at 2 min, OVER were greater than CON and RES (P=0.03). Insulin concentrations were greater in rams than ewes between 5 and 15 min (P=0.0251). Insulin in RES rams tended to be greater than OVER and RES ewes between 5 and 10 min (P=0.06) and continued to be greater than RES ewes at 15 min (P=0.05). First-phase response of insulin tended to be greater in RES compared with CON and OVER (P=0.092). There were no differences detected in insulin:glucose (P=0.312). In conclusion, poor maternal nutrition negatively impacts key metabolic hormones in offspring thereby contributing to altered growth and metabolism.