bluuebunny/crossref_metadata_2025 huggingface dataset:
75 The Power of Theoretical and Practical Identifiability Analysis for Modeling (Micro-) Biological Processes
Authors: Muñoz-Tamayo Rafael
Published: September 2022

When modeling biological systems, one major step of the modeling exercise is the confrontation between the theory (the model) and the reality (the data). Such a confrontation passes through the resolution of the parameter identification (model calibration) problem, which aims at finding a set of parameters that best fits the variables predicted by the model to the data. The parameter identification step is often addressed like a downstream process. Using this approach, once the data are collected, the modeler has a minimal degree of freedom to improve the accuracy of her model. Instead, the modeler can identify opportunities for improving model accuracy if the parameter identification problem is addressed like an upstream process. For instance, one of these opportunities is to determine for a given experimental setup (before the actual data collection), whether the optimization problem is well-posed (that it is, if the problem has unique solution). Knowing this information beforehand is useful to set up an experimental protocol that guarantees the uniqueness of the parameter estimates. This question of uniqueness is related to the notion of structural (theoretical) identifiability. The modeler might also be interested in knowing whether the available data that will result from the experimental protocol will be informative enough to identify the model parameters accurately. The question of parameter accuracy based on the quality of available data is related to the notion of practical identifiability. This work aims to present the theoretical basis of structural and practical identifiability analysis. By capitalizing on the use of dedicated software tools, we will illustrate further the power of structural and practical identifiability analysis in the modeling exercise using relevant examples for the modeling of microbiological processes such as the rumen microbial fermentation.
73 Building Models for Animal Production and Management with System Dynamics
Authors: Turner Benjamin L
Published: September 2022

The learning objectives of this workshop session are to be able to define system dynamics (SD), the core variables used in SD simulation (stocks, flows, and auxiliaries), and mental models. In order to achieve this, participants will build a small, simple SD model and run several preliminary tests to explore changes in dynamic behavior patterns. Several other case studies will be presented and discussed. By completing the exercises and interacting with the case study material, participants will gain a greater appreciation for the ways in which systems analysis using models can help address complex animal science or general agricultural resource problems as well as engage students in active and problem-based learning.
80 Effects of Prenatal Stress on Beef Steer Development
Authors: Elder Kasey A , Fernandez Rachel , Dunn Rachel , Green Kiana , Odhiambo John F , Coble Derrick
Published: September 2022

Cost-effective growth in beef steers is necessary for limited-resource grass-fed cow-calf operations. Therefore, production goals should emphasize using inexpensive feed sources to maximize growth post-weaning. Maternal stress during gestation can negatively affect this progression. Effects of prenatal stressors such as hurricanes have been overlooked. In this project two groups of steers born from the same lineage in different years were compared: Group 1, dams experienced effects of a category 5 hurricane in their late gestation. Group 2, dams experienced no adverse environmental effects. Body weights were collected at 13 (Period 1), 14 (Period 2), and 20 months of age (Period 3). Blood cortisol concentrations were evaluated in Summer (when Group 1 average age was 31 months, while Group 2 averaged 18 months of age) and Fall (when Group 1 average age was 34 months, while Group 2 average age was 21 months) periods. Data were evaluated by mixed procedures of SAS, and significance was declared at P< 0.05. The results showed a significant group effect on the age-matched body weights (572.96±22.04 vs 735.12±22.04, lbs. for groups 1 and 2 respectively). Period effect was also significant (P< 0.001). However, there was no group by period effect. Group 1 steers were lighter in body weight than Group 2 in periods one and two but were not different thereafter. There was a significant group effect on cortisol concentrations (965.24±38.21 vs 1,282.2±40.53, pg/mL for groups 1 and 2 respectively). Our results showed that the hurricane had detrimental effects on steers, which may impede the growth progression of animals as seen in this study. The observations made in this study indicate the need to investigate further the effects of prenatal stress by natural disasters on beef steer development.
91 Key Economic and Marketing Trends in fed Cattle and High-Quality Beef
Authors: McCullock Katelyn , Robb James
Published: September 2022

This presentation provides a descriptive overview of economic and marketing trends and key changes in cattle feeding over the last two decades. The focus will highlight four major areas: aspects of beef demand (domestic and foreign), market-driven carcass characteristics, economically driven producer production trends, and marketing arrangements. The last two decades have brought unique challenges and opportunities to the beef industry through demand changes and production technologies. Consumer diet trends, the rise and fall of saturated fat, and the expansion into the global marketplace have all shaped the beef demand profile. New technologies also have shaped feedlot management and marketing. Over the last two decades, changes have revolutionized fed cattle marketing, rewarding quality through alternative marketing arrangements, especially formula pricing, including grid pricing. Evolutionary changes have been seen in carcass grading characteristics (e.g., Choice/Select price spread) and helped focus production practices to zero in on producing higher-quality beef. Trends at the feedlot such as carcass weights, days on feed, and other productivity measures have also been shaped by in-part by economics. Last, we will offer a few comments on emerging issues and trends.
95 Micronutrient Research Needs for the Next Beef Nasem
Authors: Hansen Stephanie L , Drewnoski Mary E , Smerchek Dathan T
Published: September 2022

NASEM committee members must work with freely available data to adjust current nutrient recommendations. This presentation will highlight fundamental questions with which the next committee will need to wrestle. How relevant are the foundational studies upon which current recommendations were built, given the genetic, technological, and husbandry advances of the beef industry over the past several decades? Should the next beef NASEM adopt the policy of the latest dairy NASEM and use a factorial approach to mineral recommendations? What studies are necessary to even make this a possibility? Discussion of the pros and cons to such an approach will occur, as will discussion of other critical research needs regarding micronutrients. For example, dose titration studies with both minerals and vitamins are needed for all stages of beef cattle, more pressing for some nutrients than others. These studies need to include negative controls, and to assess performance and biological measures (e.g. enzymatic activity) and can be quite expensive. Beef cattle feedstuffs are regionally dependent and largely cost-based. The effect of diet type on mineral and vitamin bioavailability would be useful. Additional discussion of the major needs for cows and calves (e.g. vitamin A, vitamin E) and weaned to finish (e.g. P, Co, Zn) will be covered.
101 Intestinal Barrier Dysfunction: Causes and Metabolic Consequences
Authors: Kvidera Sara K
Published: September 2022

The intestinal epithelium has two critical roles: nutrient absorption and protection against numerous pathogens and antigens present in the gastrointestinal tract (GIT). The GIT is thought to be the evolutionary developmental site of the original immune system which later progressed into adding more specialized tissues. The GIT contains an enormous surface area to defend against invading pathogens and contains the majority of the body’s immune cells. Poor gut health can be caused by a variety of stressors, and ruminant research has characterized the negative impacts of rumen acidosis, heat stress, and feed restriction (FR) on lower gut health. Recently, FR has been utilized as a model to study negative consequences of GIT health and strategies to ameliorate it. The mechanism by which FR causes barrier dysfunction is not known but could be due to a lack of luminal nutrients or associated psychological stress. If stress causes GIT health to be compromised to the point where pathogens/antigens cross into the host animal and if the insult is severe enough, systemic inflammation can ensue. Inflammation is energetically costly, in part because activated immune cells have a preferential appetite for glucose. Inflammation also alters basal and stimulated metabolism, likely to help support glucose sparing for immune system use. This is extremely costly to the producer, as an animal must mobilize valuable skeletal muscle stores or compromise milk (lactose) production to ensure adequate glucose for survival. In an intensely activated immune system, it has been estimated that ~1.0 g glucose / kg BW0.75 / hour is utilized to mount a response. Therefore, it is important for producers to minimize stresses known to compromise gut integrity and for nutritionists and allied industry personnel to understand and utilize nutritional strategies and interventions to protect GIT health.
104 Standardized Amino Acid Digestibility of Three Formats of Freeze-Dried dog Foods Using the Precision-fed Cecectomized Rooster Assay
Authors: Oba Patrícia M , Utterback Pamela L , Parsons Carl M , Templeman James , Swanson Kelly S
Published: September 2022

Freeze-dried pet foods represent a small segment of the pet food market, but its growth has been significant in recent years. Despite their increasing popularity, freeze-dried diets have not been well tested. Therefore, the objective of this experiment was to determine and compare the standardized amino acid (AA) digestibilities of freeze-dried dog foods using the precision-fed cecectomized rooster assay. Three formats of freeze-dried diets provided by Primal Pet Foods (Fairfield, CA) were tested: traditional freeze-dried nuggets (FDN), low-temperature freeze-dried nuggets (LTN), and a hybrid freeze-dried nugget (HN). All animal care procedures were approved by the University of Illinois Institutional Animal Care and Use Committee prior to experimentation. Twelve cecectomized roosters (4 roosters per substrate) were randomly assigned to the three test substrates. After 24h of feed withdrawal, roosters were tube-fed 12-13g of test substrates and 12-13g of corn. Following crop intubation, excreta (urine and feces) were collected for 48h. Endogenous corrections for AA were made using 5 additional cecectomized roosters. All data were analyzed using the Mixed Models procedure of SAS version 9.4. There were no significant differences in standardized AA digestibilities among diets, with digestibilities being high for all tested. For most of the indispensable AA, digestibilities were greater than 90% for all diets (arginine: 94.1%-95.6%; isoleucine: 91.2%-93.1%; leucine: 92.4%-95.3%; methionine: 92.8%-94.9%; phenylalanine: 90.8%-93.6%; tryptophan: 96.2%-98.6%; valine: 90.2%-92.9%). Histidine, lysine, and threonine were the exceptions, with digestibilities ranging from 81.7%-86.6%, 86.7%-91.7%, and 89.6%-91.7%, respectively. Moreover, the reactive:total lysine ratio, a measure of heat damage, ranged from 0.91 to 0.95. In general, the low-temperature nugget had thegreatest numerical AA digestibilities, likely due to reduced heat damage, but all diets performed very well.
108 Citrus oil Extract Potentiates the Antifungal Efficacy of Whey Protein Fermentate AgainstAspergillus Flavus in Semi-Moist pet Treats for Dogs
Authors: Kiprotich Samuel
Published: September 2022

Semi-moist pet treats contain moisture content ranging from 20-30% making them ideal for mold growth and mycotoxin production. To control spoilage, synthetic mold inhibitors, such as potassium sorbate, have been used. Unfortunately, consumers would prefer “natural” preservatives. Whey protein fermentate (WPF) is an efficient antifungal, albeit in large doses. Therefore, the objective of this study was to determine the effect of citrus extract (CX) to potentiate WPF against Aspergillus flavus in semi-moist pet treats. Nioutritionally complete semi-moist dog treats were produced with WPF alone [0.25%, 0.5% and 1.0% (w/w)] or in combination with CX [0.25% WPF+ 0.015% CX, 0.25% WFP+ 0.15% CX, 0.5% WPF+ 0.015% CX, 0.5% WFP+ 0.15% CX (w/w)]. The negative control (NC) contained no antifungal additive and the positive control had potassium sorbate (0.1% w/w). Treats were baked into 3cm x 3cm squares. Individual squares were inoculated with 0.1 mL of Aspergillus flavus (ATCC 204304) to achieve a final concentration of ~ 5.0 Log CFU/square. The inoculated squares were individually incubated at 250 C. Fungal analysis was performed at day 3, 6, 9, 12, 15, 18, 21, 24 and 28 by surface plating on Potato Dextrose Agar (PDA) followed by incubation at 250 C for 72h. The total log reductions were calculated by subtracting the initial inoculum with the colony counts on day 28. Log reductions of Aspergillus flavus (P< 0.05) were observed when WPF at 0.25% and 0.5% were added with 0.15% CX compared with when 0.015% CX was applied. All treatments were different from the NC (P< 0.05). Citrus extract at 0.15% potentiated the antifungal potency of WPF at 0.5% to give a similar log reduction (P >0.05) to WPF at 1.0% the treats. In conclusion, CX reduced the dose of WPF required to control Aspergillus flavus in semi-moist dog treats.
113 Immunological Effects of Ganoderma Lucidum Supplementation in Canine Nutrition
Authors: Kayser Emanuela , He Fei , Gomez Luis M , de Godoy Maria R
Published: September 2022

Ganoderma lucidum (GL) is a mushroom that has been widely used in Asia for its immunomodulatory, anti-inflammatory and anti-tumor capacity in humans. However, the nutraceutical properties of GL have not been tested in dogs. Forty adult beagles were used in a completely randomized design and were fed a commercial dry extruded complete and balanced diet plus GL top-dressed daily upon feeding time. Four experimental treatments were used: 0% GL supplementation (control), 5 mg/ kg BW of GL, 10 mg/ kg BW of GL, or 15 mg/kg BW of GL. Following a 7 d adaptation to the control diet, dogs were fed their respective treatment diets for consecutive 28 d. They were challenged with vaccination of a modified live virus Canine Distemper, Adenovirus Type 1 (Hepatitis), Adenovirus Type 2, Parainfluenza, and Parvovirus and killed Rabies Virus on d 7 with blood collections on d 0, 14, and 28. The objective of the present study was to evaluate the effects of dietary inclusion of GL on peripheral blood mononuclear cells (PBMC; T-cells, B-cells, monocytes, and natural killers) and vaccine titers response of adult dogs. The inclusion of GL in all dosages was well-accepted by all dogs. There was a trend that the percentage of MHC-II from B-cells was greater in dogs fed 15 mg/kg of GL (41.91%) compared with the control group (34.63%). The phagocytosis response tended to have treatment by time interaction among treatments; dogs fed 15mg/kg of GL tended to have greater phagocytosis activity on d 28 than dogs from the control group and dogs fed 5mg/kg of GL. These data suggest that the inclusion of GL had no detrimental effects on analyzed PBMC. Based on our findings, GL may also exert beneficial immunomodulatory effects in healthy adult dogs when provided at a daily dose of 15 mg/ kg BW.
116 The Effects of Dietary Phenylalanine on Gastric Emptying, Macronutrient Metabolism and Feed Intake in Healthy Adult Cats
Authors: Lambie Jocelyn G , Pezzali Julia Guazzelli , Singh Pawanpreet , Shoveller Anna-Kate
Published: September 2022

Phenylalanine (Phe) consumption may delay gastric emptying (GE) and feed intake. Two studies were conducted using a 2*2 latin square design with 12 healthy male cats to evaluate effects of 1) dietary Phe (PHE, 44mg/kg-BW) compared with an isonitrogenous amount of alanine (ALA, 23.7 mg/kg-BW) on feed intake, and 2) PHE and ALA on GE and GE rate (GER). In study 1, cats were given PHE or ALA 15 minutes before 120% of their daily food and intake was measured. Treatment, day, and their interaction were evaluated using PROC GLIMMIX in SAS. Treatment did not affect rate of food consumption (p >0.05). For study 2, cats were provided PHE or ALA 15 minutes before receiving 100% of their daily food intake for 3 days. On d4, cats received PHE or ALA and subsequently received [1-13C] octanoic acid (5mg/kg BW) on 10g of feed before being fed 50% of their daily food intake. Breath samples were collected to measure 13CO2 enrichment for 12 hours post-meal using indirect calorimetry. Data from cats that returned to baseline enrichment were evaluated for total AUC (GE) and time to peak enrichment (GER). The effect of treatment, body condition score (lean vs. overweight), and their interaction were evaluated using PROC GLIMMIX in SAS. Cats receiving PHE had later peaks (445±71 min) in 13CO2 enrichment (p< 0.05) than cats receiving ALA (244±71 min) but had similar total GE (p >0.10). Obese cats tended (P=0.09) to have greater total GE than lean cats, regardless of treatment. Lean cats on PHE had slower (p< 0.05) emptying rates than lean cats on ALA, but both were similar to obese cats (p >0.05). Overall, Phe did not reduce feed intake or total GE but did delay GE and thus reduced GER. A longer study is warranted to understand whether PHE can control food intake in cats.
117 Assessment of Complete Blood Count and Biochemistry Parameters in Adult Dogs fed a Grain-Free Diet with up to Forty-Five Percent Pulse Inclusion
Authors: Singh Pawanpreet , Banton Sydney , Templeman James , Raheb Shari , Saunders-Blades Jennifer , Kostiuk Darcia , Kelly Janelle , Verbrugghe Adronie , Shoveller Anna-Kate
Published: September 2022

With interest in grain-free diets (GFD) and plant-based diets, understanding the use of pulse ingredients is warranted. Recently our laboratory found that high pulse inclusive diets did not cause echocardiographic changes in healthy adult dogs after 20 weeks of feeding. Thus, the objective of this study was to assess the safety of pulse ingredient inclusion up to 45% in canine diets using gross physiological, hematological and biochemical measurements. Twenty-eight healthy adult Siberian huskies were fed one of four experimental diets formulated to achieve the same macronutrient targets and the same micronutrient supplementation for 20 weeks: 1) grain-inclusive diet, with 45% corn, 0% pulses (Control); 2) GFD, 15% pulses (Pulse15); 3) GFD, 30% pulses (Pulse30) 4) GFD, 45% pulses (Pulse45). All diets included chicken meal and the same combination of pulse ingredients; green and yellow peas, pinto beans, chickpeas, and lentils. Dogs were fed once daily. Body weight was measured weekly, feed intake measured daily, and body composition was measured using DEXA at baseline and week 20. Fasted blood samples were collected at weeks -3, 3, 6, 10, 14 and 18. Data were analyzed as repeated measures in SAS using PROC GLIMMIX. Body weight, body composition, and feed intake were similar among treatments and over time (P >0.05). Several blood parameters were different among treatments but remained within defined reference ranges for healthy dogs. Red blood cells, hemoglobin and carbon dioxide were greater, while lymphocytes were reduced in Pulse45 than Pulse15 (P< 0.05), but similar to Control and Pulse30. Mean corpuscular hemoglobin concentration was decreased in Control and Pulse15 compared with Pulse30 and Pulse45 (P< 0.05). Gamma-glutamyl transferase was less in Control and Pulse15 than Pulse45 (P< 0.05), but similar to Pulse30. These data suggest that feeding diets with up to 45% pulse inclusion for 20 weeks does not impact gross health parameters of healthy adult dogs.
118 Functional Properties of Bifidobacterium Animalis Subsp. Lactis Cect 8145 in Canine Nutrition
Authors: Kayser Emanuela , He Fei , Davenport Gary M , de Godoy Maria R
Published: September 2022

The gut bacterial population has been demonstrated to influence the physiologic and metabolic functions of the host by modulating energy expenditure and immune response, therefore contributing to the health of the host. However, there is little information regarding the effects of probiotics and postbiotics on canine nutrition. The objective of this study was to evaluate the longitudinal effects of daily supplementation of Bifidobacterium animalis subsp. lactis CECT 8145 and the same strain in a heat-killed presentation (postbiotic) on weight management, fecal fermentative end-product concentration, gut hormones, postprandial glycemic and insulinemic response in overweight dogs. Thirty-six adult dogs were used in a completely randomized, double-blinded, placebo-controlled study, with 12 animals per treatment. Dogs were fed a commercial dry extruded complete and balanced diet twice daily to maintain body weight. Following a 60 d adaptation to the control diet, dogs were fed their respective treatment diets for 90 d. Treatments were provided by ADM Biopolis (Valencia, Spain) and given via gelatin capsules before morning feeding to ensure consumption of the total dose of their placebo, probiotic, or heat-killed probiotic. The treatments supplementation had no detrimental effect on the overall dog's health. Throughout the experimental period, fecal scores did not differ among dogs fed different dietary treatments (P > 0.05). However, fecal pH was significantly lower (P = 0.0049) in the dogs fed the postbiotic (5.8) compared with the group control (6.1). Greater fecal concentration of propionate (P=0.0427) was observed on dogs fed the probiotic and the dogs fed the postbiotic compared with the group control. Pancreatic polypeptide plasma concentration was less (P < 0.05) in the dogs fed the probiotic compared with treatment control. These data suggest that the longitudinal supplementation of this specific strain in the live and heat-killed presentation may interact with gut microbial fermentation and gut hormonal regulation.
124 The Acute Effects of Supplementing a Meat-Based Diet with a Combination of Creatine, Carnitine and Choline, Taurine or Methionine on Post-Prandial Plasma Creatine and Creatinine Concentrations in Dogs
Authors: Banton Sydney , Braun Ulrike , Pezzali Julia Guazzelli , Shoveller Anna-Kate
Published: September 2022

Creatine is an essential nitrogenous compound for cellular energy homeostasis in vertebrates. It is synthesized from the methylation of guanidinoacetate, a metabolite of arginine and glycine. Creatine is found in animal protein, however, when heat-processed for pet food, the creatine content decreases dramatically and creatinine is formed. Previous data from this study have been presented, however, the current objective was to define the postprandial plasma creatine and creatinine response in dogs fed a commercial meat-based diet (CON), top-dressed with a combination of creatine, carnitine and choline (CCC) or other nutrients involved in methyl metabolism, methionine (MET) or taurine (TAU). The control diet contained 0.195 g/kg creatine and 0.563 g/kg creatinine on an as-fed basis. Eight adult Beagles were fed one of the four diets for 7 days in a Latin Square design. On day 7, dogs had cephalic catheters placed and a series of blood samples were collected at fasted and up to 6 hours post-meal. Creatine and creatinine were analyzed using HPLC and data analyzed using Proc Glimmix in SAS (Version 9.4). Plasma creatine concentrations were greater in dogs fed CCC (103±10 µmol/L) compared with MET (72±7 µmol/L) at fasted (P< 0.05) and greater compared with all other treatments from 15 to 360 minutes post-meal (P< 0.05), with a peak concentration of 735±74 µmol/L at 90 min. Plasma creatinine concentrations were greater in dogs fed CCC from 60 to 180 min post-meal compared to all other treatments (P< 0.05), with a peak concentration of 223±13 µmol/L at 90 min. Both peak concentrations were outside of established reference ranges in dogs. These data suggest that when creatine is top-dressed for 7 days, plasma creatine remains increased at fasted and up to 6 hours post-meal, while plasma creatinine remains increased up to 3 hours post-meal, which has implications for energy production and methyl metabolism.
123 Effects of a Saccharomyces Cerevisiae Fermentation Product-Supplemented Diet on Fecal Characteristics, Oxidative Stress, and Blood Gene Expression of Adult Dogs Undergoing Transport Stress
Authors: Yotis Sofia , Norton Sharon A , Panasevich Matthew , Oba Patrícia M , Koziol Samantha , Swanson Kelly S
Published: September 2022

Previously, a Saccharomyces cerevisiae fermentation product (SCFP) was shown to positively alter fecal microbiota, fecal metabolites, and circulating immune cell function of adult dogs. The objective of this study was to measure the effects of SCFP on fecal characteristics, serum oxidative stress biomarkers, and whole blood gene expression of adult dogs undergoing transport stress. Sixteen adult pointer dogs (8M, 8F; mean age = 8.35 y; mean BW = 27.13 kg) were used in a randomized crossover design study. All dogs were fed control diet for 4 wk, then randomly assigned to a control or SCFP-supplemented diet and fed to maintain BW for 11 wk. A 6-wk washout preceded the second 11-wk experimental period with dogs receiving opposite treatments. After 11 wk, fresh fecal and blood samples were collected before and after transport in a van for 45 min. Change from baseline data (i.e., before and after transport) were analyzed using the Mixed Models procedure of SAS 9.4, with P< 0.05 being significant and P< 0.10 being trends. Changes in serum malondialdehyde and 8-isoprostane:creatinine concentrations increased (P< 0.05) in dogs fed SCFP, but decreased in control dogs with transport stress. Other serum markers were unaffected by diet during transport stress. Fecal dry matter percentage tended to be affected (P< 0.10) by diet during transport stress, being reduced in control dogs, but stable in dogs fed SCFP. Other fecal characteristics were unaffected by diet during transport stress. Blood cyclooxgenase-2 and myeloperoxidase mRNA expression was affected (P< 0.05) by diet during transport stress, being increased in control dogs, but stable or decreased in dogs fed SCFP. Expression of other genes was unaffected by diet during transport stress. These data suggest that the benefits of feeding a SCFP in a novel transport stress model are mediated more so by suppressing innate immune cell activation than through decreasing lipid peroxidation.
127 Standardized Amino Acid Digestibility and Protein Quality of Extruded Canine Diets Containing Hydrolyzed Protein
Authors: Hsu Clare , Utterback Pamela L , Parsons Carl M , Marx Fabio , Guldenpfennig Ryan , de Godoy Maria R
Published: September 2022

Hydrolyzed protein in companion animal diets has been of public interest because of itsdecreased susceptibility to elicit overreacting immune response and the potentially easier digestion. Thus, the objective of this study is to determine the chemical composition, standardized amino acid digestibility, and protein quality of 2 test protein hydrolysates, chicken liver hydrolysate (CLH) and chicken hydrolysate (CH), compared with a traditional chicken meal low ash (CM) in extruded canine diets. Five treatment diets were formulated to have similar ingredient compositions except for the main protein source, 1) CONd: CM diet; 2) 5%CLHd: 5% substitution of CLH of CM diet; 3) CLHd: CLH diet; 4) 5%CHd: 5% substitution of CH of CM diet; 5) CHd: CH diet. A precision-fed rooster assay using cecectomized roosters (n=4/treatment) was conducted to determine the standardized amino acid ileal digestibility and Digestible Indispensable Amino Acid Score (DIAAS) like values for the 3 protein ingredients and 5 extruded diets. The standardized ileal digestibility for the 10 indispensable amino acids was all equal or greatere than 80% in all protein sources and treatment diets. Tryptophan digestibility in 5%CLHd was less than CLHd (P < 0.05) but no difference was seen when compared with the other diets (P > 0.05). The DIAAS-like values of the diets according to AAFCO nutrient profile showed that tryptophan was the first limiting amino acid for CONd, 5%CLHd, and 5%CHd; the diets containing only protein hydrolysates had no limiting amino acid as their DIAAS-like values were greater than 100%. The DIAAS-like values were less in CONd (95.6%), 5%CLHd (94.9%), and 5%CHd (96.2%) compared with CLHd (104.5%) and CHd (116.9%) (P < 0.05). In conclusion, all test protein sources were well digested; however, substituting CM with protein hydrolysate could increase protein quality in canine extruded diets.
137 Standing in the gap of Neonatal Microbe-Host Barrier Function
Authors: Burrin Douglas , Hebib Valeria Melendez
Published: September 2022

The provision of mammary secretions in the form of colostrum and mature milk for newborns is an essential survival function that has evolved over millennia in mammalian species. Colostrum serves a vital function for neonates by providing nutrients for energy and growth as they transition from placental nutrition to oral ingestion of more complex macromolecules, including lactose, proteins, and triglycerides. Colostrum also provides critical immune protection from colonizing commensal and pathogenic microbes that supports neonatal immunity until maturation of the immune system. This concept of homologous passive immunity conferred by colostrum is well known in farm animal species and has been largely attributed to immunoglobulins transferred from mother to offspring. Heterologous passive immunity is also an approach whereby bovine colostrum obtained from normal or hyperimmunized cows is used therapeutically to prevent specific GI diseases in swine and human infants. The critical importance of colostrum to survival of newborn farm animals also holds true in the prevention of intestinal diseases, such as necrotizing enterocolitis (NEC), in hospitalized premature infants. In preterm infants, mother’s own milk may not always be available and infants are instead fed donor human milk, which provides effective protection against NEC. Whether the benefits of human milk in the prevention of NEC are due to immunoglobulins is not well established. These scenarios whereby colostrum from different species or different mothers within a species protect the neonatal gut point to common elements of host protection. New experimental approaches and tools are being applied to understanding the molecular mechanism of how components of maternal milk impact gut microbial colonization and interaction with the host immune system.
140 Redefining gut Barrier Function for Beef and Dairy Cattle
Authors: Penner Gregory B
Published: September 2022

Of the many roles that the gastrointestinal tract (GIT) must facilitate, coordinated regulation of molecule movement across the gastrointestinal is key. This coordinated regulation allows for nutrient absorption while limiting permeation of non-desired molecules and is referred to as barrier function. Barrier function of the GIT includes intrinsic, extrinsic, and immunological factors, but generally permeability assessments are conducted to evaluate the whole-animal response and most studies focus on the extrinsic components of GIT barrier function. Common approaches to evaluate GIT permeability include the use of inert external markers varying in size and their measurement in blood or urine. Methodology exists for ex vivo, in vitro, and in vivo assessment; however, only in ex vivo and in vitro methods currently allow regionally specific information. Moreover, ex vivo studies have been essential to further elucidate factors that affect permeability such as osmolality, pH, and bioactive components such as histamine and lipopolysaccharides. For ruminants, extensive microbial degradation challenges the use of fermentable substrates as markers when assessing permeability and there is interest to compartmentalize permeability by region of the GIT. Recent research using dual markers to allow for total GIT and post-ruminal permeability have highlighted that regional permeability responses may be affected by production system, environmental conditions, and dietary characteristics. Future research is needed to improve the understanding of factors that affect GIT permeability, the regions involved, and strategies to support regulation of permeability.
139 Calcium-Sensing Receptor and the Regulation of Nutrient Absorption and gut Health in Pigs
Authors: Yang Chengbo , Zhao Xiaoya
Published: September 2022

The gut has a network of G protein-coupled receptors (GPCR) that can recognize nutrients, other chemicals, and microbes and then initiate a cascade of signals to regulate nutrition, gut function, and metabolism. Calcium sensing receptors (CaSR) belong to the GPCR family and are expressed in various animal tissues, and CaSR plays important role in nutrient sensing and the physiology, growth, and development of animals. Our results demonstrated that pCaSR is widely expressed in different tissues including intestinal segments in weaned piglets and the ileum has a higher expression level of pCaSR. However, pCaSR is not expressed in either isolated porcine ileal enterocytes or intestinal porcine enterocyte cell lines (IPEC-J2). We also found that the activation of pCaSR showed biased agonism through multiple signaling with a dual-luciferase reporter assay system. Besides, α-casein (90-95) and L-Tryptophan (L-Trp) are type II agonists for pCaSR. We investigated the roles of pig calcium-sensing receptor (pCaSR) ligands in gut hormone secretion and mechanism and the effects of pCaSR ligands on inflammation response, nutrient absorption and barrier function in the intestinal epithelial cells co-culture system challenged with peptidoglycan (PGN). Our results demonstrated that the pCaSR ligands (L-Trp and α-casein (90-95)) to STC-1 cells could induce the secretion of gut hormones through the regulation of CaSR in STC-cells. Plus, the GLP-1 secretion triggered by L-Trp and α-casein (90-95) in STC-cells attenuated the inflammation response, improved the nutrient absorption and barrier function in the IPEC-J2 cells. Further research is still needed to elucidate the roles of L-Trp and α-casein (90-95) on nutrient absorption and barrier function in pigs under physiological challenges. Collectively, the pCaSR is widely expressed in the porcine tissues, and the activation of pCaSR has the potential to improve gut health and growth performance in swine production.
152 Effect of Continuous or Intermittent Feeding of Ergot Contaminated Grain in a Mash or Pelleted Form on the Performance of Backgrounding Beef Steers
Authors: Reynolds Matthew R , Stanford Kim , Meléndez Daniela M , Schwartzkopf-Genswein Karen S , McAllister Timothy A , Blakley Barry R , McKinnon John J , Ribeiro Gabriel O
Published: September 2022

The objective of this study was to evaluate the effect of feeding pelleted or mash ergot contaminated grain continuously or intermittently on performance and blood parameters of backgrounding steers. Sixty black angus steers (300 ± 29.4 kg) were used in a complete randomized backgrounding (60% barley silage:40% concentrate DM basis) 84 d study. Steers were randomly assigned to 4 different treatments and housed individually. Treatments included: 1) control ration (CON; no added ergot), 2) continuous ergot mash (CEM; fed continuously at 2 ppm), 3) intermittent ergot mash (IEM; fed at 2 ppm on the first wk of each 21 d period and control diet for the remaining 2 wk), and 4) intermittent ergot pellet (IEP; fed at 2 ppm during the first wk of each 21 d period and control diet for the other 2 wk). Calves were weighed every 21 days and blood samples were collected on d 0, 42, and 84. No treatment effects (P>0.05) were observed for complete blood count. Steer DMI was reduced for all ergot diets compared to the CON diet (P< 0.01, 7.45 vs. 8.05 kg/d). Steer ADG was reduced for all ergot diets compared to the CON diet (P< 0.01). CEM fed steers had lower ADG (P< 0.01, 0.980 vs. 0.735 kg) and shrunk final weight (P< 0.01, 366 vs. 350 kg) than CON calves, but CEM and IEM were no different. CEM fed steers had lower Gain:Feed (P< 0.07, 0.130 vs. 0.142) than CON calves. Pelleting ergot contaminated grain did not reduce the impact of ergot alkaloids on any of the measured parameters. Results suggest that continuously or intermittently feeding an ergot contaminated TMR (2 ppm) can significantly reduce the growth performance of backgrounded feedlot steers but no effects were observed for blood parameters. Pelleting was not an effective method of reducing ergot toxicity.
157 Comparison of Reproductive and Early Growth Performance of an F1 Usda Prime Yield Grade one Carcass Clone Sire and an Industry-Leading Purebred Sire in the Beef x Dairy Production System
Authors: Richardson Katylyn J , Lust David G , Lawrence Ty E , Perkins Tommy L
Published: September 2022

The objectives of this research were to determine if an F1 USDA Prime, yield grade 1 sire produced from the WTAMU PrimeOne Project (Sire A) was a competitive sire for producing dairy composites when compared to a purebred Angus sire (Sire B), and to evaluate any subsequent reproductive impact of sire on dam. Dairy cows (n = 1,930) were artificially inseminated resulting in 763 pregnancies with 564 births and 536 live calves. Data was collected at a large commercial dairy and analyzed using SAS 9.4 with sire as fixed effect; lactation, breeding technician and services per conception were random effects. Individual animal was experimental unit (n = 536). Conception rates were 40% for Sire A and 31% for Sire B (P ≤ 0.01). Average gestation length (GL) was 284-d and 280-d for Sire A and B, respectively (P ≤ 0.01). Calves by Sire B reported lower average birth weight (BW) than those by Sire A (P ≤ 0.01) with no difference in calving ease score (CE) (P = 0.24). There was no difference in 60-d (P = 0.58) or 120-d calf weights (P = 0.47). However, calves by Sire B reported higher average daily gains at both 60- (0.61 and 0.58 kg; P ≤ 0.01) and 120-d (0.70 and 0.67 kg; P = 0.03). Sire had no effect on morbidity (P = 0.62) or mortality (P = 0.25). Post-partum interval (PPI) and time from first estrus to conception were not different between sires (P = 0.19; P = 0.14). BW and CE did not affect PPI or time from first estrus to conception. Data from this trial indicates the cloned progeny sire increased conception rates, but the purebred Angus sire was more favorable for GL, BW and progeny growth performance. Neither sire negatively impacted subsequent reproductive performance of the dam.
153 Phenotypic Selection of Efficient Beef Cows and Differences in Digestive Physiology
Authors: Delver Justin J , McKinnon John J , Lardner Bart , Ribeiro Gabriel O , Penner Gregory B
Published: September 2022

This study evaluated beef cows identified as having high or low efficiency when managed in extensive systems and whether they differ in terms of digestive physiology. Nine high (HE) and low efficiency (LE) cows were selected from a group of 86 Angus cows using 2 years of selection data. Yearly ranks were assessed based on three weighted criteria: cow rump fat at calving; calving interval; and calf weaning weight. The 18 cows were then ruminally cannulated and used to evaluate their response to high (HQ; 41.0±0.78% NDF), medium-high (MHQ; 56.9±1.17% NDF), moderate (MQ; 62.5±3.40% NDF), and low-quality forage (LQ; 64.3±1.40% NDF) diets using four consecutive 26-d periods where diet quality progressively decreased by period for all cows. There was no phenotype′diet interactions. Start and end BW were 48 and 45 kg less (P< 0.01) and rump fat was thicker for HE than LE cows (P=0.02). Although total DMI did not differ (13.0 kg/d; P=0.93), DMI (%BW) was greater for HE (2.12%) than LE (1.97%, P< 0.01). Ruminal pH, short-chain fatty acid concentration, and the molar proportion of acetate, butyrate, and propionate did not differ. Ruminal digesta weight was 4 kg greater (P=0.04) and the pool sizes of DM (P=0.01), NDF (P=0.03) and undigested NDF (P< 0.01) were greater for LE than HE. Ruminal NDF passage rate was greater for HE than LE cows (3.11 vs. 2.89%/h, P=0.05), but there were no differences for the rate of NDF digestion. Ruminal contraction amplitude (P=0.01) and peak area (P< 0.01) were higher for LE than HE cows. Apparent total tract nutrient digestibility did not differ (P≥0.23). Cows identified as being efficient under an extensive management system have greater DMI as a proportion of BW, less ruminal digesta weight, and greater NDF passage rate but did not differ for total tract digestibility.
162 Differential Late Gestation Metabolizable Energy Intake Alters Adipose-Specific Insulin Responsiveness in Antepartum Beef Cattle
Authors: Hare Koryn S , Croft Emily , Penner Gregory B , Wood Katharine M , Steele Michael A
Published: September 2022

We evaluated how metabolizable energy (ME) intake influences antepartum insulin sensitivity in beef cattle. Angus-Simmental cattle (primiparous: n = 17; multiparous: n = 21) were randomly assigned to treatments supplying 80 (LowME, n = 19) or 120% (HighME, n = 19) of predicted ME requirements for 53 d prepartum. At 7 d antepartum, intravenous glucose tolerance tests (IVGTT) were imposed by infusing 1.36 g glucose/kg BW0.75 and sampling from -3 to 90 min to measure plasma glucose and insulin and serum non-esterified fatty acids (NEFA) concentrations. Data were analyzed using PROC GLIMMIX with the fixed effects of treatment, parity, time (repeated), and treatment×time and considering cow(treatment) as random. Baseline glucose concentration increased (P = 0.03) and baseline insulin concentration tended to increase (P = 0.06) for HighME relative to LowME cattle irrespective (P ≥ 0.33) of parity, whereas baseline NEFA concentration was elevated (P < 0.01) for LowME vs. HighME. Plasma glucose-insulin concentrations during the IVGTT did not differ (P ≥ 0.25) by treatment, treatment×time, or parity. However, serum NEFA was elevated (P < 0.01) throughout the IVGTT for LowME vs. HighME cattle and tended to be affected (P = 0.09) by the treatment×time interaction as NEFA concentrations became similar at 90 min due to HighME cattle having a shallower (treatment×time: P < 0.01) decremental NEFA response than LowME cattle. Low ME cattle cleared NEFA more quickly (75% increase; P < 0.01) than HighME. The glucose positive incremental area-under-the-curve throughout the IVGTT tended to be lesser (P = 0.06) for heifers than cows but heifers had a blunted (P ≤ 0.05) glucose-stimulated reduction in NEFA and NEFA clearance rate compared to cows. These data demonstrate that ME provision may alter adipose insulin responsiveness in antepartum beef cattle and that heifers respond to excess glucose and NEFA differently than cows.
164 Out-of-Feed Events and Gastric Ulcers in Finishing Pigs fed 40% air-Classified pea Starch Diets
Authors: Kpogo Agbee L , Dubois Megan , Loewen Matthew , Beaulieu Denise , Newkirk Rex N
Published: September 2022

Air-classified pea starch (ACPS), a new feed ingredient, that is very fine and may contribute to bridging and the formation of gastric ulcers in pigs, especially if combined with extended feed outage event. The objective of this study was to determine the impact of a feed-out duration event in finishing pigs fed 40% ACPS diets, on gastric ulcers and animal growth parameters. A 28-d trial was performed utilizing 90 pigs with initial BW of 90.6±2.2 kg, housed in groups of 5 in a complete randomized design. A control group of pigs were also fed standard production diets without ACPS. A total of four treatments consisting of a control group (no ACPS) that had continuous access to standard feed, and an ACPS diet group exposed to 0h, 16h and 24h feed-out events. After d 28, 3 pigs/pen from the pigs fed ACPS diets were sent to a commercial abattoir and their stomach tissues harvested. Lesions in the pars oesophagea were scored on a scale of 0 to 4. Pigs fed the ACPS diets tended to have a higher BW (P < 0.09) compared to the control pigs by d 7. However, there was no difference on the overall BW (P>0.09). ADG was higher (P < 0.05) in pigs fed the ACPS diets in the initial 7 days than the control pigs. Overall ADFI in pigs fed ACPS diets were higher (P < 0.05) than the control pigs. The overall G:F was reduced in the ACPS-fed pigs. The 0h, 16h and 24h out of feed events produced 83%, 91% and 100% ulcers respectively. With the average ulcer scores being 1.8, 2.3 and 2.0 for the 0h, 16h and 24h, respectively. In conclusion, feeding 40% ACPS diets resulted in a high incidence of ulcers and 16h feed outage results in the highest severity.
174 All Things Bison: The Known and the Unknown
Authors: Galbraith Jayson
Published: September 2022

Bison (Bison bison) are a majestic species native to North America that have a rich yet turbulent history. This iconic species is valued due to its cultural significance among indigenous people, impact on the vast geography that it inhabited and commercially for its meat products with desirable attributes. Conservation efforts have included both public and privately owned herds, and efforts to increase their numbers presently continue on both fronts. The objective of this presentation is to provide some historical context about bison, an overview of bison ranching in North America, review research on bison and suggest research topics of importance for this species. Bison roamed North America from Alaska to the northern tier of Mexican states in massive numbers up until the late 1800’s where relentless hunting and waste dwindled their numbers to no more than 1500 head. Today the farmed bison industry in North America is a thriving livestock industry with over 300,000 bison on farms and a keen consumer interested in the story and sustainability of bison. The primary product from the industry is meat, but skulls, hides and farm tourism are also sources of revenue for the industry. There is much about bison that is unknown, but the body of knowledge is increasing as research is published and through code of practice development. Genetic testing and disease surveillance are important tools for species preservation, both on private ranches and public herds. Understanding bison seasonality, adaptations to low quality forages, interactions with their environment and sensitivity to stress helps both the conservation and commercial raising of bison. More research into nutrition, meat quality, reproduction, technology adoption and handling techniques to lower impacts of stress will help efforts towards successfully raising and enjoying bison.