bluuebunny/crossref_metadata_2025_split huggingface dataset:
168 Bentley Lecture: Feeding Co-Products to Pigs to Reach Sustainable Food Production and Reduce Feed Cost
Authors: Zijlstra Ruurd T , Beltranena Eduardo 
Published: October 2023

Abstract
Changes occurred in the last two pandemic years that resulted in tremendous pressures on feedstuff supply. In Canada, causes for reduced cereal, pulse, and oilseed grain supply included a failed crop harvest in Western Canada in 2021 and increased demand for plant protein for food ingredients and for plant oils for cooking and renewable diesel added further pressure. Since January 2022, COVID-associated inflationary pressures, strained supply chains, the Russian invasion of Ukraine, and speculation have increased feedstuff prices further. Grains and tubers may serve as feedstuffs but are also processed into human food, fuel, and bio-industrial products. Together with these products, feed co-products such as distillers dried grains with solubles, canola meal and expeller, wheat millrun and bran, and sugar beet pulp are produced. As omnivores, pigs are ideally suited to convert these non-human edible co-products into high quality animal protein for human consumption. Thereby, co-products can reduce reliance on human edible grains to raise pigs and partially offset increases in feed cost provided their price is less per unit of net energy or digestible lysine, but also present risks, feeding challenges, and opportunities. First, processing of co-products adds variability in macronutrient profile beyond the intrinsic variability of crops. Thus, feed quality evaluation to regularly update digestibility profiles of energy, amino acid, and phosphorus is important. Second, fermentation and heat processing impact amino acid and phosphorus availability. Overheating reduces lysine availability due to Maillard reactions, reduces heat-labile anti-nutritional factors, but combined with fermentation, may increase mineral availability. Third, co-products may possess starch and fiber characteristics that benefit gut health. Fourth, co-products may contain chemical residues and mycotoxins such as deoxynivalenol that survive or are augmented by processing that reduce voluntary feed intake. Fifth, due to their decreased digestibility, dietary inclusion of co-products generally increases excretion of organic matter, P, and N by pigs. Technologies such as tail-end processing and feed enzymes are thus required to increase nutrient digestibility. Finally, dietary inclusion of co-product may impact carcass characteristics and pork quality. For example, inclusion of high fiber co-products reduces dressing percentage and inclusion of high unsaturated fatty acid co-products softens pork fat. In conclusion, the feeding of co-products may reduce feed costs per unit of pork produced, but also provides challenges to achieve cost-effective, predictable growth performance, carcass characteristics, and pork quality. While feeding co-products remains a solution to reduce feed cost, feeding co-products in substitution of grains is now also seen as a piece of the puzzle to reach sustainable food production systems.
170 Do you Have the Energy to Grind Feed Costs and Maximize Net Income in Demanding Economic Times?
Authors: Patience John , Li Qingyun 
Published: October 2023

Abstract
Energy is not only the most expensive component of the diet, but also among the most complex. Energy impacts all aspects of the growth and metabolism of the pig. Therefore, when feed costs escalate, energy is a predictable though challenging target for increased attention. To achieve greatest success, a two-pronged approach is warranted. The first focuses on our understanding of the fundamentals of energy science and the second logically follows with applying this knowledge in practice. This presentation will address both the science and the application. Formulating energy in pig diets is a complicated process. For example, one can achieve equal dietary energy values with different proportions of protein, starch, fat and fiber. Each of these nutrients is used with a different level of efficiency by the pig, leading one to question whether equal performance should be expected just because ME or NE is the same. We will dig a bit more deeply into how energy values of ingredients are generated, what assumptions are made in this process and the limitations of these values in predicting pig performance. Beyond ME and NE, we will note that changing energy sources may also alter the microbiota, oxidative load, gut structure and function, and even the digestibility of dietary nutrients. This, in turn, can impact not only the performance of the pig, but also resistance to disease and susceptibility to environmental stress. We will also discuss why feed efficiency is sometimes highly correlated to dietary energy but in other cases, this relationship is quite weak; how can this be? On a positive note, the ME or NE of ingredients has been found to be highly correlated with certain dietary constituents. This infers that the prediction of the energy content of ingredients should be quite effective, and such predictions will improve the precision of diet formulation. Moving forward, it makes sense that wherever possible, energy response curves should be part of the toolkit available to swine nutritionists, but these curves should involve diverse diet composition, unlike the energy titration studies commonly used in our industry. When energy is the most expensive, and production margins are weakest, this is the very time to invest strategically in diet analysis to ensure that we are extracting every bit of energy we can from available ingredients. In other words, are we achieving our formulation targets? Because the topic of dietary energy is so large and complex, we will remind ourselves where we can have the greatest impact on net income by managing energy. In conclusion, energy drives feed costs and drives performance. As complex a topic as it is, we will be rewarded by understanding dietary energy more deeply, and applying that knowledge as effectively as possible in commercial practice.
169 Minimizing Sow Feeding Cost While Enhancing Production
Authors: Menegat Mariana 
Published: October 2023

Abstract
Strategies to minimize sow feeding cost while enhancing production are important to the overall success of an operation. Feed to the sow breeding herd accounts for approximately 15% of the total feed use and cost within a production system. Thus, a 10% improvement in sow feed efficiency can represent 0.05 points in feed efficiency for the whole herd. While advancements in knowledge around sow nutrition have been gradual, improvements in sow reproductive performance, productivity, and body composition have been substantial, yielding a remarkably efficient contemporary sow. In fact, efficiency may be key to the success of implementation of strategies that minimize feed cost and at the same time enhance production in the sow herd. In terms of minimizing sow feed usage, an important strategy is to implement feeding levels according to a body condition score in gestation to prevent over-feeding and an over-conditioned herd. It is also crucial to assess feeding levels to open sows, either in wean-to-estrus interval or in the open pool, to avoid feed wastage with ad libitum feeding. Regular feed boxes calibration in gestation and feeder adjustments in lactation are critical to allow an adequate feeding level to sows, while preventing feed wastage. In terms of minimizing feed cost, it is important to review the energy, lysine, and phosphorus requirements of sows on a daily intake basis and account for average herd weight. That provides the opportunity to estimate the ideal balance between nutrient density and feeding level to minimize overall feed cost. In addition, it is critical to understand the impact of energy density and bulk density on overall feed cost. As reduced energy and bulk density ingredients are incorporated into the feed, feeding levels should be increased and could potentially offset feed costs savings. In a dynamic economic landscape, the strategies summarized here may aid in the goal of finding opportunities to minimize sow feeding cost but at the same time provide nutritional support that enables sows to fully express their production potential.
103 In Utero Exposure to Maternal Heat Stress Impairs Leydig Cell Development and Function in the Boar
Authors: Nordell Nicole , Bernhard Cathy , Wegner Maddie , Metcalf Rebecca , Rupert John , Lagundžin Dragana , Sharma Kanika , Sharp Katharine , Safranski Tim J , Lucy Matt , Desaulniers Amy T 
Published: October 2023

Abstract
Due to the nearly exclusive use of artificial insemination, a typical U.S. boar sires ~8,398 progeny per year which is a 99.7% greater gene transmission rate compared with a sow (~23.1 progeny/year). Therefore, the boar has the greatest cumulative impact on swine reproductive performance and drives genetic progress in the herd. However, boar fertility is threatened by climate change. While boar studs are cooled to prevent heat stress, it is cost prohibitive to efficiently cool the six million pregnant sows that are exposed annually, leading to in utero heat stress (IUHS) of developing progeny. The IUHS of the boar reduces the number of pre-spermatogonia in neonatal testes and decimates subsequent semen quality by reducing both total sperm count (24% decrease) and increasing the proportion of abnormal sperm (42% increase). These data suggest that IUHS programs a lifetime of testis dysfunction reducing the breeding potential of boars. However, the biological mechanisms mediating this effect are undefined. The objective of this study was to determine how IUHS affects Leydig cell development and the testicular proteome. Pregnant sows were exposed to either heat stress (28 to 38°C; n = 18) or thermal neutral (17 to 22 °C; n = 18) conditions from day 27 to 57 of gestation. Neonatal boars exposed to IUHS (n = 23) or in utero thermal neutral (IUTN; n = 29) conditions were castrated at 3 days of age. Testes were preserved for histological analysis and proteomics. Leydig cells within IUHS testes were hypertrophic compared with IUTN controls (147.3 ± 1.6 µm2 versus 132.8 ± 1.4 µm2; P &lt; 0.0001). Moreover, IUHS decreased the number of Leydig cells (Per microscopy field) compared with IUTN males (72.7 ± 2.0 Leydig cells/field versus 93.5 ± 1.8 Leydig cells/field). The testicular proteome was interrogated in a subset of animals (n = 8/treatment). A total of 519 proteins (32% of those detected) were differentially abundant between IUHS and IUTN testes (278 proteins down-regulated, 241 proteins up-regulated) including proteins important for Sertoli (e.g., insulin-like growth factor binding protein), Leydig (e.g., CYP19), and germ (e.g., glyceraldehyde 3-phosphate dehydrogenase) cell function. Notably, gene ontology analysis revealed that both steroid & cholesterol biosynthesis pathways were enriched (P &lt; 0.0001) indicating differential expression of proteins needed for testicular steroidogenesis. Notably, CYP19 (enzyme expressed in porcine Leydig cells that converts testosterone to 17β-estradiol) was down-regulated in IUHS testes. Therefore, these data suggest that IUHS leads to Leydig cell dysfunction in boars. The importance of Leydig cells to male reproduction is unequivocal; thus, IUHS represents a mounting threat to male fertility, especially in the face of climate change.
21 Intentionally Induced Barrier Dysfunction Causes Inflammation, Decreases Growth, and Alters Carcass Characteristics of Feedlot Cattle
Authors: Schoonmaker Jon P 
Published: October 2023

Abstract
There are a variety of acute and chronic psychological and physical stressors associated with management practices used in beef production systems. Primary challenges in feedlot cattle include heat stress, acute and subacute acidosis, weaning, transportation, feed deprivation/restriction, and social mixing/crowding. These stressors disturb the homeostatic state of the host and microbiome and cause acute or chronic inflammation resulting in damage to the gastrointestinal tract (GIT) epithelial barrier that leaves the animal vulnerable to enteric pathogens and toxins. A breach of the small intestinal barrier (leaky gut) allows unwanted pathogens and toxins to infiltrate into blood, causing infection, depressed feed intake, and diverts nutritional resources away from anabolic processes. We have demonstrated that intentionally inducing GIT inflammation in feedlot cattle with aspirin, which is known to cause mucosal injury and increase GIT barrier dysfunction, provides a model system to better understand the metabolic cost of leaky gut in grain-fed feedlot cattle. Indeed, aspirin increased leakage of chromium-EDTA into urine, raised serum concentrations of lipopolysaccharide binding protein (LBP), decreased growth by 4.5 to 8.5%, and re-partitioned carcass components from lean tissue (rib-eye area) into fat. Thus, the chronic inflammatory effects of leaky gut have the potential to create a significant economic loss. Our work also shows that in-feed administration of monensin and tylosin have offered a solution to the non-specific immune response observed in grain-fed cattle by increasing jejunal villus height to crypt depth ratio, diminishing leaky gut, and decreasing serum LBP. Finally, we have observed that molasses based liquid supplements increase ruminal butyrate concentration, resulting in improved gut barrier function, decreased serum inflammatory markers, and greater DMI and ADG in newly received feedlot cattle fed a 30% roughage diet.
25 Measuring Intestinal Permeability When Urine is not an Option
Authors: Koltes Dawn A , Wiersema Maddison , Kerr Brian J 
Published: October 2023

Abstract
The need to understand intestinal health is of increasing importance as the livestock industry seeks to maintain performance efficiency while eliminating prophylactic antibiotic usage. Intestinal permeability is a biomarker of intestinal health as it measures the movement of an indigestible marker across the intestinal barrier with excretion in the urine as the primary biological specimen collected for measurement. The adoption of these methods into poultry has been slow due to the lack of urine excretion. Therefore, the objective of this study is to compare differences in intestinal permeability assays in serum of poultry to determine if these assays could be a reliable method to detect changes in intestinal permeability in poultry under a known stressor. To compare the two commonly used methods [fluorescein isothiocyanate-dextran (FITC-D) method and lactulose/mannitol (LMS) dual sugar method], 2 independent trials were conducted with 40 pens split across 2 fed status (fed or fasted for 12 hours) and 4 sugar treatments (no sugar, FITC-D, LMS, FITC-D+LMS). All pens were sampled at 3 timepoints (14, 28, and 42 days of age) with 5 birds sampled per timepoint. Serum FITC-D was determined through fluorescent spectrophotometry, while mannitol and lactulose concentrations were determined using ion chromatography. Data were analyzed using PROC Glimmix. Fed status, sugar treatment, age, and all 2-and 3-way interactions were included as fixed effects. Trial was included in the model as a random effect with pen included as a repeated effect. Serum lactulose and FITC-D increased in fasted compared with fed birds (P &lt; 0.006). Surprisingly, mannitol, which was expected to be similar across fed and fasted, was increased in fed compared with fasted birds (P &lt; 0.001). The increased concentrations of mannitol in fed birds and measurable concentrations of mannitol in birds not given mannitol suggest another molecule eluted at the same rate as mannitol. Therefore, we propose under these conditions that mannitol, and its ratio with lactulose, are not appropriate methods for measuring intestinal permeability in poultry. Lactulose and FITC-D were increased in serum when the birds were provided those sugars and serum concentration of both sugars decreased at 28 days compared with 14 and 42 days (P &lt; 0.003). FITC-D had a significant 2-way interaction for the sugar by fed status (P &lt; 0.05) whereas other 2-and 3-way interactions were similar across treatments (P &gt; 0.202). Serum lactulose concentrations were affected by all 2-and 3-way interactions with elevated serum lactulose concentrations in broilers provided lactulose and fasted (P &lt; 0.001). Birds that did not receive lactulose had very low to undetectable concentrations of lactulose. This reduced background noise for the detection of serum lactulose and the ability statistically to detect small changes in intestinal permeability make lactulose a potential serum biomarker for intestinal permeability in poultry.
163 Effect of Enogen Feed Corn Inclusion in Conventional and Natural Finishing Cattle Diets
Authors: Miller Jessica L , Wilke Karla , Erickson Galen E , Loza Pablo L 
Published: October 2023

Abstract
A finishing experiment was conducted to determine the effects of Enogen Feed Corn inclusion in comparison with a control corn hybrid within natural and conventional feeding programs on finishing performance. The experiment used 400 crossbred steers (initial BW = 384 ± 33 kg) and 200 crossbred heifers (initial BW = 330 ± 19 kg) in a 2×2 factorial arrangement of treatments with 10 replications of steers and 5 replications of heifers per treatment. Factors were Enogen Feed Corn (EFC) or control corn hybrid inclusion as dry-rolled corn and corn silage within conventional and natural feeding programs. Cattle assigned to the conventional program were fed rations that contained feed additives and received implants whereas cattle in the natural program received neither. Performance data were analyzed as a 2×2×2 factorial assessing interactions between sex, feeding program, and corn hybrid inclusion. A sex by feeding program by corn hybrid (P = 0.01) interaction was observed for dry matter intake (DMI). Interactions between sex and feeding program were observed for carcass adjusted final BW (final BW; P &lt; 0.01), average daily gain (ADG; P &lt; 0.01), feed efficiency (G:F; P &lt; 0.01), and hot carcass weight (HCW; P = 0.01). No significant corn hybrid by sex interactions (P ≥ 0.12) or corn hybrid by feeding program interactions (P ≥ 0.13) were observed. Inclusion of EFC in natural heifer diets tended to increase DMI by 0.4 kg/d (P = 0.10), while hybrid inclusion had no impact on DMI of conventional heifers. Feeding EFC in conventional steer diets tended to increase DMI by 0.4 kg/d (P = 0.06) compared with steers consuming the control corn hybrid diet. Corn hybrid had no impact on DMI in natural steer diets (P = 0.15). Carcass adjusted final BW decreased by 75 kg in natural steers and 41 kg in natural heifers compared with conventional programs (P &lt; 0.01). Natural heifers gained 0.24 kg/d less than conventional heifers (P &lt; 0.01). Feeding steers in the natural program reduced ADG by 0.43 kg/d in comparison with conventional program steers (P &lt; 0.01). Compared with natural cattle, G:F improved by 13.0% when heifers were fed in a conventional program (P &lt; 0.01) and 19.4% when steers were fed in a conventional program (P &lt; 0.01). Feeding program had no effect on marbling (P = 0.38) while conventional cattle had greater 12th rib fat than natural cattle (P &lt; 0.01). Inclusion of EFC had no effect on ADG (P = 0.71), G:F (P = 0.22), or HCW (P = 0.57). The incorporation of implants and feed additives within the finishing period increased final BW, HCW, and ADG leading to improved G:F in steers and heifers, with the improvement being greater in steers.
164 Effect of Processing Method of Hybrid rye on Growth Performance, Efficiency of Dietary net Energy Utilization, and Carcass Characteristics of Yearling Steers fed a Finishing Diet
Authors: Ross Cassidy , Bird Scott , Smith Zachary K , Rusche Warren C 
Published: October 2023

Abstract
Predominantly Angus steers were used in a 147-day randomized complete block design experiment (RCBD) to evaluate the effects of rye processing method on growth performance, feed efficiency, and carcass characteristics. Steers [n = 192, initial body weight (BW) = 410 ± 20.9 kg] were individually weighed and allotted to 1 of 24 pens (n = 8 steers/pen; 6 pens/treatment). Four treatments were used where hybrid rye grain (total ergot alkaloid concentration = 1,007 ppb, DM basis) was processed using three different methods [unprocessed (UP); dry-rolled (DR); or hammer-milled (HM)] fed at 17% of diet DM along with 43% dry-rolled corn (DRC) compared with a control diet containing 60% DRC on a DM basis (CON). Data were analyzed as an RCBD using the GLIMMIX procedure of SAS with treatment as the fixed effect and block (Pen location) as the random effect; pen was the experimental unit. No differences (P ≥ 0.44) were observed among treatments for live final BW or average daily gain (ADG). Dry matter intake (DMI) was greater for HM (12.27 kg) compared with CON and DR (11.84 and 11.48 kg, respectively) with DR having 4.9% less DMI compared with UP (P = 0.01; SEM = 0.200). UP and HM treatments tended to have 4.8% poorer G:F compared with CON and DR (P = 0.07). Dietary treatments did not affect carcass traits, percent empty body fatness (EBF), or final BW at 28% EBF (P ≥ 0.23). Distributions of USDA Quality or Yield grades were unaffected by treatment (P ≥ 0.23), nor was the incidence or severity of liver abscesses (P = 0.25). Estimated NEm and NEg values of the diet for UP (1.90 and 1.26 Mcal/kg, respectively) were reduced compared with CON and DR (1.98 and 1.32 Mcal/kg, respectively), with HM intermediate (P = 0.05, SEM = 0.033 and 0.029 for NEm and NEg, respectively). Net energy values for UP and HM rye were within 7% of current feeding standards when calculated using the substitution method. Rolling increased apparent ingredient NEg for rye by 30.1% compared with UP or HM rye. Processing rye grain by dry-rolling increased dietary net energy values and tended to improve gain efficiency compared with not processing or using a hammer mill. Rye grain can be partially substituted for DRC with negligible impact on growth performance or carcass measures.
266 Comparing the Prediction Accuracy of Models for Estimating DMI of Beef Heifers Using Surface Area, Volume, Body Measurements or Body Weight by the Elastic net Regularized Regression Method
Authors: Yusuf Mustapha , Mosher Macie K , Fontoura Ananda B P , Hanna Lauren L Hulsman , Bauer Marc L , Ringwall Kris A , Swanson Kendall C 
Published: October 2023

Abstract
Dry matter intake (DMI) remains one of the most variable and significant factors contributing to cost of production in cow-calf systems. Body weight (BW) has been used to estimate DMI of individual cattle as an alternative to measuring DMI, which is expensive, labor intensive, and not practically feasible in production environments. The objective of this study was to evaluate if calculated body measurements [volume (VL) 218 to 503 liters; frame score (FS) 2.1 to 7.5; surface area (SA) 4.02 to 7.12 m2) and direct body measurements (DBM: body length (BL) 89 to 136 cm; hip height (HH) 96 to 136 cm; hip width (HW) 33 to 52 cm; heart girth (HG) 149 to 191 cm; mid girth (MG) 177 to 234 cm; and flank girth (FG) 156 to 239 cm] could be used to estimate DMI of heifers as accurately as using BW (267 to 506 kg). Data from 300 heifers (9 breeds) collected over 4 years were used. Year was included in the model as a random effect. An elastic net model using the glmnet function of the R caret package was used. There were 206 training and 94 testing observations. The models were cross validated 10-fold with 5 repetitions. Models with the least minimum root mean square error and greatest median R-square (R2) values were selected as the best models. Model R2 ranged from 0.19 (SA) to 0.63 (BW), where DBM (0.40) and FS (0.43) performed similarly. As prior studies have suggested, BW in this study accounts for the greatest variation in DMI. However, calculated FS and ABM also explained some variation in DMI and more so than VL (0.22) and SA. These data indicate that FS and ABM could be used as alternatives in cases where BW records are not available to estimate DMI of heifers.