bluuebunny/crossref_metadata_2025 huggingface dataset:
298 Comparison of Amino Acid Digestibility in Pulses Between Broiler Chickens and Pigs
Authors: Adekoya Abidemi A , Adeola Olayiwola
Published: October 2023

The difference in capacity and structure of the gastrointestinal tract of broiler chickens and pigs could influence the digestibility of amino acids (AA) in feed ingredients. Therefore, two experiments were carried out to compare the standardized ileal digestibility (SID) of AA in faba beans (FB) and three field peas (FP) cultivars between broiler chickens (Exp.1) and pigs (Exp.2). Four diets were prepared to contain FB, FP DS-Admiral (FPD), FP Hampton (FPH), or FP 4010 (FP4) as the sole source of nitrogen. A nitrogen-free diet (NFD) was also prepared to estimate the basal endogenous losses of AA. On day 21 post-hatch, 416 male broiler chickens with an initial body weight (BW) of 951 ± 111 g were allotted to 5 diets in a randomized complete block design with BW as a blocking factor in Exp.1. There were 8 replicate cages with 10 birds per cage for diets containing the test ingredients and 12 birds per cage for the NFD. All birds were fed the diets for 5 days. On day 26 post-hatch, birds were euthanized by CO2 asphyxiation and digesta contents from the distal two-thirds of the ileum were collected. Barrows (n = 20) with an initial BW of 30.2 ± 1.58 kg, surgically fitted with T-cannulas at the distal ileum, were used in Exp.2. The pigs were divided into 4 blocks based on BW and assigned to a 5 × 2 incomplete Latin Square design consisting of 5 dietary treatments and 2 experimental periods. The daily feeding allowance was calculated at 4% of the mean BW of the pigs in each block. The adaptation period was 5 days, followed by a 2-day collection of ileal digesta samples. Data from Exp.1 and 2 were pooled and analyzed as a 2 × 4 factorial treatment arrangement with the effect of species and test ingredients. There were no interactions (P > 0.05) between diet and species. For broiler chickens, the SID of Lys in FB, FPD, FPH, and FP4 were 91.3, 91.0, 92.5, and 85.1%, respectively, whereas for pigs the SID of Lys were 82.4, 85.7, 87.0, and 78.9%, respectively. The respective SID of Met in FB, FPD, FPH, and FP4 were 84.1, 87.3, 89.8, and 72.1% for broiler chickens. Furthermore, the SID of Met in FB, FPD, FPH, and FP4 for pigs were 71.5, 80.4, 81.8, and 68.1%, respectively. Field peas 4010 had significantly less (P < 0.05) SID of indispensable AA compared with the other ingredients, except for the SID of Trp. In conclusion, the SID of AA were significantly greater (P < 0.05) in broiler chickens compared with pigs, except for the greater (P < 0.05) SID of Pro in pigs and similar SID of Arg between both species.
87 Improving Pig Livability Before, During, and After Parturition
Authors: Zhao Junmei , Faris Richard , Hu Qiong , Vanderhaeghe Caroline , Goris Kaat , Aumiller Tobias
Published: October 2023

Nearly a quarter of piglets are lost from farrowing to weaning, with stillbirths representing about 7.5% and preweaning mortality contributing another 15.7% in North America (Pigchamp, Metafarm). This averages to a loss of 7.37 pigs per sow per year resulting in significant economic loss and animal welfare concerns. Main contributors of low piglet survivability include poor sow body condition at farrowing, long farrowing duration, piglet asphyxiation, insufficient colostrum consumption, and health challenges. Piglet livability can be improved through nutrition and management solutions before, during, and after parturition. In this context three main strategies have been shown to be effective: 1) managing sow body composition, 2) improving fetal oxygen and nutrient supply via the nitric oxide pathway, and 3) improving piglet health through functional ingredients in the diet of the sow. Highly prolific sows (> 16 born alive) lose both backfat and muscle during the later stages of gestation. Additionally, loin depth loss is more detrimental for piglet survival compared with backfat loss. Sows with the highest stillborn (> 2 per litter) lose the most loin muscle depth regardless of genetics. A solution to reduce this effect and improve piglet survivability is a two-phase gestation feeding with more amino acids in late gestation. Average farrowing duration of a highly prolific sow is 300 minutes and increasing with larger litters. To make things worse, most sows are going through farrowing without food and/or drink. Nutrients and energy supply to sow are critical for shorting farrowing duration and piglet survivability. Compared with pigs that died before weaning, surviving pigs at weaning have greater blood oxygen and less carbon dioxide and lactate at birth. Nitric oxide boosting technologies have been used widely to enhance athletic performance and increase endurance. This vasodilative effect of nitric oxide can be used similarly in sows to increased placental blood flow and thus oxygen and nutrient supply to fetuses. This reduces the risk of asphyxiation and therefore can increase piglet vitality at birth and decreases stillbirth and pre-weaning mortality. Post-parturition health challenge poses a large risk to piglet survivability. Functional feed ingredients, such as botanicals, are a potential solution to improve piglet health and resilience to challenging conditions. Some botanicals can pass through placenta and milk to supply piglets. Milk from sows fed specific botanicals has been shown to improve inhibitory activity against Bacillus subtilis and Staphylococcus aureus. Some specific botanicals can improve sow and piglet antioxidant status, and piglet gut health. In conclusion, managing sow body condition, nitric oxide pathway stimulation, and functional sow diets are effective ways to improve piglet survivability in challenging environments.
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

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

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

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

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 < 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 < 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

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

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 < 0.006). Surprisingly, mannitol, which was expected to be similar across fed and fasted, was increased in fed compared with fasted birds (P < 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 < 0.003). FITC-D had a significant 2-way interaction for the sugar by fed status (P < 0.05) whereas other 2-and 3-way interactions were similar across treatments (P > 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 < 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

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 < 0.01), average daily gain (ADG; P < 0.01), feed efficiency (G:F; P < 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 < 0.01). Natural heifers gained 0.24 kg/d less than conventional heifers (P < 0.01). Feeding steers in the natural program reduced ADG by 0.43 kg/d in comparison with conventional program steers (P < 0.01). Compared with natural cattle, G:F improved by 13.0% when heifers were fed in a conventional program (P < 0.01) and 19.4% when steers were fed in a conventional program (P < 0.01). Feeding program had no effect on marbling (P = 0.38) while conventional cattle had greater 12th rib fat than natural cattle (P < 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

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

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.
261 Effect of Alga 1.0 on Reducing Enteric Methane Emissions from Cattle
Authors: Colin Reba L , Buse Kassidy K , Watson Andrea K , Erickson Galen E , Kononoff Paul J
Published: October 2023

Alga 1.0, an algae-derived product was used to evaluate the effect of inclusion on methane (CH4) and carbon dioxide (CO2) emissions from cattle along with diet digestibility. Twelve non-lactating, non-pregnant Jersey cows were used in 4 replicated 3x3 Latin squares. Cows were blocked by intake and assigned randomly to three treatments. Three periods were utilized with each period being 21 days long. Three treatments were evaluated with 0, 69, and 103 grams per day Alga 1.0, fed as a top dress with modified distillers grains plus solubles (MDGS) as a carrier in a corn-based diet. Diet consisted of 60% dry-rolled corn, 20% corn silage, 15% MDGS, and 5% supplement. Headbox-style indirect calorimeters were utilized to evaluate gas production from individual cows with 2 non-consecutive 23-h collections in each period. Diet digestibility was measured using complete fecal collection the last 4 days of each period. Data were analyzed with GLIMMIX procedure of SAS with cow within period as experimental unit, cow and period as random effects, and treatment as fixed effect. Alga 1.0 inclusion decreased CH4 production measured as g/d (P < 0.01) and g/kg DMI (P < 0.01). A 39% percent reduction in CH4 was expressed as g/kg of DMI with 69 g inclusion; and a 63% reduction (g/kg DMI) with 103 g inclusion of Alga 1.0. Average eructated CH4 was 17.5 g/kg of DMI, 10.7 g/kg of DMI, and 6.4 g/kg of DMI, for the control, 69 g, and 103 g treatments, respectively. Emissions of CH4 reported as g/d were 164.9 for the control diet and decreased to 88.2 g/d for 69 g inclusion and 44.4 g/d for 103 g inclusion. Emissions of CO2 as g/d tended (P = 0.08) to be less for cattle receiving 103 g of Alga 1.0; but did not differ when calculated as g/kg of DMI (P = 0.39). Oxygen consumption (O2) amounts did not differ between treatments for g/day (P = 0.26) and g/kg DMI (P = 0.39). Respiratory quotient (RQ) was not significantly impacted (P = 0.32) by treatments. Alga 1.0 inclusion did influence organic matter (OM) intake (P = 0.01) with a 0.98 kg/d decrease with 69 g inclusion and a 1.27 kg/d decrease with 103 g inclusion compared with the control. Digestibility of OM was not influenced (P = 0.89) by the inclusion of Alga 1.0 and averaged 74.9%. Digestible Energy expressed as Mcal/kg did not differ (P = 0.67) between treatments. Feeding Alga 1.0 decreased OMI but did not affect digestibility. Alga 1.0 inclusion reduced CH4 emissions from cattle compared with a dry rolled corn control diet with no significant impact on CO2 emissions.
262 Evaluation of a Single Growing-Finishing Diet for Single Source, pre-Conditioned Beef Steers of Lighter (273 kg) and Heavier (356 kg) Initial Body Weight (BW)
Authors: Norman Tommy , Ribeiro Thiago Maia , Francis Forest L , Gubbels Erin R , Hanson Santana , Grimes Becca , Rusche Warren C , Smith Zachary K
Published: October 2023

The objective of the study was to determine the influence that initial BW has on growth performance responses, efficiency of dietary net energy (NE) utilization, and carcass traits in feedlot steers. Crossbred Charolais steers from a single source, (n = 70; initial BW = 329 ± 72.6 kg) were used in feedlot experiment at the Ruminant Nutrition Center, in Brookings, SD, during a 209-day growing-finishing period. These steers represented the lightest and heaviest proportions of steers taken from a larger group of 265 steer calves. On d 0 and d 1 BW and hip height (HH) measurements were collected for allotment proposes, and the initial experimental BW was the average between d 0 and d 1 BW. Steers were allocated to 1 of 2 treatments: 1) lighter (276 ± 16 kg; LIW) or 2) heavier (356 ± 16 kg; HIW) initial BW and allotted to 10 pens (n = 7 steers/pen; 5 pens/treatment). Steers were fed a diet containing 16% roughage once daily. Data were analyzed as a randomized complete block design with pen as the experimental unit. Treatment was included as a fixed effect and block (location) was considered a random effect in the statistical model. The LIW steers had a greater cumulative HH change compared with HIW. Final BW and carcass-adjusted (HCW/0.625) BW were greater for HIW steers by 13.1% and 13.4% respectively (P ≤ 0.01). The HIW steers had a 14.4% greater DMI (P = 0.01) compared with LIW. Cumulative ADG was greater for HIW by 3% (P = 0.04). LIW steers had improved feed conversion (P = 0.01) by 11.3% compared with HIW. The HIW steers had greater (P < 0.05) HCW (15.5%), marbling scores (6.8%), and Yield grade (16.0%), and decreased REA/HCW (P = 0.01) by 5.9% compared with LIW. Steers from HIW tended to have greater rib fat (P = 0.09) by 15% compared with LIW. The distribution of USDA Yield grade was altered by initial BW (P = 0.04) with a shift in proportions of steers with greater numerical Yield grades for steers in HIW compared with LIW. No differences were detected (P ³ 0.22) for the distribution of Quality grade or liver abscess prevalence and severity. In conclusion, HIW steers had greater growth, but poorer feed efficiency compared with LIW steers. Steers with a HIW produced fatter carcasses with a greater amount of marbling.
312 Evaluation of Dietary Roughage Manipulation During the Feeding of Ractopamine Hydrochloride as a Method to Improve Ruminal Health and Control Liver Abscess Severity in Feedlot Steers
Authors: Francis Forest L , Gubbels Erin R , Hanson Santana , Norman Thomas , Ribeiro Thiago Lauro Maia , Rusche Warren C , Smith Zachary K
Published: October 2023

The objective of this study was to determine if additional roughage inclusion to feedlot steer finishing diets during the feeding of ractopamine hydrochloride (RH) is an effective method to improve rumen health and control liver abscess severity. Steers [n = 64; initial shrunk body weight (SBW) = 633 kg ± 35.1 kg] were sourced from an unrelated trial and remained in their previous study pens; pens (n = 8) were assigned to dietary treatment in a completely randomized design. All steers on trial were fed a common 7% [dry matter (DM) basis] roughage equivalent (RE) finishing diet composed of dry-rolled corn, dried distillers grains plus solubles, corn silage, and grass hay for the 58 d preceding study initiation. Steers were fitted with rumination tags to track daily rumination. Dietary treatments were CON: no diet change; and 12R: 5% (DM basis) RE addition to diet via grass hay during the feeding of RH. Steers were fed RH (300 mg/steer/d), finished on treatment diets for 28 d, and harvested at a commercial beef processor. Growth performance, efficiency of dietary net energy (NE) utilization, and continuous carcass data were analyzed with pen as the experimental unit (EU) and fixed effect of treatment. Minutes ruminating was analyzed as an analysis of covariance with individual animal as the EU, fixed effects of treatment, days on feed (DOF) and their interaction, and baseline minutes ruminating as a covariate in the model. Liver abscess prevalence, rumen health, and categorical carcass data were analyzed with the Fisher’s exact test to determine differences between treatments. No difference (P ≥ 0.19) was observed for final SBW, average daily gain, dry matter intake, feed conversion efficiency, dressing percentage, hot carcass weight, calculated yield grade, marbling score, 12th rib fat thickness, calculated empty body fat, observed dietary NE for maintenance and gain, observed-to-expected dietary NE for maintenance and gain, or distribution of liver abscess prevalence, ruminitis score, or USDA yield grade. Ribeye area tended (P = 0.10) to differ between treatments with 12R steers exhibiting a 3.5% larger ribeye. Distribution of USDA quality grade differed (P = 0.003) between treatments with 12R steers having 25% more carcasses grading USDA average choice or better. A treatment × DOF interaction (P = 0.045) was observed for minutes ruminating per day. Daily minutes ruminating was increased (P ≤ 0.05) for 12R on d 1, 2, and 20 and tended to be increased (P ≤ 0.10) for 12R on days 10, 13, 24, and 25. Inclusion of an additional 5% RE to finishing cattle diets during a 28 d RH feeding period can be a management strategy to decrease risk of digestive upsets without sacrificing growth performance or carcass quality.
311 Evaluation of Rumen Protected B-Vitamin Blend on Finishing Steer Growth Performance, Efficiency of Dietary net Energy Utilization, Carcass Trait Responses, and Liver Abscess Prevalence and Severity
Authors: Ribeiro Thiago Lauro Maia , Gubbels Erin R , Francis Forest L , Heldt Jeff S , Hanson Santana , Norman Thomas , Rusche Warren C , Smith Zachary K
Published: October 2023

The objective of this study was to determine the influence that a rumen-protected B-vitamin (RPBV) blend (containing pantothenic acid, pyridoxine, folic acid, biotin, and cyanocobalamin; Vivalto, Trouw Nutrition, Isola Vicentina, Italy) had on growth performance, efficiency of dietary net energy utilization, carcass trait responses, and liver abscess severity and prevalence in beef steers fed a finishing diet. Steers (n = 246; initial shrunk body weight (BW) = 411 ± 25.8 kg) from two sources, were used in a 126-d randomized complete block design experiment. Within 48 h after arrival, steers were individually weighed and allotted to one of 24 pens (n = 10 to 12 steers; 8 pens/treatment) and randomly assigned to 1 of 3 treatments: 1) No RPBV; 2) RPBV1 at 1 g/hd/d; 3) RPBV2 at 2 g∙animal-1∙d-1/. During the first 14 d cattle received two transition diets. From d 15 to d 126 cattle were fed the final diet containing 53% dry-rolled corn; 23% corn silage; 20% MDGS; and 4% suspended supplement. Data were analyzed using the GLIMMIX procedure of SAS 9.4 with treatment as the fixed effect and block (Pen location) as the random effect; pen was considered the experimental unit. No differences (P ≥ 0.13) were found for dry matter intake, final live BW, average daily gain (ADG), or feed efficiency (G:F) among treatments. Carcass-adjusted final BW, ADG, and G:F were not influenced by treatment (P ≥ 0.59). Hot carcass weight, dressing percentage, marbling score, kidney-pelvic-heart fat, or BW at 28% empty body fat did not differ among treatments (P ≥ 0.11). Rib eye area (REA) was altered (quadratic effect, P = 0.02) by treatment; steers from RPBV 1g had decreased REA compared with others. Additionally, calculated yield grade (YG) and calculated retail yield (RY) were altered (quadratic effect, P ≤ 0.01) by treatment; steers from RPBV 1 g had increased YG and decreased RY compared with others. Estimated empty body fatness tended (P = 0.06) to be greater from steers fed RPBV compared with control. Overall USDA YG distribution was altered by dietary treatment (P = 0.01). The proportions of YG1 and YG5 carcasses were unaffected by treatment, but there was a shift in the proportion of carcasses that graded YG2, YG3, and YG4 among treatments. Distribution of USDA Quality Grade was not altered by treatment (P = 0.53). No differences were observed on liver abscesses among treatments. The use of RPBV altered carcass muscularity and rib fat accumulation which impacted the overall YG distribution. However, RPBV did not appreciably influence any cumulative growth performance measures liver abscess incidence or severity.
202 Evaluation of Increasing Levels of Mycotoxin-Containing Corn Fines fed to Nursery Pigs on Growth Performance
Authors: Paczosa Duncan B , Chevalier Tyler B , Zheng Lan , Berry Frank , Lindemann Merlin D
Published: October 2023

The effects of feeding corn fines (screenings) containing mycotoxin levels at greater than the FDA cautionary levels were evaluated using crossbred pigs [n = 150, 90 barrows and 60 gilts; mean initial body weight (BW) = 6.42 ± 0.06 kg; n =] that were blocked by BW and sex, randomly allotted within block to 6 dietary treatments, and housed 5 pigs/pen resulting in a total of 5 replicates. The corn fines used in this study contained mycotoxin levels that were analyzed to be 20,334 ppb total fumonisin, 1,499 ppb zearalenone, and 5,075 ppb total deoxynivalenol. The corn fines were added into a corn-soybean meal basal diet at 0, 20, 40, and 60% total dietary corn fines (Diets 1-4, respectively). Diet 5 was created by adding 40 ppm of boron (as sodium tetraborate decahydrate, 11.34% B) to Diet 4. Diet 6 was created by adding 0.25% Biofix Plus with FUMzyme (DSM Nutritional Products, Parsippany, NJ) to Diet 4. Dietary treatments were fed for a total of 6 weeks; thereafter, all pigs received a common corn-soybean meal basal diet without fines for about 2 weeks. Data were analyzed by ANOVA using the GLM procedure of SAS with the pen being the experimental unit. Orthogonal polynomial contrasts were used to determine linear and quadratic effects with increasing dietary levels of corn fines in Diets 1-4 as well as preplanned single degree of freedom comparisons. Increasing fines linearly decreased ADG during week 1-6 (P = 0.03), as well as linearly decreased gain/feed ratio during week 1-6 (P = 0.04; Table 1). Comparing Diets 4 and 5 to Diet 1 during week 1-6, there was a decrease in ADG and gain/feed ratio (P < 0.05) but no effect on ADFI (P > 0.05); subsequently, the difference in Diets 4 and 5 compared with Diet 1 was no longer significant for week 1-8. Comparing Diet 6 to Diets 1 and 4 during week 1-6, pigs fed Diet 6 were able to recover 57% of the lost ADG and 30% of the lost BW gain/feed ratio that occurred when corn fines were increased from 0 to 60%. During week 6-8 (all pigs on a common diet), pigs on Diet 5 and 6 had an increase in ADG compared with Diet 1. In conclusion, as mycotoxins increased pigs exhibited negative effects on ADG and gain/feed ratio but the enzyme FUMzyme ameliorated a portion of these effects. Further, the recovery from week 6-8 from all pigs does show the importance of feeding clean corn to optimize ADG, ADFI and gain/feed ratio.
205 Relationship of Resiliency to Weaning Stress with Growth, Carcass, and Meat Quality Traits in Pigs
Authors: Luttman Andrea M , Schmidt Grace E , Raney Nancy E , Steibel Juan P , Ernst Catherine W
Published: October 2023

Acute stress before slaughter has been demonstrated to have a detrimental impact on pork quality, but little is known about whether early life stress has a similar effect. Our objective was to identify if stress resiliency or vulnerability at weaning had an impact on long-term performance resulting in differences in growth, carcass, or meat quality traits. At weaning, blood samples were collected from all gilt piglets from 26 crossbred litters (n = 170) at -1 d, 0 d, and +4 d pre- and post-weaning. For each litter, serum cortisol was used to identify the gilt most capable of returning to baseline levels by +4 d as stress resilient (SR, n = 26) and the gilt least capable as stress vulnerable (SV, n = 26). The SR and SV gilts were processed at the Michigan State University Meat Laboratory and carcass and meat quality data were collected. Carcass traits included finished live weight, hot carcass weight, dressing percentage, loin muscle area, and 10th-rib backfat depth. Meat quality traits included 45-min and ultimate pH, marbling score, subjective color score, Minolta colorimeter L*, a* and b*, and drip loss. Data were analyzed using Gaussian linear models. The base model included stress group and farrowing group as fixed effects and age at slaughter as a covariate. The SR gilts showed decreased ADG at the grow-finish stage resulting in lighter finished weight (P = 0.089 and P = 0.070, respectively). The SR gilts also had a lighter hot carcass weight (P = 0.05); however, no differences were observed in dressing percentage ( P= 0.924). the SR and SV gilts did not differ in backfat depth, but SR gilts had smaller loin muscle area (P = 0.019). No differences were observed in any of the meat quality measures. In summary, we found resiliency to weaning stress to have a minimal impact on carcass merit or meat quality. Future studies will aim to determine if the observed difference in loin muscle area is associated with gene expression differences.
204 Effects of Feeding Cellutein to Pigs at Various Concentrations from Weaning Through Finishing
Authors: Vaughn Mathew A , Barnas Mike , McNaughton James L , Gonzalez John M
Published: October 2023

The study objective was to evaluate the effects of celluTEIN (CT) on growth performance and feed efficiency during nursery and grow-finish phases. Barrows (n = 96; average BW 7.5 kg) were assigned to 32 pens with 3 pigs per pen. Pens were randomly assigned to one of four treatments: 0 ppm CT throughout (CON), 175 ppm CT during the nursery (TRT2), 100 ppm CT during grow-finish (TRT3), and 175 ppm CT during nursery and 100 ppm CT during grow-finish (TRT4) phases. The nursery phase consisted of trial day 0 to 42 and grow-finish was trial day 43 to 119. There were no treatment effects on d 0 BW and nursery feed consumption (FC; P > 0.05), but there were effects on d 42 BW, and nursery average daily gain (ADG), and feed conversion ratio (FCR; P < 0.05). Pigs in TRT2 and 4 did not differ ( P> 0.05) in BW, ADG, and FCR, but had greater measures than pigs in the other two treatments (P < 0.05). Treatment affected all measures in the grow-finish phase (P < 0.05). Control pig d 119 BW was less than all other treatment pigs (P < 0.05), TRT4 pigs had greater BW than TRT2 and 3 (P < 0.05), who did not differ (P > 0.05). All treatments had different ADG, with TRT4 being the greatest followed by TRT3, TRT2, and CON (P < 0.05). Pigs in TRT4 had greater FC than pigs in all other treatments (P < 0.05), who did not differ (P > 0.05). Control pigs had greater FCR than pigs in all other treatments (P < 0.05), who did not differ (P > 0.05). Throughout the entire 119-day study, treatment affected all measures (P < 0.05), except FC (P > 0.05). Control pig ADG was less than all other treatment pigs (P < 0.05), TRT4 pigs had greater ADG than TRT3 and 4 (P < 0.05), who did not differ (P > 0.05). All treatments had different FCR, with TRT4 being was the least followed by TRT3, TRT2, and CON (P < 0.05). These data illustrate pig performance improved when CT was supplemented in either the nursery or the finisher. The greatest feed efficiency and gain benefit was observed when CT was supplemented during both phases.