bluuebunny/crossref_metadata_2025_split huggingface dataset:
232 Evaluation of a phytogenic feed additive with essential oils and plant extracts on growth performance in single sourced steer calves fed a forage-based diet during the initial 53 d receiving period
Authors: Delver Justin , Rusche Warren C , Smith Zachary K 
Published: May 2024

Abstract
The receiving period of a feedlot calf is one of the most stressful stages in the life of that animal and can result in respiratory disease caused, in part, by reduced feed intake and transit stress. Feeding a phytomolecule compound in combination with current therapeutic strategies may aid in controlling systemic inflammation and improve the performance of newly received calves. This study determined whether a phytogenic feed additive with essential oils and plant extracts (PFA) influences measures of growth and growth efficiency during the feedlot receiving phase. The two treatments were a control group fed no additive (CON) and a treatment group fed PFA additive at a rate of 0.25 g/45.4 kg of body weight (BW; PFA). Steers were transported 285 km from an auction facility to the Ruminant Nutrition Center in Brookings, SD where they were vaccinated against viral respiratory diseases and clostridial species, and administered pour-on anthelmintic. Steers were divided into 10 replicate pens of 8 steers (305 ± 30 kg) per treatment (n = 160 steers) in a randomized complete block design. The steers were fed a basal diet [dry matter (DM) basis] containing corn silage (74%), DDGS (21%), a liquid supplement (5%), and monensin sodium (Rumensin-90, Elanco Animal Health) at 25 g/907 kg (DM basis) for 53 d. Steers were fed 2X daily with intakes closely managed for the first 14 d during adaptation to the receiving diet then a slick bunk management strategy was applied for the remainder of the study. No mortality was observed in this study, and one steer was treated for respiratory disease from the CON group. There were no significant differences observed in BW, average daily gain (ADG), variation in ADG, dry matter intake, or feed conversion efficiency from d 1 to 29, 29 to 53, or during the cumulative receiving period (P ≥ 0.11) between the CON and PFA groups. NEm and NEg did not differ between the treatments (P ≥ 0.79). The ratio of observed-to-expected dietary net energy was also not affected by dietary treatment (P ≥ 0.71). The steers used in this study were in good health and had minimal morbidity (0.63%) with no mortality during the 53-d receiving study which contributed to the feed additive having no appreciable influence on the growth and health outcomes in this study.
234 Evaluation of a phytogenic blend on post-weaning growth performance, health, and sera metabolite responses during the initial 56 d feedlot receiving period in newly weaned steers
Authors: Ribeiro Thiago Lauro Maia , Smith Zachary K , Wall Emma H , Francis Forest L , Francis Becca Grimes , Ross Cassidy , Rusche Warren C , Heldt Jeff 
Published: May 2024

Abstract
The objective of this study was to determine if a blend of capsicum oleoresin, clove essential oil, and garlic essential oil (CCG; Fytera Advance - Selko USA, Indianapolis IN) influences measures of cattle performance during the initial 56-d feedlot receiving phase. Newly weaned Charolais × Angus steers [n = 256; initial shrunk body weight (BW) = 273 ± 26 kg) were used in 56-d receiving phase experiment. Steers were transported 513 km to the Ruminant Nutrition Center in Brookings, SD on the day of weaning. Steers were individually weighed and allotted to 1 of 32 pens (n = 8 steers; 8 pens/treatment) in a randomized complete block design and randomly assigned to 1 of 4 treatments: control diet with no test product (CON); CCG at 125 mg/steer daily (CCG1); CCG at 250 mg/steer daily (CCG2); or CCG at 500 mg/steer daily (CCG3). Steers were fed twice daily, and bunks were managed using a slick bunk system from d 14 to 56; feed deliveries during the first 14 d were managed by feedlot personnel to adapt cattle to a targeted dry matter intake (DMI). The basal diet provided: 13.8% CP, 1.74 Mcal/kg NEm, and 1.07 Mcal/kg NEg. Monensin sodium was fed to all steers at a rate of 25 g/907 kg (DM basis). Steers were individually weighed on d -1, 1, 14, 35, and 56. Daily dry matter intake (DMI) was influenced by dietary treatment (quadratic effect; P = 0.01) in which steers that were fed with CON or CCG3 had greater DMI than those subjected to CCG1 and CCG2 dietary regimens. However, CCG supplementation did not result in improvements in average daily gain nor gain to feed ratio (P ≥ 0.15). A tendency for a treatment × day interaction was noted for sera non-esterified fatty acids (NEFA; P = 0.06), on d 14, steers from CCG3 had greater NEFA compared with CON and steers from CCG1 and CCG2 were intermediate (P ≤ 0.05). Dietary treatment influenced (P = 0.04) circulating concentrations of ceruloplasmin (CPL), where steers from CCG2 and CCG3 resulted in decreased circulating concentrations of CPL compared with CON and CCG1, indicating less inflammation. In conclusion, steers supplemented CCG3 had greater DMI and decreased ceruloplasmin suggesting an overall improvement in health status. Steers from CCG3 had increased NEFA on d 14, which could imply a catabolic state; However, sera NEFA decreased over time compared with the other treatments. More research is necessary to determine the consistency of the performance responses and better understand the correct dosage of CCG fed to newly weaned beef calves.
233 Inclusion of a multispecies fungal feed additive in forage-based diets fed to beef cattle: Effects on growth performance and ruminal fermentation
Authors: Pittaluga Alejandro , Relling Alejandro E 
Published: May 2024

Abstract
The objective was to evaluate the effect of adding a multispecies fungal feed additive (MFA; Aspergillus flavus, Aspergillus niger, Aspergillus oryzae) to forage-based diets fed to beef cattle on growth performance and ruminal fermentation. Experiment 1 evaluated the effect of supplementing Angus × SimAngus-crossbred steers [n = 80; initial body weight (BW) = 370 ± 44 kg] with varying doses of an MFA in a randomized complete block design. Steers were blocked by BW and housed in 8 feedlot pens (randomly assigned 2 pens per treatment) where a hay-based diet was fed for 122 d. The hay-based diet was offered with the inclusion of the MFA at 0.02, 0.04, and 0.08 % of the diet dry matter (DM), or without the inclusion of the MFA (CON). Steers were weighed at 28-d intervals. For experiment 2, ruminally cannulated Angus × SimAngus cows (n = 4; initial BW = 569 ± 21 kg) were used in a crossover design with two 21-d study periods to evaluate the effect of dietary inclusion of an MFA on in situ digestion and rumen metabolites. Treatments consisted of a forage-based diet with (WFA) or without (CON) the inclusion of the MFA. In situ digestion was evaluated on d 5, 10, and 20 throughout each period. In-situ bags were incubated in the rumen for 0 to 36 h, sampling every 4 h. On d 20, samples of ruminal fluid were collected to analyze short-chain fatty acids (SCFA) concentration. All data were analyzed using the PROC MIXED procedure of SAS. For experiment 1, a polynomial contrast was used. For experiment 2, the interaction between period and treatment was not significant (P &gt; 0.45). In Experiment 1, the final BW, average daily gain (ADG), and gain to feed ratio (G:F) changed cubically (P ≤ 0.04; Table 1) as dietary inclusion of the MFA increased. Steers supplemented with the MFA at a rate of 0.02% of the diet DM were heavier at the end of the 122-d study period and had the greatest ADG and G:F among treatments. No differences between treatments (P ≥ 0.37) were observed for dry matter intake. In Experiment 2, no treatment × time interactions and treatment effects were detected (P ≥ 0.17; Table 2) for the in-situ disappearance rate and degradation kinetics of the diet DM, neutral detergent fiber, and acid detergent fiber. In addition, MFA supplementation did not affect (P ≥ 0.13; Table 3) the SCFA profile and the total SCFA content in the rumen fluid. Results from these studies indicate that dietary inclusion of an MFA might be an effective alternative to increase the feed efficiency of beef cattle-fed forage-based diets. However, the precise mode of action warrants further investigations.
296 Effects of dietary antimicrobials on the ruminant gastrointestinal tract microbiome
Authors: Vincent Tyler J , Nolasco Lester R , Suriyapha Chaichana , Johnson Timothy A , Schoonmaker Jon P 
Published: May 2024

Abstract
Monensin, tylosin, and chlortetracycline (CTC) are antimicrobials frequently employed in high grain feedlot cattle diets to inhibit liver abscesses and enhance growth. However, increased public concerns regarding antibiotic resistance have created a pressing need to develop alternative strategies. A more mechanistic understanding of how antimicrobial drugs effect the microbiome in the ruminant gastrointestinal tract (GIT) may help develop effective alternatives. Therefore, the objective of this study was to determine changes in the GIT microbiome of grain-fed feedlot steers after antimicrobial drug administration. Thirty individually housed Angus x Simmental steers [body weight (BW) = 355 ± 16.8 kg] previously fed a 56% forage diet were immediately transitioned to a 93% concentrate diet and assigned to one of three treatments (10 steers/treatment): 1) control, without antibiotics, 2) 75 mg of tylosin and 200 mg of monensin per animal per day (TYLMON), and 3) 70 mg of CTC per animal per day. Fecal samples were collected on d 0, 7, 14, 28, 56, 112, and at slaughter and digesta were obtained from the rumen, jejunum, and cecum at slaughter. DNA was extracted from samples, amplified via 16S PCR, and sequenced. Jejunal samples had the least alpha diversity compared with ruminal, cecal, or fecal samples (P &lt; 0.001). There were no differences in measures of alpha diversity in the ruminal, jejunal, or cecal digesta at slaughter (P ≥ 0.10). However, overall measures of alpha diversity (Shannon entropy, observed features) in feces were greater in CTC-fed steers (P ≤ 0.009) as well as in TYLMON-fed steers (P ≤ 0.04) compared with control steers. Measures of alpha diversity for all treatments decreased in feces from d 0 to 7, then increased from d 7 to slaughter (time effect, (P ≤ 0.001). There were no differences in fecal alpha diversity between treatment groups on d 0 (P ≥ 0.50), but by d 28 both TYLMON and CTC treated steers had greater fecal alpha diversity compared with the control steers (P ≤ 0.05). With regard to differential abundance, Phascolarctobacterium and Prevotellaceae UCG-003 were more abundant in feces of control steers relative to antimicrobial treated steers (P &lt; 0.05). Bifidobacterium, Dorea, CAG-56, and Erysipelotrichaceae UCG-003, were the 4 genera found to be in the greatest abundance in the feces of TYLMON-fed relative to control steers (P &lt; 0.05). Akkermansia, Succinivibrio, and Turicbacter were the 3 genera found to be in the greatest abundance in the feces of CTC-fed compared with control steers (P &lt; 0.05). Taken together, these data suggest that differences in the microbiome associated with dietary antimicrobial treatment occur to a greater extent in the lower sections of the GIT, and that these changes in the microbiome occur after 28 d of feeding.
294 Development of a model to predict forage intake and growth of bottle-fed Holstein calves
Authors: Lancaster Phillip A , Baldin Geovana C , Hildebrand Caleb , Larson Robert 
Published: May 2024

Abstract
Models to predict intake and growth of preweaning calves have received less attention than postweaning calves. The objective was to develop a model to predict forage intake and growth of bottle-fed Holstein calves. Data on milk intake, alfalfa hay intake, and body weight (BW) of 40 Holstein calves from birth to 200 d of age were acquired from Abdelsamei (1989). Milk and forage intake equations were those used by Lancaster et. al. (2021; 10.1093/jas/skaa406). NASEM growth equation evaluation and new equation development were performed using a dataset compiled from the literature by Hildebrand et al. (2022; 10.1093/jas/skac064.321). The mean absolute error to predict milk intake was less for WOOD at peak milk less than 10.88 kg/d, and was less for NASEM at peak milk greater than 10.88 kg/d. A combination of NASEM and WOOD milk yield equations to predict milk intake resulted in CCC of 0.969 and MB of -0.74% and was used to predict milk intake in subsequent analyses. Prediction of forage intake by TED06, BAK76, TED09A, TED09B, and HOL82 had CCC of 0.878, 0.920, 0.729, 0.874, and 0.234 with MB of -17.49, -1.58, -64.40, -35.60, and -341.16%, respectively. Prediction of BW for the same intake equations with the NASEM growth equation had CCC of 0.876, 0.929, 0.819, 0.864, and 0.402 with MB of -21.54, -14.67, -30.10, -25.13, and -99.78%, respectively. With observed BW, prediction of forage intake by TED06, BAK76, TED09A, TED09B, and HOL82 resulted in CCC of 0.935, 0.936, 0.958, 0.964, and 0.640 with MB of -0.55, 6.57, -11.90, -8.83, and -92.26%, respectively, indicating high precision and moderate accuracy. With observed forage intake, prediction of BW by the NASEM growth equation resulted in CCC of 0.926 and MB of -17.08% indicating high precision and poor accuracy. Evaluation of the NASEM growth equation in Holstein cattle resulted in CCC of 0.329 and MB of 61.47%. A new growth equation was developed: EBG, kg/d = 0.78498 ± 0.24035*RE, Mcal/d^(0.78500 ± 0.06033)*EBW, kg^(-0.14323 ± 0.0742) with RMSE = 0.0599 ± 0.0207 and R2 = 0.8795 ± 0.1078. With observed forage intake, prediction of BW with the new growth equation resulted in CCC of 0.992 and MB of -0.11%. With the new growth equation, prediction of forage intake by TED06, BAK76, TED09A, TED09B, and HOL82 resulted in CCC of 0.914, 0.766, 0.881, 0.901, and 0.412 with MB of 15.47, 40.53, 18.11, 17.02, and -172.88%, respectively. Prediction of BW resulted in CCC of 0.978, 0.940, 0.968, 0.969, and 0.701 with MB of 2.83, 8.91, 3.87, 3.92, and -38.73%. In conclusion, prediction of forage intake and BW in Holstein calves were hindered by use of the NASEM growth equation, and a new growth equation more precisely and accurately predicted forage intake and body weight.
295 Development of a model to predict forage intake and growth of nursing beef calves
Authors: Lancaster Phillip A , Baldin Geovana C , Hildebrand Caleb , Larson Robert 
Published: May 2024

Abstract
Models to predict intake and growth of preweaning calves have received less attention than postweaning calves. The objective was to develop a model to predict forage intake and growth of nursing beef calves. Data on milk intake, forage intake, and body weight (BW) of 51 Hereford calves from birth to 200 d of age were acquired from Boggs (1977). Milk and forage intake equations were those evaluated by Lancaster et. al. (2021; 10.1093/jas/skaa406). Forage digestibility was evaluated with a dataset on in vitro and in vivo measurements. Milk energy concentration was evaluated with a dataset on milk yield and composition. NASEM growth equation was evaluated using the dataset of Hildebrand et al. (2022; 10.1093/jas/skac064.321). Model precision and accuracy were evaluated using the concordance correlation coefficient (CCC) and mean bias (MB). The NASEM and WOOD milk yield equations predicted milk intake reasonably well (CCC = 0.796 and 0.820; MB = 4.29% and 1.31%, respectively); the WOOD equation was used in subsequent analyses. Forage intake prediction was imprecise (CCC = 0.348 to 0.613) and inaccurate (MB = 19.36 to 57.67%). Body weight prediction was moderately precise (CCC = 0.574 to 0.766) and moderately accurate (MB = 6.39 to 15.79%). With observed BW, forage intake prediction was moderately precise (CCC = 0.528 to 0.834) and highly to poorly accurate (MB = 0.81 to 27.56%). With observed forage intake, BW prediction by the NASEM growth equation resulted in CCC of 0.821 and MB of 9.69%. Published equations relating IVDMD to in vivo OMD were imprecise (CCC = 0.437 to 0.520) and moderately to highly accurate (MB = -9.46 to 7.67%). A new equation was developed: OMD, % = 7.7719 ± 4.3825 + 0.8937 ± 0.0772*IVDMD, % with RMSE = 2.803% and R2 = 0.9055. Milk energy concentration changed with days in milk (DIM; P &lt; 0.05) and milk yield (P &lt; 0.05): Energy, Mcal/kg = 0.7525 ± 0.0037 + 0.00069 ± 0.00016*DIM -0.00012 ± 0.00003*DIM*Yield, kg/d with RMSE = 0.031 and R2 = 0.527. Evaluating the NASEM growth equation in beef cattle resulted in CCC of 0.777 and MB of -13.56%. A new equation was developed: EBG, kg/d = 7.9279 ± 0.8254*(RE, Mcal/d/EBW, kg0.75) ^0.7083 ± 0.0385 with RMSE = 0.1127 and R2 = 0.6940. With observed forage intake, BW prediction with new equations resulted in CCC of 0.901 with MB of 1.58%. With the new equations, forage intake prediction by TED06, BAK76, TED09A, TED09B, and HOL82 resulted in CCC of 0.822, 0.700, 0.434, 0.686, and 0.380 with MB of -7.01, -5.08, 36.87, 13.24, and 10.96%, respectively. Body weight prediction resulted in CCC of 0.935, 0.938, 0.896, 0.926, and 0.886 with MB of -7.34, -6.21, -0.09, -5.35, and -9.41%. In conclusion, prediction of forage intake and BW in nursing beef calves were hindered by use of IVDMD, constant milk energy concentration, and the NASEM growth equation.
306 Awardee Talk: Characterization and surveillance testing of problematic pathogens within the livestock industry using metagenomic and long read sequencing
Authors: Neujahr Alison C 
Published: May 2024

Abstract
With increased intensification of livestock production, the rate of disease susceptibility and emergence of pathogens has increased. Currently in the beef cattle industry, infectious bovine keratoconjunctivitis (IBK), is a problematic disease that is not well understood where vaccines have shown to have low efficacy. This is partly due to the lack of understanding of the ocular microbiome, where IBK disease progression may be a result of a polymicrobial disease due to certain bacterial and/or viral taxa predisposing the animal to infection. To understand the microbial ecology of IBK we used metagenomic shotgun sequencing to characterize the bovine ocular microbiome and virome. Infected and healthy beef calves were sampled before, during, and after IBK infection and shotgun metagenomic sequencing was performed to identify microbial changes during IBK infection. Preliminary data showed that we were able to identify 230 contigs consisting of bacteriophages such as Escherichia virus, Bacillus virus, Corynebacterium virus, and Mycoplasma virus. Out of the 230 bacteriophages, 213 of them are lytic phages. Additionally, preliminary data showed bacteria contigs such as Moraxella bovoculi, and Mycoplasma bovoculi Like IBK, the rate of disease emergence has increased in the last decade. As such, rapid in-field surveillance tools are greatly needed to monitor the emergence of known and unknown pathogens for early intervention. Current tools such as RT-PCR and enzyme linked immunosorbent assay (ELISA) require previous genomic knowledge to detect pathogens and are limited to the pathogen of interest. We have developed a long-read sequencing-based surveillance tool that eliminates the need of prior knowledge to detect both bacterial and viral pathogens simultaneously. The approach we developed can rapidly and accurately identify pathogens within clinical samples in as short as 12 h from sample collection to results. Here we present sequence-based microbiome studies and tools to help understand disease etiology and develop novel surveillance tools to improve food security within the livestock industry.
9 Use of new technology to measure methane emissions
Authors: Thompson Logan , Beck Matthew 
Published: May 2024

Abstract
Over recent decades, the impact of human-induced climate change and the role of ruminant agriculture has been of growing concern for both the public and the scientific community. This has led to rapid advancements in technology needed to measure methane emissions accurately and precisely. Primarily, these advancements have been focused on measurements of enteric methane, with the proliferation of GreenFeed emission measurement systems (GEM; C-Lock, Inc; Rapid City, SD) being utilized by animal scientists across the world. The GEM relies on spot measurements collected in a portable head-box, either in a freestall or on a trailer. The GEM uses bait feed to entice animals to place their head into the head-box to collect measurements. Use of respiration chambers or head-boxes are still considered the “gold standard”, but the GEM allows for quantification in production environments and with greater number of animals. While enteric emissions are the primary source of methane from ruminant agriculture, manure methane emissions account for 15.8% of direct emissions from cattle in the U.S. This emission source is a significant contributor to confined feeding operations’ greenhouse gas emissions (GHG), where consolidation and changes in manure handling practices have occurred over the last several decades. From 2010 to 2020, manure methane emissions were a larger contributor to climate warming than enteric methane (90.8 MMT CO2-we vs. 89.2 MMT CO2-we, respectively) when calculated using the new GWP* metric. However, few advancements have been made in quantifying emissions from manure, with the cost-effective static chamber methodology still widely used. This technique allows for the determination of temporal gas concentration change in a known volume of air with a PVC cylinder, inserted 5-10 cm in the soil and posteriorly closed with a PVC lid to generate “known volume” headspace. However, this method does have known limitations on spatial and temporal flux calculations. These limitations include: the PVC chamber may alter the soil microenvironment thereby altering soil GHG flux estimates; they have potential for technician bias; and are short term monitoring, limiting interpretations to that snapshot in time and making comparisons across experiments difficult. Differing measuring techniques, such as eddy covariance and dual-comb, that more accurately and precisely monitor the soil-atmosphere interface may help better understand gas fluxes from livestock systems.
Key Word: cattle, enteric, manure, methane