bluuebunny/crossref_metadata_2025_split huggingface dataset:
70 Nutrient Restriction During Late Gestation Alters Maternal Circulating Amino Acid Concentrations in Primiparous Beef Females
Authors: Redifer Colby A , Wichman Lindsey G , Meyer Allison M 
Published: October 2023

Abstract
We hypothesized that maternal circulating AA concentrations would be reduced by late gestational nutrient restriction, indicating less available nutrients for transport by the uteroplacenta to the growing fetus. Fall-calving Hereford-SimAngus heifers [single-sired; BW: 451 ± 28 (SD) kg; BCS: 5.4 ± 0.7] bred to a single sire were allocated by fetal sex and expected calving date to receive either 100% (control; CON; n = 12) or 70% (NR; n = 13) of NASEM metabolizable energy and metabolizable protein requirements for maintenance, pregnancy, and growth from day 160 of gestation to calving. Heifers were individually fed chopped sorghum sudan hay (1.74 Mcal ME, 6.66% CP, 72.0% NDF; DM basis) and based on individual intakes, supplemented to meet targeted nutritional planes. Jugular blood samples were obtained on days 159 (Pre-treatment), 202, and 244 of gestation, and 1 h post-calving to determine serum concentrations of the 20 common AA (except cysteine), 1-methyl histidine, and 3-methyl histidine. Gestational and post-calving AA were analyzed separately with nutritional plane, treatment initiation date, and calf sex (when P &lt; 0.25) as fixed effects. Gestational AA included day and nutritional plane x day using repeated measures. We have previously reported that dam BCS was less (P ≤ 0.04) by day 202 of gestation and dam BW was less (P ≤ 0.01) by day 223 of gestation for NR dams. Post-calving, NR dams were 64 kg BW and 2.0 BCS lless (P &lt; 0.001), but calf birth weight was not affected (P = 0.72) by nutritional plane. Histidine, lysine, and methionine were greater (P ≤ 0.03) in NR dams on day 202 of gestation. Tryptophan and valine were less (P ≤ 0.05) while methionine and total AA tended to be less (P ≤ 0.08) on day 244 of gestation in NR dams. Aspartic acid, glutamic acid, and tyrosine were less (P ≤ 0.03), but 3-methyl histidine was greater (P ≤ 0.01) on days 202 and 244 of gestation in NR dams. 1-methyl histidine was greater (P ≤ 0.05) at all 3 gestational timepoints but leucine was less (P = 0.03) in NR dams during gestation. Post-calving, glutamic acid, leucine, and valine were less (P ≤ 0.04), and methionine, threonine, tryptophan, tyrosine, and total AA tended to be less (P ≤ 0.10) in NR dams. Histidine, 1-methyl histidine, 3-methyl histidine, and serine were greater (P ≤ 0.03) in NR dams post-calving. In summary, late gestational nutrient restriction reduced total maternal circulating AA and altered the maternal serum AA profile, but calf birth weight was not affected. Individual AA that were greater or unaffected in NR dams were likely indicative of body protein catabolism occurring to meet nutrient requirements.
161 The Effects of Feeding Hempseed Cake on Pancreatic and Intestinal Enzymatic Activity in Finishing Heifers
Authors: Mia Md Golam Kafi Afrose , Winders Thomas , Yusuf Mustapha , Serum Eric , Smith David J , Neville Bryan W W , Amat Samat , Dahlen Carl R , Swanson Kendall C 
Published: October 2023

Abstract
Due to the unique nature of the rumen, unlike monogastric animals, ruminants like cattle largely depend on microbial hydrolysis of feed rather than post-ruminal enzymatic degradation. However, in ruminants fed high-grain diets, significant amounts of starch can bypass ruminal fermentation, where pancreatic and small intestinal enzymes play a vital role in digestion. Ruminal microbiota, as well as the host animal, require protein as a nitrogen source to optimize digestibility. Hempseed cake (containing &gt;30% of crude protein) is a by-product of hempseed oil production, but currently is not used as a feed source as it is not an FDA-approved feed ingredient. Presently, the availability and costs of protein supplements are volatile, and sourcing alternative protein sources is needed. Therefore, information is necessary on the effect of feeding hempseed cake on ruminant digestive function. This study aimed to evaluate the effects of feeding hempseed cake on pancreatic and intestinal enzymatic activity in finishing heifers. Angus-crossbred finishing heifers (494 ± 10 kg BW) were fed for 111 days with one of two dietary treatments: 20% [dry matter (DM) basis] of dried corn distillers grains plus solubles (n = 16, control) or hempseed cake (n = 16, hemp). All animals were slaughtered at the end of treatment. Intestinal tissues for digestive enzyme assays were isolated and stored at -800C following immediate flash freezing with liquid nitrogen. The MIXED procedure in SAS was used to analyze the data. There was a tendency (P = 0.09) of greater pancreatic tissue mass in the hemp group than in the control group. The activity of pancreatic α-amylase, trypsin, and lipase relative to protein (U/g protein) was less (P &lt; 0.01) in heifers fed hemp than in heifers fed distillers grains primarily because protein concentration (mg/g) and content (g/pancreas) were greater (P &lt; 0.01) in the hemp group than the control group. However, there were no differences (P ≥ 0.2) in digestive enzyme activity (U/g of tissue) in pancreatic and small intestinal tissues. Overall, our results suggest that there was no adverse effect of feeding hemp on the enzymes responsible for nutrient digestion in the small intestine and that hempseed cake may be useful as an alternative source of protein in cattle fed finishing diets.
167 Timing of Implants use in a Backgrounding System
Authors: Butterfield Kylie , Adair Kelton , Nuttelman Brandon L , Erickson Galen E , Drewnoski Mary E , MacDonald Jim C 
Published: October 2023

Abstract
A 2-year study conducted at the Eastern Nebraska Research and Extension Center near Mead, Nebraska determined the effects of backgrounding rate of gain and implanting during the winter or summer phases on animal performance and carcass traits. The study design was a 2 x 3 factorial arrangement with the factors of winter gain (0.45 or 0.90 kg/d; LG and HG, respectively) and three implant strategies. The implant strategies included a 36 mg zeranol (Ralgro; Merck Animal Health, De Soto, KS) implant during the winter phase and 40 mg trenbolone acetate and 8 mg estradiol (Revalor-G; Merck Animal Health) implant during the summer phase (STRNG), no implant during the winter phase and Rev-G during the summer phase (MED), and no implant during the winter or summer phases (NONE). The study used 240 (initial BW = 247 kg, SD = 5.9 kg YR 1; BW = 255 kg, SD = 10.9 kg YR 2) weaned steers each year that were fed one of two backgrounding diets consisting of bromegrass hay and 10% MDGS (LG) or 30% MDGS (HG). Steers were backgrounded in the feedlot for a 148-day winter phase followed by a 56-day summer phase where they grazed smooth bromegrass paddocks. Upon arrival in the feedlot for the finishing phase, steers received 200 mg TBA and 40 mg estradiol (Revalor-XS; Merck Animal Health) and were fed a common diet for the entire finishing phase. In the winter phase, steers fed the HG diet had a greater ADG, ending BW, DMI, and improved G:F over steers fed LG (P &lt; 0.01). Steers that received a Ralgro implant during the winter phase (STRNG) were observed to have an 13% improved ADG (P &lt; 0.01), a 10% increase in G:F (P &lt; 0.01), and an additional 14 kg of BW for the winter phase. There were no interactions between the rate of gain and implant strategy (P ≥ 0.15) during the winter period. In the summer, HG steers had maintained greater ending BW than LG, although LG steers had greater ADG than HG (0.70 and 0.53 kg, respectively; P &lt; 0.01) due to compensatory gain. Steers assigned to HG during the winter phase had a greater IBW for the finishing phase. Steers fed HG during the winter and administered an implant at both backgrounding phases (STRNG) had the greatest HCW with no differences in ADG or G:F during the finishing phase. Combining a strong implant program and an increased rate of gain during winter backgrounding resulted in 34 kg of additional HCW at marketing. Implant strategy and rate of gain during the winter growing period had additive effects to increase animal performance through all phases.
162 Kernel Processing Corn Silage Included at 65% of the Diet (DM Basis) and fed to Growing Beef Steers Increases dry Matter Intake, Decreases Apparent Total Tract Digestibility of Neutral Detergent Fiber, and Does not Enhance Starch Digestibility
Authors: Grimes Becca , Francis Forest L , Gubbels Erin R , Rusche Warren C , Smith Zachary K 
Published: October 2023

Abstract
The objective of this study was to evaluate the effects of kernel processing of corn silage on apparent total tract digestibility (ATTD) of steers fed corn silage included at 65% of the diet (DM basis). Steers (n = 184; initial shrunk BW = 338 ± 22.3 kg) were assigned to 1 of 24 pens (8 steers/pen). Pens were randomly assigned to one of two dietary treatments (12 pens/treatment): non-kernel processed corn silage included at 65% diet DM (CON) or kernel processed corn silage included at 65% diet DM (KPCS) in a randomized complete block design with pen as experimental unit. Steers from replicates 1 to 8 spent 47-d on test and steers from replicates 9 to 12 were fed for 46-d on test. On the final day of the study, apparent total tract digestibility of diet dry matter (DM), organic matter (OM), neutral detergent fiber (NDF), N, and starch was determined using an internal marker ratio technique using the undigested NDF residue following a 240 h in-situ incubation in ruminal fluid (uNDF240). Diet samples were collected twice daily (morning and afternoon) starting two days prior to fecal collections. Fecal collections were taken via rectal palpation on the final day of the study. Data were analyzed as a RCBD with fixed effects of KPCS diet and random effect of block (location within feedyard). Kernel processing increased DMI by 6% (P = 0.01) during the collection period and cumulative DMI throughout the study was increased by 2% for KPCS treatment (P = 0.04). Kernel processing did not enhance the ATTD of DM, OM, or starch (P ≥ 0.71), but did decrease ATTD of NDF by approximately 6% (P = 0.04) compared with corn silage that was not kernel processed. Furthermore, kernel processing was determined to increase ATTD of N by 5% (P = 0.05). These results indicate that kernel processed corn silage may decrease apparent total tract digestibility of neutral detergent fiber due to greater intake but does not appreciably influence starch digestibility.
165 Interactions Between Steroidal Implants and Zinc Supplementation in Feedlot Steers
Authors: Smerchek Dathan T , Rients Emma L , McLaughlin Amy M , Thornton-Kurth Kara J , Hansen Stephanie L 
Published: October 2023

Abstract
Angus-cross steers (n = 144; 362 kg ± 20.4) were used to determine the interaction of Zn and steroidal implants on growth and trace mineral (TM) status. Steers (n = 6/pen) were stratified by BW in a 3 × 2 factorial arrangement. Dietary treatments were fed for 60 days pre-implant, with a roughage-based diet from d -60 to -38, transition to a high concentrate diet, and 23 d on finishing diet before implant. Dietary treatments (8 pens per treatment; Zn as ZnSO4) included: 1) no supplemental Zn (analyzed 54 mg Zn/kg DM; Zn0); 2) 30 mg supplemental Zn/kg DM (Zn30); 3) 100 mg supplemental Zn/kg DM (Zn100). Within Zn treatment, steers received a steroidal implant treatment on d 0: 1) no implant; NO; or 2) high potency combination implant (TE-200, Elanco, Greenfield, IN; 200 mg TBA, 20 mg E2; TE200). Body weights were taken on d -1, 0, 28, 56, and 89, 90. Liver and blood were collected on d 0, 20, 40, and 84 for TM. GrowSafe bunks recorded individual feed intake (steer as experimental unit; n = 24 per treatment). Proc Mixed of SAS evaluated linear and quadratic effects of Zn within implant treatments and the effect of supplemental Zn within TE200. Performance and carcass characteristics used d -60 BW as a covariate. Plasma and liver TM data were analyzed as repeated measures. After 60 d plasma Zn was similar amongst Zn treatments (1.36 mg/L; P = 0.15). TE200 tended to decrease plasma Zn 8.4% from d 0 to 20 whereas NO cattle decreased 3.6% (implant × day; P = 0.08). Supplementation of Zn increased overall liver Zn concentration (P = 0.05). TE200 decreased liver Mn 13.8% from d 0 to 20 while NO decreased 1.2% (implant × day; P = 0.01). During the first 28 d post-implant, no linear or quadratic effects of Zn were noted within NO or TE200 for BW, ADG, G:F, or DMI (P ≥ 0.12). However, within TE200, Zn supplementation improved d 0-28 ADG and G:F (P ≤ 0.04). From d 56-90 steer performance was lackluster; however, within TE200, increasing concentration of supplemental Zn tended to linearly increase G:F (P = 0.07). Within TE200, marbling tended to be quadratically affected (P = 0.06) where Zn30 was lesser than Zn100 with Zn0 intermediate. No additional linear, quadratic, or Zn within TE200 carcass responses (P ≥ 0.11) were noted. From d 0 to 28 Zn supplementation improved ADG and G:F of implanted steers; beyond this, few growth performance differences were noted due to Zn. However, liver and plasma TM results are consistent with our prior work, suggesting steroidal implants increase demand for Zn and Mn following implant administration to support improved growth and efficiency.
267 Efficacy of Using the Elastic net Regularized Regression Method to Predict Body Weight of Beef Heifers Using Body Measurements and Calculated Frame Score
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
Several methods to estimate the body weight (BW) of cattle have been proposed. Body measurements have proved to be useful in estimating the BW of cattle. However, there are multicollinearities between body measurements which could affect the accuracy of prediction models. Least absolute shrinkage and selection operator (LASSO regression), ridge regression, and more recently elastic net (EN) regularization has been suggested to handle multicollinearity better than simple regression. Elastic net is a regularization technique that combines LASSO and ridge regression. In this study, we modelled BW against some body measurements [calculated: volume (VL) 218 to 503 liters; frame score (FS) 2.1 to 7.5; surface area (SA) 4.02 to 7.1 m2], and direct body measurements [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; flank girth (FG) 156 to 239 cm] to examine which variable(s) predicts BW more accurately. Data from 300 heifers (9 breeds) collected over 4 years were used with year as a random effect to account for differences between years. We ran the EN model using the glmnet function of the R caret package. Ten-fold cross validation was used with 5 repeats. The EN model was trained using 206 observations and validated with 94 observations. The best model was selected based on the minimum root mean square error and median R-square (R2) values. Including FS in the prediction model resulted in the highest R2 (0.5754) and was a better predictor for BW compared with other models: VL (0.4271), SA (0.4130) and direct body measurements (0.4861). This suggests that calculated FS could be a better estimate for BW than direct body measurements and indicates that FS still accurately predicts size of heifers.
92 Methane Mitigation in Dairy Animals Begins Before Birth with Opportunities to Impact Throughout Life
Authors: French Elizabeth A 
Published: October 2023

Abstract
Research efforts are underway to identify methane mitigators in the dairy sector to reach net zero carbon emissions, and ideally, net negative global emissions. Methane mitigation is multifactorial, including strategies in genetics, management, diet composition, diet nutrient composition, and implementation of feed additives. Research efforts thus far have primarily focused on adult ruminants. Research on how calf management and its impact on phenotypic traits including milk production and methane production is currently lacking. Supplying different levels of nutrients in late lactation results in demonstrated splits in feed intake, average daily gain, metabolism, and greenhouse gas emissions from their offspring. Post-calving, nutrient-restricted heifers entering the lactating herd are hypothesized to be less productive and have greater environmental impact due to reduced productive efficiency relative to their control herd mates. Identification of feed additives that are locally sourced, alter the rumen microbiome, and have lifetime reductions on emissions are under investigation. Further research efforts include identifying metabolic and genetic profiles to identify animals in early life as either high or low methane emitters. Being able to classify animals early in life can reduce the total economic inputs used to raise animals and reduce the total environmental impact of these animals through early culling or intervention of high methane emitting animals. The goal of this presentation is to discuss current knowledge and future potential of calf management, feeding regimes, and feed additive implementation to reduce methane emissions and total environmental impact in the dairy industry.
91 Methanogen Ecology in the Ruminant Hindgut
Authors: Ricke Steven C 
Published: October 2023

Abstract
Environmental methane production continues to be an ongoing global concern and interest is growing to reduce total methane production. As a part of this collective effort mitigation of methane production in ruminants has become one of the targets for ongoing research. Several strategies have emerged including dietary manipulation, administration of unique feed additives that specifically target methanogens, and host animal modulation approaches. Most of these efforts have focused on the rumen methanogen population and understanding their ecology in relationship to the non-methanogen microbial population. However, there is potential for methane production in the hindgut of the ruminant animal, and this should be considered in any overall strategy for mitigation of methane production in ruminants. The emphasis of this presentation is to discuss the current knowledge and future prospects for understanding the contribution of hindgut methanogens to overall ruminant methane production and their potential for contribution to mitigation of ruminant methane production.
306 Nutrient Digestibility and Dietary Energy Values in Growing Pigs Fed a Corn Distillers Dried Grains with Soluble (Cddgs)-Based Diet with Multi-Enzyme Supplementation
Authors: Halbur Joseph G , Hong Jinsu , Llamas-Moya Sara , Duong Tri , Kitt Steve J , Weaver Eric , Bertram Mark 
Published: October 2023

Abstract
Dietary enzyme supplementation may enhance the digestibility and utilization of non-starch components of the diet by pigs. This study was conducted to evaluate the efficacy of a multi-carbohydrase enzyme (ENZ) in growing pigs for apparent ileal digestibility (AID) of amino acids (AA), apparent total tract digestibility (ATTD) of nutrients and energy values in a corn distillers dried grains with solubles (cDDGS)-based diet. A total of 12 ileal-cannulated pigs [initial body weight (BW) = 31.7 kg ± 3.04] were housed in individual metabolic crates for 21 days (Period 1) and subsequently transferred to individual floor pens for additional 28 days (Period 2). These animals were assigned to 2 diets (n = 6) in a completely randomized design (CRD). The diets were formulated on corn, soybean meal and cDDGS (30%) without (CON) or with ENZ supplementation. The ENZ (Proprietary xylanase/cellulase product, Kerry Inc.) was included in the diets at 200 g/tonne. Feeds were formulated to 1.15% SID lysine and met or exceeded nutrient requirements for growing pigs (NRC, 2012). Pigs were fed diets at three times maintenance energy requirement based on BW, which was assessed at every 2 weeks intervals throughout the study, Titanium dioxide was added to the diets as an indigestible marker. In period 1, pigs had 14 d of adaptation, followed by 4 d fecal and urine using the total collection method and 2 d ileal digesta collection. In period 2, pigs had 23 days adaptation, followed by 2 d fecal collection and 2 d illeal digesta collection. The AID of AA and gross energy (GE) and ATTD of nutrients and GE were calculated by an index method. Data were analyzed as a CRD, using pig as the experimental unit and enzyme supplementation as the main effect. Overall, average daily gain and gain:feed ratio of pigs were 857 and 918 g/d and 0.52 and 0.54 for CON and ENZ, respectively (P &gt; 0.05). In period 1, ENZ supplementation improved (P &lt; 0.05) the ATTD of dry matter (DM), ash, organic matter (OM), neutral detergent fiber (NDF), and GE by 4.4%, 26.8%, 2.8%, 11.3%, and 3.6%, respectively. Also, ENZ tended to improve (P &lt; 0.10) the ATTD of crude protein (CP) by 7.4% and AID of threonine, CP, and GE by 6.6%, 7.6%, and 13.7%, respectively. In period 2, ENZ improved (P &lt; 0.05) the ATTD of DM, ash, OM, CP, NDF, and GE by 5%, 30.1%, 3.4%, 4.1%, 19.6%, and 4.2%, respectively. similarly, EMZ improved (P &lt; 0.05) the AID of threonine, CP, and GE by 4.2%, 6.0%, and 6.4%, respectively. In conclusion, multi-carbohydrase supplementation in a corn-SBM diet with 30% cDDGS increased the digestibility of nutrients and energy in growing pigs and may represent a useful strategy to optimize the utilization of such raw material.
33 Effect of Utilizing Nurse Sows Compared with no Nurse Sows on Farrowing House Productivity
Authors: Meier Larissa E , Allen Kacey N , Cross Amanda , Mauch-Swinford Emily , Stephenson Ethan , Sonderman John , McNeil Brady 
Published: October 2023

Abstract
As number of piglets born alive increases, producers are faced with managing large litters in farrowing. Incorporating nurse sows is one strategy producers have used to assist with increased number born alive. The objective of this study was to evaluate differences in sow farm productivity in farrowing rooms with 0% nurse sows (NoNurse) and rooms with 7% nurse sows (Nurse). Crossbred sows (n = 618), ranging from parity 1 to parity 6, were assigned to farrowing rooms based on farrow date (DNA L241, DNA Genetics, Columbus, NE). At birth, all pigs (n = 9109) were individually tagged and weighed. For both treatments, cross-fostering occurred within the first 24 hours after birth within treatment. Pig movements were limited as much as possible for sows, with born alive between 13 and 15 pigs, to maximize the number of sows lactating her own pigs. If cross-fostering was necessary, pigs were placed on sows to maximize functional teat count. Farrowing rooms had 14 crates. Nurse treatment left 1 crate open (7%) to bring in a nurse sow between days 3-5 of lactation. Pigs lagging in BW gain relative to their peers (fall-behind pigs) in the Nurse treatment room were identified, weighed, and moved to a nurse sow. In NoNurse treatment, fall-behind pigs were marked and weighed but remained on their original dam. Littermates of the fall-behind pigs were also weighed for both treatments. Pigs were weaned at approximately 21.5 days of age and weaning weights were recorded. Mortality reason and date were recorded throughout the trial. Birth weights of pigs were not statistically different (P = 0.29) between NoNurse and Nurse treatment rooms. However, birth weights for fall-behind pigs were on average 0.34 kg less than non-fall-behind pigs (P &lt; 0.05) regardless of treatment. Fall-behind pigs in the NoNurse treatment were on average 0.75 kg (P &lt; 0.05) less at weaning than the fall-behind pigs in the Nurse treatment. NoNurse treatment sows weaned on average 0.73 more pigs (P &lt; 0.05) than Nurse treatments sows. There was no difference in pre-weaning mortality between the Nurse and NoNurse treatments (P = 0.48). Producers should continue evaluating strategies to assist with the increase in born alive due to the impact on weaning performance.