bluuebunny/crossref_metadata_2025_split huggingface dataset:
367 Early Fetal to Neonatal Vitamin a Supplementation Improves Growth Performance and Development of Muscle and Pre-Adipocyte in Korean Native Calves
Authors: Jin XueCheng , Peng DongQiao , Jeong WangYong , Lee JunHee , Jalil Ghassemi Nejad , Lee JaeSung , Lee HongGu 
Published: November 2023

Abstract
This study aimed to investigate the effects of vitamin A supplementation during the early fetal to neonatal stages on growth performance, blood metabolites, and the development of muscle and pre-adipocytes in Korean native calves. Twenty female newborn calves [day 0 of age; initial BW: 31.2 kg (SD 3.07)] were stratified based on whether they received vitamin A supplementation during the early fetal to neonatal stages, and then randomly allocated to four groups using a 2 × 2 factorial arrangement. Vitamin A supplementation was conducted as follows: fetal stage (control: 7,800 IU/kg of as-fed, treatment: 22,800 IU/kg of as-fed); neonatal stage (control: 17,000 IU/day, treatment: 53,000 IU/day). Growth performance, blood variables, mRNA expression in muscle tissue, and muscle fiber diameter were evaluated during the experimental period and analyzed using the MIXED procedure with Tukey's test by SAS 9.4 software. As a result, fetal-vitamin A treatment group exhibited higher (P &lt; 0.05) serum vitamin A concentrations and blood glucose concentrations on the day 3 of age. Similarly, vitamin A supplementation in the neonatal stage significantly increased (P &lt; 0.05) serum vitamin A concentrations at day 30 and 60 of age, as well as albumin and glucose concentrations at day 60 of age. Moreover, both birth and weaning BW were significantly greater (P &lt; 0.05) in calves receiving vitamin A supplementation during the fetal stage. However, feed intake and muscle fiber diameter showed no differences (P &gt; 0.05) between the groups. In addition, supplementation of vitamin A during the fetal stage resulted in upregulation (P &lt; 0.05) of ZNF423 mRNA expression in the longissimus dorsi muscle, whereas neonatal supplementation upregulated (P &lt; 0.05) the mRNA expression of PAX7 and MYF5. Our findings suggested that vitamin A supplementation during the early fetal to neonatal stages can enhance the growth performance of offspring calves and potentially promote an increase in pre-adipocyte and satellite cell storage in muscle tissue. This information can be applied in integrated fetal-neonatal nutrient feeding strategies in beef cattle.
37 Precision Feeding of Prolific Sheep in Highly Productive Management Systems
Authors: Ehrhardt Richard A , Barbara Makela 
Published: November 2023

Abstract
Globally lamb production is constrained by seasonal reproduction and flock productivity. There is potential to reduce both with improved reproductive and nutritional management in systems with a reduced interbirth interval. These accelerated systems can improve productivity &gt;2 times compared with conventional systems. Successful adoption of these systems has been hampered; however, by low and variable reproductive efficiency during the suboptimal breeding period (February to July). We designed a series of studies to address this problem using an 8-month birth interval system with Polled Dorset x Polypay ewes without the use of exogenous hormone or photoperiod therapies. In study 1, we examined prebreeding nutrition combined with the male effect on reproductive outcomes in both long (April/May) and short-day (Dec./Jan.) breeding seasons. Ewes were randomly allocated to one of 3 nutritional treatments after weaning during a 21-day prebreeding period: 50%, 100% or 200% of maintenance energy intake. Ewes were exposed to vasectomized rams the last 14 days of treatment followed immediately with fertile rams for a 34-day breeding period (22 to 27 ewes per vasectomized or fertile ram). Both litter size (1.60 short vs. 1.34 long) and conception (96% short vs. 86% long) were greater in the short season (P &lt; 0.001). Nutrition did not impact conception in either season; however, litter size was increased 15% in long and 25% in short day breeding season in ewes fed 200% compared the other treatments. These results suggest that litter size can be improved in these systems regardless of season by elevating energy intake above current recommendations. In study 2, we examined the impact of energy status during 2 preconception periods: lactation (last 30 days of previous lactation) and flushing (21 days pre-breeding plus 34-day breeding period). During lactation ewes received either 70% (L), 100% (C), and 150% (H) of energy requirements according to litter size. During flushing, ewes received 70%, 100% and 160% of maintenance energy with reproductive management as for study 1. Blood samples collected every 3 to 4 days were analyzed for plasma progesterone concentration via radioimmunoassay. Season had a great impact on return to estrus with 18% of ewes exhibiting luteal phases before teaser ram introduction during long as compared with 99% during short-day season. Nutrition during lactation also impacted return to estrus but only in long days with 40% of ewes on the H diet exhibiting luteal phases compared with 14% on the L diet before teaser ram introduction. Collectively, this indicates that an increased rate on conception is possible without the use of exogenous hormones or photoperiod manipulation in accelerated systems. Furthermore, a high plane of preconception nutrition improves litter size regardless of season and may hasten return to estrus during the suboptimal breeding period.
383 Effect of Feeding Ractopamine to Finisher Lard-Type Mangalica Pigs on Longissimus Muscle Fiber Myosin-Heavy Chain Isoform Expression and Cross-Sectional Area
Authors: Herrera Said J , Calderon Allan J , Pitts Megan Reeves , Smith Hunter R , Amerson Ellie , Anderson Brian L , Sawyer Jason T , Brandebourg Terry D , Starkey Charles , Starkey Jessica D 
Published: November 2023

Abstract
Heritage breeds such as Mangalica pigs are gaining popularity in US niche markets and currently sold as high-quality meat due to greater meat quality characteristics. Research has demonstrated that feeding the β-adrenergic agonist ractopamine hydrochloride (RAC), stimulates hypertrophic growth of type-2, fast-twitch glycolytic muscle fibers via mTOR signaling resulting in greater myofibrillar protein synthesis. Therefore, the current study evaluated the effect of feeding RAC to Mangalica pigs during the finisher phase on longissimus muscle fiber myosin heavy-chain (MHC) isoform expression and cross-sectional area. Mangalica pigs were randomly assigned finisher diets for 21 d with 20 ppm (RAC; n = 8) or without (CTL; n = 6). Longissimus muscle samples were collected during carcass fabrication, flash-frozen in liquid nitrogen and stored at -80 °C. Immunofluorescence staining of 5-µm-thick cryosections to identify Type-1 (Developmental Studies Hybridoma Bank (DSHB) antibody Ba-D5), Type-2a (DSHB SC-71), and 2x (DSHB BF-35) MHC positive fibers. Type 2b fibers were determined by subtraction. Fibers in each image (≥ 150) were assessed for fiber type and their cross-sectional area (CSA) at 200X magnification. Data were analyzed as a one-way ANOVA using the GLIMMIX procedure of SAS V9.4. Means were separated with the PDIFF option and declared different when P ≤ 0.05. Tendencies were declared when 0.0501 ≤ P ≤ 0.1000. Feeding RAC decreased the density of Type 2a (P = 0.0136) and Type 2b (P = 0.0186) fibers in the longissimus muscle of Mangalica pigs. A tendency for RAC to reduce the density of Type 1, slow-twitch (6.61 vs. 16.14 fiber per mm2; P = 0.0505) fibers and increase the density of primarily oxidative fibers expressing a combination of Type 1 + Type 2a MHC isoforms (10.23 vs. 2.88%; P = 0.0524) was also observed. When analyzed as a proportion of total fibers, RAC reduced the proportion of fibers expressing only Type 2a (11.8 vs. 6.70%; P = 0.0468) and Type 2b (0.19 vs. 1.32%; P = 0.0101) MHC isoforms but increased the percentage of fibers expressing both Type 1 + Type 2a MHC isoforms (4.66 vs. 1.13%; P = 0.0280). Feeding RAC did not impact the density or proportion of fibers expressing Type 2x MHC (P ≥ 0.386). Mean longissimus muscle fiber CSA was not impacted by feeding Mangalica pigs RAC for 21 d (P = 0.4815). The CSA of the smallest and largest fibers nor fiber distribution were influenced by RAC inclusion in the diet of Mangalica pigs (P ≥ 0.484). In conclusion, feeding RAC Mangalica pigs impacted fiber MHC isoform expression in the longissimus muscle without altering fiber CSA. Future studies will explore the impact of RAC on the CSA of the various fiber types as well as the impact on other muscles in the Mangalica pig.
74 Setting Students Up for Success in the Agricultural Industry
Authors: Oosthuizen Nicky 
Published: November 2023

Abstract
When asked about future employment goals, many agricultural students express interest in being employed in the industry following graduation. Even though a large number of students have this career path in mind, students are often not prepared for industry roles. The agricultural industry favors employees who have good soft skills, such as communication, teamwork, and interpersonal skills, as it is often required that employees collaborate within a team or connect with clients and colleagues. Nevertheless, these soft skills are often not taught or are not emphasized enough during undergraduate or graduate education as they are often difficult to teach in a classroom setting. International students face unique challenges when seeking employment as industry professionals. Some of these challenges, such as language barriers or social and cultural differences, can make important tasks, like networking, more difficult. There are opportunities for university faculty to assist students wanting to seek employment in the agricultural industry, such as by organizing networking events and establishing industry-focused classes or lectures. Networking in a professional setting is a vital skill for students trying to enter the industry; therefore, providing students with opportunities to practice networking and professional social skills among their peers and superiors is critical. Courses or lectures focused on understanding the industry and its challenges would also be highly beneficial to students, particularly those who do not come from agricultural backgrounds and those that are international. Encouraging students to take part in student organizations and extension events, and to apply for teaching assistant positions for relevant production classes may also contribute to student preparation for industry employment. By providing students with an overall understanding of the agricultural industry and opportunities to improve skills that are relevant for industry positions, faculty members may be able to improve student preparedness for these roles and assist in making students more marketable to individual companies.
401 Dietary Starch Dilution Strategies to Improve Feedlot Cattle Performance and Rumen Health
Authors: Kobza Anna M , Young James D , Richeson John T , Lawrence Ty E , Tennant Travis C , Samuelson Kendall L 
Published: November 2023

Abstract
This study evaluated starch dilution with different sources of fiber from terminal implant to harvest on feedlot cattle performance, rumen buffering characteristics, and carcass outcomes. Steers (n = 416) were allocated to 48 pens in a randomized complete block design and assigned to 1 of 4 dietary treatments. Treatments were steam-flaked corn-based diets: CON; 7.5% corn stalks fed for the entire feeding period or CON followed by CS; 14.8% corn stalks, WD; 9.5% wet distillers grains with solubles and 7.5% corn stalks, or NR; 19.0% wet distillers grains with solubles and 0.0% corn stalks fed from terminal implant to harvest. Steers were transitioned to CS, WD, and NR over 6 d using a two-ration system. Within each pen, 2 steers received an indwelling rumen pH bolus and a 3-axis accelerometer ear-tag to quantify rumination. Treatment differences were considered statistically significant when P &lt; 0.10. Dry matter (DM) and metabolizable energy (ME) intake were greatest for cattle consuming CS, intermediate for WD and CON, and least for NR (P &lt; 0.01). The average daily gain (ADG) did not differ among treatments (P = 0.18); however, feed efficiency (G:F) was least for NR, intermediate for WD, and greatest for CS and CON (P = 0.10). Steers consuming CS had more (P = 0.08) 12th rib fat than NR, WD, or CON, but no other differences (P ≥ 0.24) in carcass characteristics were observed. A treatment × day interaction (P &lt; 0.01) was observed for daily rumination time and ruminal pH. Results suggest that increasing the concentration of corn stalks in the diet post-terminal implant increased DM and ME intake and rumination; replacing corn stalks with wet distillers grains with solubles improved G:F and reduced rumination with minimal impacts on ruminal pH.
PSVI-17 Application of Stride Length to Assess Leg Soundness for Growing Gilt
Authors: Huang Hsiao-Han , Lin En-Chung , Lin Kai-Hsiang , Ting Shu Han 
Published: November 2023

Abstract
The durability of sows would be affected by their leg soundness. Problems of leg or lameness is the second reason for culling especially in the first three parities. Observing the leg structure during the growth period of pigs is necessary in selection programs because traits related to leg structure have intermediate to low heritability. However, long-term tracking of changes in feet and leg structure of pigs using quantitative measuring methods has not been conducted. Such measuring methods have not yet been applied on farms so far. Thus, this study aimed to use stride length data from pressure mat to evaluate leg soundness in growing gilts. A pressure mat system was used in this study to collect stride length (SL) data and ground reaction force (GRF) data of 23 purebred gilts at 4.5, 6.0, and 7.5 months of age. The SL data obtained in each pig was used to calculate the symmetry index with the SL records of the left and right legs for both front and rear. Similarly, the GRF data enabled the calculation of GRF symmetry index of the left and right leg of a pig for both front and rear. The confusion matrix was applied to compute the accuracy, sensitivity, and specificity by comparing visual inspection of gilt culling or the SL symmetry index to the GRF symmetry index as the standard. The accuracy, sensitivity, and specificity of visual inspection of gilt culling versus GRF symmetry index at 7.5 months of age were 80%, 31%, and 100%, respectively. Meanwhile, the accuracy, sensitivity, and specificity of the SL symmetry index versus GRF symmetry index at 7.5 months of age were 96%, 85%, and 100%, respectively. At 6.0 months of age, such accuracy, sensitivity, and specificity of the SL were 89%, 67%, and 97%, respectively. But, at 4.5 months of age, such accuracy, sensitivity, and specificity of the SL were 87%, 50%, and 97%, respectively. These findings suggest that visual inspection for leg soundness of gilt has limited capability to identify pigs with an asymmetry gait which might cause current and future leg problems. But the SL symmetric index shows better potential for that purpose that it will be a suitable objective measure to replace visual inspection for leg soundness in pigs.
PSVI-16 Conditioning Dairy Cows to a Virtual Fencing System Is Compatible with Animal Welfare
Authors: Fuchs Patricia , Stachowicz Joanna , Schneider Manuel , Probo Massimiliano , Bruckmaier Rupert M , Umstätter Christina 
Published: November 2023

Abstract
Virtual fencing (VF) enables livestock grazing without physical fences by conditioning animals to an audio tone (AT) followed by an electric pulse (EP) that is up to 25 times weaker than conventional electric fencing (EF). However, the operating principle of a virtual fencing system raises concerns about animal welfare. Therefore, the present study investigated the learning process of dairy cows in a virtual fencing environment and its effects on animal behavior and welfare. Twenty lactating cows were divided into four groups of five individuals each (2x VF; 2x EF), balanced by lactation stage (203 ± 62 days) and age (3.7 ± 1.5 lactations). All cows were accustomed to daily grazing with EF but were naïve to VF. Each group grazed in a separate paddock for 3 days of acclimation (P0) and 21, 14, 14, and 7 days of experimental treatment (P1-4). All paddocks were electrically fenced, and of similar vegetation structure and botanical composition. During P1-P4, a virtual boundary was activated within each paddock of the VF groups, and a second electric fence was set up within each paddock of the EF groups to maintain comparable paddock sizes. All cows were fitted with a VF collar (Nofence AS, Batnfjordsøra, Norway) and an IceQube pedometer (Peacock Technology Ltd, Stirling, UK). The sensors continuously tracked cow positions, the daily numbers of AT and EP, and activity behavior, respectively. Throughout P0-P4, daily milk yield, feed intake, and body weight were recorded. A total of 26 milk samples were collected per cow to determine milk cortisol concentrations. Behavioral observations were conducted for 2 h on 23 days to record agonistic behaviors, vocalizations, and excretions. During P1-P4, each cow received an average of 1.9 ± 3.3 AT and 0.1 ± 0.7 EP per day. The total number of stimuli ranged from 37 to 225 AT and 3 to 11 EP per cow throughout the experimental period, indicating individual variations in learning (P &lt; 0.003). Within the first three days after virtual fence activation, most cows learned the concept of the VF system. The conditioning of the cows was successful at herd level after three repetitions at a new virtual boundary, reflected by a decreasing ratio of mean EP/AT from 20 to 3, 2, and 0 % with each paddock change. Milk yield and cortisol, feed intake, body weight, and cow activity did not differ between VF and EF groups. Overall, there were a mean of 11.2 vocalizations and 5.9 displacements more per cow in the VF groups (P &lt; 0.05), but similar across P0-P4. Our results suggest that learning the virtual fencing system did not lead to lasting adverse effects on cow welfare.
PSVII-8 Genome-Wide Association Studies for Feed Efficiency and Growth Traits in American Mink
Authors: Davoudi Pourya , Do Duy Ngoc , Rathgeber Bruce , Colombo Stefanie , Sargolzaei Mehdi , Plastow Graham , Wang Zhiquan , Miar Younes 
Published: November 2023

Abstract
Feed efficiency (FE) traits contribute to the economic output of mink production systems as feed costs comprise the largest proportion of their variable expenses. However, the genetic architecture underlying FE-related traits is largely unknown in American mink. The objective of this study was to identify potential genetic variants and candidate genes associated with feed efficiency and growth traits, including body weight (BW), average daily gain (ADG), daily feed intake (DFI), feed conversion ratio (FCR), residual feed intake (RFI), residual gain (RG), residual intake and gain (RIG), and Kleiber ratio (KR). Genome-wide association studies (GWAS) were performed using deregressed estimated breeding values (DEBVs) of 1,255 to 2,160 individuals (as pseudophenotypes), genotyped with the Affymetrix Mink 70K single nucleotide polymorphisms (SNP) array. Association analyses were performed using the mixed linear model in GCTA software. A total of 36 SNPs located on 11 different chromosomes were significantly (FDR &lt; 0.01) associated with eight feed efficiency and growth traits, among which nine SNPs had pleiotropic effects on at least two analyzed traits. The phenotypic variance (of DEBVs) explained by all significant SNPs for BW, ADG, DFI, FCR, RFI, RG, RIG, and KR, were 0.54%, 2.35%, 0.51%, 2.45%, 0.03%, 3.67%, 0.21%, and 2.60%, respectively. Furthermore, 191 genes were identified within 1-Mb windows around these significant SNPs. These regions included candidate genes such as FABP6, ADAMTS18, ADGRB3, GRM8, DSCAM, COL9A1, and CSRP2, previously associated with feed efficiency and growth traits in other livestock species. Gene ontology analyses revealed that these genes were involved in molecular functions such as ATPase activity and ATP binding, which provide the direct energy source for the body. To our knowledge, this is the first GWAS to identify genetic variants and biological mechanisms associated with FE and growth traits in American mink. These findings provide a biological foundation for improving these traits using genomic selection programs to select more efficient mink.
PSXII-4 Genomic Improvement of Disease Resistance Using Two Breeding Strategies in a Population of Penaeus Vannamei (Pacific White shrimp): a Simulation Study
Authors: Ampofo Issabelle , Kobayashi Julian , Miller Clara , O'Neil Shauneen , Dhar Arun , Fragomeni Breno O 
Published: November 2023

Abstract
This study aimed to investigate the impact of SNP density chip and genotyping strategies on the accuracy of genomic estimated breeding values (EBV) in a simulated population mimicking a commercial Pacific white shrimp (Penaeus vannamei) breeding program. The chromosome number and length mimicked the P. vannamei genome. To create an initial linkage disequilibrium (LD), a historical population of 5,000 animals was randomly bred for 1,000 generations and included a bottleneck on generation 750. In the last generation of the historical population, animals were randomly selected to create a breeding population with an effective population size (Ne) of 40. From the breeding population, a total of 40,000 animals were simulated over 20 generations. Phenotypes for a trait with a heritability of 0.1 was simulated, and genetic variance was 100% explained by 1,000 QTLs. Phenotypes and genotypes were saved for all animals in the last 10 generations, while pedigree from all 20 generations was used. To mimic the selection of young animals, a forward-in-time prediction was implemented by masking the phenotypes from the 20th generation in the data analysis. The accuracy of prediction was the correlation between the simulated true breeding value and the EBV in the last generation. Genomic information consisted of SNP chips with 6K, 11K, 22K, 45K, and 90K markers evenly spaced across the genome. The two breeding strategies considered in this study were 1) 25 families with 40 animals each, and 2) 50 families with 20 animals each. Additionally, the number of generations with phenotypes varied from nine to one. This was done to identify the minimum number of generations to collect data, as phenotyping individuals may be challenging in aquaculture. In all scenarios, genomic selection outperformed family selection. Results indicated that genotyping more individuals within families, instead of more families with fewer individuals, improved the accuracy of predictions. Furthermore, the maximum accuracy was achieved with 45K and 90K SNPs in both scenarios, showing that SNP density will reach a plateau. Finally, maximum accuracy plateaued at five generations. Finally, having one generation with phenotypes and genotypes yielded greater accuracies than nine generations with only phenotypes. Overall, the results from the present study suggest that genomic selection using the single-step genomic best linear unbiased prediction (ssGBLUP) methodology is a feasible tool to improve P. vannamei commercial populations, even for traits with low heritability. Moreover, it is recommended to collect data on more individuals per family than increasing the number of families, and data collection should be continued for at least four generations. Tests with real data will provide further insights into the ideal number of animals and SNP density necessary for maximum accuracy.