bluuebunny/crossref_metadata_2025 huggingface dataset:
335 Use of Feed Additives Added to the Milk Replacer and Concentrate Or Only to the Concentrate in Unweaned Dairy Beef Calves After Transportation and Its Effects on Performance
Authors: Marti Sonia , Blanch Marta , Devant Maria
Published: November 2023

Previous studies have shown that the use of additives to enhance intake and immunity at farm arrival could be a strategy to minimize the negative effects of stress and feed restriction during transportation in unweaned calves. Unweaned dairy beef calves are fed low liquid feeding programs to avoid mechanical diarrheas and to enhance the consumption of solid feed to increase growth. A total of 78 dairy beef calves (57.8 ± 1.64 kg) coming from auction market were used to evaluate the effect of various feed additives [FA; comprising palatability enhancers (PE), standardized olive pomace extract (OE), and tributyrin (TB)] added to the milk replacer (MR) and concentrate or only to the concentrate on performance until 1 week after weaning. Calves were distributed in 6 treatments: calves fed MR and concentrate without FA (CTR-CTR; n = 13); calves fed MR without FA and concentrate with PE (CTR-PE; n = 13); calves fed MR without FA and concentrate with complete mixture OE + TB + PE (CTR-COM; n = 13); calves fed MR and concentrate with PE (PEPE; n = 13); calves fed MR with PE and concentrate with complete mixture OE + TB + PE (PE-COM; n = 13); calves were fed MR with complete mixture OE + TB + PE and concentrate with PE (COM-PE; n = 13). At arrival calves were only fed 2 L of MR twice daily at 12.5% and concentrate feed ad libitum. On day 35 of the study, animals were submitted to a social stress challenge, calves within one treatment were mixed for 24 h, and on day 36, calves returned to their home pens and the afternoon milk was removed. On day 42, all calves were weaned, and they were followed until day 49. Data were analyzed with a mixed-effects model. No differences were observed in concentrate intake the first week after transportation. However, an interaction between treatment and time (P < 0.01) was observed among treatments in concentrate intake from day 35 until day 49 when calves were already weaned. The PE-PE and PE-COM calves had a greater (P < 0.10) concentrate intake from day 28 to day 42 than CTR-CTR or CTR-PE calves, while from day 42 to day 49 the CTR-COM was the group of calves with the greatest concentrate intake. Although no differences were observed on final BW among treatments, the CTR-COM calves had numerically greater ADG than the rest of the treatments. In unweaned dairy beef calves with liquid feeding restriction, the mixture of palatability enhancers, standardized olive pomace extract, and tributyrin potentially increases concentrate intake and growth when added in the concentrate feed.
325 Understanding Variation in Residual Feed Intake of Brahman Steers Fed Two Different Diets
Authors: Silva Luis Prada e
Published: November 2023

Improving feed efficiency in cattle is a long-standing aim of the beef industry. However, discrepancies in the ranking of bulls based on the diets used and calculation methods employed for defining feed efficiency have been observed. Hence, the objective of this research was to assess the extent to which different factors influence feed efficiency in Brahman steers. Individual DMI and ADG were measured, and residual feed intake (RFI) calculated using linear regression of DMI on ADG and midtest metabolic body weight. Eight-nine steers were initially fed a low-protein diet (LP, 8.8% CP) for 70 days, followed by a high-protein (HP, 13.5% CP) diet for another 70 days. The genetic variation among steers and the proportion of Bos indicus genes were determined using the GGP Indicus 50K assay (Neogen Corporation, Ipswich, Australia). Rumen bacteriome variation was determined with 16S rRNA gene sequencing of rumen fluid collected before and after feeding. Daily diet refusals were visually scored for the proportion of pellets versus hay and expressed as a diet selection index (1 to 3). Organic matter digestibility (OMD) was determined using total feces collection in metabolism crates. Plasma urea nitrogen (PUN) was measured in blood samples collected at four time points. The diet-animal fractionation of nitrogen isotopes (Δ15Ntail hair) was quantified in tail hair using isotope-ratio mass spectroscopy to indicate differences in nitrogen metabolism. Finally, carcass characteristics were determined at slaughter. Including carcass fat depth improved (P = 0.01) DMI prediction (R2 increased from 78.4 to 80.4%) in the LP diet but had a smaller effect (P = 0.39) in the HP diet (R2 increased from 75.0 to 75.2%). In the LP diet, the variation in carcass fat-correct RFI (RFIc) could be explained by DMI (14.5% of the variation), rumen bacteriome (5.89%), diet selection index (3.08%), PUN (1.88%), genetic distance (0.76%) and OMD (0.50%), accounting for a total of 26.6% of the RFIc variation. In the HP diet, the regression model explained 35.3% of the RFIc variation, with DMI explaining 25.9%, diet selection index 7.19%, rumen bacteriome 1.02%, genetic distance 0.73% and Δ15Ntail hair 0.50%. In conclusion, this study highlights the importance of measuring diet selection to accurately determine RFI in cattle. The results also suggest that variations in the rumen bacteriome and nitrogen metabolism parameters play a role in individual variations of feed efficiency. However, most of the variation in feed efficiency remained unexplained.
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

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 < 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 < 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 < 0.05) in calves receiving vitamin A supplementation during the fetal stage. However, feed intake and muscle fiber diameter showed no differences (P > 0.05) between the groups. In addition, supplementation of vitamin A during the fetal stage resulted in upregulation (P < 0.05) of ZNF423 mRNA expression in the longissimus dorsi muscle, whereas neonatal supplementation upregulated (P < 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

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 >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 < 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

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

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

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 < 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 < 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 < 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

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

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 < 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 < 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

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 < 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

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.
PSIV-26 Development of a Controlled Exposure Particulate and Oxidative Radical Mask for Causality Experiments Investigating Smoke Exposure on Livestock Animals
Authors: Brody Tio , Franco Arturo Macias , Silva Aghata , Holton Graham , Mazza Pedro , Fonseca Mozart A
Published: November 2023

Understanding and mapping the specific effects of smoke inhalation on cattle performance provides strategic insights for producers and policy makers to better prepare or adjust when faced with sporadic or even seasonal reductions in air quality. As of now, no current studies have attempted to investigate the effects of seasonal fires on performance and health adequately in livestock while addressing obvious confounding effects, controlling exposure, and examining fuel for differential oxidative radicals and particulate smoke. Herein, we propose the design of the first cost-effective controlled system for investigating smoke, particulate matter, and varied oxidative radicals through a pre-mixing chamber. The mask main body is constructed from 8” nominal diameter schedule 40 PVC pipe. The endcap was designed in an online CAD software to provide an interface for standard 2 ⅞” bulkhead fittings and was produced via additive manufacturing (3D printing). A silicone SCUBA neck seal was used to line the face orifice and is the component that directly contacts the animal’s nose and mouth. A neoprene rubber sheet and an insulation hose were used as padding under the silicone seal to help maintain an airtight connection and animal comfort when the mask is worn. Bulkhead fittings used provide 1 ½” female national pipe thread connection to allow for modular connection of inlet and outlet hoses, check valves for airflow isolation, filters, or any number of connections can be made via these gasket sealed fittings, making this platform extremely adaptable. In its shown configuration, 3D printed adapters were made to attach 4” suction hose to 2” socket union joints for quick connect/disconnect functionality. An inlet and outlet gas/smoke flow regulator are attached to a mixing chamber where particulate and chemical composition sensors are utilized to deliver the desired composition of smoke delivered to the animals. Negative pressure fans and pumps regulate the flow to the animals and are utilized for exposure of smoke in time-specific intervals. An additional fully 3D printed version enables the mask design to be lower in weight through regulation of the density of the internal matrix, and after an initial investment in the equipment also represents a cost-efficient approach to generating multiple masks. Understanding the effects of particulate and reactive oxidative molecules on livestock health and performance requires the study of a controlled exposure, the system presented herein represents a viable and cheap alternative for bettering a mechanistic model and understanding of the effects of smoke on animal health and performance. Ultimately, the proposed mask paired with currently available sensors permit for the controlled exposure of smoke particulate with different chemical compositions for accurate evaluation of prolonged exposure effects on livestock.
PSI-10 Prioritizing Fertility-Related Genes in Cattle Through Systems Genomics Data Integration
Authors: Kertz Nicholas C , Banerjee Priyanka , Afonso Juliana , Dyce Paul W W , Da Silva Diniz Wellison Jarles j
Published: November 2023

Female fertility significantly affects the efficiency of cow-calf production. Despite the collective efforts to understand the complex regulation of reproductive traits, causative genes and/or mutations have yet to be reported. Using omics technologies, such as gene expression, may unveil potential regulatory mechanisms and provide opportunities that link genotype to phenotype. Among them, expression quantitative trait loci (eQTL) are a powerful tool to identify biological mechanisms and potential markers for improving fertility. This study aimed to identify eQTLs underlying fertility-related traits and their co-localization with previously annotated QTLs. RNA-Seq from uterine epithelial cells (GSE171577) from crossbreed cows (n = 18 non-pregnant – NP and n = 25 pregnant – P) were used for gene expression analysis and SNP calling. Raw data quality control was performed, and read mapping was carried out using STAR. Genes were normalized to counts per million (CPM) and then the CPM values were log2 transformed using edgeR. Next, uniquely mapped reads were used for variant detection using the GATK software. Significant eQTLs were compared with the Animal Genome cattle database (QTLdb) to identify overlapping QTL regions. After quality control, 43 samples, 203,404 SNPs, and 15,029 genes were used for eQTL analysis. Using an additive linear model from the Matrix eQTL R-package, we identified 3,989 cis- and 7,683 trans-eQTLs for 1,120 and 2,503 genes, respectively (FDR < 0.05). A total of 50 cis-eQTLs were previously reported as differentially expressed genes, including CD37, CXCL3, PILRA, and PPP6R1 genes. The QTLs from QTLdb overlapping with our eQTLs were associated with traits such as age at puberty, conception rate, fertility index, and luteal activity (FDR < 0.05). Additionally, QTLs for production traits, such as milk production and body weight gain, were over-represented by the eQTLs we have identified. Significant biological processes underlying cis-regulated genes retrieved from ShinyGO were related to antigen processing and presentation. Likewise, trans-eQTLs genes were involved with transcription cis-regulatory region binding and transcription regulator activity. Our study provides novel regulatory and potential causative genetic variants, biological pathways, and genes underlying fertility in cows. Annotation and co-localization of detected eQTLs retrieved genomic regions previously reported as QTLs for production and reproduction-related traits. Further investigation, however, is required to untangle the mechanisms modulating gene expression and its effects on fertility-related traits.
PSI-2 Evaluation of Sorghum Pericarp Varieties on Blood Parameters and Antioxidant Capacity in Healthy Adult Dogs
Authors: Bailey Katelyn , Alverenga Isabella Corsato , Aldrich Charles G G
Published: November 2023

Ingredients that provide health benefits are popular in the pet food industry. Sorghum contains polyphenols which are found in the pericarp. These polyphenols may provide health benefits due to their antioxidant properties, which increase the benefit of sorghum in pet food. Few pet food studies have evaluated the antioxidant capacity of sorghum differing in pericarp color. The objective of this study was to evaluate the effect of sorghum varieties on blood parameters and antioxidant capacity in dogs. Nutritionally complete experimental diets were extruded with a 50% inclusion of either rice, white sorghum A, burgundy sorghum, or white sorghum B. Twelve dogs were fed dietary treatments in a replicated 4 x 4 Latin square design consisting of 14-day periods. Three milliliters of blood were taken from each dog prior to starting the trial for baseline antioxidant capacity. At the end of each period, 3 mL of blood were taken from each dog and stored at -80°C until further analysis. Blood samples were analyzed for complete blood count (CBC), chemistry profiles (Kansas State University Veterinary Diagnostics Lab, Manhattan, KS), and oxygen radical absorbance capacity (ORAC) was measured by kit in blood plasma. Data were analyzed using a mixed model with statistical analysis software (SAS version 9.4, SAS Institute, Inc., Cary, NC) with treatment and period as fixed effects and dog as a random effect. Red blood cell distribution width was greatest in dogs fed white sorghum A at 12.9% and least in dogs fed white sorghum B at 12.7% (P < 0.05). The anion gap was highest for dogs fed the rice treatment at 24.6 mmol/L and lowest for dogs fed white sorghum A at 22.8 mmol/L (P < 0.05). Cholesterol was greater (P < 0.05) in dogs fed the rice treatment at 246.0 mg/dL compared with the three sorghum varieties (average, 225 mg/dL). Despite the few differences in blood parameters, all were within normal ranges for healthy dogs. There was no difference in plasma ORAC between treatments (P > 0.05). In conclusion, sorghum resulted in normal blood profiles and did not alter plasma antioxidant capacity compared with the rice control when fed to dogs. If antioxidant potential is desired, a concentrated pericarp (bran) extract may be necessary.
PSIII-6 Impact of Aromatic Palatants on Equine Feeding Preferences
Authors: Crowell Cierra N , Handlos Grace , Perry Erin B , Discepolo Dakota R
Published: November 2023

Although flavored palatants are commonly utilized in feed manufacturing, few data were available regarding the impact of aromatics on equine feeding preferences. The objective of this study was to investigate the effects of aromatic palatants on feeding behaviors of lactating mares and nursing foals. Four quarter horse mare and nursing foal pairs were used in this paired preference test. Horses were group-housed with ad libitum access to pasture (cool season grass/legume mix), water and mineral salt. Pairings were tested for four consecutive days, with eighteen days off between each testing series, for a total trial of ten-weeks. Testing occurred from 1630-1730 h each day. Treatments were offered in false bottom pans constructed with twenty-four equally spaced openings (0.19 cm) and one (0.48 cm) central opening to allow odor permeation. Aromatic treatments, in powdered form (anise, apple, and peppermint), were placed within single use plastic containers nested underneath the feeding pans. Feed pans were spaced two inches apart and affixed to a flat, wooden platform with treatment location changed daily. Video was recorded and analyzed for first treatment investigated, consumed, and finished of pairs. Further analysis investigated the time spent consuming treatments and voluntary consumption of foals. Statistical analysis was performed (SAS for Academics, 2014, Cary, NC, USA) with significance set at 5%. The aromatic treatments utilized in this study yielded similar selective actions of mares for first investigated (P = 0.8472), consumed (P = 0.8472), and finished (P = 0.8166). Similarly, foal actions for first investigated (P = 0.5206), consumed (P = 0.5206), or finished (P = 0.1650) were not affected by aromatic treatments. There was a significant relationship between mare and foal first aromatic treatments investigated (P = 0.0415; R2 = -0.262) and consumed (P = 0.0415; R2 = -0.262) suggesting that different treatments were selected between the pairs (Table 6.2). A strong relationship was observed for first investigated and first consumed aromatic treatments of mares (P < 0.0001; R2 = 1.00). However, foals were found to remain with the first investigated aromatic treatment for first consumed (P < 0.0001; R2 = 1.00) and first finished treatments (P < 0.0001; R2 = 1.00). The mean voluntary consumption of concentrate was unaffected by treatment (P = 0.6646) and no period effect was observed (P = 0.1854). Mean time spent consuming was also unaffected by treatments (P = 0.1003) with no period effect observed (P = 0.4903). Despite no differences in the amount consumed, there was a greater time spent consuming peppermint treatments (257.97 ± 103.03 seconds) compared with that of anise (148.85 ± 84.09 seconds) and apple treatments (139.23 ± 77.00 seconds).
PSIII-11 Effects of Inoculation of Alfalfa Hay with Pediococcus Pentosaceus and α-Amylase on Hay Temperature, Microbial Ecology, Nutrient Composition, and Feed Value
Authors: Kaplan Daisy , Bien Richard A , Embaby Mohammed , Skidmore Andy , Patterson Wade , Perry Erin B , AbuGhazaleh Amer , Bender Kelly , Nair Jayakrishnan
Published: November 2023

Haying in the Midwest is challenging, with excessive spring and early summer precipitation followed by unpredictable rain events throughout the growing months, forcing farmers to be innovative and resort to novel haying practices. High moisture haying with lactic acid bacterial (LAB) inoculants allows farmers to harvest earlier with less expenditure. This study examined how inoculating high-moisture alfalfa hay with Pediococcus pentosaceus and α-amylase (Magniva for Hay; Lallemand Animal Nutrition, Milwaukee, WI) affected hay temperature, microbial ecology, nutritional content, and feed value. Alfalfa was harvested at the late flowering stage and allowed to wilt in windrows for two days until the moisture level dropped to 20-25%, at which point half of the field was baled (20 bales) with the inoculant at 1.25 L ton-1, providing 1.0 × 106 cfu g-1 fresh forage of Pediococcus pentosaceus (NCIMB 12675) and 2.5 × 106 units of α-amylase (INOC). Uninoculated alfalfa baled at 15–18% moisture (20 bales) served as control (CON). The hay bales were stored under cover and sampled using a hay corer on days 0, 60, 120, and 180 to evaluate nutrient composition, microbial ecology, and feed value. Dallas Thermochron iButton sensors (Embedded Data Systems, Lawrenceburg, KY) were inserted into the center of hay bales during day 0 sampling (20 sensors per treatment) to measure the temperature every 4 h over 180 days. The core holes were air-tightened with alfalfa hay after installing the iButton sensors. SAS (SAS Institute Inc., 2012) mixed model technique was used to assess repeated measurements with treatment (T), day (D), and T × D effects. CON had greater LAB counts (log10 cfu g-1 DM) than INOC (7.45 vs. 7.11; P = 0.03) during storage. On days 0, 120, and 180 of storage, INOC had lower yeast counts (P < 0.02) than CON (T × D interaction). INOC exhibited higher core temperatures (P < 0.03) than CON on days 14, 21, and 28 of storage, peaking at 46.7°C on day 14. INOC reported lower DM than CON on days 60 and 120 of storage (P < 0.03). INOC had a higher CP concentration (18.0 vs. 16.9; P < 0.0001) than CON throughout storage. On days 60, 120, and 180 of storage, INOC had increased ADICP and NDICP (% DM) concentrations than CON (P < 0.05). Results indicated that inoculation of high moisture alfalfa hay with LAB inoculants is a viable alternative for farmers in the Midwest severely impacted by unpredictable weather events due to global warming. Further studies will provide detailed information on nutrient degradability and utilization for livestock production.
PSV-9 Cold Exposure Impacts Dna Methylation Patterns of Genes in Cattle Sperm Involved in Early Embryonic and Bone Development
Authors: Hossain Md Nazmul , Gao Yao , Hatfield Michael J , de Avila Jeanene M , McClure Matthew C , Du Min
Published: November 2023

DNA methylation and other epigenetic modifications are indispensable for maintaining sperm quality, fertilization capacity, and embryonic and postnatal development. In mice, environmental factors, such as stress, nutrition, or exposure to the cold condition, have been demonstrated as factors that alter methylation marks of sperm that are passed to the subsequent generation through transgenerational inheritance and genomic imprinting. Breeding bulls from northern regions of the USA are exposed to extreme cold for 2 to 3 months during the winter; however, no single study has analyzed the consequences of this cold exposure on the methylation pattern of bull sperm, which constitutes a significant knowledge gap. Therefore, this study aimed to explore the effects of cold exposure on the overall and gene-specific methylation status in sperm. We collected semen from 5 bulls during winter seasons after cold exposure and at normal temperatures during late spring. Whole Genome Bisulfite Sequencing (WGBS) was conducted to obtain the DNA methylation profile of these semen samples and to identify unique genes that have differentially methylated regions due to cold exposure (Figure 1). Cold exposure did not change the overall methylation level between the two groups but induced 438 Differentially methylated regions (DMRs) that overlapped with promoters, introns, exons, intergenic regions, shores, and shelves of CpG island (CGI) in 186 unique genes. We also identified nine unique differentially methylated genes (DMGs) (Pax6, Macf1, Mest, Ubqln1, Smg9, Trappc9, Ctnnb1, Lsm4, Peg10) involved in embryonic development and nine unique DMGs (Prmt6, Nipal1, C21h15orf40, Slc37a3, Fam210a, Raly, Rgs3, Lmbr1, Gan) involved in osteogenesis (Table 1). DMRs were located in the promoter regions and introns of these genes which preferentially involve gene silencing and alternative splicing. Among the DMGs involved in embryonic development, Mest and Peg10 are two paternally imprinted genes where only the paternal allele expresses. Peg10, required for optimal placental growth and trophoblast proliferation, overlapped with a hypermethylated DMR in the promoter region. Mest, another paternally imprinted gene, the downregulation of which results in embryonic growth retardation, had hypermethylation in introns. Moreover, Methylation-specific PCR (MS-PCR) verified the methylation changes in the identified regions. It was the first study to investigate the effect of cold exposure on DNA methylation of cattle sperm and suggest its association with altered sperm DNA methylation profiles. Differential methylation appears to alter gene expression and affect early embryonic development, osteogenic activity, and overall offspring growth performance through the imprinting effects.