bluuebunny/crossref_metadata_2025 huggingface dataset:
414 Design thinking for engaged learning (DTEL) in animal science: Data-driven considerations to improve student and instructor experiences
Authors: Brandão Alice P , Dunlap Kathrin , Wiegert Jeffrey , Paudyal Sushil
Published: September 2024

Design thinking for engaged learning (DTEL) is a framework developed to structure learning experiences based on collaborative project-based instruction and to engage students in creative problem solving. Despite being successful in providing meaningful learning experiences, the logistics of DTEL implementation can be difficult, especially in large courses (100+ students). Research is warranted to elucidate and facilitate DTEL utilization in different disciplines. Based on this, the present study utilized a design-based research approach involving 5 semesters of implementing DTEL in an animal science capstone course. Briefly, the main learning objectives of the course were for students to develop skills in collaborative work, independent research, communication (written and oral) and, especially, to be able to demonstrate transferrable knowledge from their previous coursework. Across 5 semesters (spring 2021 to spring 2023), student reflections assignments (n = 276) were coded and analyzed qualitatively to identify aspects that worked well or that students struggled with. Network analysis was utilized to visualize relationships (P < 0.05; Q > 0.4) between codes representing strengths, struggles, and alignment with principles from learning theories. Utilizing the relationships between strengths and theory-based principles to address struggles, resulted in changes to the design of the capstone course each semester, consecutively. Alignment of student experiences with principles from learning theories grew from the first semester to the last (theory-related nodes representing 11.4% vs. 24.4% in each network map, respectively), with learning theories also occupying more central positions in the map resulting from the last semester analysis (spring 2023) compared with earlier ones (spring 2021 through fall 2022). These changes suggest student experiences increasingly aligned with principles of cognitive constructivism, social constructivism, constructionism, situated learning, and transformative learning. Additionally, the analysis of students’ reflections throughout these 5 semesters of animal science senior capstone resulted in generalizable design principles to facilitate the implementation of DTEL in other animal science courses, especially in large class sizes (100+ students). The design principles derived from this 5-semester study include: 1) allocating most time to hands-on lab work versus lecture, 2) designating a coordinator faculty, 3) scaffolding for instructors unfamiliar with DTEL, 4) emphasizing consistency in processes over grades, and 5) intentionally developing teamwork skills. The study demonstrates the value of design-based research for iteratively refining and studying learning experiences to foster critical skills for undergraduate students in animal science.
410 Preparing yourself, or your students, for a career in the animal science industries
Authors: Elrod Charles C
Published: September 2024

Preparing yourself, or your students, for a career in Animal Science related industries may seem to require a crystal ball. As important as the specific knowledge might seem, the animal science students of tomorrow will need skills, perspective, an open mindset, the ability to think critically and a desire to be a problem solver. Careers going forward will reward the polymaths who are adaptable and resilient. Experiential training, a hallmark of animal science teaching in recent decades, should, in future, cross three domains: research, animal management and work. Experience in identifying pertinent research questions, forming hypotheses, a plan to test them and skills to analyze the results will be crucial to solving livestock-related challenges of the future. Living the day-to-day experience of a livestock producer will create graduates who are better grounded in and empathetic to the reality of livestock management. And lastly, internships can provide great insight into the demands of, and varied skills required to succeed in, the workplace. Our curricula for the animal science employee of the future should have depth and a great deal of breadth. Excellent understanding of the basic sciences: chemistry, biology, physiology, microbiology, is a given in order that employees can grasp the ever-deeper level of knowledge we have of animal-based systems. In our view, careers of the future will also require working knowledge of a wide swath of disciplines. Students should recognize the increasing likelihood that they may work in a small, entrepreneurial business at some point in their career. In addition to their animal science expertise, they may be called upon to contribute to initiatives in marketing, finance, innovation, global trade, data analytics, communications, One Health, compliance, sustainability or business ethics, to name a few. At the risk of being labeled as a “jack of all trades and master of none”, the animal science employee of the future will need multiple skillsets, the flexibility to draw on all of them and the willingness to step up and contribute to the success of their employer.
PSII-4 How to define good mothering ability using computer vision of free farrowing sows?
Authors: Lei Huaigang , van der Zande Lisette , Grindflek Eli , Hildebrand Madison , Dallago Gabriel
Published: September 2024

In modern swine production, most of the sows are housed in a cage system in the farrowing unit. Although this system is intended to reduce preweaning mortality, the welfare of the sow might be compromised as it greatly restricts their natural behavior. Free farrowing systems allow sows to move around in the farrowing pen, which might stimulate their nesting behavior, shorten the farrowing duration and improve locomotion score, therefore, optimizing the longevity of the sows. However, the risk of increased preweaning mortality in free farrowing systems is greater compared with cage systems. Previous studies suggested that sow behavior, also known as mothering ability, can influence preweaning mortality as an increased level of posture changes could lead to increased mortality. With grunts, a sow could initiate the suckling of the piglets but also terminate it by hiding her udder from the piglets. However, there is conflicting evidence on what characteristics of maternal ability are correlated with piglet mortality, and most studies relied on limited manual observations, which might be biased. Using computer vision algorithms, the behavior and the movement pattern of a large number of sows could be monitored at a high density and on a continuous basis. Hence, this study intended to investigate the mothering ability of sows in free farrowing systems based on large quantities and unbiased observations using computer vision. Forty cameras were installed above free farrowing pens to observe the behavior of the sow. The dataset is continuously growing and will add data of 8 sows every week, totaling 416 sows on a yearly basis. The performance of the sows and their piglets are recorded, including body weight (BW), backfat, total number born, number weaned, birth weight, and weaning weight. Computer vision algorithms (YOLO) will be trained to estimate the contour and posture of the sow and the position of the piglets. Preliminary results based on a small subset of animals showed that the algorithm is able to detect the sows and their postures accurately, and it is now being extended to detect piglet locations. This will allow us to find beneficial behavior of sow and piglets, estimate genetic parameters for potential implementation in breeding programs, and eventually improve sow performance in a welfare-friendly free farrowing system.
PSVII-3 Genome-wide association study for first-lactation fertility traits in dairy cattle
Authors: Seto Desiree , Chen Kevin , Campos Fernando , Peterson Dan , Sargolzaei Mehdi , Anderson Paul , Abo-Ismail Mohammed
Published: September 2024

Infertility has been a leading cause of economic loss for the dairy industry. It accounts for a total net loss of $259 per poor fertility cow per year compared with a cow with optimal fertility due to decreased milk production, non-pregnant cows, the inability to sell calves, wasted AI, and management costs. Thus, the goal of this study was to perform genome-wide association studies (GWAS) to identify significant single nucleotide polymorphisms (SNPs), genes, and biological pathways associated with age at first calving (AFC), calving ease (EASE) and interval from calving to first time bred (CFSI), and of first-lactation cow. The GWAS was performed on medium (100k SNPs) and high-density (700k SNPs) SNP panels on 2,121 Holstein and Jersey cows from three dairy herds in California. For each trait, univariate single SNP mixed model association analysis, implemented in GCTA software, was performed including breed and herd year interaction as fixed effects and the animal as random effect. The SNP was declared significant at a 5% false discovery rate (FDR) and on a suggestive level of significance for the top 100 significant. Two SNPs on chromosomes 18 and 21 were detected significant at 5% FDR for CFSI. Chromosomes 3, 10, 18, and 25, were found to hold associated regions from 100K. In-silico functional analyses were performed on the mapped genes using DAVID software to identify associated biological mechanisms and pathways. The enriched biological pathways were found to be regulation of plasma membrane organization (P = 0.016) for AFC, regulation of blood circulation (P = 0.03) for CFSI, and chemotaxis (P = 0.004) for EASE. The plasma membrane contains specialized domains abundant in sterols, a component previously shown to allow sperm to fertilize. Establishing blood flow to the reproductive tract is vital as it is the sole pathway of nutrient transport, and increasing blood circulation is needed to support fetal growth. A previous study confirmed a link between chemotactic activity of placental tissue and placental expulsion. These results will be further validated in relatively unrelated populations.
PSVII-4 A novel deletion in exon 3 of the myostatin (MSTN) gene is identified in a Raramuri criollo cattle herd
Authors: Rodríguez-Almeida Felipe A , Floriano-López Adriana , Martinez-Quintana Jose A A , Sifuentes-Rincón Ana M A , Felix-Portillo Monserrath , Jahuey-Martínez Francisco Joel , Sandoval-Villalobos Jesús , de la Cruz Gilberto Ruiz-
Published: September 2024

Several polymorphisms in the coding region of the myostatin (MSTN) gene have been associated with the double-muscled (DM) phenotype in different species. An experimental herd of purebred Raramuri criollo cattle in Chihuahua, Mexico, has been selectively managed for beef production during the last 15 yr. Recently, two calves where visually identified as DM animals. The aim of this study was to identify changes in the MSTN gene sequence, associated with the two DM individuals and to screen for carriers of the potential polymorphisms within this herd. The DM paternity of the calves was verified by the SeekSire bovine parentage testing of NEOGEN (Lincoln, NE). A 6.6 Kb fragment of the MSTN gene were amplified by PCR and sequenced using Illumina DNA prep kit in a MiniSeq platform. The resulting reads were analyzed using different bioinformatic programs. SNPs were generated in VCF files and filtered by the following criteria: variant confidence normalized by depth of variant samples (QD) < 2.0, mapping quality (MQ) < 40.0, strand bias(FS) > 60.0. The deduced myostatin protein and the three-dimensional model were obtained with bioinformatic tools. Once a novel variant was identified, a real-time PCR protocol was developed to genotype 100 and 97 herdmates, the allelic and genotypic frequencies were estimated. A 9-bp deletion was identified at the same position as the 11-bp deletion (g.821to 831del11) of the Belgian Blue MSTN allele (Figure 1). Although the latter allele has been found in three Spanish cattle breeds ancestrally related to Raramuri criollo, this is the first report of the 9-bp deletion in the MSTN gene. Such deletion results in the loss of three highly conserved amino acids residues (274, 275 and 276) in MSTN, but does not lead to a premature stop codon as in the case of the 11-bp deletion characteristic to DM Belgian Blue. The in silico three-dimensional MSTN conformation obtained for this allele has some structural differences compared with the protein reference model. The allelic frequencies were 0.85 and 0.15 for the MSTN+ and MSTNdel alleles, respectively, whereas the genotypic frequencies were 0.71, 0.01 and 0.28 for MSTN+/MSTN+, MSTNdel/MSTNdel MSTN+/MSTNdel genotypes, respectively. Controlled mattings to generate different genotypes in the research herd would allow to continue studying the effects of this MSTN gene variant on productive performance, forage behavior, husbandry and carcass and meat quality traits known to be affected by the DM phenotype in beef cattle.
PSVII-8 Survival analyses of the productive life in U.S. Katahdin ewes
Authors: Pinto Luis F B , Lewis Ronald M , Rocha Artur O , Nilson Sara M , Murphy Tom W , Wilson Carrie S , Freking Brad A , Burke Joan M , Brito Luiz F
Published: September 2024

Ewe productive life (PL), defined as the number of days between the first and last lambing, is a common indicator of longevity. This study aimed to analyze the PL of 10,276 Katahdin ewes, of which 69.3% were uncensored and 30.7% were right-censored records. Ewes were daughters of 1,188 sires and 6,312 dams, born between 1989 and 2021 in 58 flocks located across the U.S., and the National Sheep Improvement Program provided the data. Ewes with lambing interval and age at first lambing greater than 720 d and 1,095 d, respectively, were excluded. Moreover, flocks that did not report lambing records across at least 7 consecutive years or did not have an average of 20 or more lambing records over the year were also left out of the analyses. Survival functions were analyzed using the Kaplan-Meyer (KM) and Cox models, while the Hazard function was analyzed using the Cox model. For the Cox model, contemporary group (concatenation of flock, year, and season of ewe’s birth) was fitted as a random effect; the ewe’s BR class (combined effect of birth/rearing types: 1/1, 2/1, 2/2, 3/2, 3/3, with digit-3 including counts ≥ 3), ewe’s age class at first lambing (≤ 378d; 379 to 700d; and > 700 d), and the ewe’s dam’s age class (A: < 713 d; B: 713 to 1,486 d; C: > 1486 d) were fitted as fixed effects. All survival analyses were performed using the Survival R-package. All factors included in the Cox model were highly significant (P < 0.001), except dam age class (P > 0.05). The proportional hazard assumption was checked using a graphical diagnostic based on the scaled Schoenfeld residuals, and there was no failure in the assumption. Moreover, there was no evidence of influential or outlier records in the graphical analysis of the residuals. The Cox survival curve overlapped with the KM survival curve (Figure 1), indicating a good survival prediction with the Cox model. The median PL was 1,036 d (95%CI: 1001 to 1,056 d) with the KM model and 1,056 d (95%CI: 984 to 1,078 d) with the Cox model. The hazard ratio indicated BR levels 2/2 and 3/3 showed less hazards than group 1/1 (Figure 2), and thereby longer PL; no significant difference was observed between 1/1 and the other two levels (2/1 and 2/3). Ewes that first lambed before 378 d had less hazard than those with the first lambing after this age (Figure 2). There was no significant difference between the dam age classes. In conclusion, over 50% of Katahdin sheep have less than 3 yr PL. Moreover, U.S. Katahdin ewes born from larger litters and having the first lambing before 378 d are likelier to have a greater PL.
PSX-9 Comparison of single- and multiple-trait genomic predictions of cattle carcass quality traits in multibreed and purebred populations
Authors: Peters Sunday O , Kizilkaya Kadir , Garrick Dorian , Reecy James
Published: September 2024

Estimation of genetic parameters for carcass traits and their use in the evaluation of carcass quality is of considerable importance in the genetic improvement of beef cattle. The objective of this study was to compare the predictive ability of single- and multi-trait genomic prediction models for the following carcass quality traits: hot carcass weight (HCW); fat thickness (FAT); rib eye area (REA); marbling score (MARB); and peak force (PEAKF) from multibreed and purebred populations. The purebred population included 1,068 purebred Angus animals from Iowa State University whereas the multibreed population consisted of 887 animals sired by 1 of 8 purebreds (209 Angus-, 10 Brahman-, 182 Charolais-, 76 Hereford-, 44 Limousin-, 136 Maine-Anjou-, 96 Shorthorn-, and 134 South Devon- sired offspring) from the Carcass Merit Project funded by the US beef cattle industry to evaluate the genetic prediction of tenderness. After quality control of SNP markers generated with Illumina v1 50K BeadChips, 33,718 SNP markers from were used to obtain heritability and genetic correlation estimates between traits separately in either the multibreed or purebred populations. Genotyped individuals were randomly clustered into 10 groups for cross-fold validation to quantify the correlations between and predicted performance (without the individual’s data) and the realized phenotype of the individual from single- or multi-trait genomic prediction in the multibreed and purebred populations. Heritability estimates of traits from multi-trait analyses ranged from 0.42 to 0.61 in multibreed population and from 0.24 to 0.44 in the purebred population, whereas the single trait values were 0.30 to 0.53 in multibreed, and 0.23 to 0.42 in the purebred population. Estimates were greater in the multibreed population compared with the purebred population (Table 1). Compared with the single-trait analyses, multi-trait analyses resulted in higher heritability estimates for FAT, REA and PEAKF traits in the purebred population and for HCW, REA, MARB and PEAKF traits in multibreed population. Genetic correlations from multi-trait analyses indicated the genetic association between traits. In testing data sets, correlations between observed and predicted phenotypes from single-trait analyses were 4- to 7-fold greater in purebred than in the multibreed population (Table 2). These results may be due to the greater genomic relationship expected in purebred than in the multibreed population. However, the multi-trait analyses resulted in a considerable increase in correlations between observed and predicted values in multibreed population due to genetic correlations between traits.
PSX-6 Genome-wide association study on hippocampal biomarkers of cumulative affective experience in chicken layers
Authors: Neuert Lindsay , Osborne Vern R , Armstrong Elena A , Boswell Timothy , Smulders Tom V , Baes Christine F , Makanjuola Bayode O
Published: September 2024

Recurring stress, which can be termed a negative cumulative affective experience has numerous detrimental phenotypic impacts on poultry welfare. Consequently, this negative experience could lead to reduced productivity. Biomarkers that serve as indicators of cumulative affective experience have been found through the density of highly plastic neurons in the hippocampus. There is limited published research on biomarkers of cumulative affective experience in poultry. Therefore, identifying genomic regions associated with the biomarkers of poultry susceptible or resistant to the negative affective experience could aid in creating more efficient and sustainable farming practices. For this study, H&N and Hy-Line Brown hens (n = 42) housed in a multi-tier free range and enriched cage system, respectively, were available. All hens were genotyped with a proprietary 200K SNP panel and phenotypic data were collected from brain tissue sections stained using an antibody to doublecortin (DCX), which was used to quantify densities of highly plastic neurons in the hippocampus. A genome-wide association study (GWAS) was used to detect genomic regions associated with biomarkers of cumulative affective experience in poultry. The GWAS results found a total of 19 regions from 8 chromosomes with a comparatively high proportion of genetic variance explained, which is associated with the cumulative affective experience. From these regions, 39 different genes were found to be within 100 kb upstream and downstream of the identified regions. These genes were examined for their biological function and role in the cumulative affective experience. The identified genes are associated with cellular processes and genetic information processing. Of the genes, PIKR6, VPS37D, STX1A, BAZ1B, HGH1, MAF, MAPK15, PIT54 were identified as important candidate genes for the cumulative affective experience. Notably, the identified gene, PIK3R6, overlapped with previously reported genes for the stress response in chickens. These identified genes with association to the hippocampal neural density serve as potential candidate genes underlying the cumulative affective experience in poultry. This study shows that genomic regions associated with cumulative affective experience can be detected and help to provide insight into the genetic architecture of the trait.
PSIII-25 Isolation of a deoxynivalenol (DON)-degrading microbial consortia from soil
Authors: Bumunang Emmanuel , Alexander Trevor , Ellert Benjamin , Jin Long
Published: September 2024

Mycotoxins, such as deoxynivalenol (DON) produced by Fusarium, are harmful fungal secondary metabolic products that cause economic losses and health risks to humans and livestock. Measures to control and prevent feed contamination with DON are necessary to ensure the safety of livestock. These include strategies based on preventing fungal contamination of feed or limiting contaminants in feed through mycotoxin adsorption and degradation. Soil is a valuable source of diverse microbial communities, potentially harboring DON-degrading bacteria that can be developed into feed additives to mitigate DON. This study aimed to identify microbial consortia from diverse soil samples, that could degrade DON. Soil from central (Lacombe; LA) and southern (Lethbridge; LE) Alberta were used as microbial inoculant. These soils were suspected to host Fusarium spp. which could produce DON in cereal crops growing upon them. The LE samples were further categorized into soil amended with manure (LE-MA) or non-manure (LE-UF). Prior to the study, soil pH and moisture content were measured. After soil collection, field-moist samples were mixed with DON-contaminated wheat (10% wt/wt; d 0) and each soil type was divided into triplicate pots and placed in a controlled environment for 32 d. On d 0, 7, 14 and 32, subsamples were collected from pots, serially diluted in a limited medium containing DON (10 µg/mL) as the only carbon source, and incubated for 2 wk (30°C). The degradation of DON in bacterial cultures was calculated using ELISA. The LA soil was slightly acidic (pH 6.4) compared with LE-MA (7.3) and LE-UF (pH 7.0), while moisture content was greater in LA (18.4%) than LE-MA (14.7%) and LE-UF (13.5%) soils. DON-degrading activity was only detected in LA soil samples and was greatest after 7 d of incubation (21%). We are currently isolating individual bacteria from LA soil for identification and are characterizing the soil microbiota using 16S rRNA sequencing. Overall, this study showed that soil contained bacteria capable of degrading DON, however variation existed depending on soil source.
PSIV-21 Lipopolysaccharide (LPS) challenge alters the plasma metabolome of beef cattle
Authors: Barker Samantha N , Carroll Jeffery A , Sanchez Nicole C Burdick , Broadway Rand R , Richeson John T , Kerth Christopher , Hernandez Manuel S , Legako Jerrad F
Published: September 2024

The objective of this study was to evaluate the serum metabolome at 3 major time points in cattle subjected to a lipopolysaccharide challenge. Steers (n = 10; 379 kg ± 30.7) were challenged intravenously with LPS [0.25 µg/kg body weight (BW)], and plasma was isolated from blood at -2, 0, 2, 4, 6, 8, 10, 12, 18, 24, 36, and 48 h relative to the LPS challenge at 0 h. Samples were selected for metabolomic analysis at -2, 2, and 8 h of the challenge based on oxidative stress markers present in companion studies. Liquid chromatography-electrospray ionization-high resolution mass spectrometry was used to separate and detect metabolites (50 to 1,400 m/z). Mass spectral features were annotated using MS-DIAL. Total ion count intensities were median normalized, log10 transformed, and analyzed using MetaboAnalyst v.5. Partial least squares-discriminant analysis (PLS-DA), agglomerative clustering (AHC), and an analysis of variance (ANOVA) with a false discovery rate (FDR) adjusted P < 0.05 were conducted. Of the 245 annotated metabolites, 155 differed between time points. Partial Least Squares- Discriminant Analysis (PLS-DA) and variable importance in projection (VIP) plot were used to visualize treatments and identify compounds driving discrimination between groups. Hierarchical clustering using the Ward method was used to determine metabolite differences present following an endotoxin challenge in cattle. Pathway analyses were also conducted via KEGG Bos taurus pathway library. Based on AHC, 2 clusters were generated where -2 h clustered separate from 2h and 8h. A PLS-DA explained most variation within the model across Component 1 (47.5%), with clear separation of metabolites present at -2 h versus those present at 2 and 8 h post challenge. A VIP plot recognized metabolite differences driven by taurocholic acid, LysoPE (18:3; Lysophospholipid), butyric acid, acitretin, and tauromuricholic acid. Pathway analyses further identified arginine biosynthesis, beta-alanine metabolism, arginine and proline metabolism, and histidine metabolism as the metabolic pathways likely driving differences in the data (FDR P < 0.05). These data suggest that metabolites change drastically following an immune response and identify differences which may be further related to or contributing to oxidative stress in vivo. Additional research could aid in the identification of biomarkers significant to recognizing immune dysfunction and oxidative stress.
PSIV-16 The role of veterinary services on nutrition schemes, management, and health practices for sheep and goats in rural Ngaka Modiri Molema District Municipality, North West Province of South Africa
Authors: Mokolopi Baitsholetsi Gloria , Oguttu James W
Published: September 2024

Poverty is a feature of rural households, and as a result rural people usually adopt low-input agriculture to alleviate poverty. Many households in Ngaka Modiri Molema District keep animals, particularly sheep and goats, for a variety of reasons, including as source of income, milk, and meat. However, they lack the management skills that are necessary for their livestock to increase their productivity. Inadequate animal management, including poor feeding and housing standards and poor application of proper animal health procedures are compounded by a lack of agricultural experience and low-input farming methods. In addition, poor animal nutrition, sickness and a high prevalence of parasites, and low animal production output further contribute to low overall productivity. Therefore, support offered by the veterinary services, and the impact these interventions have on sheep and goat farming among rural farmers need to be investigated. The present study will seek to describe the feeding schemes and management practices adopted by sheep and goat owners, as well as the role of veterinary and extension services in the development of such practices. Health care provided to sheep and goat farmers by the veterinary services will also be determined. A survey will be conducted in Ngaka Modiri Molema District Municipality, a rural area in North West Province of South Africa. The study population will consist of all farmers, both female and male, rearing sheep and goats. Animal and farm information level data and general farm management practices will be collected via a questionnaire survey. Using the Statistical Kit for STATA (version 16), data will be examined by computing frequency, percentages, and proportions based on the characteristics of the sample population. This survey will help to provide opportunities for resource-poor farmers in rural areas to develop their flocks.
PSI-12 Comparison of body composition ultrasound versus carcass collection data, Warner-Bratzler shear force and ether extract testing on Beefmaster Steers
Authors: Fuqua Ainslea E , Lawrence Ty E , Lust David G , Perkins Tommy L
Published: September 2024

The objective of this study was to determine if ultrasound estimates of carcass quality traits could predict the final quality factors that influence purchases of consumers. Beefmaster steers (n = 86) representing two different sires were ultrasounded 48 d and 73 d before harvest using an Aloka 500 ultrasound unit, equipped with a 17.2cm probe to collect 12th rib fat thickness (BFU), 12th rib longissimus muscle area (LMAU), intramuscular fat (%FATU) and rump fat (RFU). International Livestock Image Analysis (I.L.I.A) software (Harrison, Arkansas) was used for processing images to determine BFU, LMAU, %FATU and RFU using chute side captured ultrasound images on all steers. An Ultrasound Guidelines Council (UGC) field and lab certified technician captured all ultrasound images. Carcass data collection included 12th rib fat thickness (BFC), 12th rib longissimus muscle area (LMAC) and marbling score (MS). Additionally, Warner Bratzler shear force (WBSF) and ether extraction (EE) estimates were determined on 12 to 13th longissimus muscle samples. All carcass data was collected by the Beef Carcass Research Center (BCRC) at West Texas A&M University. Data were analyzed using SAS version 9.4. Simple descriptive statistics were 1.03 ± 0.26 cm, 88.8 ± 8.61 cm2, 5.02 ± 0.93, 1.27 ± 0.36 for BFU, LMAU, %FATU, and RFU, respectively. Simple descriptive statistics were 1.72 ± 0.41 cm, 90.06 ± 7.24 cm2, 5.06.7 ± 0.69, 6.08 ± 1.92, and 3.34 ± 0.79 kg for BFC, LMAC and MS, EE and WBSF, respectively. Pearson correlation coefficients were 0.71 (P < 0.001) between BFU and BFC, 0.42 (P < 0.0001) between LMAU and LMAC, and 0.35 (P < 0.001) between %FATU and MS. Pearson correlation coefficients were 0.42 (P < 0.001) between EE and %FATU and 0.59 (P < 0.0001) between EE and MS. These results suggest that ultrasound measures of final body composition should be taken closer to the final harvest date to better estimate endpoints of fat thickness, longissimus muscle area and intramuscular fat in harvest ready beef cattle.
PSI-9 An evaluation of cow activity traits during the breeding season to determine the effect on conception method
Authors: Dubowsky Jason P , Katz Amelia R G , Huzzey Julie M , McFarlane Zachary D
Published: September 2024

The objective of this study was to evaluate grazing activity traits and their influence on conception method during the breeding season. In a 1-yr study, crossbred Angus cows (n = 29) were blocked by age and then randomly assigned to be fitted with a Knight global positioning system (GPS) tracking collar. All cows, except first-calf heifers (n = 12), were synchronized for fixed-timed artificial insemination (TAI) utilizing a 7d CO-Synch + CIDR protocol. Bulls and first-calf heifers were turned out on native rangeland with the cowherd 7 d after TAI for a 65-d breeding season. Cattle were managed in an intensive rotational grazing system (15 pasture movements in the first 21 d of the breeding season) with several daily pasture movements. Cows were retrospectively classified into the following groups for comparison: conception to TAI (AI; n = 12), bull-bred (BB; n =17). Total daily distance traveled (km/d), average daily elevation gain (m/d), and percentage of time spent grazing challenging topography (i.e., > 15% slope) were measured during the first 21 d of the breeding season. Data were analyzed using the MIXED procedure in SAS 9.4. The model included the main effects of conception method, pasture, and their interactions. Total daily distance travelled, and elevation gain exhibited a conception method × pasture interaction (P < 0.05). Amongst the 15 pastures, AI cows in pasture F (d 7 of breeding season, 7.69 ha, minimum elevation 36.27 m, maximum elevation 46.94 m) travelled further than BB cows (P < 0.001). Overall, cows that conceived to AI tended to travel further each day compared with BB cows (P = 0.06). Bull-bred cows exhibited a greater daily elevation gain in pasture F when compared with AI cows (P ≤ 0.001). The percentage of time spent on a challenging slope did not differ among cows (P = 0.20). These data indicate that grazing behavior patterns change based on pasture characteristics and timing of conception. Selection for grazing behavior attributes may be an important tool for selection of cows that are more reproductively punctual.
PSI-21 Limited impact of hypothyroidism on porcine fetal growth during mid to late gestation
Authors: Rudy Kaylyn , Smith Alyssa A , Cabot Bea , Pasternak J Alex A
Published: September 2024

In the fetal pig, both circulating thyroid hormone and growth rate are known to increase throughout gestation; however, the functional association between these coincident factors has not been established. Thus, the objective of this project was to investigate this cause-and-effect relationship by evaluating the impact of induced fetal hypothyroidism on fetal growth during mid to late gestation. To induce fetal hypothyroidism, n = 12 pregnant gilts were orally treated with the goitrogen methimazole (MMI) at a dose of 5 mg/kg/d for 21 d, with n = 3 gilts starting treatment on gestation d 34, 45, 55 and 65. An equivalent group n = 12 of gilts were sham treated for the same periods to produce gestationally age-matched euthyroid control litters (CON). Upon completion of the treatment period, gilts were humanely euthanized, and the resulting populations of n = 174 MMI and n = 166 CON fetuses deeply phenotyped. No meconium-stained fetuses were observed at any time point, and only 5 mummified fetuses were observed (3 CON, 2 MMI), indicating treatment has no effect on fetal viability. Fetal body weight (BW) and the weights of individual organs including thyroid, liver, heart, lung, kidney, spleen, and brain were collected. In addition, fetuses were imaged in both left and right lateral recumbency for subsequent morphometric assessment using a custom analysis pipeline in ImageJ. Image analysis yielded parameters including crown-rump length, girth, brow length, depth at the snout/skull junction, depth at the snout/nose junction, and area under the skull curvature (AUC). Left and right measurements for all morphometric parameters were found to be highly correlated (r2 > 0.9) indicating a repeatable measure using this approach. Statistical analysis of all phenotypic differences was carried out using a linear mixed effect model including gestational age and treatment as fixed effects and gilt as a random effect. A significant increase in both absolute and relative thyroid weights indicated the development of goiter and thus, successful induction of hypothyroidism within the MMI litters. In addition, a significant treatment by time interaction was observed, with 0.014 g and 0.21 g increase at d 55 and 66, respectively, indicating reduced compensatory action within the fetal hypothalamic-pituitary-thyroid axis during this earliest period. Liver weight as a percentage of BW decreased from 6.06% to 2.56% between d 55 and 86 in the CON group but was significantly increased at all time points in response to MMI induced hypothyroidism (P < 0.01). A corresponding increase in brain to liver weight ratio over time was suppressed in MMI fetuses (P < 0.05). While all other phenotypic parameters were significantly altered by gestational age, there was no significant impact of fetal hypothyroidism. Collectively, the results indicate that fetal growth during mid to late gestation is not driven by fetal thyroid hormone.
PSI-4 The effects of Total Equinegrain containing Ascophyllum nodosum seaweed extract and chelated minerals on cecal digestibility during the recovery period of recovering, malnourished horses
Authors: Boyd Jamie A , Bardassi Ariane Tabari , Martinez Janette , Martinez Jaqueline , Rosa L Patterson
Published: September 2024

From April to June 2023, we conducted a study to evaluate the effects of Total Equine containing Ascophyllum nodosum seaweed extract and chelated minerals on cecal digestibility in 10 recovering malnourished horses. Horses were used on a preceding 8-wk study and given a 21-d washout period with 24 h turnout and ad libitum access to Bermuda hay between trials. Once the washout was complete horses were randomly assigned to one of three diets: Control (Ctrl), a commercial grain product and Bermuda hay (n = 3); Treatment (Trt), Total Equine and Bermuda hay (n = 4); and Grain only (Grn), Total Equine without Bermuda hay (n = 3) for 8 wk with ad libitum access to water. For Ctrl and Trt diets, hay was offered hay twice a day in port-a-grazer tubs to control waste. Orts were collected 2x/d and hay offered was adjusted daily to maintain a 3 % refusal rate. Horses were weighed weekly with an electronic equine scale and BCS was evaluated at wk 0, 4, and 8. Grain was offered at a rate of 0.005% BW + 227 kg and divided into 2 equal feedings for Ctrl and Trt diets, while Grn diet horses were offered up to 9.07 kg of grain per day divided into 3 feedings. Grain offered was adjusted weekly based on BW. For physical reconditioning, horses were exercised 5 d/wk with a Priefert hot walker with an increase in duration and intensity from wk 1-8. Samples were collected of grain, hay, and orts for DM, NDF, ADF, EE, CP, and ash analysis. Cecal digestibility (dNDF and dADF) of Bermuda was measured using the Ankom Daisy system at wk 4 8 for 48 and 72 h. Jars were inoculated with a fresh composite fecal sample. Fecal samples were equally composited by diet. Data were analyzed using Proc Mixed procedures in SAS. No effect was observed on dNDF by diet (P = 0.21), yet diet*week (P = 0.0005) and diet* hour (P = 0.04) differed. dADF was improved by diet*week (P ≤ 0.0004) for diets containing Total Equine grain versus the Ctrl diet. Results indicate dNDF and dADF improved for wk 8 versus wk 4, which may indicate recovery of microbial efficiency as horses recovered. The improvement in dADF for Trt and Grn diets versus Ctrl is noteworthy, particularly the increase in dADF (Grn) because of the lack of hay in this diet. Improvement in fiber digestibility may help explain the improved body weight gain of horses on Trt and Grn diets in comparison to the Ctrl. Further research is needed to fully evaluate the impact of Total Equine on cecal digestibility especially in recovering, malnourished horses.
PSI-18 Intra-articular triamcinolone acetonide administration does not affect microbial culture or synovial fluid volume in young, exercising Quarter Horses
Authors: Pavel Lauren R , Leatherwood Jessica L , Gualandri Cecilia R , Paris Brittany L , Arnold Carolyn E , Glass Kati G , Carter Maggie M , George James M , Linne Paige K , Martinez Rafael E , Moore Grace E , Spooner Holly , Bradbery Amanda N
Published: September 2024

Intra-articular corticosteroids (IAC) are administered to horses experiencing joint inflammation, at times with a concurrent articular antibiotic for prophylaxis. However, information regarding the biologic effects of IAC and potential for microbial contamination in IAC-administered joints is limited in young, exercising horses. The objective of this study was to evaluate the impact of IAC on traditional microbial culture, synovial fluid (SF) volume, and the presence of IAC; hypothesizing negative microbial culture, no change of SF volume, and detection of IAC in SF post-administration. To test this, 2-yr-old Quarter Horses {n = 24; body weight (BW) = 409 ± 6 kg; 825 ± 21 d of age; 12 fillies, 12 geldings) were stratified by BW, age, and sex, and randomly assigned to 1 of 3 treatment groups for a 56-d trial. Horses were housed individually in stalls with runs and fed concentrate offered at 0.75% BW/d split evenly every 12 h with ad libitum Coastal bermudagrass hay and water. Every 21 d, BW and body condition score (BCS) were recorded, and concentrate was adjusted accordingly. Horses were exercised 5 d/wk, up to 45 min/d in a progressive workload using a free-stall exerciser. Blood was collected post-exercise during wk 1, 4, and 7 via jugular venipuncture and lactate (BL) was measured to monitor increasing workload. Intra-articular treatments consisted of 0 mg (CON; n = 8), 6 mg (CORT6; n = 8), or 12 mg (CORT12; n = 8) of triamcinolone acetonide (TA). On d 0, treatments were administered in one randomly selected radiocarpal joint per horse. Following aseptic preparation, SF from both radiocarpal joints was collected before administration (pre), and on d 7, 14, 28, and 56. Volume of SF was recorded, and standard microbial culture and detection of TA were performed by a commercial laboratory. Data were analyzed using PROC MIXED (BW, BCS, BL, SF volume) and PROC GLM (TA) of SAS. For SF volume, data from the contralateral radiocarpal joint were used as a covariate. Horses increased BW and BCS over time (P ≤ 0.01) across treatments. Post-exercise BL increased from wk 1 to 4 and remained increased through wk 7 (P < 0.01). Microbial culture for all horses and time points were negative. Concentration of TA was not evaluated on d 7 due to limited SF volume, but TA was detected on d 14 and concentration did not differ between CORT6 and CORT12 (P = 0.13). Recorded SF volume did not change from d 0 (pre) to 7 but increased to d 56, regardless of treatment (P < 0.01). These results indicate that, based on standard culture, TA administration did not result in positive microbial culture, or decrease SF volume in young horses undergoing regular exercise, however, TA was detectable to d 14.
PSIII-7 Effects of Saccharomyces cerevisiae fermentation product on total tract digestibility, ruminal fermentation, and plasma metabolome of beef steers fed a finishing diet
Authors: Dhungana Anjan , Odunfa Oluwaseun , Woods Daniel , Osterman Anthony , Ogunade Ibukun M , Yoon Ilkyu , Jiang Yun
Published: September 2024

Saccharomyces cerevisiae fermentation product (SCFP) has been widely studied; however, its mode of action on high-concentrate diets has not been fully elucidated. This study evaluated the impact of SCFP on total tract digestibility, fecal excretions of N, P, Zn, and Cu, rumen fermentation, and plasma metabolome of finishing beef steers. Ruminally cannulated Holstein steers [n = 8; body weight (BW) = 580 ± 29.2 kg] were enrolled in a crossover design study with 25-d treatment periods and a 24-d washout period. Steers were fed ad libitum a finishing diet consisting of 20% corn silage and 80% concentrate (on DM basis). Steers were blocked based on initial BW and randomly assigned to two treatments in period 1 and switched to the other treatment in period 2. The treatments were CON (Control, basal diet only) and SCFP (basal diet top-dressed with 12 gּ steer-1ּ ּ d-1 SCFP, NaturSafe, Diamond V, Cedar Rapids, IA). Feed and fecal samples were collected during d 22 to 24 for determination of digestibility. Blood was collected before morning feeding on d 25. Plasma samples were analyzed for metabolome with liquid chromatography-mass spectrometry (LC-MS). Rumen fluid was collected via the rumen cannula at 0, 4, 8, and 12 h post-morning feeding on d 25 and analyzed for pH, volatile fatty acids (VFA), and NH3-N. Performance and ruminal fermentation characteristics data were analyzed using the GLIMMIX procedure of SAS 9.4. Metabolomic data analysis was conducted with Metaboanalyst 6.0. Supplementing steers with SCFP reduced DMI (10.6 vs. 11.4 kg/d, P = 0.05) without affecting (P > 0.05) average daily gain, feed efficiency, and digestibility of organic matter, crude protein, and neutral detergent fiber. Treatment did not affect (P > 0.10) fecal excretions of N, P, Cu, and Zn. Feeding SCFP increased ruminal pH (6.29 vs. 6.01, P = 0.01), numerically reduced concentrations of NH3-N (5.01 vs 6.25 mM, P = 0.16), and total VFA (96.8 vs. 102.5 mM, P = 0.15). SCFP also reduced the ruminal molar proportion of butyrate (11.2 vs. 12.8 molar %, P = 0.01) and tended to increase those of isobutyrate (1.03 vs. 0.90, molar %, P = 0.06) and isovalerate (2.62 vs. 2.29, molar %, P = 0.10). Supplementation of SCFP enriched (P ≤ 0.05) purine metabolism, amino sugar and nucleotide sugar metabolism, and lysine degradation pathways in the plasma. Additionally, tryptophan metabolism and pyrimidine metabolism pathways tended to be enriched (0.05 < P ≤ 0.10) by SCFP. Our findings indicate that feeding SCFP improved the ruminal pH of finishing cattle, which may be beneficial for preventing subacute ruminal acidosis in feedlot cattle. Additionally, SCFP enriched several important plasma nitrogen metabolism pathways, potentially associated with microbial nitrogen metabolism in the rumen, warranting further research.
PSIII-12 Dynamics of neonatal dairy calf behaviors and their association with early gut microbiota
Authors: Hawkins Jalyn G , Carpenter Shelby , Brett James , Hsu Chuan-yu , McGee Marcus , Smith Trent , Stone Amanda , Fan Peixin
Published: September 2024

The behavior of dairy cattle can be both an indicator and a determinant of their productivity and health. Additionally, animal behavior is also associated with their gastrointestinal microbiota through the bi-directional pathways of the gut-brain axis, influencing nutrient utilization and gut health. Few studies have looked at the dynamics of neonatal calf behaviors and their associations with early microbiota development. Therefore, the objective of this study is to observe feeding behaviors and activity of neonatal dairy calves and investigate its associations with the diversity and composition of early-stage gut microbiota. We used Holstein-Angus crossed calves (n = 25) raised in individual outdoor hutches and bucket-fed milk replacer twice daily. The number of milk exposures until calves were successfully bucket trained was recorded, along with milk consumption times during the AM feedings on d 7, 11, and 14. We also monitored the activity of the calves using HOBO Pendant G Data Logger accelerometers secured on the right hind leg of each calf to monitor standing and lying behavior from d 3 to d 13. Fecal samples were collected from the recto-anal junction of the calves at d 7 and 14 after birth and gut microbiota were analyzed using full-length 16S rRNA gene amplicon sequencing on an Oxford Nanopore sequencer. The Generalized Linear Model (GLM) was applied to evaluate effects of gender and birth weight on behavior and gut microbiota using RStudio 4.2.1. The Linear discriminant analysis Effect Size (LEfSe) was used to determine the unique bacterial species for each behavioral group. The results revealed that there was no influence of sex or birth weight on bucket training or consumption time; however, male calves exhibited significantly increased total standing time compared with female calves. We found no significant difference in microbiota between fast-learning calves (one milk exposure; n = 3) and slow-learning calves (5 or more exposures; n = 3). We observed greater alpha diversity of slow drinking calves (top 25%; n = 6) compared with fast drinking calves (top 25%; n = 6) on d 7 (Chao1; P = 0.03). The LEfSe analysis identified Akkermansia muciniphilia to be more abundant in fast drinking calves, and Megasphaera elsdenii to be more abundant in slow drinking calves. Additionally, a trend of differing microbiota composition was observed between the most active and least active calves (n = 4 per group) on d 14 (Bray-Curtis; P = 0.1), and many Prevotella species were more abundant in the most active calves. In conclusion, this study sheds light on the gut-brain axis of neonatal dairy calves at the species-level and provides further insights into cognitive, consumptive, and active behaviors.