bluuebunny/crossref_metadata_2025 huggingface dataset:
286 The influence of age and winter environment on Rumax Bovibox and Bovibox HM supplement intake behavior of winter grazing beef cattle on mixed-grass rangelands
Authors: Wyffels Samuel , Parsons Cory T , Dafoe Julia M , Boss Darrin L , McClain Tyrell , Carter Boone , DelCurto Timothy
Published: November 2020

This study evaluated the influence of cow age and temperature adjusted for windchill (Twindchill) on supplement intake behavior of cattle winter grazing northern mixed-grass prairie rangelands. A commercial herd of 291 (yr-1) and 316 (yr-2) bred cows were winter grazed on a 329-ha rangeland pasture for 2 years. Cows were assigned to one of six age classifications and were provided free-choice access to Rumax Bovibox HM (2018–2019) and Rumax Bovibox (2019–2020) protein blocks. The target daily intake range was 0.45–0.91 kg∙cow-1∙d-1. Supplement was provided in a SmartFeedPro self-feeder system to measure individual animal supplement intake and behavior. Average daily supplement intake (expressed as kg∙cow-1∙d-1) and variation in supplement intake displayed Twindchill × cow age × yr interactions (P ≤ 0.05). There was no effect of age on daily supplement intake at below average and above average Twindchill in yr 1 (P ≥ 0.07). Age displayed a quadratic effect on daily supplement intake at average Twindchill in yr-1 (P < 0.01) but was limited to 3- and 4-yr-old cattle consuming more supplement per day than yearlings (P ≤ 0.02). During yr-2, cow age had a quadratic effect on supplement intake for all Twindchill conditions (P < 0.01) where 3-yr-old cattle consumed more supplement per day than yearlings, 5–7- and ≥ 8-yr-olds (P ≤ 0.01). Cow age exhibited quadratic effects on variation in supplement intake across all Twindchill conditions during both years (P < 0.01). However, the quadratic effects of age in yr-1 were limited to yearlings having higher variation in supplement intake than all other ages (P < 0.01). In summary, both cow age and the winter environmental conditions interacted to influence animal supplement intake behavior and, as a result, nutrient delivery efficacy in winter grazing beef cattle.
289 Effects of dietary Zn on ewe milk minerals and somatic cell count
Authors: Page Chad M , Murphy Tom , Taylor Bret , Julian Alexis , Whaley Jaelyn , Woodruff Kelly , Hummel Gwendolynn , DeMarco Claudia , Laverell Dylan , Cunningham Hannah , Rule Daniel , Stewart Whit C
Published: November 2020

The objectives of the current study were to evaluate the effects of dietary Zn fed at approximately 3 times NRC recommendations on milk Zn concentrations and mammary health. Within Rambouillet (WF) and Hampshire (BF) breeds, ewes were ranked by BW and randomly assigned down the rank into 2 treatment groups: Control (n = 45, 37 mg Zn/kg DM) and Zn treatment (n = 44, 113 mg Zn/kg DM). Treatments were delivered via a ZnSO4-fortified alfalfa pellet fed at a rate of 0.45 kg/d DM from a RFID-activated automated feeder from approximately 6 wk before to 4 wk after lambing. Ewe milk was collected twice weekly, and analyzed for mineral content (d 0, 10, and 30 of lactation) and somatic cell count (SCC; d 3–5, 6–9, 10–12, 13–16, 17–19, 20–23, 24–26, 27–29, or 30–32). Single-bearing ewes had greater Ca, Mg, and P (P ≤ 0.04) than multiple-bearing ewes. Day of lactation influenced milk Mg, P, and Zn (P < 0.01), and values generally decreased as lactation progressed. Milk Zn was 1.7-fold greater (P < 0.01) for Zn treatment than Control ewes. Milk Ca, Mg, and P were greater for Control than Zn treatment (P ≤ 0.02) ewes. A breed × litter size effect was detected for LogSCC (P = 0.02). Single-bearing WF ewes had lower LogSCC than multiple-bearing WF ewes (5.36 ± 0.09 vs 5.74 ± 0.07; P < 0.01) but litter size did not affect BF ewe LogSCC (5.80 ± 0.08 vs 5.79 ± 0.09; P = 0.92). Day of lactation impacted ewe SCC (P < 0.01), with peak SCC between d 6 and 9, which began to decline as lactation progressed. In conclusion, dietary Zn above NRC recommendations increased milk Zn.
PSV-3 A systems design for sensor-based parturition and calf status detection in rangeland environments
Authors: Chang Anita Z , Trotter Mark G
Published: November 2020

Livestock production in rangeland environments is often fraught with numerous challenges that can limit regular human-animal interaction. As such, cattle in these environments can remain unmonitored for days or months at a time. The integration of on-animal sensing systems in these environments could provide a means for producers to remotely monitor their animals without incurring the significant labour costs associated with manually checking on their livestock. These devices could be used to monitor critical times in a cow’s life, such as calving. Parturition represents a high-risk period in both a cow and calf’s life, where the risk of disease or death is greatly increased. Additional monitoring in this period is beneficial, such that any complications can be promptly detected and managed. On-animal sensing systems could be used to identify when or if calving has successfully occurred and to infer the status of the calf in the first few months of life. For a precise and well-integrated system to be developed, there needs to be a greater understanding of the data required at each stage. This study will provide a conceptual overview and systems design outlining how an on-animal sensor system could be used to detect calving and calf status and provide updates to the producer in the event of complications. This research is funded by Central Queensland University, Meat and Livestock Australia, and Telstra.
PSIII-15 Genetic variability of Russian domestic reindeer populations (Rangifer Tarandus) by microsatellites
Authors: Kharzinova Veronika R , Dotsev Arsen V , Solovieva Anastasiya D , Fedorov Valeriy I , Shimit Larisa D , Romanenko Tatiana M , Senchik Alexander V , Sergeeva Olga K , Goncharov Vasily V , Layshev Kasim A , Yuzhakov Alexander A , Brem Gottfried , Zinovieva Natalia A
Published: November 2020

Domestic reindeer are bred across the Russian tundra from the Kola Peninsula to Chukotka and in the mountain-taiga zone. To understand the genetic diversity and population structure of domestic reindeer, 528 individuals were analyzed using 14 microsatellites. The sample included the Nenets breed of the Komi Republic (NEN_K, n = 42), Nenets (NEN_N, n = 148), Yamalo-Nenets (NEN_Y, n = 46), Archangelsk (NEN_A, n = 47), Murmansk (NEN_M, n = 43), Taymyr (NEN_T, n = 52) regions; the Even (EVN, n = 33), the Evenk (EVK, n = 31), the Chukotka (CHUY, n = 33) breeds of Yakutia; the Chukotka breed (CHU, n = 40) of Chukotka Region; the Tuvinian (TUV, n = 32) and Mongolian (MGL, n = 21) populations of the Tuva Republic and Mongolia. Calculations were done in R package “diveRsity,” software SplitsTree 4.14.6., Structure 2.3.4. Possibly due to permanent exchanges with animals among farms of the Nenets region and thus introduction of “foreign” alleles into the herds, a higher level of genetic diversity was found in NEN_N (HE=0.699; AR =6.086). All groups had a significant homozygote excess with the maximal value of FIS in geographically isolated populations MGL (0.326) and TUV (0.229). Neighbor-Net tree showed formation of three main clusters according to breed origin and breeding region: (1) the Nenets reindeer from different regions, (2) three breeds of Yakutia and (3) TUV and MGL populations. CHU branched individually with a distance from others. At K=11 of STRUCTURE, we observed a clear clustering of CHU, MGL, TUV, NEN_T. A middle level of admixture was detected in NEN_A, NEN_Y, NEN_M and NEN_N with NEN_K and CHUY with EVN/EVK, which formed one cluster. Here, we obtained more detailed information on genetic variability of Russian domestic reindeer, which would assist to fill current gaps in knowledge about this essential species for many indigenous peoples of the Far North. The study was funded by the RSF within Project no. 16-16-10068-P.
PSXII-26 Maternal energy restriction in early gestation affects MYOG network topology of bovine skeletal muscle
Authors: da Silva Diniz Wellison Jarles , Crouse Matthew S , Cushman Robert A , Caton Joel , Dahlen Carl R , Reynolds Lawrence P , Ward Alison K
Published: November 2020

Maternal nutrition has long-term consequences in muscle development through transcriptomic changes. Although gene expression differences were reported between dietary treatments, the relationship between genes and its role in the regulation of specific pathways is still limited. Herein, we performed a gene co-expression network (GCN) analysis to determine the relationship between maternal nutrition, gene expression, and the pathways that control skeletal muscle development. Gene expression was measured with RNA-Seq in 14 fetuses collected on day 50 of gestation from dams fed a diet initiated at breeding to either achieve 60% (RES, n = 7) or 100% (CON, n = 7) of NRC energy requirements. After data quality control, mapping, and normalization, we constructed a GCN for 14,205 genes by using the PCIT approach. The networks were built individually for CON and RES groups resulting in approximately 3 and 4 million significantly correlated pairs (P < 0.05), respectively. To reduce the network complexity, we selected those correlated genes (r > |0.95|) that were previously reported as differentially expressed for these animals. Although we identified a greater number of hub genes in the CON group (35 vs. 22), the connectivity degree was significantly higher in RES. The over-representation analysis pointed out different pathways between the exclusively connected genes from each group. Signaling pathways such as FoxO and AMPK underlay the CON group (n = 1,393 genes), whereas fatty acid metabolism, mTOR, and insulin were over-represented in the RES group (n = 2,453 genes). MYOG, a transcription factor required for myogenesis, was identified among the hub genes in both groups; however, it was 70.5% more connected and 33% more expressed in the RES group (P < 0.001). In summary, energy restriction likely modulates gene expression, specific functions, and consequently, muscle metabolism by affecting gene-specific sub-networks. USDA is an equal opportunity provider and employer.
PSXII-30 SNPs IN THE GROWTH HORMONE GENE OF WILD AND DOMESTIC REINDEER (Rangifer tarandus) IN RUSSIA
Authors: Krutikova Anna , Dementeva Natalia
Published: November 2020

In the northern part of Russia, there are wild and domestic reindeer. There are four breeds of domestic reindeer in Russia: Nenets, Evenki, Even and Chukchi. The breeds are adapted to various climatic zones of habitat (tundra or taiga). Breeds vary in growth and live weight, as well as in areas of application. The aim was to study the polymorphism of the gene for growth hormone in the reindeer. The DNA was extracted by the phenolic method using the standard method using proteinase K from blood and tissues. Specially designed primers were used to amplify the site of growth hormone gene. As a result of amplification, a 422 bp fragment was obtained covering the region of the somatotropin gene containing 2 and 3 exons. The resulting amplification was sequenced on an Applied Biosystems 3500 Genetic Analyzer using the BigDye® Terminator v3.1 Sequencing Standard Kit according to the protocol. Four single-nucleotide polymorphisms of C12T, C72T, A122G, A235G were detected in the investigated region of the growth hormone gene (somatotropin). The positions of the found SNPs were determined from a similar section of the gene in a red deer (Cervus elaphus), the genome of which was completely sequenced. Two SNPs are in the intron, two are in the exon. The frequencies of genotypes and alleles were calculated in the six studied populations of domestic and wild reindeer. The results obtained in the study make it possible to draw conclusions about the genetic difference between the populations of wild and domestic reindeer of Russia, and between the domestic reindeer of different breeds. Theme АААА-А-18-118021590138-1.
PSXII-21 Genome-wide search for genomic regions under putative selection in two Russian native cattle breeds using high-density SNP Bead Chip
Authors: Dotsev Arsen V , Zinovieva Natalia A , Deniskova Tatiana Evgenievna , Abdelmanova Alexandra , Sölkner Johann , Reyer Henry , Wimmers Klaus , Brem Gottfried
Published: November 2020

National livestock genetic resources are the valuable source of genetic variability, which are necessary to ensure the sustainability of the local animal production systems. The aim of our work was to characterize the genomic architecture and to detect signatures of selection in two oldest Russian native cattle breeds, using high-density DNA arrays. Fifty-six animals of Yaroslavl (n = 31) and Kholmogor (n = 25) were selected for the study. The Illumina Bovine HD BeadChip (777,962 SNPs) was used for genotyping. High-density SNP genotypes for Holsteins (n = 25) were used as the reference. Three methods (Fst, hapFLK, and ROH) were implemented to detect the genomic regions to be under putative selection. The results of the PCA-plot, Neighbor-Net analysis and Admixture clustering showed clear genetic differences between Yaroslavl and Kholmogor breeds as well as between them and Holsteins. Comparison of the results produced by different methods showed presence of twelve regions in genome of Yaroslavl breed and nine regions in genome of Kholmogor breeds, which were identified at least by two methods. We have confirmed nine regions under putative selection in genome of Yaroslavl cattle and six regions in genome of Kholmogor cattle, which were described previously based on medium-density SNP genotypes, herewith the flanking positions of the most of these regions were expanded. Additionally, we detected three new putative genomic regions affected by selection in each studied breed, which were localized on chromosomes 4, 15 and 17 in Yaroslavl breed and on chromosomes 12, 15 and 18 in Kholmogor breed. The functional annotation of genes localized within identified regions was carried out. Our research results can be useful for genetic improvement of the studied cattle breeds and for developing the programs for their conservation. The study was supported by RSF within project No. 19-76-20012.
PSXII-36 Use of FSH or hCG to enhance follicular growth and pregnancy per artificial insemination during a split-AI program in crossbreed beef heifers
Authors: Castaneda Daniella C Heredia , Ojeda-Rojas Oscar Alejandro , White Darrel , Londono Maria C , Lasso Sergio D , Enriquez Guido E , Ugarte Maria B , Macay Gabriela , Venturini Mauro , Gonella-Diaza Angela M
Published: November 2020

The objective of the study was to compare follicle growth and pregnancy per artificial insemination (P/AI) in crossbreed heifers receiving either a low dose of hCG (150 IU) or a low dose of FSH (20 mg) vs. a control group during the final stage of a split-AI protocol. A total of 387 heifers were enrolled in the trial and were randomly assigned in three treatments (Control n = 134, FSH n = 125, and hCG n =128) within reproductive tract score (RTS; 1 to 5 scale), body condition score (BCS; 1 to 9 scale) and pubertal status. All groups were synchronized with a 7-day CO-Synch + CIDR protocol, at CIDR removal the two treatments were injected, an Estrotect patch was placed, and the diameter of the dominant follicle was assessed through transrectal ultrasonography, at day 9 heifers that presented estrus (> 50% of the Estrotect patch rubbed off) were AI, and those that did not were TAI at day 10. An ultrasound was carried out along with the AI to measure the diameter of the preovulatory follicle and 30 days after for pregnancy check. The data was analyzed using the GLIMMIX procedure (SAS). The diameter of the preovulatory follicle was different among treatments (Control: 11.48 ± 0.21; FSH: 11.48 ± 0.25; hCG; 10.73 ± 0.28; P = 0.01). However, the rate of follicular growth (Control: 4.96 ± 0.37; FSH: 4.59 ± 0.39; hCG: 5.12 ± 0.38; P = 0.64) and P/AI (control: 41.35%; FSH: 35.77%; and hCG: 34.38%; P = 0.47) were not different among groups. There was a significant difference (P < .0001) in P/AI when comparing animals that presented estrous (48.99%) or not (29.27%). In conclusion, the use of low dosed of hCG or FSH at the time of device removal did not increase the proportion of pregnant heifers.
PSXII-29 Partitioning of Inbreeding Depression using Pedigree and Genomic Approaches
Authors: Sumreddee Pattarapol , Toghiani Sajjad , Hay Elhamidi , Aggrey Samuel E , Rekaya Romdhane
Published: November 2020

Understanding the accumulation of autozygosity over time in a genome could enhance the assessment of the effect of inbreeding and the mitigation of its harmful impact. To date, runs of homozygosity (ROH) have been commonly used to study inbreeding’s impact in livestock species, as an alternative to the pedigree-based approach. Although inbreeding caused by the mating of animals related through a recent common ancestor is reasonably expected to have more pronounced effects on traits, estimating these effects requires a clear definition of recent (new) and ancient (old) inbreeding. Several methods have been proposed to classify inbreeding using pedigree and genomic information. Unfortunately, these methods are largely based on heuristic criteria (e.g., number of generations from common ancestor and length of ROH segments). To mitigate these deficiencies, we developed a method to classify inbreeding into recent and ancient classes based on a grid search driven by the hypothesis that new inbreeding tends to have a more pronounced effect than old inbreeding. The proposed method was tested using data from Line-1 Hereford cattle population characterized by a deep complete pedigree. Genomic data consisted of 50K SNP genotypes. Effect of recent and ancient inbreeding was assessed on four growth traits (birth, weaning and yearling weights and average daily gain). Thresholds to classify inbreeding into recent and ancient classes varied across traits and sources of information. Using pedigree information, increased inbreeding in the last 10 to 11 generations was considered as recent. When genomic information was using, thresholds ranged between 4 to 7 indicating the ability of ROH segments to better characterize the harmful impact of inbreeding in shorter periods of time. Using several model comparison criteria (adjusted R-squared, AIC, and BIC), the proposed method was better than existing approaches. Furthermore, the method provided a more objective quantitative approach for the classification of inbreeding.
PSVIII-2 Antibody yield for polyclonal egg yolk antibody (IgY) production in laying hens
Authors: Nolden Cherrie , Grisham Abbey , Schaefer Dan , Akins Matt , Cook Mark
Published: November 2020

Antibody production in egg yolks of immunized laying hens is an alternative to conventional mammalian production. Antibody yield peak and duration have not been described for immunoglobulin Y technology using Freund’s incomplete adjuvant (FIA) and C-phosphate-guanosine oligodeoxynucleotides (CpG-ODN) without the inclusion of Freund’s complete adjuvant for enhancing the immune response to an interleukin-10 (IL-10) peptide. This study sought to describe the antibody titer production for an 8 amino acid sequence from the surface of the bovine IL-10 protein (VMPQAENG) as the antigen emulsified with CpG-ODN and FIA in phosphate buffered saline (PBS). 60 hens were assigned to receive the complete vaccine (Peptide), 20 received the vaccine without the IL-10 peptide (Control), and 8 received a PBS injection (Blank). Hens were immunized with 0.25 mL in 4 locations, each breast and each thigh on days 1, 15 and 29. The complete vaccine delivered 0.6 mg IL-10 peptide, 8 µg CpG-ODN, and 0.33 mL FIA per hen on each vaccination day. Eggs were collected regularly until 175 days after the first immunization and the anti IL-10 peptide activities of the yolk were determined by ELISA. Egg titers by treatment were analyzed with a repeated measures ANOVA in SAS. The supplementation of FIA with CpG-ODN produced high titers, of over 100 µg of antibody per mL of yolk (µg Ab/mL yolk), around day 33 through day 76, with a slow decline through day 175 when average titers remained above 40 µg Ab/mL yolk. Peptide egg titers were significantly higher than Blank or Control titers from day 31 though day 175 (P < 0.0001). Titers recovered from Marcq et al. (2015) with similar methods were 1.5 to 7 times lower than these results over the same number of days.
PSI-8 Effect of breed on the abundance and expression of Shiga toxin in Escherichia coli from the recto-anal junction of feedlot beef cattle
Authors: Pan Zhe , Chen Yanhong , Gaenzle Michael , McAllister Tim A , Guan Leluo L
Published: November 2020

Shiga toxin (Stx) is the main virulence factor of Shiga toxin-producing E. coli (STEC), and ruminants including cattle are the main reservoir of STEC. This study aimed to assess whether cattle breed affects the abundance and expression of Stx and to determine whether the expression of host immune genes can serve as markers of STEC colonization. In total, 143 rectal tissue and content samples were collected from feedlot beef steers in 2014 (n = 71) and 2015 (n = 72) composed of three breeds (Angus, Charolais and Kinsella Composite) with differing feed efficiency. The abundance and expression of Stx1 and Stx2 by STEC associated with rectal tissue was quantified by qPCR and reverse-transcription-qPCR, respectively. Four immune genes (MS4A1, CCL21, CD19, and LTB), previously reported to be down-regulated in super-shedder cattle (i.e., > 104 cfu g-1) were selected and their expression was evaluated using qPCR. The abundance of stx1 and stx2 differed (P < 0.001) among breeds in rectal content samples collected in 2014, while no such difference was detected for 2015 samples. Correlation analysis showed that the expression of stx2 was negatively correlated with MS4A1 (R = -0.56, P = 0.05) and positively associated with LTB (R = 0.60, P = 0.05). The random forest model revealed that the expression of selected immune genes could be used as indicators of Stx2 expression and potential STEC colonization with prediction accuracy of MS4A1 >LTB >CCL21 >CD19. Our results indicate that the abundance and expression of Stx could be affected by cattle breed and the year of sampling, suggesting that host genetics and environment influence STEC colonization. The relationship between the expression of host genes associated with immunity and Stx by STEC expression suggests a role of host in STEC colonization, but further validation is needed to confirm the predictiveness of identified markers.
PSI-1 A systematic review and meta-analysis of GWAS and gene expression results of Holstein cattle under negative energy balance and ketosis
Authors: Soares Riani Ananda Nunes , Vargas Giovana , Muniz Malane M , Soares Maria Amelia Menck , Canovas Angela , Schenkel Flavio , Squires Jim
Published: November 2020

Development of ketosis in high-producing dairy cows contributes to animal health issues and highlights the need for better understanding the genetic basis of metabolic diseases. Thus, the aim of this study was to evaluate the pattern of differential gene expression in liver of cows under negative energy balance (NEB), subclinical, and clinical ketosis through a systematic review and meta-analysis of published gene expression and genome-wide association studies (GWAS) results. After screening of the 118 articles found in the systematic review, 20 articles were included in the analysis. For this, 430 significant SNPs identified by GWAS were investigated to see if they were located within genes reported in gene expression studies. A permutation approach was used to identify the biological pathways associated with the metabolic conditions studied. A gene network was created using the differentially expressed genes harboring significant SNPs and a QTL enrichment analysis was performed to identify potential positional candidate loci. This study revealed 14 genes that are differentially expressed in the liver of cows in different metabolic conditions, which harbor 24 significant polymorphisms in reported GWAS. Three significant metabolic pathways were associated with NEB, subclinical and clinical ketosis. In addition, two important genes, PPARA and ACACA, were identified as differentially expressed in the three metabolic conditions. Gene network analysis revealed co-expression interactions among 34 genes associated with functions involving fatty acid transport and metabolism. The genes FN1 and PTK2 were enriched for QTL previously associated with the trait “ketosis” on chromosome 2 and with the trait “milk iron content” on chromosome 14, respectively. These findings improve the understanding of negative energy balance and ketosis in dairy cows, which could enhance selection for cows less susceptible to ketosis and help with the development of potential biomarkers for early diagnosis and prevention of ketosis.
PSI-16 Investigation of Jute to Stimulate Sow Nesting Behavior in Farrowing Crates
Authors: Markland Mary L , Gaskill Brianna N , Johnson Jay S , Lay Donald C
Published: November 2020

Domesticated sows are highly motivated to perform nesting behavior prior to farrowing. However, due to the potential for clogging slurry systems, large amounts of nesting material are not practical to use in most production systems. Therefore, the study objective was to assess an alternative nesting material provided prior to farrowing on sow welfare and reproductive outcomes. We hypothesized that the provision of jute nesting material would decrease sow stress and improve reproductive outcomes. Twenty-one sows were randomly assigned to 1 of 2 treatments: farrowing crate with jute nesting material (n = 11; 40.64 x 21.59 cm) or farrowing crate without nesting material (n=10). Three overlapping jute pieces were attached to the front of the crate to prevent substrate from falling through the slatted floors and disrupting the slurry system. Sows had access to the jute from the time they were moved into the crates (112.4 ± 0.5 d of gestation) until the end of farrowing. Saliva samples were collected, as a non-invasive way to measure cortisol and immunoglobulin A (IgA) to assess stress, on d -1, 0, 1, and 2 relative to farrowing, and a final sample was collected at weaning. Video was continuously coded for observations of jute-oriented interactions. Data were analyzed as GLM using JMP. In the 12 h prior to farrowing, sows spent an average of 30.02 ± 33.12 min interacting with the jute. Although the sows appear to interact with the material, farrowing duration, number of stillborns, IgA, and cortisol did not differ between treatments (P > 0.05). In summary, the treatment was likely not robust enough to satiate the sows’ nest-building needs. Therefore, alternative nesting materials that provide a better outlet for sow behavior, while avoiding negative effects on the slurry system, or ways to present that material should be evaluated to improve sow welfare.
PSI-25 The effect of growth rate on the uterine environment in beef heifers
Authors: Chaney Elizabeth M , Harrison Taylor D , Brandt Kiernan J , Schneider Liesel G , Payton Rebecca R , McLean Kyle J
Published: November 2020

Replacement heifers provide the foundation of breeding herds by incorporating new and improving genetics. Growth rate (GR) manipulation during heifer development may alter the uterine environment via immune response impacting reproductive function. Angus-crossbred heifers (n = 48) were blocked into 4 weight classes and randomly assigned to one of three treatments: 1) control (CON) fed to gain 0.68 kg/day for 120 d, 2) fast to slow (F/S) fed to achieve 1.25 kg/day for 57 d, then 0.11 kg/day for 63 d, and 3) slow to fast (S/F) fed to achieve 0.11 kg/day for 57 d, then 1.25 kg/day for 63 d. Heifers were supplemented (75% dry distillers grain and 25% corn) four times weekly to achieve desired GR and offered ad libitum forage and water. Blood, BW and BCS were taken every two wks beginning at the start of treatment (d 0) and supplements were adjusted following BW measurement. Uterine and vaginal flushes were taken at d 0, 57, and 120 to determine cytokine and hormone presence. Mixed model ANOVA utilized fixed effects of treatment, day, and their interaction to analyze influence of GR on BW, BCS, average daily gain (ADG), and feed:gain (F:G). All BW were similar until the GR switch; CON and S/F decreased for 3 samples and then returned to similarity (P=0.06). ADG was lower in CON and S/F immediately following GR switch; however, all treatments were similar before and after this event (P=0.0054). All maintained similar F:G until F/S decreased after GR switch (P=0.01). Total F:G was similar for all treatments (CON=18.3, F/S=26.5, S/F=22.7; P=0.25) In conclusion, altering GR during development will allow producers to hit growth thresholds but may impact the uterine environment. We plan to further elucidate the immune profile via cytokine and hormone concentrations from uterine and vaginal flushes.
PSIV-12 Evaluation of reproductive performance and herd longevity when heifers grazing native range are vaccinated with a lifetime regimen of a killed viral or modified live viral vaccine
Authors: Melchior Emily A , Rosasco Shelby L , Lodge-Ivey Shanna L , Cox Shad H , Dunlap Richard L , Wenzel John C , Hallford Dennis L , Summers Adam F , Scholljegerdes Eric J
Published: November 2020

Fifty-eight Angus × Hereford cross heifers born in the spring of 2015 were randomly assigned to treatments of receiving a modified-live viral (MLV) or killed viral (KV) vaccination against bovine viral diarrhea virus (BVDV) at 60-d of age to determine the effects of vaccination on fertility and herd longevity. Heifers received vaccine treatments again at weaning (205d) at re-vaccination, and a yearly booster for the duration of their time in the herd. Blood samples were collected every two weeks prior to breeding to assess puberty attainment and were subsequently subjected to ovarian ultrasonography to measure antral follicle counts (AFC) and reproductive tract score (RTS). Heifers were synchronized utilizing the 7-d CIDR-PG protocol with AI following estrus detection. Heifer AFC, uterine horn diameter, RTS, and proportion of females attaining puberty before the breeding season were similar among treatments (P ≥ 0.38). Artificial insemination pregnancy rates, final pregnancy rates, and percentage of heifers that calved in the first 21 days were similar between vaccination treatment groups (P ≥ 0.19). Body condition score through the third parity at calving and weaning were not different between vaccination types (P ≥ 0.59). Females receiving a MLV vaccination remain in the herd in a similar proportion to those receiving a KV vaccination (P = 0.86). These results indicate that different vaccination strategies can be successfully used in beef cattle grazing native range without impacting fertility, or herd longevity.
PSIV-9 Effects of polyamines and trenbolone acetate on proliferation rates of murine myoblasts
Authors: Smith Laura A , Ineck Nikole E , Udy Brynne A , Erickson Chris L , Thornton Kara J
Published: November 2020

Androgens, such as testosterone, increase growth of skeletal muscle, although the exact mechanism through which these molecules function to increase growth of skeletal muscle remains unknown. Recent research indicates that one of the mechanisms through which androgens improve skeletal muscle growth is by modulation of the polyamine biosynthetic pathway. Polyamines are naturally occurring amino acid derivatives that are found in many whole foods and are potent stimulators of cell proliferation. However, the effect that polyamines have on growth of skeletal muscle has not been well characterized. The objective of this study was to investigate the effect that trenbolone acetate (a testosterone analog, TBA), polyamines (putrescine, spermine, and spermidine), and polyamine precursors (methionine and ornithine) have on proliferation of Sol8 and C2C12 murine myoblasts. Cultures were treated with 1% fetal bovine serum and 10 nM TBA, 10 mM methionine, 8 mM ornithine, 3 mM putrescine, 1.5 mM spermidine, or 0.1 mM spermine and proliferation rates were compared to a control (1% fetal bovine serum). Sol8 cells that were treated with 10 nM TBA, 10 mM methionine, 8 mM ornithine, 3 mM putrescine, 1.5 mM spermidine, or 0.1 mM spermine had increased (P < 0.05) proliferation rates compared to the control. C2C12 cells that were treated with 10 nM TBA or 10 mM methionine had increased (P < 0.05) proliferation rates compared to the control. This research demonstrates that TBA, some polyamines, and some polyamine precursors increase proliferation of myoblasts and thus, are capable of enhancing the rate of skeletal muscle growth. However, further research is needed to understand the relationship between androgens and the polyamine biosynthetic pathway relative to skeletal muscle growth.
PSIV-10 Effects of stair-step vs. constant supplementation amount on growth, reproduction, and intravaginal temperature in Bos indicus-influenced beef heifers
Authors: Palmer Elizabeth A , Oliveira Rhaiza A , Binelli Mario , Martins Thiago , Vendramini João , Moriel Philipe
Published: November 2020

This study investigated growth and reproductive performance of Bos indicus-influenced beef heifers provided a concentrate supplement at either a constant or stair-step supplementation. Sixty-four Brangus heifers were stratified by initial BW and age (255 ± 20 kg; 270 ± 22 d) and assigned to 1 of 16 bahiagrass pastures (4 heifers/pasture). Treatments were randomly assigned to pastures (8 pastures/treatment) and consisted of concentrate DM supplementation at: (1) 1.50% of BW from d 0 to 100 (CON) and (2) 1.05% of BW from d 0 to 49 and 1.95% of BW from d 50 to 100 (STP). Supplementation started on d 0 and continued until start of estrous synchronization on d 100. Intravaginal temperatures (16 heifers/treatment) were collected every 30 minutes from d 25 to 31 (September) and d 85 to 91 (November). All heifers were provided supplement at 1.50% of BW from d 101 to 211. Heifers were bred by AI from d 113 to 115 and Brangus bulls were placed with heifers from d 121 to 211. Data were analyzed using the MIXED procedure of SAS with treatment, time, and interaction as fixed effects. From d 0 to 49, ADG did not differ (P = 0.87); however, STP heifers had greater (P = 0.01; 0.73 vs. 0.56 kg/d) ADG from d 50 to 100 compared to CON heifers. Percentage of pubertal heifers, percentage of heifers in estrus, or reproductive tract scores did not differ between treatments (P ≥ 0.40). Intravaginal temperatures were greater (P < 0.0001) for CON vs. STP heifers from d 25 to 31 but did not differ (P = 0.74) from d 85 to 91. Using a stair-step vs. constant supplementation amount (1.05 to 1.95% vs. 1.50% of BW) before the breeding season reduced intravaginal temperatures and increased overall ADG in Bos indicus-influenced beef heifers.
PSIV-28 Program Chair Poster Pick: The Effects of Poor Maternal Nutrition During Gestation on Ewe and Offspring Plasma Concentrations of Leptin and Ghrelin
Authors: Soranno Lauren M , Jones Amanda , Pillai Sambhu , Hoffman Maria L , Zinn Steven A , Govoni Kristen E , Reed Sarah A
Published: November 2020

Poor maternal nutrition (restricted- and over-feeding) during gestation may alter leptin and ghrelin, key hormones in energy homeostasis and appetite control. They may also have a regulatory role in maternal metabolic adaptations critical during gestation to ensure optimal offspring growth and development. We hypothesized that restricted- and over-feeding during gestation would alter plasma concentrations of leptin and ghrelin in ewes and their offspring. Pregnant Western White-faced ewes were individually fed 60% (RES; n = 13), 100% (CON; n = 11), or 140% (OVER; n = 13) of NRC requirements for TDN starting on d 30±0.02 of gestation. Blood samples were collected in the morning from fasted pregnant ewes weekly from d 20 of gestation until parturition and from offspring (n = 31) within 24 hours after birth. Leptin and ghrelin concentrations were determined by radioimmunoassay. Data were analyzed using the MIXED procedure in SAS with main effects of treatment, day of gestation and their interaction. Leptin (P < 0.002) and ghrelin (P < 0.015) concentrations were altered in pregnant ewes between treatments within a day of gestation. At d 100 (P = 0.008) and d 128 (P = 0.04), RES ewes (5.392.58 ng/mL; 6.392.50 ng/mL) had decreased leptin concentrations compared with OVER ewes (14.972.48 ng/mL; 13.612.47 ng/mL), with CON ewes intermediate. RES ewes (0.260.04 ng/mL) had increased ghrelin concentrations compared with CON ewes at d 142 (0.150.04 ng/mL; P = 0.042), with OVER ewes intermediate. Leptin (P < 0.002) and ghrelin (P < 0.015) concentrations were altered between days of gestation within a dietary treatment. Leptin concentration increased across gestation in OVER ewes. In RES ewes, leptin concentration decreased and ghrelin concentration increased over gestation. Leptin (P = 0.5) and ghrelin (P = 0.5) concentrations in lambs were not different at birth. Alterations in leptin and ghrelin in ewes during gestation may disrupt critical metabolic adaptations that may contribute to suboptimal offspring growth and development.
PSVII-22 Using GPS and genomic technologies to provide a more accurate estimate of bull power in western intermountain beef systems
Authors: Garcia Matthew D , Chapman Kim , Heaton Kevin , Thacker Eric , Rickords Lee , Dallin Josh , Rood Kerry , Hadfield Jacob , Larsen Ryan
Published: November 2020

The objective of this study was to utilize GPS technology and genomic parentage testing to provide a more accurate measurement of bull power in Intermountain West beef production systems. Breeding seasons in the Intermountain West are typically conducted on expansive pastures, leading to current bull:cow ratios (1:20 or 1:25) possibly being inaccurate. Traditionally, producers maintain enough bulls to satisfy established bull cow ratios, but there was not further investigation into which calves were sired from specific bulls or how many cows each bull was actually servicing. Thus, the current study fitted five bulls with GPS collars and collected hair samples for future DNA extraction prior to the 2018 breeding season. Bull movement was tracked over a 90-day breeding season on a large grazing allotment in southern Utah and northern Arizona. The GPS collars allowed for tracking total distance traveled per day, and distance traveled away from water. Upon completion of the breeding season, collars were removed and data downloaded. A total of 104 potential offspring of the collared bulls were branded, and had ear notches collected for DNA extraction and parentage analyses. Results of parentage testing revealed that actually six bulls sired calves during the 2018 breeding season. The cooperating ranch’s bulls sired 30, 16, 14, 10 and 2 calves respectively. However, a neighboring operation’s bull sired 32 calves in the cooperator’s herd during that same season. While results from the current study are very preliminary, they do validate the importance of verifying bull power and sire identification in order to critically evaluate sire performance and increase the accuracy of selection in breeding replacements. The information presented herein may prove useful as a future selection tool to identify bulls that are high performers during the breeding season in the Intermountain West.
PSVII-8 Equations for prediction of empty body weight of water buffaloes finished in feedlot
Authors: Jorge Andre M , Francisco Caroline L , Castilhos André M , Martins Narciso Matheus Henrique P , Jacaúna Amanna G , Marques da Silva Daiane C , Aranha Aline S
Published: November 2020

This study aimed to develop equations to predict the empty body weight (EBW) using the shrunk body weight (SBW) of water buffaloes of three genetic groups (GG:Jafarabadi, Mediterranean, and Murrah; n = 65 for each GG), considering possible variations among GG. One-hundred-ninety-five non-castrated males (390±32 days of age; 327±51.96 kg of initial body weight - BW) from two years of similar experiments were used. Animals of each GG were allocated in collective pens for 28 days of adaptation period. Diet and water were offered ad libitum. Animal SBW were recorded at the beginning and every 28 days until the averages SBW reached the values determined (420, 480, and 540kg of SBW). After slaughter and to obtain the EBW, the non-carcass components of each animal [blood, paws, head, leather, tail, gastrointestinal tract (GIT), liver, kidneys, internal fat, and other internal organs] were weighed. The full GIT of each animal was weighed to obtain the total weight, and then emptied, washed, drained, and weighed to obtain the weight of the GIT content. Initially, data were analyzed using UNIVARIATE procedure in SAS. SBW recorded prior to slaughter were categorized according to SBW proposed considering the coefficient of variation below 10% for each GG to increase the precision of the data used, which decreased the initial n to 104 animals. Equations were developed and tested for GG effect using GLM and REG procedures in SAS. Tendency of GG effect was detected (P = 0.06). Thus, different prediction equations were determined for each GG, and a general prediction equation was developed for the three GG (Table 1). In conclusion, the results suggest it is possible to use distinct equations to predict the EBW according to GG as well as a general equation can be also used, resulting in high predictions of EBW of water buffaloes finished in feedlot.
PSVI-32 The effects of varying amylose levels in different diets on digestibility and glycemic response in canines
Authors: Quilliam Chloe , Ren Yikai , Morris Tressa , Ai Yongfeng , Weber Lynn P
Published: November 2020

This study was conducted to compare the digestibility of pulse-based diets to grain-based diets based on varying levels of amylose and study how changes in digestibility impacts glycemic response in dogs. To establish glycemic response, six diets were formulated at an inclusion level of 20% available starch with varying amylose content. A grain-based diet was formulated using rice, while pulse-based diets consisted of smooth pea, wrinkled pea (4140–4 and Amigold varieties), faba bean, or lentil. Beagles (n = 8, 4 females, 4 males) were fed the 6 different test diets for 7 days in a randomized, cross-over, blinded design. At the end of each feeding period, fecal samples were collected and beagles were fasted overnight and subjected to a glycemic test (1g/kg of diet or glucose fed). Data collected were statistically analyzed using SigmaPlot 12.0 and significance was declared at P ≤ 0.05. Amylose levels of diets varied from 4.64% to 14.82% on a dry basis. The rice-based diet had the lowest amylose content, while the wrinkled pea (Amigold variety) diet had the highest amylose content. Following the collection of glycemic response and fecal data, repeated-measures, 1-way ANOVA’s were conducted. There were significant differences observed between diets based on peak glucose levels (mmol/L, P = 0.01). The rice diet had the highest peak in glucose, while the lentil-based diet had the lowest glucose peak. Significant differences were also seen between diets based on their digestibility (P < 0.001). Rice, lentil, faba bean and smooth pea-based diets had the highest levels of digestibility, while wrinkled pea varieties had decreased digestibility. Furthermore, varying amylose found in diets can be viewed as an impacting factor on glycemic response and digestibility. Incorporating pulses with higher amounts of amylose could be utilized in dog diets to promote a low glycemic response through decreased rates of digestibility.
PSVI-24 Immunological Effects of a Purified 1,3/1,6 β-glucan Supplementation in Retorted Canine Diets
Authors: Traughber Zac , He Fei , de Godoy Maria R C
Published: November 2020

Yeast cell wall products are common functional ingredients capable of “priming” the immune system, specifically in reference to vaccine efficacy. Twenty-four adult, female Beagles were used in a completely randomized design. Three retorted diets were used: control diet (CON), CON plus β-glucan top-dressed daily upon time of feeding (C+B), and CON plus retorted β-glucan included in diet formulation (BG). Following a 7 d adaptation to CON, dogs were fed their respective treatment diets for 42 d and were challenged with an oral Bordetella bronchiseptica vaccine on d 14 with blood collections on d 0, 21, 28, and 42. The objectives of the present study were 1) to evaluate the effects of dietary inclusion of a yeast β-1,3/1,6 glucan (150 ppm) on apparent total tract digestibility (ATTD) of macronutrients, fecal microbiota, and peripheral blood mononuclear cells (PBMC; T-cells, B-cells, and monocytes) of adult dogs and, 2) to test the effects of retorting on the efficacy of these β-glucans. All diets were well-accepted by all dogs. ATTD of both dry matter and crude protein were greater (P < 0.05) for BG than CON and with greater (P < 0.05) energy digestibility for BG than both B+G and CON. Additionally, fecal short-chain and branched-chain fatty acids, ammonia, indole and phenol concentrations did not differ among treatments. No significant treatment by time interactions among treatment groups were observed for any analyzed PBMC. These data suggest that a 150 ppm inclusion of this yeast-derived β-glucan had no detrimental effects on ATTD, fecal characteristics and metabolites, nor any analyzed PBMC; however, due to the absence of differences in immune parameters among treatments, the effect of retorting on the efficacy of this product cannot confidently be assessed with these findings. Higher doses of yeast-derived β-glucan might be needed to elicit an immunological modulation in healthy adult dogs.
PSVI-31 The Effect of Aging on Peripheral Blood Mononuclear Cell Proliferation in Labrador Retrievers
Authors: Coon Craig N , Fowler Jason W , Varney Jessica L , Boggess Mary Ann
Published: November 2020

It is well documented that companion animals are living longer and as animals age their cells undergo immuno-aging or senescence, an age associated process of deterioration. In an effort to see how aging plays a role in immune cell proliferation, twelve healthy Labrador Retrievers (6-Young, 3Male/3Female, 6-Senior, 3Male/3Female) were selected to participate in a trial to determine what effect aging might have on the proliferative rate of peripheral blood mononuclear cells (PBMC). Mean age for Senior group was 8.74yrs, Young 2.38yrs (P.< 0.0001). Peripheral blood mononuclear cells (PBMC) were isolated, counted, seeded at a density of 5x104 in 96-well MP, cultured in RPMI-1640 complete medium (5% FBS), and mitogenic stimulation via 2-fold serial dilutions of Phytolacca Americana lectin (pokeweed mitogen-PWM) ranging from 0.8 -0.025 µg/mL. Following 48hr incubation in 5% CO2/95% humidity, 100µM Bromodeoxyuridine (5-bromo-2’-deoxyuridine, BrdU; a synthetic analog nucleoside of thymidine), was added to each culture well and further incubated 24hrs to allow DNA incorporation. Cells were harvested, denatured, and BrdU incorporated in newly synthesized DNA was bound by monoclonal antibodies (anti-BrdU-POD). The immune complexes were detected by tetramethyl-benzidine (TMB), reaction stopped with 1M Sulfuric acid (H2SO4), and quantified by measuring absorbance at 450nm. Proliferation was higher in Young dogs than Senior dogs at every concentration, signifying overall statistical significance (Mean: Young-0.972, Senior-0.697±0.057 SEM, P = 0.001). Rate difference by concentration was as follows: PWM 0.00 µg/mL: Young-0.109, Senior-0.194±0.031 (P = 0.099); 0.025 µg/mL: Young-0.788, Senior-0.481±0.201 (P = 0.321); 0.05 µg/mL: Young-1.002, Senior-0.610±0.207 (P = 0.227); 0.1 µg/mL: Young-1.113, Senior-0.776±0.195 (P = 0.244); 0.2 µg/mL: Young-1.249, Senior-0.915±0.172 (P = 0.217); 0.4 µg/mL: Young-1.271, Senior-0.965±0.148 (P = 0.191); 0.8 µg/mL: Young-1.252, Senior-0.936±0.117 (P = 0.101). These results coincide with other published literature, and these data suggest age plays a critical role in immunity and proliferative ability of PBMCs in the Labrador Retriever.