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Demonstrating the implementation of, and results from, applied management technologies on privately held farms is an essential method for Extension educators. A commercial cow/calf herd, for which the management was being transitioned to a younger family member, was used for this multi-year demonstration. Beginning summer 2019, the cow herd was inventoried and evaluated, and a plan was put in place to improve profitability through enhanced reproductive management. Initial evaluation showed an overall pregnancy rate of 75.6% with a 153 d calving season for cows and breeding age heifers (n = 209). Non-pregnant and un-sound cattle were sold (n = 56). The average initial BCS was a 4.5 (1 to 9 scale). Estrus synchronization for natural service was utilized in the first breeding season (Fall 2019) to condense the subsequent calving season. Melengestrol acetate (MGA) was fed at a rate of 0.5 mg/head/d for 7 d and bulls introduced on he last day MGA was fed. Also in year 1, timed artificial Insemination was used to breed purchased (n = 37) and home raised (n = 18) replacement heifers. A group of pregnant cows ranging in age from 5 to 8 years (n = 47) were also purchased in year 1. Ultrasonography was used to detect pregnancy and estimate calving date on 30 d post AI, and 30 d post bull removal. Year 2 pregnancy rate was 93% for heifers and 88% for cows with a 131 d estimated calving interval for all cows and heifers (n = 255), with 94% expected to calve in the first 90 days. In summary, while it is difficult to eliminate year-over-year variables, a combination of culling strategy and estrus synchronization for both natural service and AI resulted in an increased proportion of cows and heifers calving earlier in the calving season, which is expected to improve marketing potential and profitability of the resulting calf crop. Condensing the calving interval provides opportunity to introduce additional reproductive management practices. Results from this demonstration will be incorporated into Extension educational curricula.

With the objective of continuing educational delivery while county Extension offices were unable to host large group meeting due to pandemic response regulations, a series of webinars were developed as a component of the Tennessee Master Beef Producer program. A secondary objective was to maintain a county-based approach to programmatic delivery. To reach these objectives, individual webinars (Zoom Video Communications, San Jose, CA; n = 9), each lasting approximately 1.5 hr were developed by UT Extension Specialists and offered between October and November of 2020 covering the topics of breeding and genetics, reproductive management, nutrition, animal handling, economics, health management, and forages. Questions were administered during the live session via the Zoom polling function to assess production statistics and collect evaluation data. The series was advertised in local communities through UT Extension County Agents. Agents were given the opportunity to choose as many or as few to incorporate into their local delivery and could choose to give producers the option of viewing at home, at socially distanced group meetings, or either. Interaction was limited to the chat function within Zoom with the expectation that attendees would make audio and video interaction difficult to manage. Total live participation was 8,009 and averaged 890 ± 15.3 unique views per session. Each webinar was recorded and posted to YouTube to be used by agents for later delivery. In-webinar polling showed that an average of 91% of the webinar participants planned to implement a change on their operation as a direct result of information provided in the presentation. Post-webinar Likert scale (1 to 5) analysis of participants indicated approval of speaker ability (4.52 ± 0.03) and content quality (4.51 ± 0.03). These results indicate a high adoption rate by agents and that webinars are an effective tool for achieving behavioral change through a county-based Extension system.

The development of replacement heifers is crucial for breeding success and herd efficiency. Nutritional management can affect not only reproductive development but also the inflammatory status of the uterine environment, which may impact reproductive functions such as pregnancy establishment and development. The study herein evaluated the concentration of cytokines and chemokines in the uterus of heifers supplemented with different levels of protein. Angus heifers (n = 60) were blocked by body weight (BW) and randomly assigned to 1 of 3 treatments based on protein supplementation level: control of 10% crude protein (CON), 20% crude protein (P20), or 40% crude protein (P40). BW, body condition score, and blood samples were taken every 2 wk for 140 d to monitor development. Uterine flushes were performed monthly and concentrations of cytokines (IL-1α, IL-1β, TNF-α, IFN-γ, IL-10, VEGF-α, IL-17A, and IL-36RA) and chemokines (IL-8, MCP-1, MIP-1α, and MIP-1β) were quantified via ELISA multiplex. To test if there were mean differences in cytokines between the treatment groups or over time, PROC GLIMMIX (SAS v 9.4) was utilized. Concentrations of all cytokines and chemokines, except IL-1α, changed throughout heifer development (P < 0.05). Heifers in the P40 treatment group displayed reduced concentrations of MCP-1 (P = 0.007) and tended to have decreased concentrations of IFN-γ (P = 0.06). Cytokine IL-36RA tended (P = 0.06) to be affected by protein level, with the lowest concentrations observed in CON heifers. Most cytokines and chemokines increased following the initial month of supplementation (P < 0.05). The increase in concentrations after 1 mo may indicate an adaptive response in the uterus to diet change. Cytokines and chemokines fluctuated due to physiological changes occurring during development. Further research is needed to determine the influence of nutrition on uterine inflammation and long-term impacts on reproductive function.

Developing livestock and equine trainings to empower county Extension agents is challenging, especially when spanning in-person and online delivery modules. Real life application of training concepts is difficult, particularly when participants have varied backgrounds and experience. Thus, we assessed if scenario-based training modules were an effective training method across in-person and virtual formats. The same scenario-based training was delivered at three, regional in-person trainings (n = 42), and one virtual training (n = 32). Training format consisted of four, species-specific lectures addressing various production topics. Small groups then developed recommendations for a specific scenario, followed by a debriefing session consisting of group reactions and specialist recommendations. Topic-area application to county programs, instructor effectiveness, and overall benefit of the training session were evaluated (Qualtrics, in-person n = 26, 62% completion; virtual n = 17, 53% completion). Data were assessed using analysis of variance and mean comparisons (α=0.05), with Tukey’s pairwise post hoc analysis where appropriate (STATA 16). Across all sessions, likert scale responses (1=poor and 5=excellent, n = 43) indicated lecture sessions were applicable to county areas of need across material content (mean±SD, cattle=4.71±0.57, equine=4.64±0.50), teaching effectiveness (cattle=4.77±0.42, equine=4.75±0.43), and overall quality (cattle=4.68±0.57, equine=4.67±0.51), respectively. Scenario-based training benefit was not influenced by the number of times an agent had attended in-service training on livestock species, agent appointment (youth vs. adult educator), or training location (p >0.05). Attendance at previous in-service trainings (cattle P = 0.005; equine P = 0.013) and agent appointment (cattle P = 0.0006; equine P = 0.05) had a significant impact on the number of questions agents reported to have received on scenario topics in the last 12 months. More topic area questions were reported by agents with adult education responsibilities and previous training attendance. Based upon these results, scenario-based training is an effective in-person and virtual training tool for 4-H and adult Extension agents of varying experience.

The use of high-energy diets to develop bulls is perceived to influence semen quality, yet little research has been conducted using iso-caloric diets that differ in form or feeding management strategy. Therefore, the objective of this experiment was to evaluate the effects of two feeding strategies on growth performance and semen quality of developing bulls. Angus bulls (n = 48; 332 ± 47 d of age) were stratified into one of sixteen drylot pens before pens were randomly assigned to one of two iso-caloric diets: a total mixed ration (TMR; n = 8 pens) or a component-based ration (COMP; n = 8 pens) fed for 84 d. Rumen pH was continuously monitored via rumen boluses and dry matter intake (DMI) was measured daily throughout the experiment. Backfat thickness and hoof conformation were measured on d 0 and 84, with body weight measured and semen collected at 21-d intervals. Semen was assessed for progressive motility, total sperm per ejaculate, and sperm cell morphology. Data were analyzed via ANOVA utilizing JMP 13.0. Bulls fed the COMP ration had a greater DMI (P < 0.01) and ADG (P < 0.01), but similar feed efficiency (P = 0.21) when compared to TMR-fed bulls. Bulls fed COMP tended to have a lower mean rumen pH (P < 0.10). Additionally, COMP-fed bulls had greater backfat thickness (P < 0.01) but similar hoof conformation scores (P = 0.26) when compared to TMR-fed bulls on d 84. Feeding strategy did not affect progressive motility (P = 0.34), total sperm per ejaculate (P = 0.81), or percent morphologically-normal sperm (P = 0.31). These results suggest that the feeding strategies utilized in this experiment affected growth performance, rumen pH, and adiposity without influencing semen quality of developing bulls, and therefore should not be expected to influence breeding soundness examination outcomes.

Nutrition is a major component in successful heifer development, influencing age at puberty and the uterine environment, therefore, impacting reproductive efficiency. Different diets can influence systemic inflammation, however, the effect on uterine cytokines has not been determined. Our objective was to evaluate the effect of varied levels of dietary protein on inflammatory cytokines in the uterine environment of developing heifers. Commercial Angus heifers (n = 60) were blocked by body weight, then allocated to receive one of three dietary protein supplementation treatments (n = 20 per group, n = 5 per pen): 10% crude protein (CP; 100% corn), 20% CP [75% dried distillers’ grains (DDG) 25% corn], or 40% CP (75% soybean meal 25% DDG). Supplements were provided four times weekly for six months with ad libitum native grass hay, mineral supplement, and water. Body weight, BCS, and blood was taken every 14d. Uterine fluid was collected every 28d to determine presence of cytokines IL1α, IL1β, TNFα, IFNγ, IL10, IL4, and IL6. The GLIMMIX procedure (SAS 9.4) was used with fixed effects of supplementation, month, and their interaction; random effects of block, interaction of block and supplementation, and heifer within the interaction; and repeated measure of month. Concentrations of IL1β, TNFα, IFNγ, and IL10 shifted throughout development (P < 0.0002). Cytokine IFNγ was also affected by month of development (P = 0.002) and tended (P = 0.06) to decrease as CP increased. Presence of each cytokine was then recorded as binary and analyzed by the frequency procedure (SAS 9.4) to determine a uterine cytokine profile. Pro-inflammatory cytokines IL1α, IL1β, and TNFα occurred together more frequently following the beginning of supplementation. In conclusion, inflammatory cytokines shift throughout heifer development, potentially leading to differences in future reproductive success. Further research is needed to determine the dietary influence for optimal uterine environment development.

Growing concern over breeding soundness examination failures has led to increased interest in identifying factors that may influence semen quality of developing bulls. An experiment was conducted to evaluate relationships between semen quality and scrotal circumference, adiposity, and rumen conditions of Angus bulls (n = 48; 332 ± 47 d of age) that were developed over an 84-d period. Bulls underwent breeding soundness examinations at each of four 21-d intervals. Backfat thickness was measured on d 0 and 84, and rumen pH and temperature were continuously monitored throughout the experiment via rumen boluses (eBolus; eCow, Devon, UK). Simple linear regression was conducted (JMP 13.0; SAS Institute Inc., Cary, NC) to determine independent relationships between semen characteristics and respective explanatory variables. Change in scrotal circumference between d 0 and 84 was directly related to change in percent morphologically-normal sperm (R2 = 0.12; P < 0.05), but no other semen quality characteristics (P ≥ 0.17). Change in backfat thickness throughout the experiment tended to be inversely related to change in percent morphologically-normal sperm (R2 = 0.06; P < 0.10), but was directly related to changes in semen volume (R2 = 0.10; P < 0.05) and total sperm per ejaculate (R2 = 0.12; P < 0.05), but not change in motility (P = 0.24). Mean rumen pH tended to be directly related to changes in semen volume (R2 = 0.07; P < 0.10) and total sperm per ejaculate (R2 = 0.07; P < 0.10), but not changes in motility (P = 0.28) or percent morphologically-normal sperm (P = 0.94). Mean rumen temperature was not related to any semen quality characteristics (P ≥ 0.15). Collectively, these results suggest that rumen pH, as well as changes in scrotal circumference and adiposity are related to and independently explain variation in semen quality of developing bulls.

Excitable cattle are dangerous to personnel and have reduced individual performance. The aim of this study was to 1) identify objective criteria for evaluating bull temperament and 2) examine relationships among temperament, behavior, and performance of bulls during an 84-d performance test. Angus bulls ( = 60) were reared in 6 pens based on BW and age. Pen scores (PS; 1 = docile and 5 = very aggressive) were assigned on d -1, 27, 55, and 83. Exit velocity (EV), BW, time to exit the chute, and order through the chute were recorded on d 0, 28, 56, and 84. The ADG was calculated for the 84-d test period, and ultrasound data and frame score calculations were recorded on d 84. Dataloggers measured steps taken, lying time, number of lying bouts, and lying bout duration of bulls ( = 27; 3 pens) from d 3 to 28 and d 59 to 84. Bulls with a d -1 PS of 1 or 2 were categorized as calm (PScalm; = 40), whereas bulls with a PS of 3 or 4 were categorized as excitable (PSexcitable; = 20). Bulls were separated into 2 groups based on the bottom 20 EV (EVcalm) and top 20 EV (EVexcitable) on d 0. Mixed model ANOVA (SAS 9.3) was used to compare groups for the two temperament assessment methods, behavior, and growth performance. Mean EV decreased ( < 0.05) by d 84. Total lying time from d 3 to 28 was greater ( < 0.05) for PScalm bulls when compared with PSexcitable bulls. However, total lying time from d 59 to 84 was greater ( < 0.05) for EVexcitable bulls when compared with EVcalm bulls. Regardless of initial contemporary group assignment, all bulls exited the chute slower ( < 0.001) on d 84 than on d 0. The PSexcitable bulls had greater ( < 0.01) frame scores and greater ADG than PScalm bulls. The PSexcitable bulls had more ( < 0.01) backfat than PScalm bulls. However, ribeye area was smaller ( < 0.01) in EVexcitable bulls than EVcalm bulls. Based on these results, bulls appeared to have habituated over the testing period. Additionally, the potential lack of innate temperament variation may have attributed to the little difference seen among the behavioral and performance data. Therefore, temperament should be reassessed within a novel environment with new handlers to differentiate between the bull's true temperament and its ability to habituate.

The primary objective of this study was to identify if reproductive tract size-position score (SPS) and estrus expression prior to artificial insemination (AI) influences concentration of pregnancy-associated glycoproteins (PAGs) and pregnancy success. Angus females (n = 1397) were FTAI’d to Angus sires at d 0 after estrus synchronization using a 7-day CO-Synch CIDR protocol. Reproductive tract SPS were assigned on d 0 as SPS1 as small and compact resting within the pelvic cavity; SPS2 as intermediate, resting partially outside the pelvic cavity; and SPS3 as larger and resting outside the pelvic cavity. Estrotect patches received scores on d 0 of 1 (< 25% activation), 2 (< 50% activation), 3 (< 75% activation), or 4 (>75% activation) where patch scores of 1 and 2 signified no estrus expression, whereas scores of 3 and 4 indicated estrus expression. Pregnancy diagnosis was performed by ultrasound on d 30 after FTAI and serum samples were also collected on d 30 of gestation for quantification of PAGs. SPS3 females were more likely to exhibit estrus compared to both SPS1 (P = 0.0107) and SPS2 (P = 0.0291) females (48.98% vs 35.42% and 37.98%, respectively). Circulating PAG concentrations were significantly higher among females that exhibited increased estrus intensity compared to females that exhibited no estrus activity (P = 0.0023). Reproductive tract SPS by PAGs was not significant when parity was included as a covariate in the model (P > 0.05). Pregnancy loss did not correlate with reproductive tract SPS or estrus expression (P > 0.05); however, females that exhibited estrus at TAI did have a significantly higher pregnancy rate at d 30 of gestation (P < 0.0001) and AI calving rate (P = 0.0280) compared to females that did not show estrus. In summary, estrus is associated with increased pregnancy rates and SPS3 females exhibited estrus more frequently.