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Simple Summary: Supplementing trace minerals is common for managing bovine respiratory disease in developing beef cattle; however, its effects on their immune and metabolic systems are not fully understood. In this study, we evaluated three different mineral supplement programs and assessed their impact on the concentrations of copper, manganese, cobalt, and zinc, along with the whole blood gene expression, in high-risk beef cattle that remained clinically healthy over a 60-day period. Our results demonstrated that one supplement program, which included amino acid (organically) complexed minerals, led to an increase in gene activity related to adaptive immune system function and the metabolism of carbohydrates and fat-soluble vitamins compared to cattle-fed sulfate (inorganically) sourced complexed minerals. Additionally, the cattle given organically sourced minerals resulted in higher liver concentrations of copper at the end of the study compared to cattle given inorganically sourced minerals. This suggests that tailored mineral supplement programs may improve cattle immunity and mineral absorption. Understanding these effects improves how we manage cattle for diseases such as respiratory disease. Supplementing trace minerals is common in managing bovine respiratory disease (BRD) in post-weaned cattle; however, its influence on host immunity and metabolism in high-risk cattle remains unclear. We aimed to assess the impact of three supplementation programs on liver and serum trace element concentrations and blood gene expression. Fifty-six high-risk beef steers were randomly assigned to one of three groups over 60 days: (1) sulfate-sourced Cu, Co, Mn, and Zn (INR), (2) amino acid-complexed Cu, Mn, Co, and Zn (AAC), or (3) AAC plus trace mineral and vitamin drench (COMBO). Serum and liver biopsies for Cu, Co, Mn, and Zn at d0, d28, and d60 were analyzed from cattle free of BRD (n = 9 INR; n = 6 AAC; n = 10 COMBO). Differences and correlations of mineral concentrations were analyzed via generalized linear mixed models and Spearman's rank coefficients, respectively (p < 0.05). Whole blood RNA samples from healthy cattle (n = 4 INR; n = 4 AAC; n = 4 COMBO) at d0, d13, d28, d45, and d60 were sequenced and analyzed for differentially expressed genes (DEGs) via glmmSeq (FDR < 0.05), edgeR (FDR < 0.10), and Trendy (p < 0.10). Serum and liver Cu and Co concentrations increased over time in all groups, with higher liver Cu in COMBO (487.985 μg/g) versus AAC (392.043 μg/g) at d60 (p = 0.013). Serum and liver Cu concentrations (ρ = 0.579, p = 6.59 × 10−8) and serum and liver Co concentrations (ρ = 0.466, p = 2.80 × 10−5) were linearly correlated. Minimal gene expression differences were found between AAC versus COMBO (n = 2 DEGs) and INR versus COMBO (n = 0 DEGs) over time. AAC versus INR revealed 107 DEGs (d13–d60) with increased traits in AAC including metabolism of carbohydrates/fat-soluble vitamins, antigen presentation, ATPase activity, and B- and T-cell activation, while osteoclast differentiation and neutrophil degranulation decreased in AAC compared to INR. Our study identifies gene expression differences in high-risk cattle fed inorganic or amino acid-complexed mineral supplements, revealing adaptive immune and metabolic mechanisms that may be improved by organically sourced supplementation. [ABSTRACT FROM AUTHOR]

Accelerometers worn by animals produce distinct behavioral signatures, which can be classified accurately using machine learning methods such as random forest decision trees. The objective of this study was to identify accelerometer signal separation among parsimonious behaviors. We achieved this objective by (1) describing functional differences in accelerometer signals among discrete behaviors, (2) identifying the optimal window size for signal pre-processing, and (3) demonstrating the number of observations required to achieve the desired level of model accuracy,. Crossbred steers (Bos taurus indicus; n = 10) were fitted with GPS collars containing a video camera and tri-axial accelerometers (read-rate = 40 Hz). Distinct behaviors from accelerometer signals, particularly for grazing, were apparent because of the head-down posture. Increasing the smoothing window size to 10 s improved classification accuracy (p < 0.05), but reducing the number of observations below 50% resulted in a decrease in accuracy for all behaviors (p < 0.05). In-pasture observation increased accuracy and precision (0.05 and 0.08 percent, respectively) compared with animal-borne collar video observations. [ABSTRACT FROM AUTHOR]

With an audience of over 1 billion users per month, YouTube is an attractive medium for delivering Extension programming. Amidst growing competition for viewership, determining content that is in demand by Extension clientele on YouTube is a daunting challenge that Extension educators face. The YouTube Search function of Google Trends and monitoring of existing YouTube views for related content can help guide topic selection in developing Extension-authored video content. Example applications of these tools are detailed to show how to select relevant YouTube topics with viral appeal and extend the reach of Extension programming.

Item analysis can serve as a useful tool in improving multiple-choice questions used in Extension programming. It can identify gaps between instruction and assessment. An item analysis of Mississippi Master Cattle Producer program multiple-choice examination responses was performed to determine the difficulty of individual examinations, assess the effectiveness of distractors for individual items, and identify specific topics appropriate for placing further educational emphasis. Specific problems with items and distractors with examinations were identified and slated for revision. The item analysis results were then combined with program participant feedback to provide further insight into the instructional needs of Extension clientele.

This experiment compared performance, health, and physiological responses of high-risk stocker cattle receiving a Bacillus subtilis derivative during a 90-d grazing period. Crossbred steers (n = 120) were obtained from an auction yard and transported to the experimental facility. Steer shrunk body weight (BW) was recorded at arrival (d -1). This value was averaged with BW recorded on d 0 to represent initial BW (236 ± 2 kg). On d 0, steers were ranked by BW and allocated to 1 of 12 pastures (4-ha pastures; 10 steers/pasture). Pastures were randomly assigned to receive daily supplementation with dried distillers' grains at 1% of BW containing either: 1) Bacillus licheniformis and B. subtilis ingredient (BOV; 2 g/steer daily of Bovacillus, Chr Hansen A/S, Horsholm, Denmark) or 2) no additive (CON). Cattle received treatments from d 0 to 90 while housed in pastures containing stockpiled grass forage, as well as free-choice access to water and a commercial mineral + vitamin mix without ionophores. Steers were assessed for bovine respiratory disease (BRD) signs daily, and shrunk BW recorded on d 91. Blood samples were collected, and BW recorded on d 0, 14, 28, 56, and 90. No treatment differences were detected (P ≥ 0.19) for glucose, non-esterified fatty acids, P-hydroxybutyrate, haptoglobin, or insulin-like growth factor 1, whereas a treatment x day interaction indicated increased cortisol in BOV cattle on d 56 (P < 0.01). A treatment x day interaction was detected for serum concentrations of parainfluenza type 3 antibodies, which was greater in BOV steers on d 90 (P < 0.01). No treatment differences were detected (P ≥ 0.23) for serum concentrations of antibodies against other BRD pathogen. Average daily gain (ADG) tended to be increased (P = 0.09) in BOV compared with CON steers from d 56 to d 90 (0.858 and 0.760 kg/d, respectively, although did not impact overall ADG (P = 0.48). No treatment differences were detected for steer final BW (P = 0.43). Total BW change per pasture was greater in BOV compared with CON (790 vs. 550 kg BW change; P = 0.02). No treatment differences were detected (P = 1.00) for BRD incidence, although steers removed from the experiment for health reasons tended to be increased in CON compared with BOV (P = 0.08). Despite lacking differences in health or physiological responses, B. licheniformis and B. subtilis supplementation increased overall production of BW in high-risk stocker steers during a 90-d grazing period. [ABSTRACT FROM AUTHOR]

This experiment evaluated the impacts of supplementing organic complexed Cu, Co, Mn, and Zn on productive and health responses of high-risk beef cattle during a 60-d backgrounding phase. Crossbred steers (n = 120) were purchased at auction and transported to the experimental facility. Steer BW was recorded at arrival (d -1; initial shrunk BW = 227.7 ± 1.3 kg). On d 0, steers were ranked by BW and allocated to 1 of 8 groups (8 steers/group) and housed in drylot pens (6 m x 12 m) equipped with GrowSafe automated feeding systems (Model 8000; 2 bunks/pen; d 0 to 60). Groups were randomly assigned to receive a total mixed ration (TMR; 47% corn) containing: 1) sulfate sources of Cu, Co, Mn, and Zn (INR; n = 40); 2) organic complexed sources of Cu, Mn, Co, and Zn (AAC; Zinpro Availa 4; Zinpro Corp., Eden Prairie, MN; n = 40); or 3) AAC and an organic complexed trace mineral drench (APF; 30 mL/hd; Zinpro ProFusion, Zinpro Corp.) on d 0 and ancillary to morbidity treatment (n = 40). Diets provided the same daily amount of energy, protein, macro minerals and trace minerals based on 7 g/steer daily of Zinpro Availa 4. Steers were assessed for bovine respiratory disease (BRD) signs daily. Liver biopsies were performed on day 0, 28 and 60. Final BW was recorded on d 60 and 61. Blood samples were collected on d 0, 2, 6, 10, 13, 21, 28 and 45. No treatment differences were detected (P ≥ 0.23) for TMR intake, final BW, ADG, feed efficiency, or BRD incidence. Mean liver Co concentrations were greater (P = 0.02) in AAC and APF compared with INR steers. Mean liver Cu was greater (P = 0.02) in APF compared with AAC steers. Liver Zn tended to be greater (P = 0.10) on d 28 but less (P = 0.05) on d 60 for INR compared with AAC and APF steers. Plasma cortisol was least (P = 0.05) for steers supplemented with AAC on d 6, whereas AAC steers tended to have greater (P = 0.09) plasma cor-tisol on d 13 compared with APF. Plasma haptoglobin tended to be greater (P ≤ 0.10) for INR steers on d 28 and 45 compared with AAC and APF. While supplementing cattle with AAC or INR results in similar animal performance and clinical disease, AAC and APF reduces stress and acute phase protein responses. [ABSTRACT FROM AUTHOR]

While much research exists examining finishing cattle in conventional systems (confined cattle feeding, or feedlot systems), few data exist regarding finishing cattle in non-traditional systems, particularly in the micro-climates of the Gulf Coast. Non-traditional finishing systems feature additional variables and complexities versus feedlot finishing. The objective of this trial was to compare two non-traditional low input finishing cattle programs with a greater input traditional cattle finishing management program. Crossbred beef heifers [n = 12, initial body weight (BW) = 400 kg] were used to evaluate performance and cost of finishing beef cattle on limit-fed supplemental rations (CORN and SBH) compared with a totally mixed, free-choice ration (DIET). Animals were blocked by BW and randomly allotted to three treatments (CORN, n = 4; SBH, n = 4 and DIET n = 4). Two limit fed diets were combinations corn and a protein based mixing pellet (CORN) or soyhulls and a protein based mixing pellet (SBH), both fed at the rate of 1.9% of BW, while providing the heifers with free-choice access to bahiagrass (Paspalum notatum) forage during the summer months; DIET was a more conventional total mixed ration that provided both the concentrate and roughage component and included corn, soyhull pellets, mixing pellet, and cotton gin motes. Cattle were finished for 132 (n = 6) or 174 d (n = 6) and harvested at the MSU Meat Laboratory in Starkville located 235 miles from the trial location. Data were analyzed using MIXED procedure of SAS By design, dry matter intake during the entire finishing phase was greater (P = < 0.0001) for the free-choice DIET (10.8 kg. per day), compared with the limit fed diets (8.5 and 8.4 kg. per day). Overall average daily gain (ADG) was similar (P= 0.10) between both limit-fed diets (0.99 and 0.98 kg. per day for CORN and SBH). Average daily gain of cattle fed DIET (1.14 kg. per day) tended to be greater (P < 0.06) than both CORN and SBH diets. No differences were noted in G:F at any point during the study (P > 0.20). No differences (P > .0.05) were evident for slaughter weight, hot carcass weight, shrink, and dressing percentage among treatments. Total cost of gain for CORN and SOY were $1.74 and $1.65 cents per kilogram compared with DIET of $1.74 cents per kilogram (P = 0.76). Results indicate limit fed CORN and SBH diets could be a viable option to finish beef just as efficiently as a greater roughage total mixed ration (DIET). [ABSTRACT FROM AUTHOR]

This experiment compared performance, health, and physiological responses of weaned cattle receiving Bacillus subtilis derivative in a 90-d grazing period. Recently weaned Angus-influenced steers (n = 120) were obtained from an auction yard on d -1 and transported 150 km to research facility. Immediately after arrival on d -1, shrunk body weight (BW) was recorded and steers were grouped with access to native forage and water. On d 0, an additional body weight was recorded and combined with d -1 values to represent initial body weight (BW; 236 ± 2 kg). Steers were ranked according to initial BW and allocated to 1 of 12 pastures (4-ha pastures; 10 steers/pasture). Pastures were randomly assigned to receive daily supplementation with dried distillers grains at 1% of BW with either: 1) Bacillus subtilis ingredient (BOV; 2 g/steer daily of Bovacillus; Chr Hansen A/S, Horsholm, Denmark), or 2) no additive (CON). Cattle received treatments for the duration of the experiment (d 0 to d 90) while housed in pastures containing stockpiled native forage, primarily Cynodon dactylon and Paspalum dilatatum, as well as free-choice access to water and a commercial mineral + vitamin mix not including ionophores. Bovine respiratory disease (BRD) signs were assessed daily throughout the experimental period. Steer unshrunk BW was recorded on d 14, 28, 56, and 90 and shrunk BW recorded on d 91 added 8% shrink as final BW. Blood samples and fecal swabs were collected from all steers on d 0, 14, 28, 56, and 90. Average daily gain (ADG) was increased in BOV groups compared with CON (0.858 and 0.760 kg/d, respectively) from d 56 to d 90 (P = 0.09) although this BW gain was not sufficient to impact final BW. Steer BW did not differ between treatments for all days (P = 0.43). Incidence of BRD was within the expected range for high-risk stocker cattle, although the number of sick animals was not reduced due to BOV supplementation (P = 1.00). Steers not completing the trial due to health-related complications tended to be increased in CON vs. BOV (P = 0.08). Differences in percentage of steers not completing the experiment, in conjunction with treatment effects for ADG in the final third of the experiment, increased the production total BW per BOV pasture by 43% (790 vs. 550 kg BW change; P = 0.02). Bacillus subtilis supplementation was effective in increasing production BWt during a 90-d grazing period despite no observed difference in BRD incidence. [ABSTRACT FROM AUTHOR]

Researchers have investigated several factors that could alter fetal growth, including nutrient restriction (Valiente et al., 2021), hair shedding (Gray et al., 2011), and extreme hot and cold temperatures (Davidson et al., 2022). Hot temperatures and increased humidity percentages in the southeast United States caused researchers to investigate the hair coats of Angus cattle in the commercial production setting. An improvement in fiber digestibility and calf birth and weaning weights has been observed in Angus dams that shed 50% of the winter hair coat by May (Gray et al., 2011; Burnett et al., 2021). Our objective of this experiment was to investigate the nutrient digestibility of Angus calves born to cows that on average, shed early compared with calves from cows that shed later. Newly weaned, purebred Angus bull calves (early; n = 6, late; n = 6) were housed in metabolism crates for 10 d. Before the trial, calves had a 14-d adaption period to a 14% CP textured feed (CPC 14% Developer, CPC Commodities, Fountain Run, KY) and offered ad libitum Cynodon dactlyon hay and water. After 3 d crate acclimation period, urine, feces, orts, and hay samples were collected for 7 d. Concentrate was offered at 0.25% of average BW. Approximately 5% samples were taken of feces, and urine samples had 1 to 1.5% of 25% metaphosphoric acid added to prevent ammonia volatilization, and both collections were composited by animal. Orts were collected at 0600 h daily, dried, and composited by animal. Laboratory analysis included dry matter (DM), organic matter (OM), ash, neutral detergent fiber (NDF), acid detergent fiber (ADF), Kjeldahl N (CP), and fat. Data were analyzed using the GLM procedure of SAS 9.4 in a completely randomized design with calf as the experimental unit. Significant (P = 0.05) means were separated using Fischer's protected LSD. The model for intake included average daily DM and OM (kg) and adjusted by body weight (BW%). For digestibility analysis, the model included: DM, OM, ash, NDF, ADF, hemi-cellulose (HC), CP, and fat. The N retention model included: N retained (g/d), N retained/consumed (%), and N retained/DM intake (%). There were no differences between early or late calves for DM intake (5.502 ± 0.2774 kg/d; 2.251 ± 0.1247 %BW), or OM intake (5.199 ± 0.2591 kg/d; 2.128 ± 0.1166 %BW). There were no differences in digestibility for either group for DM, OM, Ash, NDF, ADF, HC, CP, or fat (Table 1.). There were also no differences in N retention in either group of calves (3.686 ± 2.0242 g/d; 4.366 ± 2.3964 %; 0.064 ± 0.0355 %). Further research is needed in this area to adequately understand factors influencing nutrient digestibility in calves born from early and late shedding dams. [ABSTRACT FROM AUTHOR]

As input costs increase, producers need to be mindful of management practices to maintain profit margins and it is important to understand current management practices. Therefore, the objective of this study was to investigate current beef marketing strategies and beliefs of beef producers in the state of Mississippi in 2019. This survey was distributed to cattle producers in Mississippi in the June/July issue of "Cattle Business in Mississippi" magazine with return postage. There also was a link included in the "Monday Memo" email sent to members of the Mississippi Cattlemen's Association. The survey consisted of 22 questions that were divided into three sections: current practices, current cow-calf marketing practice, and general information. Responses from the survey were anonymous and confidential and were received via paper mail or electronic responses. Responses were stored and analyzed using Qualtrics. Data collected from this study were compared with 1999 data from a similar study conducted by Little et al. (2000). Out of 148 respondents, there was a 95% completion rate of surveys taken. Most respondents were 51 years and older with 54% of the respondents being part of the cattle industry for over 31 years. Ninety percent of respondents were members of the Mississippi Cattlemen's Association and almost 60% were certified in Beef Quality Assurance. The majority, 122 of 148 producers, stated their cattle operation was not the primary source of income for their household. The average number of cows, bulls, stockers/yearling, replacement heifers and cattle on-feed on an operation was greater in the 2019 data compared with 1999. On average, the number of cows per operation increased from 40 to 68 animals, bulls increased from 2 to 5 animals, and replacement heifers increased from 7 to 17 animals from 1999 to 2019. There was also an average increase from 30 to76 animals of stocker/yearling and an increase from 2 to 27 animals of on-feed cattle. Most producers vaccinate (81%) and deworm (85%) according to recommendations and indicated a lack of labor and time as reasons for not implementing some common management practices such as preconditioning. Respondents mainly purchased calves directly from a producer (61%) or from special sales (59%). In 1999, over one-half of respondents purchased from an auction. When it came to selling cattle, 58% of respondents sold at auction regularly in 2019. In 1999, 73% of respondents sold at auctions. In 2019, 72% of respondents stated they did not retain ownership while in 1999 only 58% of respondents did not retain ownership. In conclusion, our results suggest there have been key changes within the cattle industry regarding herd size increases and a shift in selling and purchasing habits since 1999. [ABSTRACT FROM AUTHOR]

Energy budgets in grazing cattle are notoriously difficult to study given complex environmental and physiological interactions between plants and animals, each operating according to individual grazing budgets. However, these synergistic energy pathways can be modeled using a series of mechanistic relationships describing forage resource distribution and animal behavior, each which can be observed with high levels of accuracy and precision using biometric sensors and remote sensing technology. The objective of this study is to demonstrate the coordination of data inputs into a coherent framework utilizing biometric and remote sensing technology. Crossbred steers (n = 10) were fitted with GPS and video tracking collars (Vectronic) and accelerometers (Wildbytes technologies), then managed for 286 days as part of a broader research grazing ecology project on pasture (~11.54 hectare) comprised of bermudagrass (Cynodon dactylon) and tall fescue (Festuca arundinacea) and equipped with an automated walk-over-weigh (TruTest) scale system. Distribution of forage quality was sampled monthly with a ½ m² quadrat using a 20 x 20-meter grid (n = 297) and remotely assessed via an unmanned aerial vehicle (Matrice 100) mounted hyperspectral camera (MicaSense) at 8 cm resolution. Animal behavior was predicted utilizing a trained randomforest prediction algorithm, and linked to geo-location and forage quality at the spatial-temporal scale in Program R. We then constructed animal ethogram, distribution of forage quality, and spatial-temporal distribution of animal behavior across the grazing landscape for a test period. We found steers allocated the greatest proportion of time to grazing and resting behaviors, 30 and 60% respectively, with the remainder dedicated to ruminating and walking behaviors. A diurnal, circadian rhythm in animal behavior demonstrates that steers grazed between 0900 and 1000 in the morning, and again between 1300 and 2000 in the evening, while resting behavior dominated the hours between 0300 and 0900, with a slight increase in grazing behavior noted at 0600, or approximately sunrise. Animal behavior linked forage availability showed steers selectively grazed areas with higher NDVI signatures, while seeking sources of water and cover to practice resting behavior. Given the need to develop robust models predicting forage intake and energy in grazing animals to improve sustainability and environmental metrics, animal tracking and biometric technologies offer a vital solution to improving management of extensively managed grazing livestock. [ABSTRACT FROM AUTHOR]