Almond hulls and shells as an alternative fiber source in limit-fed growing beef cattle diets.

Almond hulls and shells are a by-product of almond production that can be incorporated as a feed ingredient in beef cattle diets. Three experiments were conducted to determine the effects of hammermill screen size on almond hull and shell bulk density and inclusion of ground or non-ground almond hulls and shells in limit-fed growing diets on growth performance, diet digestibility, and ruminal fermentation characteristics of beef cattle. In experiment 1, almond hulls and shells were ground with a laboratory-scale hammermill using no screen, a 11.1-mm screen, a 19.1-mm screen, or a 25.4-mm screen. Each screen-size treatment was ground at three separate time points (n= 3 replications/treatment). Grinding almond hulls and shells with no screen increased bulk density by 111% and minimized proportions of fine particles; therefore, almond hulls and shells ground using no screen were included as a treatment in the following experiments. In experiment 2, 364 steers (initial body weight [BW]: 257±â€…20.7 kg) were blocked by truckload (n = 4), stratified by BW, and assigned to pen within block. Pens were randomly assigned to 1 of 4 experimental diets (n= 10 pens/treatment). The control diet (CON) contained (DM basis) 39.5% dry-rolled corn, 7.5% supplement, 40% wet-corn gluten feed, and 13% prairie hay. Non-ground (13AH) or ground (13GAH) almond hulls and shells replaced prairie hay and were fed at 13% of diet DM or non-ground almond hulls and shells were fed at 26% of diet DM and replaced 13% prairie hay and 13% dry-rolled corn (26AH). Diets were limit-fed at 2.2% of BW daily (DM basis) for 56 d. Overall average daily gains (ADG) were greater (P ≤ 0.05) for CON, 13AH, and 13GAH compared with 26AH. In addition, ADG from days 14 to 56 were greater (P= 0.03) for 13GAH and tended to be greater (P = 0.09) for 13AH compared with CON. Experiment 3 was a 4 × 4 replicated Latin square in which 8 ruminally cannulated heifers (initial BW = 378 ±â€…44.0 kg) were fed diets from experiment 2. Apparent dry matter digestibility did not differ (P = 0.21) among treatments. Total ruminal volatile fatty acid concentrations were greater (P ≤ 0.03) for 13GAH and 13AH compared with 26AH and tended (P = 0.06) to be greater for 13GAH compared with CON. Overall, almond hulls and shells can be utilized as an alternative to prairie hay in limit-fed growing diets without negatively influencing rates of gain or diet digestibility.

Effect of supplemental methionine on health and performance of receiving beef heifers.

Methionine supplementation can improve immune function in transition dairy cattle. Our objective was to determine if supplemental methionine could improve health and performance of newly received growing cattle. Crossbred heifers (n = 384; 222 kg initial body weight; southeastern U.S. origin) were received in four truckloads (blocks) over 9 d. Heifers were weighed at arrival. The following day (d 0) cattle were vaccinated for viral and clostridial diseases, received 2.5 mg tulathromycin/kg body weight, and were stratified within the blocks by arrival body weight to 1 of 8 pens containing 12 heifers each. Within blocks, pens were assigned to 1 of 2 treatments: 0 (control) or 0.1725% Smartamine M to provide 0.1035% metabolizable methionine to the diet. Cattle were limit-fed at 2.2% of body weight daily (dry matter basis) on a diet containing 40% wet corn gluten feed, 34.5% dry-rolled corn, 10% corn silage, 7.5% supplement, 4% alfalfa hay, and 4% prairie hay. Pen weights were measured weekly to determine the feed offered the following week. Individual body weight and tail-vein blood samples were collected on d 0, 14, and 45. Plasma haptoglobin was measured to assess acute-phase protein response. Incidences of morbidity (1.6% for control, 2.6% for Smartamine M) and mortality (0.5% for both control and Smartamine M) were low. Between d 0 and 45, no differences were observed for average daily gain (1.24 vs. 1.27 kg/d; control vs. Smartamine M, P = 0.55) or gain:feed (0.107 vs. 0.110, P = 0.28), although dry matter intake was 1.3% greater (P < 0.01) for control than Smartamine M due to differences in diet dry matter concentration. An interaction between treatment and linear effect of day was detected for plasma haptoglobin (P < 0.05); over time, haptoglobin increased more for control (2.15, 2.28, and 2.95 mg/mL at 0, 14, and 45 d) than for Smartamine M (2.35, 2.37, and 2.58 mg/mL). Supplemental methionine may alleviate acute-phase protein responses in stressed receiving cattle.

Bunk space requirements for growing beef cattle limit-fed a high-energy corn and corn co-product diet.

Bunk requirements for optimal growth performance of growing calves limit-fed high-energy corn and corn co-product diets have not been widely evaluated. Three-hundred eighty-five crossbred steers (initial body weight = 215 ± 25 kg) were purchased in Texas, transported to the Kansas State Beef Stocker Unit, and weighed at arrival. Steers were stratified by body weight and randomly assigned to 1 of 28 pens containing 12 to 14 head. Within block, pens were randomly assigned to one of four bunk allotment treatments: 25.4, 38.1, 50.8, or 63.5 cm of bunk per head for a 58-d receiving period. Calves were fed at 0700 h once daily at 1.8% of bodyweight (dry matter basis) from February 2 to March 13, 2021; thereafter the daily feed allotment was increased to 2.0% of bodyweight. The diet contained (dry matter basis) 39.5% dry-rolled corn, 7.5% supplement, 40% wet corn gluten feed, and 13% prairie hay. Steers were individually weighed on days 29 and 58 and pen weights were measured weekly to determine feed offered for the following week. Body weights on days 29 and 58, dry matter intake, or gain-to-feed ratio during the receiving period did not differ (P ≥ 0.34) between treatments. During the first 29 d, average daily gain (ADG) increased linearly as bunk space increased (P = 0.03); however, no treatment effects were observed thereafter. In addition, ADG standard deviation from days 0 to 29 responded quadratically (P = 0.05) where ADG standard deviation tended to be greater in the 38.1-cm allotment and was greater in the 50.8-cm allotment compared to the 25.4-cm allotment (P = 0.07 and P = 0.04, respectively). Bunk score tended to decrease linearly as bunk allotment decreased (P = 0.06). Following the receiving period, steers were blocked by bunk treatment and randomly assigned to 1 of 18 pastures. Steers were grazed for 90-d from May to August at a targeted stocking density of 280 kg live-weight ˖ ha-1. During the grazing season, ADG increased linearly with reduced (P < 0.01) bunk allotment; however, body weights did not differ (P = 0.91) between bunk treatments at the completion of the grazing period. In addition, overall total body weight gains and ADG from the receiving and grazing periods did not differ (P > 0.57) between bunk treatments. We interpreted our data to suggest that bunk space allotments of 25.4 to 63.5 cm per head had minimal impact on growth performance during a 58-d receiving period and did not affect final body weights following a 90-d grazing season.

Effects of feeding corn containing an alpha-amylase gene on the performance and digestibility of growing cattle.

Two growth performance studies and two digestibility trials were conducted to evaluate the effects of feeding Enogen Feed Corn silage and corn grain to growing cattle. In Exp. 1, there were a total of four diets offered for ad libitum intake. The four diets consisted of two varieties of corn (Enogen Feed Corn [EFC] vs. yellow #2 corn [CON]) with two different methods of corn processing (dry-rolled [DR] vs. whole-shelled [WS]) and were formulated to provide 1.13 Mcal NEg/kg dry matter (DM); corn grain was 28.6% of diet DM. Average daily gain (ADG) and ending body weight tended to be greater for calves fed EFC than for those fed CON (P < 0.10). Gain:feed (G:F) was better for calves fed EFC (P < 0.01), improving by 5.5% over calves fed CON. In Exp. 2, a digestibility trial was conducted using seven cannulated Holstein steers fed the same diets from Exp. 1. Ruminal pH was not affected by corn variety (P > 0.82). Liquid passage rate was greater for CON-fed calves and associated with lower digestibility. Total tract DM and organic matter (OM) digestibilities were greater for EFC-fed calves (P < 0.04). In Exp. 3, there were four diets offered for ad libitum intake. Dietary factors were arranged as a 2 × 2 factorial and consisted of two hybrids of corn silage (EFC silage [EFC-S] vs. control silage [CON-S]) and two varieties of corn grain (EFC grain [EFC-G] vs. control [CON-G]; both were dry-rolled). Diets were formulated to provide 1.11 Mcal NEg/kg DM; corn grain was 38.5% of diet DM, and corn silage was 40% of diet DM. ADG was 6.0% greater (P < 0.01) and G:F was numerically (P < 0.14) 3.3% greater for calves fed EFC-S than for those fed CON-S, but substituting EFC-G for CON-G did not affect ADG or G:F. In Exp. 4, a digestibility trial was conducted using eight cannulated beef steers fed the same diets as Exp. 3. Liquid passage rate (P > 0.20), ruminal pH (P > 0.23), and ruminal total volatile fatty acid concentrations (P > 0.27) were unaffected by treatment. Total tract digestibilities of DM and OM were numerically greater by 2.5% and 2.2%, respectively, for calves fed the EFC-S compared with those fed CON-S. Feeding a corn hybrid containing alpha-amylase enzyme improved G:F of growing calves. Feeding EFC can benefit the beef industry by allowing less processing of grain without sacrificing performance.

Assessment of pain associated with bovine respiratory disease and its mitigation with flunixin meglumine in cattle with induced bacterial pneumonia.

Pleuritic chest pain from bacterial pneumonia is often reported in human medicine. However, studies investigating pain associated with bovine respiratory disease (BRD) are lacking. The objectives of this study were to assess if bacterial pneumonia elicits a pain response in calves with experimentally induced BRD and to determine the analgesic effects of transdermally administered flunixin. A total of 26 calves, 6-7 mo of age, with no history of BRD were enrolled into one of three treatment groups: 1) experimentally induced BRD + transdermal flunixin at 3.3 mg/kg twice, 24 h apart (BRD + FTD); 2) experimentally induced BRD + placebo (BRD + PLBO); and 3) sham induction + placebo (CNTL + PLBO). Calves induced with BRD were inoculated with Mannheimia haemolytica via bronchoalveolar lavage. Outcomes were collected from -48 to 192 h post-treatment and included serum cortisol, infrared thermography, mechanical nociceptive threshold, substance P, kinematic gait analysis, visual analog scale (VAS), clinical illness score, computerized lung score, average activity and rumination level, prostaglandin E2 metabolite, plasma serum amyloid A, and rectal temperature. Outcomes were evaluated using either a generalized logistic mixed model for categorical variables or a generalized linear mixed model for continuous variables. Right front force differed by treatment (P = 0.01). The BRD + PLBO had lower mean force applied to the right front limb (85.5 kg) compared with BRD + FTD (96.5 kg; P < 0.01). Average VAS differed by a treatment by time interaction (P = 0.01). The VAS scores differed for BRD + PLBO at -48 (3.49 mm) compared with 168 and 192 h (13.49 and 13.64 mm, respectively) (P < 0.01). Activity for BRD + PLBO was higher at -48 h (27 min/h) compared with 48, 72, 120, and 168 h (≤ 22.24 min/h; P < 0.01). Activity differed by a treatment by time interaction (P = 0.01). Activity for BRD + FTD was higher at -48 and 0 h (28.2 and 28.2 min/h, respectively) compared to 48, 72, 96, and 168 h (≤23.7 min/h; P < 0.01). Results show a combination of reduced activity levels, decreased force on the right front limb, and increased VAS pain scores all support that bacterial pneumonia in cattle is painful. Differences in right front force indicate that flunixin transdermal may attenuate certain pain biomarkers in cattle with BRD. These findings suggest that BRD is painful and analgesic drugs may improve the humane aspects of care for cattle with BRD.

Assessment of diagnostic accuracy of biomarkers to assess lung consolidation in calves with induced bacterial pneumonia using receiver operating characteristic curves.

Bovine respiratory disease (BRD) is the most economically significant disease for cattle producers in the U.S. Cattle with advanced lung lesions at harvest have reduced average daily gain, yield grades, and carcass quality outcomes. The identification of biomarkers and clinical signs that accurately predict lung lesions could benefit livestock producers in determining a BRD prognosis. Receiver operating characteristic (ROC) curves are graphical plots that illustrate the diagnostic ability of a biomarker or clinical sign. Previously we used the area under the ROC curve (AUC) to identify cortisol, hair cortisol, and infrared thermography imaging as having acceptable (AUC > 0.7) diagnostic accuracy for detecting pain in cattle. Herein, we used ROC curves to assess the sensitivity and specificity of biomarkers and clinical signs associated with lung lesions after experimentally induced BRD. We hypothesized pain biomarkers and clinical signs assessed at specific time points after induction of BRD could be used to predict lung consolidation at necropsy. Lung consolidation of > 10% was retrospectively assigned at necropsy as a true positive indicator of BRD. Calves with a score of < 10% were considered negative for BRD. The biomarkers and clinical signs analyzed were serum cortisol; infrared thermography (IRT); mechanical nociceptive threshold (MNT); substance P; kinematic gait analysis; a visual analog scale (VAS); clinical illness score (CIS); computerized lung score (CLS); average activity levels; prostaglandin E2 metabolite (PGEM); serum amyloid A; and rectal temperature. A total of 5,122 biomarkers and clinical signs were collected from 26 calves, of which 18 were inoculated with M. haemolytica. All statistics were performed using JMP Pro 14.0. Results comparing calves with significant lung lesions to those without yielded the best diagnostic accuracy (AUC > 0.75) for right front stride length at 0 h; gait velocity at 32 h; VAS, CIS, average activity and rumination levels, step count, and rectal temperature, all at 48 h; PGEM at 72 h; gait distance at 120 h; cortisol at 168 h; and IRT, right front force and serum amyloid A, all at 192 h. These results show ROC analysis can be a useful indicator of the predictive value of pain biomarkers and clinical signs in cattle with induced bacterial pneumonia. AUC values for VAS score, average activity levels, step count, and rectal temperature seemed to yield good diagnostic accuracy (AUC > 0.75) at multiple time points, while MNT values, substance P concentrations, and CLS did not (all AUC values < 0.75).

Bovine respiratory disease (BRD) is the most economically significant disease for cattle producers in the United States, affecting 16.2% of cattle on feed. Cattle with advanced lung lesions at harvest have reduced average daily gain, yield grades, and carcass quality outcomes. The identification of biomarkers and clinical signs that accurately predict lung lesions could benefit livestock producers in determining a BRD prognosis. Herein, we used receiver operating characteristic curves to assess the predictive value of biomarkers and clinical signs associated with lung lesions after experimentally induced BRD. In the first 72 h after onset of BRD, right front stride length, gait velocity, visual analog scale score, clinical illness score, average activity level, step count, and rectal temperature yielded the best diagnostic accuracy (AUC > 0.75) for predicting calves with significant lung lesions (>10% consolidation) at necropsy. Biomarkers and clinical signs with the best diagnostic accuracy early in the disease process would likely be the most valuable in field conditions. These results can be used to guide refinement of the optimal time points and biomarkers for the diagnosis of significant lung lesions after BRD.

Effects of prescribed fire timing on grazing performance of yearling beef cattle, forage biomass accumulation, and plant community characteristics on native tallgrass prairie in the Kansas Flint Hills.

Recent research demonstrated that mid- or late-summer prescribed fires can be employed to manage sericea lespedeza (Lespedeza cuneata) infestations in the Kansas Flint Hills. The effects of prescribed fire applied during the growing season (i.e., August to October) on grazing performance of yearling cattle have not been evaluated. Native pastures (n = 18; 22 ± 4.0 ha) were grouped by watershed and assigned randomly to one of three prescribed-fire treatments: spring (7 April ± 2.1 d), summer (21 August ± 5.7 d), or autumn (2 October ± 9.9 d). Yearling beef cattle were grazed from May to August at a targeted stocking density of 280 kg live-weight/ha following prescribed-fire application. Forage biomass accumulations, soil cover, plant species composition, and root carbohydrate concentrations in four native plant species were evaluated. Total body weight (BW) gains and average daily gain were greater (P = 0.01) for cattle that grazed the spring and summer prescribed-fire treatments compared with those that grazed the autumn prescribed-fire treatment. As a result, final BW were greater (P = 0.04) in the spring and summer treatments than the autumn treatment. Conversely, forage biomass accumulations did not differ (P = 0.91) between fire regimes. Proportions of bare soil were greater (P < 0.01) in the spring treatment compared with the summer and autumn treatments, whereas proportions of litter on the soil surface were greater (P < 0.01) in summer- and autumn-burned pastures compared with spring-burned pastures. Total basal cover of graminoids and forbs did not differ (P ≤ 0.15) between prescribed fire treatments. Likewise, total basal cover of C3 or C4 perennial grasses did not differ (P ≥ 0.23) between prescribed-fire treatments. No treatment differences (P = 0.24) in root starch or root water-soluble carbohydrate concentrations in big bluestem (Andropogon gerardii), little bluestem (Schizachyrium scoparium), Indiangrass (Sorghastrum nutans), or purple prairieclover (Dalea purpurea) were detected. These data were interpreted to suggest that summer or autumn prescribed fire can be applied without reducing forage biomass accumulations, root carbohydrate concentrations in key native plant species, or considerably altering native plant populations compared with conventional spring-season prescribed fire; however, summer prescribed fire could be favored over spring or autumn prescribed fire both to maintain stocker cattle growth performance and to achieve control over sericea lespedeza.

Effects of dietary energy level and intake of corn by-product-based diets on newly received growing cattle: antibody production, acute phase protein response, stress, and immunocompetency of healthy and morbid animals.

Effects of dietary energy level and intake of corn by-product-based diets on antibody production, acute phase protein response, stress, and immunocompetency of healthy and morbid newly received growing cattle were evaluated. Four dietary treatments were formulated to supply 0.99, 1.10, 1.21, and 1.32 Mcal NEg/ kg DM and were offered at 100%, 95%, 90%, and 85% of ad libitum based on 0.99/100 treatment intake, respectively. Thirty-two pens were utilized with approximately 12 animals/pen. Four animals from each pen (32/dietary treatment) were randomly selected and used to serve as a subset to monitor immune function and acute phase proteins following a split-plot design. In addition, two animals were randomly and independently selected from each pen (16/dietary treatment) and used to measure fecal cortisol metabolite. Additionally, animals removed from the pen one (M1), two (M2), or three (M3) times and classified as morbid were bled in conjunction with a healthy control (H) removed at the same time and the serum analyzed for the same parameters. A quadratic response to time (P < 0.01) was detected for haptoglobin concentrations and for antibody titers for bovine viral diarrhea type 1 (BVD-I) and infectious bovine rhinotracheitis (IBR; P < 0.01). Haptoglobin was lowest on arrival, highest on day 14, and similar to baseline levels by day 27. Titer levels for BVD-I and IBR were lowest on arrival, higher on day 14, and significantly higher on day 27. Titers for bovine viral diarrhea type 2 (BVD-II) responded linearly (P < 0.05) with lower levels on arrival and highest levels on day 27. Haptoglobin was elevated in morbid animals compared to healthy pen mates (P < 0.05). Titer levels for BVD-I and IBR were also higher in healthy animals compared to animals pulled for morbidity (P < 0.01). Fecal cortisol was higher on arrival than on day 14 (P < 0.05). Dietary treatment had no effect on any of the parameters investigated. In summary, high-energy receiving diets based on fermentable fiber from by-products can be fed to newly received growing cattle without negative effects on antibody production toward vaccines, inflammation, or overall stress. In addition, haptoglobin concentrations and titer levels for BVD-I and IBR viruses are higher in healthy animals compared to sick animals.

A field study evaluating health, performance, and behavior differences in crossbred beef calves administered different vaccine-parasiticide product combinations.

Bovine respiratory disease complex (BRDC) is the most important health issue in beef feeder calves. Our study was a randomized, blinded field trial to evaluate potential differences in health, production and behavior in feeder calves administered two different preventive health programs. Calves in two replicates (n=308 and n=305) were allocated to pens and then pens were randomly assigned a preventive health program. One program (Prog1) consisted of 1 injectable clostridial vaccine, 1 intranasal modified live respiratory vaccine, 1 topical and 1 oral parasiticide. The other program (Prog2) consisted of 1 injectable clostridial vaccine, 1 modified live respiratory vaccine and 1 injectable parasiticide. A greater percentage of calves in Prog1 (59.7%) experienced BRDC morbidity compared to the Prog2 program (47.8%). There were no differences between programs in mortality, case fatality, 1st treatment success or chronicity risks. The average daily gain over the entire study period for the Prog2 calves (1.23 kg) was greater than the Prog1 calves (1.16 kg). Calves administered Prog1 on average took more steps each day during the first 28 days of the study. Additionally, Prog1 calves spent more time lying down on certain days during the last 14 days of the study. During initial program administration, fewer Prog1 calves (39.8%) vocalized compared to Prog2 calves (47.8%). In this study, calves administered a program with fewer injections indicated less aversion to program administration than those administered more injections, but experienced greater morbidity and poorer performance.

Record systems for beef stocker production enterprises.

The accelerated growth of individual animal identification systems is likely to generate significant amounts of data that need to be synchronized, filtered, analyzed, managed, and acted on in real time by data-mining software and animal health professionals who possess a dual understanding of beef systems production and technology associated with management information and record-keeping systems. Ultimately, the resulting information can be used seamlessly throughout a vertically coordinated production system to conduct management and animal health compliance audits, initiate timely animal and product recall measures, and reveal complex biologic and economic relations.