bluuebunny/crossref_metadata_2025 huggingface dataset:
85 Impact of teat order on feed consumption in swine from birth to nursery
Authors: Lichtenwalter Callan A , Apple Jason K , Kegley Elizabeth B , Tsai Tsung Cheng , Palmer Elizabeth , Knapp Joshua K , Galloway Doug
Published: July 2019

This study evaluated the relationship between teat order and its impact on feed consumption in pigs through nursery. Pigs were observed 48 h after birth to be in either a cranial, middle, or caudal teat position. Growth performance data, and active and total plasma ghrelin concentrations (determined by radioimmunoassay) were analyzed from 2 pigs in each position from 6 litters (n = 36) at 7 d of age, 21 d of age (weaning), and 62 d of age (end of the nursery stage) to determine a relationship with teat order. At weaning, pigs were moved to an off-site nursery and housed 2 pigs/pen based on teat position and litter, resulting in 6 pens/teat position. Overall, no effect of teat order was found on average daily gain (ADG; P = 0.91), average daily feed intake (ADFI; P = 0.67), gain-to-feed ratio (G:F; P = 0.33), or body weight (P = 0.94) among pigs from each teat position. A linear relationship was found between teat order and ADG (P = 0.01) as well as G:F in nursery phase-1 (P = 0.01) with caudal pigs gaining more rapidly and being more efficient than cranial pigs. Yet, in nursery phase-2, cranial pigs had the greatest ADFI (linear, P = 0.05). No difference was seen in active (P = 0.18) or total (P = 0.63) ghrelin concentrations or the active to total ghrelin ratio (P = 0.68) in relation to teat order, although there were differences in active (P = 0.04) and total (P < 0.01) ghrelin concentrations among the sampling days with the least concentrations being on d 21 for active and total ghrelin. Further study should investigate what factors would contribute to these data contradicting previous inferences about the relationship of teat order and feed consumption in pigs
96 Impact of potassium application and harvest regime in alfalfa yield, forage quality and stand persistence in South Georgia
Authors: Thinguldstad Britta , Tucker Jennifer J , Baxter Lisa , Segers Jacob R
Published: July 2019

Potassium fertilization and harvest timing can both impact stand life of alfalfa (Medicago sativa L.). In the Southeast, high temperatures and humidity often influence harvest timing and fertilization. Current nutrient management and harvest recommendations are generated from research conducted in northern climates with different varieties. The objective of this trial is to determine the impact of potassium fertilization and harvest regime on stand persistence, forage yield, and quality of ‘Bulldog 805’ alfalfa in the Southeast. This study was conducted at the Coastal Plain Experiment Station in Tifton, GA, on a two-year-old stand of ‘Bulldog 805’ alfalfa planted fall 2015. Plots were randomly assigned using a split block design. Main plots were harvest treatment: bud, and 10, 30 and 50% bloom stage. Plots were subdivided to examine K fertilization at rates: 0, 67, 101, 134 and 168 kg/ha, split 3 times throughout the season. Plots were visually assessed each harvest to determine ground cover and percent bloom. Fifty shoots were collected to evaluate leaf:stem and mass:shoot ratio, and yield was determined through harvest using a Swift forage harvester. Grab samples were collected for nutritional analysis using near-infrared reflectance spectroscopy. Data was analyzed using the PROC GLIMMIX of SAS with repeated measures analysis option at a= 0.05. Leaf:stem ratio was not significant for all main effects (P > 0.46). Harvest treatment had an effect on yield, with 10% bloom greater than bud stage (1,321 kg/ha and 1,104 kg/ha, respectively; P = 0.04). Crude protein levels were the greatest in bud stage and lowest with 50% bloom (22.8% and 21.2%; P < 0.01). Total digestible nutrients were greater in bud and 10% bloom compared to 30% and 50% (65% and 63%, respectively; P < 0.01). Potassium application and harvest regime can impact alfalfa growth. Funding for this project was provided by USDA-NIFA-AFRP grant #2016-70005-25653.
104 Administration of a DNA immunostimulant does not mitigate bovine herpesvirus-1 recrudescence in dexamethasone challenged beef cattle
Authors: Seiver Hannah A , Samuelson Kendall L , Posey Richard D , Tomczak Dexter J , Smock Taylor M , Richeson John T
Published: July 2019

The study objective was to determine the effect of a DNA immunostimulant on recrudescence of bovine herpesvirus-1 (BHV-1) after dexamethasone challenge in beef cattle. It was hypothesized that the DNA immunostimulant would mitigate stress-induced immunosuppression; thereby, reducing the incidence of BHV-1 recrudescence. Steers (n=10) and heifers (n=10; initial BW = 489 kg ± 57 kg) were stratified by pre-existing BHV-1 antibody titer, sex and initial BW and randomly assigned to treatment (n=4 pens/treatment; 2 or 3 animals/pen). All calves were administered 40 mg of dexamethasone i.v. at 0600 h from d 0 to 2, 166-d subsequent to BHV-1 challenge with 1.0 × 108 plaque-forming units per nostril. On d 1, calves were administered treatments consisting of 2 mL i.m. of DNA immunostimulant (Zelnate; ZEL) or sterile saline (CON). Once daily (0600) from d 0 to 12, a whole blood was obtained via jugular venipuncture for complete blood count (CBC) analysis and nasal swabs were collected to determine BHV-1 prevalence via virus isolation testing. A repeated measures mixed model was used to test the effect of treatment, day and their interaction for CBC variables. There was a treatment × day interaction for eosinophils (P = 0.02) and percent eosinophils (P = 0.03). Eosinophils were greater (P < 0.01) for ZEL on d 3 and 6 post-dexamethasone challenge. On d 11 and 12, eosinophils for CON rebounded such that their concentration was greater than ZEL (P < 0.01). Lymphocytes, neutrophil and monocyte concentration did not differ (P ≥ 0.44); however, a day effect (P ≤ 0.01) existed such that each variable increased transiently after dexamethasone challenge. All cattle had BHV-1 present in a nasal swab sample on at least one sample day, with prevalence of BHV-1 in nasal swab samples being greatest on d 5 (80% positive; P = 0.01). However, no treatment differences were detected for BHV-1 prevalence in this study. The DNA immunostimulant altered eosinophil concentrations but did not mitigate BHV-1 recrudesce after dexamethasone challenge
112 Effects of experimentally-induced hypoxemia on hemodynamics and blood gases, and the performance of pulse oximeters in cattle
Authors: Fontenot Lauren R , Carstens Gordon E , Lepiz Mauricio , Washburn Kevin , Hardy Joanne
Published: July 2019

Arterial oxyhemoglobin saturation (SaO2) is considered to be the reference method for evaluating lung function. There is current interest in development of biosensors to measure SpO2 (peripheral oxygen saturation) using infrared technology as a non-invasive alternative for pre-clinical respiratory detection of disease in animals. Objectives of this study were to investigate effects of experimentally-induced hypoxemia on hemodynamics (heart rate, HR and blood pressure, BP) and SaO2, and to evaluate the ability of 2 SpO2 pulse oximeters (PowerLab, AD Instruments; Passport2, Datascope) to predict SaO2 in cattle. Further, arterial lactate concentrations were measured as an indicator of oxygen delivery to tissues. Graded levels of hypoxia in seven anesthetized Holstein steers (BW = 127 ± 7 kg) were achieved by step-wise reductions in inspired oxygen fraction (FiO2) from baseline (20–35%) to target levels of 14–15%, 16–17% and 18–19%. When the desired FiO2 levels were sustained for at least 3 min, arterial blood samples (n = 56) were collected and analyzed using a co-oximeter (pHOx-Ultra, Nova Biomedical) to determine SaO2 and lactate. Simultaneously, BP, HR, and SpO2 data from the 2 pulse oximeters were recorded. Data were analyzed with a mixed model that included level of FiO2 as fixed effect. As expected, SaO2 decreased (P < 0.001) as FiO2 was reduced. Heart rate increased (P < 0.001) as FiO2 was reduced, although BP was unaffected by hypoxia. While not significantly different (P = 0.15), arterial lactate concentrations were reduced with declining FiO2. Likewise, the SpO2 values recorded by both pulse oximeters decreased (P < 0.001) incrementally as FiO2 declined, although values were only moderately correlated (P < 0.01; r = 0.35 to 0.41) with SaO2. These results demonstrate that future efforts to develop biosensors to monitor SpO2 and HR may have utility for preclinical detection of respiratory disease in livestock.
111 Changes in proinflammatory cytokines and chemokines in beef steers chronically exposed to endophyte-infected tall fescue seed
Authors: Brown Alecia R , Poole Rebecca K , Jackson McKenzie Lane , Poore Matthew H , Pickworth Carrie L , Poole Daniel H
Published: July 2019

Endophyte-infected tall fescue consumption adversely effects health and immune response. The aim of this study was to evaluate the impact of protein supplementation on cytokine response in steers consuming ergovaline, found in endophyte-infected tall fescue. Thirty-two beef steers were fed a total mixed ration (TMR) and randomly assigned to receive one of four treatments for 56 days: endophyte-free seed (0 ug/kg ergovaline) with either 18% (EF-18; n = 8) or 14% dietary protein (EF-14; n = 8) and endophyte-infected seed (500 ug/ kg ergovaline) with 18% (EI-18; n = 8) or 14% dietary protein (EI-14; n = 8). Blood samples were collected for cytokine analysis on d 28 and d 42 of the feeding period representing when steers vaccinated and boostered for bovine viral diarrhea (BVD) types 1 and 2 and infectious bovine rhinotracheitis (IBR). Cytokine concentrations were evaluated using Quantibody Bovine Cytokine Arrays. Data were analyzed using PROC MIXED of SAS with repeated measures. Statistical significance was determined at P0.05). Interestingly, concentrations of cytokines, IL13 (912±148 vs. 410.9±135 pg/mL) and IL21 (1636.0±295 vs. 629±305 pg/mL), which are involved in chronic inflammatory process were greater (P < 0.05) in EI steer compared to EF steers on d 28 and d 42. Concentrations of chemokine CCL4 and proinflammatory cytokines IFNG and IL-1alpha tended to be greater in EI steers compared to EF steers (P < 0.10). Overall, these data demonstrate that consumption of ergovaline increased proinflammatory cytokines and induced a chronic immune response. Developing a better understanding of overall immunity in cattle exposed to endophyte-infected tall fescue is fundamental to improve cattle health within the beef industry.
109 Effects of post-weaning supplementation of immunomodulatory feed ingredient on body weight and cortisol levels in programmed fed beef heifers
Authors: Danielo Jessica L , Tipton Jessie , Ricks Ralph , McCarty Keelee J , Long Nathan
Published: July 2019

The objective of this study was to determine the effects of an immunomodulatory feed ingredient during post-weaning on growth and cortisol levels of beef heifers. Commercial Angus heifers (n = 72) from two AI sires were blocked (n = 9) by sire and BW and then randomly assigned to one of two pens per block. Each pen (4 heifers/pen) per block was assigned to one of the treatments. Heifers were fed a commercial TMR twice daily from d 0 to 60 to gain 0.75 kg/day. The feed was top-dressed once a day with either 72g of Celmanax (CEL) or 72g of corn germ (CON) per pen. Body weight was collected on d -1, 0, 15, 30, 45, 60 and 61. Blood samples were collected on d 0, 15, 30, 45 and 60. Sixteen heifers (n = 8 CEL; n = 8 CON) were randomly selected for a corticotropin releasing hormone/ arginine vasopressin (CRH/AVP) challenge after the 60 d period. Two heifers per pen (n = 32) were randomly selected for a transportation challenge to evaluate stress response on d 61 or 62 of the study. Pen was the experimental unit and data was analyzed by ANOVA or repeated measures analysis as appropriate. Feed efficiency and BW gain was increased (P = 0.04) in CEL heifers compared to CON heifers. Serum cortisol concentrations were decreased (P < 0.01) in CEL heifers compared to CON heifers on d 30 to 60 post-weaning. Serum cortisol concentrations were decreased (P < 0.05) in CEL heifers compared to CON heifers during the CRH/AVP challenge from 60 to 150 minutes post infusion. Serum cortisol concentrations were decreased (P < 0.05) in CEL heifers compared to CON heifers throughout the transportation challenge. In summary, supplementation of Celmanax post-weaning increased BW gain and reduced cortisol concentrations in beef heifers.
160 Steers inoculated with Salmonella exhibit dissimilar hematology and body temperature profiles based on their exposure to a synthetic glucocorticoid
Authors: Wilkerson Shannon R , Broadway P Rand , Carroll Jeffery A , Burdick-Sanchez Nicole , Tigue Daniel A , Rehm John G , Callaway Todd R , Bratcher Christy L
Published: July 2019

The objective of this study was to determine the effects of daily dexamethasone (DEX) infusions on hematology and body temperature in response to experimental, oral inoculation with Salmonella typhimurium. Weaned Holstein steer calves (n = 20; BW=102±2.7 kg) received DEX (n = 10; 0.5mg/kg BW) or saline (CON; n = 10; 0.5mg/kg BW) for 4 d (from d -1 to d 2) while simultaneously receiving an oral inoculation of a naldixic acid resistant Salmonella typhimurium (3.4x106 CFU/animal) via milk replacer on d 0. Fecal swabs for SAL shedding were obtained daily and samples were confirmed positive starting 24 h post inoculation (d 1) to harvest (d 5). Dexamethasone (DEX) administration was achieved via indwelling jugular catheters which were fitted simultaneously with rectal temperature (RT) recording devices on d −2 relative to inoculation and placed in individual pens in an environmentally controlled facility. Whole blood was collected at -24, -12, and 0 h; and at 8-h intervals from 8 to 120 h for hematology. There was a time x treatment (There should be) for RT such that the DEX treatment resulted in a decreased RT on d -1 to 2. A treatment × time interaction (P < 0.05) was observed for total white blood cells (WBC), neutrophils, lymphocytes, eosinophils, and monocytes. Specifically, DEX increased WBC and neutrophils in DEX steers (P < 0.0001) yet lymphocytes increased following DEX administration (P < 0.05 at 24 and 48 h, respectively). Monocytes initially increased (P < 0.001) in response to the -24 h DEX treatment but slowly decreased beyond CON group levels following the 48 h DEX treatment. These data may be interpreted as either mimicking multiple acute stressors with respect to daily DEX injections, mild immunosuppression due to multiple DEX exposures, or a combination of both scenarios when juxtaposing DEX and Salmonella inoculation.
158 Long term impact of ergot alkaloids on fetal heifer development and subsequent growth and reproductive performance
Authors: Jackson McKenzie Lane , Newsome McKayla A , Brown Alecia R , Poole Rebecca K , Dudley Harrison B , Poore Matthew H , Poole Daniel H
Published: July 2019

Previous studies from our laboratory have demonstrated physiological differences in mid-gestation cows grazing either endophyte-infected (EI) or endophyte-free (EF) tall fescue. The objective of this study was to investigate the effects of in utero exposure (TRT) of either EI or EF on heifer growth, reproductive tract development and onset of puberty. Pregnant Angus and SimAngus cows were blocked by age, BW, and breed; and then randomly assigned to graze either EF (n = 27) or EI (n = 27) pastures. At parturition, heifer birthweight was recorded and placental tissues were collected to assess placental characteristics. Heifer BW, height, frame score were recorded at weaning. Assessment of puberty via measurement of BW, BCS, reproductive tract scores (RTS) and pelvic area (PA) started at 10 mo of age. Data were analyzed using a MIXED procedure of SAS and examined for effects of TRT, sire, and age. Statistical significance was determined at P < 0.05 and a tendency at 0.05); however, there was a sire by treatment interaction for ADG during onset of puberty (P < 0.05). While TRT did not affect PA or RTS (P > 0.05) at 10 mo of age, sire significantly influenced RTS (P < 0.05) thus impacting of onset of puberty. While consumption of EI fescue impacts cow performance, calf birthweight, and ratio of cotyledon to placenta weight, it has minimal effect on postnatal growth and development through 10 mo of age. Further studies are needed to determine the impact on heifer reproductive performance.
156 Effect of shipping stress on complete blood counts of backgrounded beef steers
Authors: Tigue Daniel A , Rehm John G , Wilkerson Shannon R , Holland Courteney M , Broadway Paul R , Carroll Jeffery A , Burdick-Sanchez Nicole , Theurer Miles , Rodning Soren P , Starkey Jessica D , Mullenix Mary K , Bratcher Christy L
Published: July 2019

The objective of this study was to quantify the effect of shipping to feedyards in western Kansas from the Southeast on the immune response of beef steers using complete blood counts. Angus- and Hereford-sired steers (n = 24, BW = 266.3±24.9 kg) from E.V. Smith Research Center in Shorter, AL, were weaned on June 14, 2018. The following day, blood was collected for analysis. These calves were a subset from a larger project involving grazing. As such, calves were then maintained in drylots for 14 d until grazing was available. Once grazing was initiated, these calves were placed in drylot pens with a diet consisting of dry hay with supplemented with 1% of BW of dried distiller’s grains with solubles. After 80 d, half of the calves were shipped (n = 12, SC) to Hy-Plains Feedyard, LLC. in Montezuma, KS. Immediately prior to shipment, immediately post-shipment, and after 24-hr rest, blood was collected. Blood was also collected from the unshipped calves (UC) at similar time points. Whole blood collected at each time point was analyzed for complete blood counts. The data was analyzed using the Mixed Procedure in SAS. No significant differences (P > 0.05) were detected post-weaning or pre-shipping. Immediately post-shipment, white blood cell, and neutrophil counts were greater in SC while lymphocytes counts were less (P < 0.05) than UC; however, these were not different after 24-hr rest (P > 0.05). Hematocrit and monocyte count were elevated in SC both immediately post-shipping and after 24 hr of rest (P <0.05), while reticulocyte count was lower in SC at those same time points (P < 0.05). Basophil counts were lower in SC at the 24-hr rest time point (P = 0.03). Results of this study indicate that SC did not completely rehydrate after 24 hr of rest and complete blood counts show differences in immune response due to shipping
153 Supplementing an immunomodulatory feed ingredient to modulate thermoregulation and performance in finishing beef cattle under heat stress conditions
Authors: Colombo Eduardo , Cooke Reinaldo F , Schubach Kelsey , Rett Bruna , Brandão Alice
Published: July 2019

This experiment compared body temperature and productive parameters in finishing cattle managed under heat stress conditions, and supplemented or not with a supplement based on yeast and B-complex vitamins (Omnigen-AF; OMN; Phibro Animal Health, Teaneck, NJ). Bos taurus × B. indicus cattle (64 heifers and 64 steers) were ranked by initial body weight (BW; 440 ± 3 kg) and sex, and allocated to 1 of 16 pens (8 heifers or steers/pen). Pens within sex were randomly assigned to receive (n = 8) or not (CON; n = 8) OMN at 56 g/cow daily (as-fed basis). Cattle received a total-mixed ration (d 0 to 106), and OMN was offered daily as a top-dress. Cattle were shipped on d 107 to a commercial packing facility (Friona, TX) for slaughter. Cattle BW was recorded on d 0, 14, 28, 42, 56, 70, 96, and 106. Feed intake was evaluated by measuring offer and refusals biweekly from each pen. Feed efficiency was calculated from each pen according to total feed intake and BW gain. From d 0 to 7, 28 to 42, and 84 to 98, heifer intravaginal temperature was recorded hourly (iButton temperature loggers DS1922L, Maxim Integrated, San Jose, CA). Environmental temperature humidity index (THI) was also recorded hourly throughout the experiment, and averaged 79.8 ± 0.6. Heifers receiving OMN had less (P ≤ 0.05) vaginal temperature from 1500 to 1900h across sampling days (39.05 vs. 39.19 °C, respectively; SEM = 0.04), when THI ranged from 85.3 to 90.1. However, no treatment effects were detected (P ≥ 0.20) for BW gain, feed intake, feed efficiency, and carcass traits upon slaughter (P ≥ 0.22). Collectively, results from this experiment suggest that OMN ameliorated hyperthermia in finishing cattle exposed to heat stress conditions, but such benefit was not sufficient to improve productive and carcass parameters
117 Effects of feeding a Bacillus Subtilus active microbial on the clinical health, performance and carcass characteristics of feedlot steers
Authors: Wilson Blake K , Ryan Will , DeSocio Elizabeth , Lockard Caleb , Hergenreder Jerilyn
Published: July 2019

Cross-bred steers (n = 397; initial BW = 247 ± 21 kg) from a single ranch were used to determine the effects of supplementing a Bacillus subtilus direct-fed microbial (DFM; CLOSTAT, Kemin Animal Health, Des Moines, IA) at a rate of 13 g ∙ steer−1 ∙ d−1 on feedlot performance, carcass characteristics, and clinical health during receiving and finishing. Steers were randomly assigned to pens by BW and pens were pairwise assigned 1 of 2 experimental treatments, control (CON) or DFM. Steers were housed in 12.2 x 30.5 m soil surfaced pens, and pen served as the experimental unit. There were no differences during the receiving period for overall BW (P = 0.97), ADG (P = 0.91), DMI (P = 0.77), or G: F (P = 0.79). There was a tendency (P = 0.09) for the DFM fed steers to be 14% more efficient from d 0 to 14 of the receiving period. There were also no differences in final BW (P = 0.40) or overall DMI (P = 0.46) during finishing, but there was a difference in ADG (P = 0.03) from d 29 to 56 of the finishing period where steers supplemented with DFM had greater ADG. The DFM supplemented steers also tended to be more efficient overall during finishing and for the entirety of the experiment (P = 0.07 and P = 0.08, respectively). There were no differences in carcass characteristics (P ≥ 0.31) between the experimental treatments. While limited research has been conducted examining the effects of Bacillus subtilis on feedlot performance, carcass characteristics, and the clinical health of growing and finishing steers, the results of this experiment suggest that the supplementation of a strain Bacillus subtilis at a rate of 13 g ∙ steer−1 ∙ d−1 may improve feed efficiency
167 Livestock Literacy: Ensiling newspaper as a renewable fiber source for ruminant animals
Authors: Finn Natalie A , Cherry Nichole M , Muir James P , Smith William B
Published: July 2019

Per unit energy, fiber is among the most expensive components of the ruminant diet. While the use of by- or co-products can help offset the costs of feeding cattle, these feeds often increase in price with increased adoption. Wastes from human enterprises may represent the next step in feedstuff investigation. Our objective was to evaluate the suitability of newspaper as a component of silage for ruminant feeding. Newspapers were obtained from the Dick Smith Library and JTAC News at Tarleton State University (Stephenville, TX). Samples were cut into strips (approximately 4.0 × 30.2 mm) using an office shredder. Sorghum-sudangrass [Sorghum bicolor (L.) Moench ssp. drummondii (Nees ex Steud.) de Wet & Harlan] was harvested and cut by hand to lengths of approximately 10 cm. Samples were combined to achieved DM ratios of 100:0, 75:25, 50:50, 25:75, and 0:100% newspaper and sorghum-sudangrass. Distilled water was added to achieve 45% DM. Samples were packed in a double layer of plastic sheeting and sealed in 19 L buckets. Laboratory silos were arranged in a Latin square design in a laboratory and allowed to ferment for 35 d. Ensiled samples were assayed for DM, particle size, and silage acids. There was no effect of newspaper percentage (P = 0.47) on silage pH. Ammonia (0.04 to 1.2% DM), total VFA (0.01 to 4.8% DM), lactic acid (0 to 46.6% VFA), and acetic acid (0.01 to 2.4% DM) increased linearly (P < 0.01) with increased concentration of sorghum-sudangrass. Results indicated that newspaper alone was not an effective feedstuff to ensile. However, addition of newspaper to grass silages could represent a viable means to decrease cost and extend resources for ruminant animal producers.
161 Evaluation of cull sweet potato storage roots as a winter supplement to grazing for cow-calf pairs
Authors: Parish Jane A , Rutherford Cobie , Meyers Stephen L , Shankle Mark W
Published: July 2019

Cull sweet potato storage roots that would otherwise be left unharvested in production fields or dumped as waste from excess supplies in storage may be available for use as livestock feed at competitive pricing relative to other feedstuffs. Given this potential economical source of nutrients for consumption by beef cattle, the objective of this study was to assess cow-calf performance using unprocessed sweetpotato storage roots as a winter supplement to grazing cow-calf pairs as compared to whole cottonseed or no supplement. Fall-calving multiparous Bos taurus crossbred cows in Prairie, MS, were allotted ad libitum access to mixed-grass pasture with tall fescue as the predominant forage species and randomly allocated to one of three as-fed basis supplement groups: 6.8 kg/cow/d of sweetpotato storage roots (SWP); 2.3 kg/ cow/d of whole cottonseed (WCS); or no supplement (NONE). Supplements were offered to cows on a group basis on every Monday, Wednesday, and Friday for 93 d each winter initiating December 5, 2016 (n = 81) and December 11, 2017 (n = 105). Cow BCS on a scale of 1 to 9 (1 = emaciated; 9 = obese) at supplementation initiation was 6.1 ± 0.1. From supplementation initiation until calf weaning in March, change in cow BCS (P < 0.01) was greatest for NONE (-1.1 ± 0.1), intermediate for SWP (-0.7 ± 0.1), and least for WCS (-0.4 ± 0.1). Adjusted 205-d calf BW was 16.9 ± 3.8 kg heavier (P < 0.01) in steers than heifers but did not differ (P = 0.41) among supplementation groups. Although nursing calf performance was not impacted by supplementation regime, results suggest that cull sweetpotato storage roots may be an effective feedstuff for winter supplementation intended to reduce BCS loss in lactating beef cows. Additional research to determine optimal frequency and quantity of SWP supplementation is warranted
164 Effects of year-round supplementation of sugarcane molasses/urea or range cubes on growth performance of Bos indicus-influenced beef cows and their offspring
Authors: Palmer Elizabeth , Vedovatto Marcelo , Ranches Juliana , Gouvêa Vinícius , Miranda Miguel , Arthington John , Vendramini João , Moriel Philipe
Published: July 2019

This study compared the effectiveness of liquid sugarcane molasses/urea or wheat middlings-based range cubes supplementation on performance of beef cow-calf pairs. On d 0, 82 mature pregnant Brangus cows were stratified by BW and BCS (433 ± 47 kg; BCS = 4.6 ± 0.77) and randomly allocated into 1 of 6 bahiagrass pastures (13–14 pairs and 9.3 ha/pasture). Treatments were assigned randomly to pastures (2 pastures/treatment) and consisted of cows offered: winter supplementation of molasses/urea from calving until end of breeding season (d 161 to 300; MOL-W), or year-round supplementation of liquid urea/molasses (MOL-Y) or range cubes (CUB-Y). Supplement amount offered to cows differed monthly among treatments, but all cows were limit-fed 272 kg/yr of the respective supplement DM and similar trace mineral supplementation (336 g/cow/wk). Cubes were formulated to be isocaloric and isonitrogenous compared with molasses/urea (75% TDN, 20% CP; DM basis). Weekly supplement amount was divided in half and offered every Monday and Thursday. Cow BCS: did not differ among treatments from d 0 to 74 (P ≥ 0.56); was greater at calving (d 161) for MOL-Y and CUB-Y vs. MOL-W cows (P ≤ 0.05); and was greatest, intermediate, and least at start of breeding season (d 217) for MOL-Y, CUB-Y, and MOL-W cows (P ≤ 0.05), respectively. Liver concentrations for Co, Se, and Cu on d 122 and 217 were greater (P ≤ 0.02) for CUB-Y vs. MOL-W and MOL-Y cows. Calving date, percentage of pregnant cows on d 360, and calf birth BW, pre-weaning ADG, and BW at weaning did not differ (P ≥ 0.14) among treatments. Therefore, year-round supplementation of liquid molasses/urea and range cubes enhanced cow BCS at calving and start of breeding season but did not impact subsequent reproductive performance of cows and calf weaning weights than conventional winter molasses/urea supplementation of cows
163 Effects of pre- and post-partum supplementation of molasses/urea with or without methionine fortification on growth performance of primiparous cows and their offspring
Authors: Vedovatto Marcelo , Palmer Elizabeth , Ranches Juliana , Miranda Miguel , Gouvêa Vinícius , Arthington John , Vendramini João , Moriel Philipe
Published: July 2019

The present study evaluated the performance of calves born from primiparous cows offered pre- and post-partum supplementation of sugarcane molasses/urea added or not with DL-methionine hydroxyl analog. On d 0 (~56 d before calving), 36 Brangus heifers were stratified by BW and BCS (345 ± 4.7 kg; 2 yr of age), and randomly allocated into 1 of 12 bahiagrass pastures (3 heifers and 1.2 ha/pasture). Treatments were randomly assigned to pastures (4 pastures/ treatment) and consisted of no supplementation (NOSUP) or supplementation of molasses/urea (7.2 kg DM/heifer/ wk; 75% TDN, 20% CP; DM basis) with (MOL+) or without (MOL-) fortification with 105 g/heifer/wk of methionine (Alimet, Novus International Inc., Romance, AR) from d 0 until all heifers within each pasture calved. Total weekly amount of molasses/urea (and methionine for MOL+ heifers) was divided by 2 and offered on Tuesdays and Wednesdays. After all cows calved, all pairs were fed 12.7 kg/cow/wk of molasses/urea (DM basis) and grazed a single bahiagrass pasture until calf early-weaning (d 147). Calves received a soybean hull-based supplement at 3.5% of BW (DM basis) and ad libitum stargrass hay from d 154 to 201. Calving date and cow BCS on d 44 did not differ between MOL+ and MOL- (P ≥ 0.50), but both groups calved at greater BCS than NOSUP cows (P ≤ 0.008). However, cow BCS on d 147 and pregnancy percentage on d 288 did not differ among treatments (P ≥ 0.27). Calf birth BW did not differ among treatments (P ≥ 0.21), but ADG from birth to d 201 was greater for MOL+ and MOL- vs. NOSUP calves (P ≤ 0.05). Therefore, pre- and post-partum supplementation of sugarcane molasses/urea improved cow BCS at calving and calf postnatal growth compared with no supplementation. Supplemental methionine did not further enhance cow and calf growth performance
173 The effects of Fescue EMTTM Mineral Defense on stocker heifer growth while grazing tall fescue
Authors: Taylor Anna R , Dew Randy , Bryan Ken , Pike J Nathan , Lock T Ryan
Published: July 2019

Previous research demonstrates grazing tall fescue can decrease reproductive performance and weight gain in cattle. The objective of this study was to evaluate Fescue EMTTM Mineral Defense (Cargill Animal Nutrition, Minneapolis, MN) on summer weight gain in cattle grazing tall fescue pastures in SW Missouri. Heifers (n = 120; initial BW = 236 ± 2.5 kg) were stratified by weight to replicated tall fescue pastures to either a control mineral treatment or Fescue EMT™ Mineral Defense treatment. Forage availability was estimated weekly by ultrasonic sensor. Pasture samples were collected every 21 d and analyzed for ergovaline concentrations. Heifer weights and blood prolactin were measured throughout the trial. Average daily mineral consumption was calculated by mineral offered less residual. Data were analyzed on a pen-mean basis as a completely randomized design using JMP with 6 pens/ treatment and 10 heifers/pen. Prolactin was analyzed as Repeated Measures in JMP. Initial weights between treatments were not different (P > 0.05). Endophyte infection measured 75% or greater in all pastures. No differences were detected in pasture ergovaline (149 ± 19 µg/kg) or pasture availability (2,600 ± 150 kg/ha) between treatments (P > 0.20 at each sampling). Heifer ADG consuming Fescue EMT™ Mineral Defense compared to control mineral was greater at 0.28 kg versus 0.22 kg resulting in total gains of 21.8 kg versus 16.6 kg, respectively (P < 0.05). However, blood prolactin numerically decreased over time in both treatments. Results from this trial demonstrate a 31% improvement in weight gain for cattle consuming Fescue EMTTM Mineral Defense compared with cattle consuming a control mineral while grazing toxic tall fescue.
178 The Effect of Fleshing Ability on Cow and Calf Performance
Authors: Holder Amanda , Wiseman Aksel , McGee Adam , Lalman David , Andresen Claire
Published: July 2019

Several factors influence the overall maintenance requirements of a mature beef cow including age, gain, lactation, pregnancy, and fleshing ability. However, limited research is available to distinguish what sets a hard-fleshing cow apart from an easy-fleshing cow. Cows that are hard-fleshing maintain a lower body condition score (BCS) throughout the year compared to easy-fleshing counterparts. The objectives of this experiment are to determine the differences in characteristics and production between cows classified as easy- vs. hard- fleshing. Characteristics of interest include feed intake, milk yield, milk composition, body weight changes, BCS changes, and other body composition measurements, as well as calf weaning weight. In this study, 24 spring-calving, mature Angus beef cows were classified as either hard-fleshing or easy-fleshing based on BCS and ultrasound measurements for back fat and rump fat. The intake study took place during the second trimester, cows were assigned to an easy- or hard-fleshing pen based on treatment where they remained for the entirety of the 45-day intake study. Each treatment was replicated three times in a completely randomized design. Milk data collection began one month after calving with monthly milkings from May—August. There were no differences (P = 0.9) in DMI, although hard-fleshing cows had greater DMI calculated on a metabolic body weight basis (P = 0.05). There was a trend (P = 0.12) for hard-fleshing cows to wean heavier calves, although there was no difference in mean milk yield (P = 0.44). Body condition score was positively correlated with protein and carbohydrate content of milk with easy-fleshing cows having greater contents of both (P = 0.02 and P < 0.01, respectively). Overall, an increase in BCS without an increase in DMI may be beneficial from a reproductive standpoint, though more research in this area is needed.
179 The effect of competition for an automated supplement feeder on supplement intake behavior of stocker steers
Authors: Husz Taylor C , Goad Carla , Reuter Ryan
Published: July 2019

Interest in automated, precision feeding equipment is increasing, and users need information about how to effectively use this new approach. Our objective was to determine the effect of competition for a feeding space at an automated supplement feeder on supplement intake behavior. Mixed breed beef steers (n = 128, initial BW = 257 ± 29.2 kg) were randomly assigned to 8 paddocks. One paddock (16 steers) was selected to have continuous access to the feeder for the duration of the 16-wk trial; this paddock was designated the “tester” paddock. The automated feeder consisted of a large bin that dispensed supplement into 4 feeding stations. Supplement dispense was triggered by the presence of an eligible animal’s RFID tag; each steer was limited to 0.50 kg supplement/d by the electronics of the feeder. Weekly, additional paddocks were commingled with the tester paddock to increase competition for the feeder, resulting in a stocking density from 4 to 32 steers per feeding station in various weeks. Approximately 30% of the steers did not voluntarily use the feeder; therefore effective competition was less than the study design. Supplement intake and GPS location were recorded for steers in the tester paddock, and averaged for each wk; week was the experimental unit (n = 16). Weekly mean supplement intake and time spent near the feeder were regressed on feeder stocking density. Tester steers consumed an average of 0.36 kg supplement/d. Competition for a feeder space numerically reduced (P = 0.15) supplement intake by 0.002 kg/d per steer of competition. Steers spent 6% of the time within 15 m of the feeder regardless of competition (P = 0.82). This data illustrates that in scenarios similar to these experimental conditions, the feeder can be stocked with at least 80 animals with minimal effects on supplement intake.
177 The effect of breeding system on voluntary forage consumption of beef cows
Authors: Andresen Claire , Holder Amanda , Gross Megan , Wiseman Aksel , McGee Adam , Lalman David
Published: July 2019

Recent genetic trends in beef breeds suggest an imbalance in the selection of output and input traits. The inverse relationship between cow maintenance requirements with output traits such as growth and milk production may have ramifications on carrying costs of cows as well as feed intake of the cow herd. One method commonly used to maximize efficiency within a production system is to utilize a crossbreeding system to capitalize on breed complementarity. The objective of this study was to investigate the impact of breeding system on forage intake and determine correlations between breeding system, dry matter intake, and maintenance requirements of beef cows. To do this, a 45-d feeding trial was conducted using 59 pregnant, non-lactating Angus (ANG; n = 32) and Hereford x Angus (HA; n = 27) cows similar in mature BW, growth, and milk potential. Animals were assigned to pen based on breed with four pen replicates per breed. Cows were housed in dry-lot pens equipped with shade, windbreaks, and feed bunks with free-choice access to clean water. A chopped hay ration (65% DM, 55.7% TDN, 7.8% CP) was provided ad libitum to determine forage intake. Daily intake tended to be lower (P = 0.06) for HA compared to ANG (134.25 g/kg MBW ANG; 125.37 g/kg MBW HA). There was no difference in BW at initiation or conclusion of the trial, however, HA sustained greater BCS throughout the duration of the study (P > 0.01). After accounting for differences in retained energy, there were no detectable differences in maintenance requirements (P = 0.11). Results of this study suggest lower forage intake of crossbred cattle and suggests potential differences in energy prioritization and partitioning between breeds.
190 Reduce Reuse ReRumen: Preservation method of rumen fluid collected from slaughtered cattle affects in vitro digestibility
Authors: Garcia Taylor J , Brady Jeffrey A , Guay Kimberly A , Muir James P , Smith William B
Published: July 2019

Microbes and chemical constituents in the rumen fluid play an important role when re-establishing the rumen microbial population. Identification of a viable preservation method could have lasting implication of veterinary and research applications. Our objective was to determine the efficacy of preservation methods on rumen liquor. Twelve paunch samples were collected from slaughtered cattle at the Tarleton State University Meat Laboratory, Stephenville, TX. Rumen content was collected from different locations within the rumen, strained through eight layers of cheesecloth, and divided into five 500-mL aliquots. Aliquots were randomly allocated to one of five preservation methods (freezing or lyophilisation) and preservative (glycerol; yes or no). A fresh control was maintained from each sample. Three reference feeds and two roughage sources were used in the batch culture procedure. Reference feeds were dried to a constant weight at 55°C and ground to pass through a 2-mm screen. Ground samples were subjected to batch culture in vitro true digestibility (IVTD) assays using each of the four ruminal fluids (plus the control) for digestibility estimates. Original samples and incubated residues were assayed for DM, CP, NDF, and ADF. Data were analyzed in a 2 × 2 + 1 augmented factorial design using GLIMMIX procedure of SAS. There were no differences (P > 0.05) in IVTD when using protein or energy feeds; however, there were differences in IVTD for all treatments for fiber concentrates and forage reference feeds. Despite lower degradation of feeds when frozen or lyophilized rumen fluid was used, preserved rumen fluid may be a viable option in the absence of fresh inoculum for veterinary and research applications
131 Milk yield of ewes fed with diets of different energy levels
Authors: Gallo Sarita Bonagurio , Junior Vanderlei Benetel , Santos Fernanda Ferreira dos , de Oliveira Mariluce Cardoso , Tedeschi Luis Orlindo
Published: July 2019

An adequate sheep milk production ensures survival and optimum lamb’s growth and development through the weaning. To evaluate the effects of different energy sources in the diet of ewes on their milk yield, an experiment was carried out at the Faculty of Animal Science and Food Engineering of USP, Brazil, using 56 pregnant ewes, Dorper and Santa Ines breeds, average live weight of 70 kg, randomly distributed in four treatments: control group (fed according to the 2007 NRC recommendation); and groups with 10% more energy with different sources (starch, ST; protected fat, PF; and chromium, Cr). Dry matter intake was approximately 3% of the live weight of the ewes, to all treatments, but the control group with intake of 2.1 Mcal EM/d and the other with 2.3 Mcal EM/d. Ewes were fed the experimental diets at the beginning (50 d) and end of the gestation (50 d). In the middle of the gestation (50 d) the sheep were fed according to the recommendation of the NRC (2007). At 20, 30, 40, 50, and 60 days post-lambing, the milk yield was assessed using an indirect method of double weighing the lambs (one weight before suckling, another weight after suckling). The ewe milk yield was analyzed using contrasts and statistical significance at 5% of probability. There was no statistical difference (P > 0.05) among the diets evaluated on milk yield of the ewe (0.42, 0.45, 0.38, 0.3, and 0.14 kg/d for 20, 30, 40, 50, and 60 days of lactation). We concluded that milk yield of ewes receiving different levels and source of dietary energy did not differ. Additionally, the use of Cr or protected fat did not influence milk yield when added at 10% of the required energy for lactation. Acknowledgment to FAPESP (process 2017/20555–8).
202 In vitro digestibility of various browse species selected by goats over the growing season
Authors: Ryan Nikisha , Abrahamsen Frank W , Epps Briana , Mullenix Mary K , Heath John , Smith Ron , Gurung Nar
Published: July 2019

Goats naturally prefer to consume browse species given the choice. Browsing away from the ground may help avoid internal parasites; however, goats cannot consume more than 50% of their diet as browse due to the prevalence of toxins in the browse species. The objective of this project was to determine in vitro true digestibility (IVTD) of preferred browse species consumed by goats at Tuskegee University browsing demonstration site over the growing season. Three samples were collected from each of the 35 different browse species in April and July 2018. Samples consisted of leaves and edible twigs. Browse IVTD was determined according to the Van Soest et al. (1991) modification of the Tilley and Terry (1963) procedure using the Ankom Daisy II incubator system. Data were analyzed for the months of April and July utilizing the two-sample T-test of SYSTAT, Version 13. Browse IVTD values differed (Pteridium aquilinum (Brakenfern) to 94.7% in Phytolacca americana (pokeweed) while the July values ranged from 33.59% in Pteridium aquilinum to 88.5% for Morus rubra (Mulberry). Significant differences were also observed among browse species with regards to dry matter content. Dry matter content values ranged from 10.5 (Albizia julibrissin; White mimosa) to 81% (Prunus americana; American Plum) in April and 12.5 Phytolacca americana to 89% Pinus taeda (Loblolly Pine) in July. Results showed natural variability in IVTD of various browse species throughout the growing season. Future experiments will analyze additional nutritive value parameters such as ADF, NDF, total digestible nutrients, and lignin values over three collection times (April, July, and October). The experiment will be continued for two additional years to provide meaningful results.
2 Biosensors - New Frontiers in Animal Welfare
Authors: Neethirajan Suresh
Published: July 2019

Glocalization and ecological pressures increase the risk of a biological incident of national significance in farmed animal health management, such as the emergence of a novel infectious agent and/or a global pandemic. An important strategy to monitor such an incident is to anticipate when and where it may occur to enable a timely and well-informed measurement as response. As agreed by researchers, industry experts and market watchers, the fourth revolution in agriculture has begun. Novel technologies such as Internet of Things, SMART Agriculture Initiative, Precision Agriculture, and development of apps for disease surveillance are emerging to drive efficiency. As such, rapid on-farm diagnostics of novel infectious agents and global pandemics using advanced diagnostic methods and tools, as Smart (Precision) Farming and Agricultural IoT (Internet of Things), is significant as part of the fourth agricultural revolution. This talk will discuss examples of innovations such as arrays of diagnostic platforms and wearables as nanosensors using biotechnology to detect 1) biomarker proteins; and 2) antibodies targeting specifically the proteins in multiple livestock sectors: dairy animals; poultry; and pork sectors to diagnose diseases and infections. With novel infectious agents and global pandemics on the rise in farmed livestock, it is imperative to develop detection tools that can predict when an incident is likely to occur, determine the exposed population, inform diagnosis and treatment decisions, and forecast the incident’s potential impact on human and animal populations. The amount of time farmers will have to spend on the farm to make decisions will be significantly reduced. With automated and rapid disease monitoring, farmers will be able to receive real-time information on their livestock, increasing both the efficiency and sustainability for farming and livestock production.