bluuebunny/crossref_metadata_2025 huggingface dataset:
2 Acute phase response to lipopolysaccharide challenge in beef steers supplemented with prebiotic blends
Authors: Sanchez Nicole C Burdick , Broadway Paul R , Carroll Jeffery A , Compart Devan M Paulus , Forcherio J C
Published: November 2020

A study was conducted to determine the effects of two prebiotic blends on the acute phase response (APR) following lipopolysaccharide (LPS) challenge in steers. Crossbred steers (n = 36; 273±4 kg) were fed for 21d on three different treatments: 1) Control, fed a standard receiving ration; 2) Control ration supplemented with a Prebiotic/Probiotic blend (28.4 g/hd/d; PMI); and 3) Control ration supplemented with a DFM/Prebiotic blend (19.0 g/hd/d; PMI). On d20, calves were fitted with indwelling rectal temperature (RT) monitors and jugular catheters and moved into individual stanchions in a covered barn. On d21, blood samples were collected, and sickness behavior scores recorded at 0.5-h intervals from -2 to 8h and again at 24h relative to an i.v. challenge with 0.25 µg/kg BW LPS. Serum was isolated and stored until analyzed for pro-inflammatory cytokines, cortisol and glucose concentrations. Complete blood counts were measured every 2h from -2 to 8h and again at 24h. Pre-challenge RT measured for 18h prior to the challenge tended (P = 0.10) to be affected by treatment such that calves fed the Prebiotic/Probiotic blend had greater RT than Control and tended to be greater than calves fed the DFM/Prebiotic blend (38.9, 39.2, and 39.0±0.1oC, respectively). Post-challenge RT increased 0.8–1.0oC on average but did not differ between treatments (P = 0.53). Sickness behavior scores were not different between treatments (P = 0.14). There were no differences in white blood cell or differential counts between treatments (P ≥ 0.25). Serum concentrations of TNF-α, IL-6, and IFN-γ increased in response to the challenge (P < 0.01) but were not different between treatments (P ≥ 0.26). Serum cortisol and glucose concentrations were reduced in both supplemented groups compared to Control steers (P ≤ 0.006). Therefore, the data suggest that the effects of the prebiotic blends during an immune challenge were limited to alterations in metabolic biomarkers and energy utilization.
182 Uterine gene expression of beef cows in response to supplementation with calcium salts of soybean oil
Authors: Timlin Claire L , Parrish Taylor , Dias Nicholas W , Santili Felipe , Pancini Stefania , Mercadante Vitor R G
Published: November 2020

We hypothesize that expression of peroxisome proliferator-activated receptors (PPARs; PPARa, PPARg, PPARd) and prostaglandin synthases (PGES, AK1B1) in endometrial tissue of Bos taurus beef cows changes after supplementation with calcium salts of soybean oil (CSSO) rich in omega-6 fatty acids compared to a saturated fat. Multiparous cows, stratified by BW (658.05±16.64 kg) and BCS (7.52±0.18), were randomly assigned to one of two treatments: 1) 0.7 kg/(hd.d-1) corn gluten feed + 0.1 kg/(hd.d-1) of prilled saturated fatty acids (Energy Booster, Milk Specialties, Eden Prairie, MN; CON, n = 12); or 2) 0.7 kg/(hd.d-1) corn gluten feed + 0.1 kg/(hd.d-1) of CSSO (Essentiom, Church and Dwight Co., Inc., Princeton, NJ; CSSO, n = 13). Cows were given a 21-d adaptation period before initiation of the experiment, maintained on common pasture, provided ad libitum access to forage and water, and individually fed treatments. Cows underwent a 7-d CO-Sync+CIDR estrus synchronization protocol beginning d0. Transrectal ultrasonography was performed d14 to determine location of a corpus luteum (CL). Uterine biopsies were collected d18 and d28 of the study, corresponding to d8 and d18 of the estrous cycle, respectively. One biopsy was taken from the anterior-most portion of uterine horns ipsilateral and contralateral to the CL for RNA extraction. Transcript expression was analyzed with reverse transcriptase qPCR and quantified using the 2-ddCt method with GAPDH as reference gene. There was no treatment effect for any transcripts analyzed (P ≥ 0.30), nor an interaction between treatment, horn relative to CL, and day (P ≥ 0.11). Transcript expression increased for both treatments from d18 to d28 for PPARa (0.8±0.18 vs. 1.8±0.22, P = 0.01), PPARd (1.13±0.12 vs. 1.9±0.13, P < 0.01), PPARg (1±0.2 vs. 1.3±0.25, P = 0.01), and AK1B1 (0.62±0.16 vs. 2.34±0.22, P < 0.01). While uterine transcript expression of selected genes increased through the luteal phase, supplementing beef cows with CSSO did not affect transcript expression compared to cows receiving saturated fat.
140 Relaxin Regulates Porcine Adipose Tissue Development by Inhibiting Preadipocyte Number, Stimulating Lipolysis, and Upregulating mRNA Expression of Adipokine, Fatty Acid Metabolism and Extracellular Matrix Genes
Authors: Charlton Courtney E , Reeves Maegan A , Brandebourg Terry D
Published: November 2020

Relaxin (RLN) is best known as a reproductive hormone that remodels cervical connective tissue. However, porcine adipose tissue can secrete and respond to RLN, suggesting locally derived RLN could modulate adipose tissue development and function. To test this hypothesis, primary cultures of porcine subcutaneous adipose tissue stromal-vascular (AT-SV) cells and visceral adipose tissue explants were utilized as model systems to determine the effect of 100 ng/ml exogenous RLN on 1) preadipocyte proliferation and differentiation, 2) the mRNA expression of adipokine, extracellular matrix protein and fatty acid metabolism genes, and 3) lipolytic rate in porcine adipose tissue. AT-SV cells were harvested from 3-day-old neonatal pigs (n=6) and plated in vitro in growth medium containing either vehicle or RLN for cell number assays or were induced to differentiate by treatment with insulin, hydrocortisone, and rosiglitazone for 8 days in the presence or absence of RLN for adipogenesis assays. Total RNA was extracted from differentiating cultures on days 0 and 8 post-induction. Real-time PCR was then utilized to determine changes in mRNA expression for target genes. For lipolysis and cell signaling experiments, visceral adipose tissue was obtained from market weight pigs at harvest, minced into explants, and cultured in serum-free medium in the presence or absence of RLN and cAMP pathway modulators with differences in glycerol release determined following 2-hour treatment. Overall, RLN decreased preadipocyte number 1.27-fold under serum-free conditions (P < 0.05), enhanced adipogenesis based upon 2.4-fold increase in GAPDH activity (P < 0.05) and a 2.2-fold increase in ORO accumulation (P < 0.05) while significantly increasing the mRNA expression of multiple metabolic, adipokine, and extracellular matrix component genes. RLN treatment stimulated glycerol release by 3-fold via the cAMP pathway (P < 0.01). Collectively, these data support the hypothesis that RLN regulates adipose tissue development through stimulating adipogenesis and modulating adipocyte metabolism.
133 Provision of Artificial Shade During Summer Reduced Vaginal Temperature and Improved Growth Performance of Pregnant Grazing Beef Heifers
Authors: da Silva Gleise Medeiros , Laporta Jimena , Dubeux Jose Carlos Batista , Chebel Ricardo , DiLorenzo Nicolas
Published: November 2020

This study evaluated the effects of providing artificial shade during the summer in Florida on growth performance and vaginal temperature (VT) of pregnant grazing beef heifers. From July to September 2017 (THI from 61.5 to 92.3), 36 black-hided Angus and Angus crossbred pregnant heifers (418 ± 20 kg BW) were stratified by breed, blocked by body weight (BW) and allocated to 12 bahiagrass pastures (Paspalum notatum Flüggé; 1.3 ha, n = 3 heifers/pasture), with (SHADE; 6 pastures) or without (NO SHADE; 6 pastures) access to artificial shade. The shade structures were comprised of a shade cloth that measured 11 × 7.3 m in length and provided 26.8 m2 of shade per animal. Shrunk and full BW were obtained on d 0 and 47, and on d 14 and 28, respectively, to assess changes in BW and average daily gain (ADG). Vaginal temperature was automatically recorded every 10 min for 5 d during weeks 1, 3, 5, and 7 of the study using an intravaginal digital thermo-loggers attached to a blank CIDR. Herbage mass was measured every 14 d to calculate herbage allowance (HA), and additional heifers were used as needed to maintain the same HA among pastures. No differences were observed for HA (P = 0.78). The ADG from d 0 to 47 (P = 0.08 and SEM = 0.07) tended to be greater for SHADE relative to NO SHADE heifers (0.20 vs. -0.02 kg, respectively), whereas no differences were observed for BW (P > 0.10) throughout the study. Vaginal temperature was reduced for SHADE vs. NO SHADE heifers on weeks 1 and 3 (P < 0.001); however, no differences were observed on weeks 5 and 7 (P > 0.10). Providing artificial shade during summer to pregnant grazing beef heifers reduced vaginal temperature and tended to improve ADG.
107 Influence of chronic melatonin supplementation on bovine testis physiology
Authors: Littlejohn Brittni P , Mercer Kayla B , Bowers Karrigan J , Messman Riley D , Contreras-Correa Zully , Reid Dana , Feugang Jean , Vann Rhonda C , Lemley Caleb O
Published: November 2020

The objective was to evaluate the influence of melatonin supplementation on bovine testis biometrics, thermoregulation, and blood flow in two age groups. Mature and peri-pubertal bulls received four subdermal 24 mg melatonin implants (MEL; n = 5 and n = 6, respectively) or no implants (CON; n = 5 and n = 6, respectively) every 30 ± 4 d for 120 ± 5 d. Body weight, scrotal circumference (SC), testes temperature (average temperature of left and right testes as quantified with thermal imaging), and total testicular artery blood flow (TBF; total blood flow to left and right testes as measured with Doppler ultrasonography) were evaluated on d 60, 90, and 120 ± 4. On d 120, peri-pubertal bulls were castrated and total testes weight (TTW) determined. Data were analyzed using MIXED procedures of SAS specific for repeated measures with treatment, time, and the interaction as fixed effects and sire (peri-pubertal only) as a random effect. On d 120, peri-pubertal bull data were analyzed using MIXED procedures of SAS with treatment as a fixed effect and sire as a random effect, and relationships of TBF, SC, TTW, testes temperature, and ambient temperature assessed using CORR procedures of SAS. Body weight, testes temperature, TBF, and TBF as a proportion of SC changed over time in peri-pubertal (P < 0.05) but not mature (P > 0.05) bulls. On d 120, TBF was increased (P = 0.05) and TBF as a proportion of TTW tended (P = 0.10) to be increased in MEL (95.48 ± 14.63 mL/min and 0.29 ± 0.03 mL/min*g, respectively) compared to CON (65.06 ± 15.10 mL/min and 0.21 ± 0.03 mL/min*g, respectively) peri-pubertal bulls. TBF was positively correlated with SC (r = 0.59; P = 0.04) and TTW (r = 0.66; P = 0.02). Ambient temperature was positively correlated with testes temperature (r = 0.78; P < 0.01). No other differences were identified (P > 0.05). Limited alterations in testis physiology were observed in melatonin-supplemented bulls.
138 Randel Lecture: Reproductive Behavior – the basis of reproductive success
Authors: Alexander Brenda M
Published: November 2020

In domesticated, promiscuous species like sheep, mate choice is constrained by breeding strategies with limited mate choice. The proportion of rams with limited sexual interest in ewes is nearly 30% of the total number of breeding rams. Rams with low sexual interest detect putative sexual signals from ewes but fail to act in a suitable manner. While a tempered reward mechanism with decreased dopamine synthesis in the mid-brain of low sexually performing rams may partially account for this behavior, how the ewe responds to low-sexually performing rams remained unknown. Ewes are relatively undemonstrative in the expression of sexual behavior. The most widely expressed behavior from the ewe is the increased ambulatory behavior to seek out and affiliation with a ram. The expression of this behavior is estrogen dependent and likely increases the sexual interest of the ram and the reproductive success of the ewe. Rams with low sexual interest do mate and sire lambs. It might be expected that ewe affiliation behavior would increase when the ratio of ewes to rams is high (ie. breeding intensity) or sexual interest is low. This does not appear to be the case since ewes express more proceptive behavior toward rams with greater sexual interest. Ewes spent more time in affiliation with high sexually performing rams (P < 0.001) 57.7% (±3.3) than those expressing low sexual interest (23.8% [± 3.4]). Rams expressing high sexually interest garner more solicitous looks from ewes than do low performing rams. Time in affiliation highly correlated with expression of ram behaviors including number of mounts, total anticipatory, and consummatory behavior. While ewes exhibited increased number of purposeful moves toward high performing rams, movement away from the ram to did not differ by expression of male behavior. In conclusion, ewe behavior does not compensate for low sexual interest from the ram and would not be expected to contribute to the reproductive success of rams expressing low sexual interest.
37 Early pregnancy detection in cattle by analysis of maternal circulating microRNA expression
Authors: DeCarlo Andrea N , Parrish Joseph , Long Nathan , Pratt Scott
Published: November 2020

Pregnancy detection in cattle is performed by rectal palpation, transrectal ultrasonography or detection of pregnancy associated glycoproteins at approximately d 28 of gestation. Majority of embryonic loss in cattle occurs much earlier. MicroRNAs (miRNAs) are excellent markers for physiological states including pregnancy. The objective of this experiment was to assess expression of miRNAs in maternal serum to serve as markers for pregnancy detection at d 18 post-artificial insemination. Cows of varying age and parity (n = 80) were synchronized using a 7-d Co Synch and CIDR estrous synchronization protocol. One insemination by a single sire was performed 60 to 66 h following CIDR removal. Blood was collected via jugular venipuncture on d 0 and 18 post-insemination. Total RNA isolation was performed using PAXgene Blood RNA kit (PreAnalytiX, Hombrechtikon, Switzerland) or by miRNeasy (Qiagen, Hilden, Germany). Ultrasound was performed d 30 of gestation. Taqman microRNA assay utilizing primers for Let7a, mir-16,15b, 25, and 26 was performed on RNA from whole blood and serum in pregnant (n = 10) and open (n = 10) cows. Analysis of variance and pair-wise student’s t-test among LSMeans for relative abundance were performed with fixed effects for pregnancy, day, isolation, and their interactions. MicroRNA abundance did not differ due to pregnancy. Relative abundance for miR-16 increased in d 18 (1.86 ± 0.49) compared to d 0 samples (3.42 ± 0.48), regardless of pregnancy status or isolation method (P = 0.03). Let-7a (serum, 0.99 ± 0.98; PAXgene, 6.25 ± 0.87), miR-15b (serum, 0.59 ± 1.67; PAXgene, 12.44 ± 1.48) and miR-26 (serum, 1.44 ± 1.2; PAXgene, 7.64 ± 1.06) relative abundance was higher in serum compared to PAXgene isolated samples (P < 0.05). These results disagree with previous reports and indicate that these candidate miRNAs are not a reliable indicator for early pregnancy detection in cattle.
42 Effect of injectable trace mineral supplementation on beef cows fertility and overall mineral status
Authors: Pancini Stefania , Currin Jhon F , Stewart Jamie L , Clark Sherrie , Redifer Tracey , Dias Nicholas W , Timlin Claire L , Sales Alvaro , Mercadante Vitor R G
Published: November 2020

The objective of this study was to evaluate the effect of an injectable multi-mineral complex supplementation on beef cows overall mineral status and fertility. This study involved 9 different locations in the state of Virginia and a total of 1,128 Angus crossbred multiparous cows. All cows had ad libitum access to forage and water, and received mineral supplementation in form of mineral blocks. All cows were enrolled in a 7-d CO-Synch + CIDR fixed-time AI (FTAI) protocol, followed by natural service for an approximately 70-d breeding season. At the initiation of the FTAI protocol (d 0) cows were stratified by days post-partum (82 ± 18 d) and randomly assigned to one of two treatments: 1) One dose of an injectable trace mineral containing zinc (60mg/ml), copper (15mg/ml), selenium (5mg/ml) and manganese (10mg/ml) on d 0 (n = 560; 1 ml/90 kg BW of Multimin® 90, Multimin USA, Ft. Collins, CO); or 2) a negative control with no trace mineral injection (n = 568). BCS was recorded at d 0, 61 and 121. Estrus detection was recorded at d 10 using an estrus detection patch. Pregnancy was diagnosed on days 71 and 131 by ultrasonography. Liver biopsies were collected on days 0 and 45 in a subgroup of 140 cows from both treatments and distributed among all locations. No differences between treatments were detected in days post-partum (P = 0.83), BCS (P ≥ 0.42) and estrus detection (P= 0.12), neither in mineral status of copper, manganese, selenium or zinc (P ≥ 0.28). No effect of treatment was detected (P ≥ 0.20) in AI pregnancy rate (57%) or overall pregnancy rate (93%). In conclusion, one dose of injectable trace mineral administrated 10 days before AI did not improve pregnancy rate or overall mineral status in multiparous beef cows enrolled in FTAI.
179 Using a 100% Dried Distillers Grains Cube as a Supplement for Steers Grazing Mixed Grass Prairie in Oklahoma
Authors: Grigsby Zane N , Beck Paul A , Gunter Stacey A
Published: November 2020

This research was conducted to determine effects of supplementation and implanting on BW gain by steers grazing mixed grass prairie (n = 12 pastures, 19.9 ± 0.7 ha) in northwest Oklahoma. Three main plot treatments were: 1) Negative Control (NC), no supplementation, 2) Positive Control (PC), supplemented with DDGS cubes, 1.8 kg/steer on alternate days in late summer, 3) High Supplement (HS), 1/3 increase in stocking rate with 0.75% BW supplemental DDGS cubes all season. Steers (n = 125, BW = 223.1 ± 23.2 kg) were stocked at 2.2 ha/steer for PC and NC, 1.3 ha/steer for HS. Grazing was from May 17 – September 27 (132 d). All steers were implanted with 200 mg progesterone and 20 mg estradiol benzoate (SYN, Synonvex S, Zoetis Animal Health) on May 17. On July 18 three reimplant treatments were applied: 1) no reimplant; 2) SYN; or 3) 40 mg trenbolone acetate and 8 mg estradiol (Revalor G, Merck Animal Health). Data were analyzed using the PROC MIXED in SAS as a split-plot experimental design. In early summer HS had 0.26 kg greater (P < 0.01) ADG than NC and PC. Late summer gains of PC were 0.33 kg/d more (P ≤ 0.01) than NC; and HS gained 0.49 and 0.16 kg/day more (P ≤ 0.04) than NC and PC, respectively. Gain per hectare for PC (46 kg/ha) were greater (P < 0.01) than NC (35 kg/ha) and more than doubled (P < 0.01) with HS (89 kg/ha). Reimplanting had no effect on ADG (P ≥ 0.28). Late season supplementation with PC resulted in supplemental efficiency of 2.7 kg supplement/kg added gain compared with NC. Increased stocking rates with season long supplementation in HS resulted in supplemental efficiency of 3.8 kg supplement/kg added gain per hectare. Based on these data, a 100% DDGS cube is an effective supplement option to increase BW gain during the late summer or increase carrying capacity and gain during the summer grazing period in northwestern Oklahoma.
54 Effects of an injectable zinc solution at weaning as an alternative castration method during the backgrounding period in beef bulls
Authors: Cauble Reagan N , Powell Powell G , Kegley Elizabeth , Gadberry Shane , Beck Paul A , Sims Michael , Shelton Cody
Published: November 2020

Castration is a routine management practice performed on an estimated 15 million bull calves each year in the United States. Although castration is a common practice worldwide, the process causes pain and stress that temporarily reduces performance. The objective of our study was to investigate the effects of a novel injectable zinc solution as an alternative castration method on the growth performance, testicular width, and serum testosterone concentrations of weaned beef bulls. Calves (n = 74) were processed at birth and were randomly assigned to 1 of 2 castration methods: 1) negative control, in which calves were surgically castrated at birth, or 2) chemically castrated, in which calves remained intact males until weaning and were chemically castrated with a 1 mL intratesticular injection of zinc solution in each testicle. Data were analyzed using the MIXED procedures of SAS and significance was declared at P < 0.05. Chemically castrated calves were heavier (P < 0.01) throughout the 168-d backgrounding phase compared to steers (285 and 266 kg respectively); however, the overall change in BW (P = 0.73) and ADG (P = 0.81) was similar between castration techniques. Testicular width measurements were greatest on d 28 and returned to baseline weaning measurements by d 56. Testicular width continued to decrease on d 77 and remained constant for the remainder of the backgrounding period (time P < 0.01). Although testicular width decreased, chemically castrating did not affect (time P = 0.17) testosterone concentrations; however, concentrations were numerically lowest on d 28 and 56. Chemically castrating cattle at weaning resulted in greater overall body weights and reduced testicular width during the backgrounding period; however, it did not eliminate testosterone production as compared to surgically castrating at birth. This solution was not effective in bulls at weaning.
33 Determining the feeding value of hulless barley relative to corn in beef finishing rations
Authors: Pent Gabriel J , Wilson Thomas B
Published: November 2020

Hulless varieties of barley have been developed to improve the digestibility of this small grain. The objective of this project was to determine the feeding value of hulless barley relative to corn in a beef-finishing ration. Angus-cross steers (n = 12) were fed rations that included varying ratios of cracked corn and cracked hulless barley. Steers were stratified by body weight (BW) and allotted to one of four rations: corn, 2:1 ratio of corn to barley, 1:2 ratio of corn to barley, and barley. All treatments included concentrate at 85% and baleage at 15% of total ration dry matter (DM). Rations were fed ad libitum on an individual basis using Calan gates. Feed refusals were measured daily. Steers were weighed and ultrasound 12th rib fat thickness (FT) was measured every 28 d. Steers were harvested at a commercial abattoir when average FT exceeded 0.9 cm. Average daily gain (1.2 kg/d), final BW (653 kg), feed to gain efficiency (10.2:1), and final ultrasound FT (0.94 cm) were not different (P ≥ 0.1486) between treatments. Steer DM intake was lower (P ≤ 0.0496) for those fed corn (9.8 kg/d) compared to those fed barley (12.2 kg/d) or a 1:2 ratio of corn to barley (11.7 kg/d); steer DM intake was similar (P ≥ 0.0640) for those fed a 2:1 ratio of corn to barley compared to those fed the other rations. Finishing ration did not affect hot carcass weight (384 kg; P = 0.7158), carcass FT (1.6 cm; P = 0.9511), ribeye area (87.7 cm^2; P = 0.7184), kidney, pelvic, and heart fat (2.6%; P = 0.3842), and yield grade (3.5; P= 0.8802). Feeding hulless barley compared to corn resulted in similar performance and carcass characteristics when included in beef finishing rations although feed intake was greater when barley exceeded 56% of the ration DM.
113 Mineral Supplementation Effects in Stocker Cattle Performance Grazed on Wheat Seeded Native Pastures
Authors: Kipp Kaylee R , Eborn Douglas , Owen Megan P
Published: November 2020

One way to extend the grazing season in the southeast United States is to plant cool-season forages into native pastures to provide additional forages for the winter and spring grazing. The objective of this study was to evaluate the effects of two different medicated (Monensin) supplementation types, with or without protein, on stocker calves grazing native pasture overseeded with wheat through the months of February to May. Cross-bred steers (n = 36; BW = 291.76 kg ± 29.92) and heifers (n = 29; BW = 288.17 kg ± 25.22), sired primarily by Hereford bulls, were assigned to two treatment groups at two locations blocked by sex and weight. All mineral supplementation was provided ad libitum. The first supplementation consisted of a commercial loose mineral (Advanced Mineral Performance Technology (AMPT); ADM; Quincy, Illinois), and the second was a commercial protein block (MoorMan’s, Mintrate Blonde Block RU; ADM; Quincy, IL) containing 42.0% Crude Protein. Average Daily Gain was compared using PROC MIX with the main effects: treatment, pasture, gender, and their interactions. The starting weights of the treatment groups were not different (P = 0.996). No significant interactions (P < 0.05) were detected and only the main effects will be reported. Steers gained more (P < 0.0001) than heifers (1.25 kg ± 0.025 kg vs. 0.96 kg ± 0.029 kg, respectively). ADG for the mineral was 1.14 kg ± 0.027 kg, compared to 1.06 kg ± 0.028 kg for the protein block (P < 0.05). Differences in ADG was observed between pastures (P < 0.07). At 124 days the final body weight of heifers averaged 119.56 kg and the steers averaged 154.70 kg. These results indicate that the mineral improved ADG over the block supplementation.
164 The effects of energy and lasalocid supplementation on forage intake and energetics of cattle grazing wheat pasture
Authors: Pickett Autumn T , Kegley Elizabeth , Beck Paul A , Gunter Stacey A
Published: November 2020

Cattle grazing wheat have the potential to gain BW exceptionally well, but excessive nitrogen intake results in increased excretion and increased greenhouse gas (GHG) emissions. Supplemental grain with the addition of an ionophore given to ruminants grazing wheat is a potential practice for producers to increase nitrogen efficiency while decreasing GHG emissions. Therefore, the objective of this experiment was to quantify the effects of energy and lasalocid supplementation on nutrient intake, respiratory gas fluxes, and performance of grazing cattle. Heifers (n = 18) were used in a 49-d experiment that consisted of two 21-d blocks with 7 d between them (initial BW=311±17.3 kg and 339±16.7 kg, Block 1 and 2, respectively). Heifers were assigned randomly to 1 of 3 treatments; no supplement (Control, n = 6), 2.95 kg control feed/d (Energy, n = 6), or 2.95 kg feed with lasalocid/d (Lasalocid, n = 6). Cattle grazed an 8.1-ha paddock of winter wheat and had access to a GreenFeed system used to quantify the respiratory gas fluxes (CH4, CO2, and O2). Cattle were weighed on d 0 and 21 of each block, on d 15 to 21 cattle were gathered every 12 h and fecal samples were collected. Data were analyzed using the PROC MIXED in SAS. Methane emissions were not affected (P = 0.58) by treatment, but supplemented cattle had greater (P = 0.04) CO2 emissions and O2 consumption (P = 0.03). Hence, ADG tended to be greater for supplemented cattle (P= 0.09) compared to Control (1.22 and 1.00 kg, respectively); but no effect (P = 0.88) was observed for the Lasalocid. Fecal output was greater for supplemented cattle (P < 0.01), but forage intake was lower (P < 0.01) and nutrient intake was higher (P < 0.01) for supplemented cattle compared to Control. Supplemented cattle had lower forage intake with greater CO2 emissions and O2 consumption, but the Lasalocid did not affect any parameter.
44 Effect of Quebracho (Schinopsis balansae) extract inclusion in a high roughage diet upon in vitro gas production
Authors: Batista Luiz Fernando Dias , Rivera Madeline E , Norris Aaron B , Adams Jordan , Cracco Roberta , Jackson Morgan , Tedeschi Luis O
Published: November 2020

The utilization of natural plant secondary compounds as feed additives in animal nutrition has been extensively studied because of their ability to modify digestive and metabolic functions. Condensed tannin (CT) supplementation can potentially alter ruminal fermentation, and mitigate methane (CH4) emissions. The objective of this study was to determine the effect of quebracho CT extract (QT; Schinopsis balansae) within a roughage-based diet on overall fermentability and CH4 production utilizing the in vitro gas production technique (IVGP). Twenty rumen cannulated steers (227 ± 19 kg) were randomly assigned to four dietary treatments (n=4): QT at 0, 1, 2, and 3% of DM (QT0, QT1, QT2, and QT3). A roughage-based diet containing 88% bermudagrass hay and 12% concentrate was fed daily at 2.1% of shrunk body weight. The animals were adapted to the basal diet for 24-d then introduced to predetermined treatments for 35d. Rumen inoculum was collected weekly from each steer to perform the incubations. Two hundred milligrams of air-dried base diet were incubated for 48-h with a composite rumen inoculum for each treatment over 5 wk. Kinetic analysis of cumulative 48h gas production was performed using Gasfit. Measurements of CH4 were performed via gas chromatography and digested residue was determined post-incubation. Data were analyzed using a random coefficients model. Total gas production was higher for QT0 compared to QT1 and QT3 (P = 0.001), but not different from QT2 (P = 0.554). The fractional rate of gas production was higher for QT2 compared to QT0 (P = 0.011). First and second pool gas production decreased linearly as QT inclusion increased (P = 0.042 and 0.010, respectively). There was no dietary effect in ivNDFD (P = 0.567). However, there was a linear tendency to decrease CH4 production with the addition of QT (P=0.071) likely due to changes in the microbial population.
49 Effects of in-vitro digestibility in cannulated steers when supplemented different levels of glycerol
Authors: Gutierrez Noheli , Boyd Jamie A
Published: November 2020

A study was conducted to evaluate effects of increasing concentration of food grade glycerol on rumen environment and nutrient digestibility. Three ruminally cannulated Jersey steers were used in this study. The study was conducted from March to May 2019. Experimental design was a 3x3 Latin square with a 2wk adjustment period followed by a 1wk collection period. Diet was coastal bermudagrass hay based. Different forage types were introduced in the incubation process to evaluate digestibility. Glycerol was administered once a day at 0, 15, or 20% of DMI (dry matter intake). dNDF (digestible NDF) and dDM (digestible dry matter) was determined using an ANKOM Daisy II incubator inoculated with 200g fresh rumen fluid and incubated for 12, 24, 48 and 72 h at 39°C. Each vessel contained ground forage samples in filter bags in triplicate. After incubation, filter bags were rinsed with cold water and dried for 24h in a 55°C forced air oven. Data were analyzed using the Proc MIXED procedure of SAS version 9.4. There was no difference dNDF in effect of different levels of glycerol between forage types by diet. But a numerical tendency was observed that dNDF was decreased at 20% inclusion rates in comparison to 0 and 15% inclusion of glycerol in the diet. Neither steer nor run was significantly different in the study. However as expected digestibility over time was significantly different (P < 0.001). A significant increase was observed in DMI with the increased levels of glycerol in the diet (P = 0.003), both the 15% and 20% levels of glycerol increased in DMI in comparison to the control (0%). It appears based on these study results that digestibility may be inhibited, as levels of dietary glycerol increase in the diet and more work needs to be done to find the optimal level of glycerol supplementation.
188 Voluntary individual intake and performance of mature cows compared to primiparous heifers consuming a low quality forage
Authors: Holder Amanda , Andresen Claire , Gross Megan A , Moehlenpah Alexi , Lalman David L
Published: November 2020

This study investigated production and efficiency of Angus first-calf heifers and mature cows. During late lactation (January through April), cow/calf pairs were provided abundant bermudagrass hay and 2.5 kg of dried distiller’s grains with solubles daily. Milk yield and composition was determined monthly using a milking machine. After weaning, forty-three Angus 2-yr-old heifers (n = 22) and cows (n = 21) were assigned to one of five pens according to their dry matter intake EPD. Each pen was equipped with two SmartFeed individual intake units adapted with a hay basket. Cows had ad libitum access to long stem prairie hay (CP = 5.7%, NDF = 66.4, TDN = 54%). Cows were provided 1 kg corn and 1 kg cotton seed meal daily. Performance variables were analyzed with a mixed model including pen as a random variable and age the fixed variable. Following a 14-day adaptation period, individual cow forage intake was measured for 45 days. There was a positive phenotypic correlation (r = 0.40, P < .01) between residual average daily gain EPD and average study-period BCS on trial. Mature cows consumed 1.9 kg more forage daily (P = 0.05) than heifers although there was no difference when expressed as a percent of BW (2.0%; P > .78). There was no difference in the amount of time spent in feeders between heifers and cows (4.6 hrs, P > 0.59) nor average body condition score (5.1, P > .86). Cows produced more milk per unit of body weight (P < .01) and had greater residual feed intake and calf weaning weight (kg) compared to heifers (0.63 and 211.6 vs -0.45 and 189.3; P < 0.04). Heifers consumed similar amount of forage per unit of BW, spent the same amount of time in feeders and were more efficient in weight gain while consuming low quality forage.
41 Effect of grazing cotton crop residue versus Bermudagrass on performance and economic parameters in late gestation beef cows
Authors: Davis Dylan B , Hernandez Shane r , Stewart Lawton
Published: November 2020

The residual lint, seed, and leaf remaining after cotton harvest was evaluated as a feedstuff to reduce the amount of hay fed to beef cows during early winter. A study was conducted utilizing 36 crossbred Angus cross cows (BW 491.04 kg) in late gestation. Cows were stratified by weight and randomly assigned to one of four groups, and each group was assigned to one of two treatments: Bermudagrass hay (Cynodon dactylon) (HAY), or cotton (Gossypium hirsutum) crop residue + Bermudagrass hay (COTTON). All cattle remained on their respective treatments for 30 d, and BW were recorded before and after the feeding period. Hand-grab samples were collected of cotton residue in each field to quantify residue available at the beginning of grazing. Available residue in the cotton groups were 783.17 kg/acre and 911.13 kg/acre. Core samples were collected from each bale of a single lot of hay. The same lot of hay was used for both treatments. Hay was offered ad libitum for the HAY treatment, and hay was offered to the COTTON treatment, starting on d 19. A completely randomized design was used and data were analyzed using a one way analysis of variance. The CP, NDF, and ADF values for hay and cotton residue were 12.3, 62, and 37%, and 23.5, 66, and 57%, respectively. Average daily gain (1.02 and 0.60 kg) and average weight change (34.5 and 20.4 kg) were higher (P < 0.003) for HAY compared to COTTON cows; however, their subsequent calving and breeding performance in the herd were not affected. Average daily hay disappearance for COTTON (5.90 kg/hd) was lower (P < 0.02) compared to HAY (17.19 kg/hd). Overall daily hay cost per head was lower (P < 0.01) for COTTON compared to HAY ($0.65 and $1.89, respectively). These data show that grazing cotton crop residue can reduce feed cost in late gestation beef cows.
190 Winter vs. year-round supplementation of mature beef cows on feedlot performance and carcass characteristics of steer progeny
Authors: Palmer Elizabeth , Vedovatto Marcelo , Ranches Juliana , Gouvea Vinicius , Oliveira Rhaiza , Poore Matt H , Arthington John , Vendramini Joao , Moriel Philipe
Published: November 2020

This study evaluated the effects of year-round supplementation of molasses/urea or wheat middlings-based range cubes to mature cows on subsequent feedlot growth, immunity, and carcass characteristics of their steer progeny. On d 0, 82 mature Brangus cows were stratified by BW and BCS (433 ± 47 kg; 4.6 ± 0.77) and randomly allocated into 1 of 6 bahiagrass pastures (13–14 cows/pasture). Treatments were randomly assigned to 2 pastures/treatment and consisted of supplementation with molasses/urea during winter (MOL-W), or year-round supplementation with molasses/urea (MOL-Y) or range cubes (CUB-Y). Supplements were isocaloric and isonitrogenous (75% TDN, 20% CP; DM basis) and offered at a total yearly supplement DM amount of 272 kg/cow. On d 423, all calves were weaned, and 33 steers were randomly selected for the feedlot phase. Steers were penned based on cow prepartum pasture distribution and managed similarly until slaughter (d 661). Data were analyzed as complete randomized design using MIXED procedure of SAS, pasture as the experimental unit, treatment as fixed effect, and pasture(treatment) and steer(pasture) as random effects. Dry matter intake did not differ (P ≥ 0.70), but MOL-Y and MOL-W steers had greater (P = 0.05) overall ADG vs. CUB-Y steers. Plasma haptoglobin concentrations tended (P = 0.06) to be greater for CUB-Y vs. MOL-W, and intermediate for MOL-Y. Serum titers against bovine viral diarrhea virus-1 and parainfluenza-3, hot carcass weight, REA, and YG did not differ (P ≥ 0.16) among treatments, but back fat thickness was greater (P = 0.03) for MOL-W vs. MOL-Y and CUB-Y. The percentage of carcasses grading Choice did not differ (P = 0.35) among treatments, but more carcasses tended (P = 0.08) to grade low Choice for MOL-W vs. CUB-Y and MOL-Y. Therefore, providing molasses/urea supplementation to mature beef cows during winter only or year-round increased steer post-weaning feedlot performance and carcass quality compared to steers born from cows offered year-round supplementation with range cubes.
51 Effects of acclimation on cattle response to humans while being handled
Authors: Hemphill Corban H , Reuter Ryan R , Neel James P , Goodman Laura
Published: November 2020

The objective of this study was to evaluate the impact of previous human interaction on the behavior of beef cows while they are being handled. To achieve this, 84 F-1 Angus x Brahman cows were randomly assigned to one of two human interaction treatments. The positive human-animal interaction group (P) was subjected to daily contact with a herdsman (on foot) for 15 minutes and was fed supplement by the herdsman. The control group (N) was checked daily and fed from a vehicle, with no direct human interaction. Each acclimation procedure was replicated in 2 pastures/herds (n = 16 to 26 cows in each herd). During routine processing times for these herds (d 0, 256, and 317), herds were gathered from their pastures and temperament was assessed. Chute and alley scores were assigned to individual animals by the same trained observer and ranged from 1 (calm) to 5 (aggressive). Chute exit velocity was also measured. Temperament variables were evaluated with ANOVA as a split plot with acclimation procedure in the whole plots and pasture as the whole-plot experimental unit, and processing time in the split plot. Neither human interaction (P = 0.99) nor time (P = 0.13) affected chute exit velocity. Chute score increased through time (P = 0.01) but was not affected by human interaction (P = 0.70). Alley score was not affected by human interaction (P = 0.32) or time (P = 0.81). Neither time nor the specific type of human acclimation we implemented affected cattle temperament, indicating other traits may be more important. Alternatively, different acclimation procedures may be more effective to improve cattle temperament.
38 Effect of Breed on Dairy Calf Vigor from Birth to Preweaning
Authors: Meza Michelle P , Turner Caitlin M , Powers Chad M , Sexten Andrea K
Published: November 2020

There is a stigma in the dairy industry that Brown Swiss calves are not as quick to stand and nurse following birth compared to other dairy breeds. The objective of this study is to determine if Brown Swiss calves are less vigorous at birth and if this affects their health status and early calf growth compared with the dairy industry’s most prominent breed, the Holstein. All calves (n = 25) were scored shortly after birth using a modified Apgar scoring system used for infants. Thirteen parameters divided into 5 categories were evaluated to determine overall vigor of each calf. These included visual scores for meconium staining and swelling of the head; initial mobility scores for time to lift head, time to stand, and ear position; general responsiveness scores included strength of the suckling reflex, head shake in response to straw in nasal cavity, tongue withdrawal when pinched, and eye reflex; oxygenation score for mucus membrane color; rates scores included heart rate, respiration rate, and temperature. In addition to the vigor scoring, a weight was taken at birth and 2 weeks post calving. Jugular blood samples were collected at birth, 24 hours later, and at 2 weeks of age, and serum was stored for later analysis of haptoglobin and IgG concentration. Vigor scores and weight data were analyzed by breed using the mixed procedure in SAS. The vigor score for suckling reflex was lower (P = 0.04) for Brown Swiss calves (1.69, n = 12) than Holstein calves (2.39, n = 13). A weakened suckling reflex can lead to more challenges when consuming colostrum. Early colostrum intake is vital to obtaining passive immunity and maintaining health status in young calves. All other vigor scores collected for the Brown Swiss and Holstein calves did not differ (P > 0.05).
167 The effects of fly control strategies on fly abundance, fly avoidance behaviors, and performance in feedlot bulls and steers
Authors: McNeff Courtney , Talley Justin , Robison Colton A , Wilson Blake K
Published: November 2020

The objective of this experiment was to examine the effects of fly control strategies on fly abundance, fly avoidance behaviors, and animal performance in a feedlot setting. Angus bulls (n = 64; BW = 281 ± 36.2 kg) and steers (n = 36; BW = 475 ± 40.4 kg) were blocked by sex and BW and assigned to 1 of 4 experimental treatments in a randomized complete block design (7 pens/treatment; 4 bulls/pen; 3 steers/pen). Treatments included: control (CON; no fly control), abamectin and piperonyl butoxide insecticide tags (FT; XP820®, Y-Tex Corporation, Cody, WY), permethrin and piperonyl butoxide pour on (PO; Permectrin® CDS, Bayer Animal Health, Shawnee Mission, KS), or a garlic-powder top dress (GR) administered at 0.28 g • -1 animal • -1d. The experiment was conducted between June and September. Horn and stable fly abundance (FA) and fly avoidance behaviors (FAB; i.e. tail-flicks, stomping, head-tossing) were recorded by trained personnel. Both FA and FAB were recorded once/wk on days with similar temperatures, humidity, wind speed, and without precipitation based on Oklahoma Mesonet data (Stillwater site). There was a tendency for a treatment × time interaction for horn FA with differences in treatments occurring at wk 1, 2, 8, and 14. There was no treatment × time interaction for stable FA or FAB, however both were affected by time (P < 0.001). There were no differences in final BW (P = 0.34), overall ADG (P = 0.30), overall DMI (P = 0.53), or overall G:F (P = 0.39). There was a tendency (P ≤ 0.10) for GR to have decreased BW on d 28 and decreased ADG from d 0 to 28 compared with FT and PO. There was also a tendency (P = 0.09) for decreased DMI from d 0 to 56 for GR compared to CON and FT. Overall FA was less than expected (mean = 1 to 17 flies/animal) throughout the experiment and overall animal performance was unaffected by fly control strategy.
148 The effect of bunk preference on performance, intake, and efficiency of feedlot steers using an automated individual feeding system
Authors: Pierce Kaitlyn N , Reuter Ryan R , Robison Colton A , Wilson Blake K
Published: November 2020

Automatic feeding systems are being used more frequently to understand individual cattle behavior and intake variation when cattle are group housed. The objective of this experiment was to evaluate if bunk preference exists, and if so, how bunk preference affects performance, intake, or efficiency of feedlot steers. Angus steers (n = 123; initial BW = 293 ± 33.8 kg) were blocked by BW and sire and assigned to 1 of 4 pens, each containing 6 automated feed bunks (Insentec RIC; Hokofarm Group, Marknesse, Netherlands), in a randomized complete block design. Steers were fed a common diet and free to consume feed from any bunk within the pen without restriction. A steer’s preferred bunk was defined as the bunk from which the most feed was consumed. In any week, 80% of steers consumed less than 29% of that week’s total feed intake from the preferred bunk, indicating no strong preference for a specific bunk. The maximum weekly feed intake consumed from a preferred bunk was 57%. Further, the percentage of intake from the preferred bunk did not affect overall ADG, feed intake, or G:F (P > 0.64). These results suggest that a few steers may have a relatively strong preference for a specific feed bunk; however, this preference was not associated with performance, intake, or efficiency. Researchers can design experiments (at a stocking density of 5 steers per bunk) that restrict or alter an individual animal’s access to any specific bunk, because such access, or lack of access, does not alter the animal’s performance or feed intake.
150 The effect of competition for an automated supplement feeder on supplement intake behavior of stocker steers
Authors: Husz Taylor C , Goad Carla , Reuter Ryan R
Published: November 2020

The objective of this research was to determine the effect of competition for a feeding space at an automated supplement feeder on supplement intake behavior. A 2 yr study was conducted; each yr, 128 mixed-breed beef steers (n = 256, initial BW = 245 ± 27.5 kg) were randomly assigned to 8 paddocks. One paddock each yr (n = 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 had 4 feeding stations that dispensed supplement after eligible animal’s RFID tags were read by the electronics of the feeder. Steers were limited to 0.50 kg supplement/d. Weekly, additional paddocks were commingled with the tester paddock to increase competition for the feeder. This resulted in a stocking density from 4 to 32 steers per feeding station. For yr 2, one feeding station was disabled, resulting in a stocking density of 5.3 to 42.7 steers per feeding station. Approximately 31% of the steers did not voluntarily use the feeder; therefore, effective competition was less than the study design. Mean weekly supplement intake and GPS location were recorded for steers in the tester paddock. Additionally, pedometer data were collected in yr 2. Weekly mean supplement intake and time spent near the feeder were regressed on actual feeder stocking density with yr as a random variable; wk was the experimental unit (n = 16 wk). Tester steers consumed an average of 0.27 kg supplement/d. Competition for a feeding station numerically reduced (P = 0.01) supplement intake by 5 g/d per steer of additional competition. Steers spent 4.4% of the time within 15 m of the feeder regardless of competition (P = 0.54). As competition increased, steers took more steps (P < 0.01). These data illustrate that in environments similar to this experiment, the feeder can be stocked with at least 20 animals per feeding station with minimal effects on supplement intake.