Performance Of Steers Research Articles

Effects of feeding wood kraft pulp silage containing sweet-potato shochu distillery by-product on feed intake, feed digestibility, rumen fermentation, blood components, and growth performance in Japanese Black fattening steers during early period.

The effects of long-term feeding of wood kraft pulp (KP) silage containing sweet-potato shochu distillery by-product (SDP) on feed intake, feed digestibility, rumen fermentation, and growth performance of Japanese Black steers were investigated during the early fattening period. Ten Japanese Black steers (9.8 ± 0.6months of age) were used in this study. Five steers (KP group) were fed KP silage as a replacement for 10% timothy hay (dry matter bases), in contrast to the other five (control group). KP silage consisted of 92.9% KP and 7.1% SDP (dry matter bases). The experiment was conducted for 18 weeks. No significant differences were observed in terms of feed intake, feed digestibility, or daily body weight gain between the groups. In addition, diurnal changes in the rumen pH and ruminal lipopolysaccharide activity did not differ between the groups. However, the plasma concentration of aspartate transaminase in the KP group was slightly lower (P = 0.078) than that in the control group. Thus, our study suggested that feeding KP silage does not reduce feed intake or affect the rumen fermentation or growth performance of Japanese Black fattening steer.

Effect of Feeding Interval on Finishing Performance of Beef Steers

It has long been accepted that optimal performance in beef cattle occurs when cattle are fed at a similar time each day. In fact, in Frederick Mumford’s Syllabus of Illustrated Lecture on Profitable Cattle Feeding published by the U.S. Department of Agriculture in 1905, Mr. Mumford stated, “Cattle should be fed at certain hours and in the same way. This cannot be varied 15 minutes without some detriment to the cattle.” Little research has been conducted examining interval of feed delivery. Most feedlot research examining feed delivery has focused on the comparison of once or twice daily feed delivery on animal performance. The current research examined beef steer finishing performance with stable or variable once daily feed delivery.

Avaliação da eficácia, inocuidade e depleção residual da flavomicina em novilhos confinados

Abstract Flavomycin is a non-ionophore additive little studied in finishing confined cattle. Therefore, this study aimed to evaluate the effectiveness of flavomycin on productive performance, ingestive behavior, carcass traits and biochemical parameters of steers finished in confinement. 32 whole steers, ½ Angus e ½ Nellore blood, from the same herd, with a mean age of 11 ± 1.5 months and initial body weight of 337 ± 6 kg were evaluated. The experiment was a randomized block design, consisting of two treatments and eight replications, as follows: Diet without flavomycin (control) and Diet with flavomycin (0.5 g FLAVIMPEX®80 animal day-1). There was no difference between treatments, the average dry matter intake of the animals was 10.03 kg day-1, feed efficiency was 0.158 kg, average daily gain was 1.593 kg day-1, apparent diet digestibility was 61.69%. The use of flavomycin was not effective in animal performance, and caused no changes in ingestive behavior and carcass traits of the animals. Total Plasma Protein, Aspartate amino-transferase and creatinine were lower for animals supplemented with flavomycin compared to the control group. In relation to the experimental period, there was a reduction in the levels of Total Plasma Protein, an increase in albumin, Gamma-Glutamyl Transferase and urea in cattle, but all remained within the reference range for the species.

Influence of supplemental condensed tannins on initial 112-d feedlot growth-performance and characteristics of digestion of calf-fed Holstein steers.

In experiment 1, 150 calf-fed Holstein steers (119±6kg) were used to evaluate the effects of level of supplemental condensed tannin (0, 14, and 28g/kg diet DM) in a conventional steam-flaked corn-based growing-finishing diet on feedlot growth performance. There were no treatment effects on growth performance during the initial 56-d period. However, during the subsequent 56-d period, supplemental condensed tannin tended to increase average daily gain (ADG; linear effect, P = 0.09). The increase in ADG was consistent with the tendency for increased dry matter intake (DMI; linear effect, P = 0.08). Hence, differences in gain efficiency during the second 56-d period were not appreciably affected (P = 0.80). Supplemental condensed tannin did not affect overall (112-d) ADG, DMI, gain efficiency, or dietary NE. In a second experiment, six Holstein steers (179.4±7.9kg) with cannulas in the rumen and proximal duodenum were used in a replicated 3×3 Latin square design to evaluate treatment effects on characteristics of ruminal and total tract digestion. Treatments were the same as in Trial 1. Tannin supplementation decreased (linear effect, P = 0.03) ruminal OM digestion and tended to decrease (linear effect, P = 0.06) ruminal feed N degradation. Tannin supplementation decreased (linear effect, P = 0.03) ruminal pH, but did not affect (P > 0.20) ruminal molar proportions of volatile fatty acids and estimated methane production. In current study, supplemental tannin had marginal effects on overall growth performance of calf-fed Holstein steers, but reduced ruminal, postruminal, and total tract nitrogen digestion.

Data-driven Steering Torque Behaviour Modelling with Hidden Markov Models

Modern Advanced Driver Assistance Systems (ADAS) are limited in their ability to consider the driver's intention, resulting in unnatural guidance and low customer acceptance. In this research, we focus on a novel data-driven approach to predict driver steering torque. In particular, driver behavior is modeled by learning the parameters of a Hidden Markov Model (HMM) and estimation is performed with Gaussian Mixture Regression (GMR). An extensive parameter selection framework enables us to objectively select the model hyper-parameters and prevents overfitting. The final model behavior is optimized with a cost function balancing between accuracy and smoothness. Naturalistic driving data covering seven participants is obtained using a static driving simulator at Toyota Motor Europe for the training, evaluation, and testing of the proposed model. The results demonstrate that our approach achieved a 92% steering torque accuracy with a 37% increase in signal smoothness and 90% fewer data compared to a baseline. In addition, our model captures the complex and nonlinear human behavior and inter-driver variability from novice to expert drivers, showing an interesting potential to become a steering performance predictor in future user-oriented ADAS.

A Skid-Steering Method for Path-Following Control of Distributed-Drive Articulated Heavy Vehicles

Distributed-drive articulated heavy vehicles (DAHVs) have separate front and rear sections and require a complex hydraulic steering system to achieve the steering process, which poses considerable challenges in obtaining better steering characteristics and achieving path-following control. In this paper, the distributed-drive characteristic of DAHVs is used to develop a novel skid-steering method (SSM) in which the hydraulic steering method (HSM) is replaced with a system that differentially controls the driving wheels to improve vehicle steering performance and path following control accuracy. Three main contributions are made: 1) The novel SSM with direct yaw moment that is used to be the sole power source during steering process of DAHVs is designed to replace the conventional HSM. 2) The idea of SSM by yaw rate control of one vehicle section to achieve the steering process for DAHVs is proposed firstly, which can solve the complex problem of requiring multiple control parameters due to the separate vehicle sections of DAHVs. 3) A layered control method is implemented to improve the robustness of the control system, which is composed of an upper path following controller and a lower skid steering controller combined with a double sliding mode control technique. The system’s stability and robustness are proven by the Lyapunov approach. A co-simulation model verified by field tests is used to demonstrate the feasibility and effectiveness of the proposed control method. The results of this study provide a new way to improve the intelligence of DAHVs.

Curvature estimation of track using a front view camera

Active steering is one of the methods to improve the curve passing performance of railway vehicle. It improves steering performance by driving the actuator in accordance with the curvature. Curvature is a necessary parameter for active steering. This paper proposes a method for estimating curvature of track using a front view camera. The proposed system can be divided into three parts. First, semantic segmentation is performed to estimate the position of track from camera images. Second, the track position and radius are calculated by performing circular and straight-line fitting based on the estimated track position used semantic segmentation. Finally, the proposed system calculates the mean squared error of the track position estimated by semantic segmentation and the track position calculated by circular or straight-line fitting, and the proposed system is determined whether the track section is a straight or curved section. Furthermore, the proposed system is verified by using a 1/10 scale model experimental vehicle. Validation results show that the proposed system is capable of estimating curvature of track.

S-대역 레이다용 소형 다기능 투과형 메타표면 단위셀 설계 및 검증

In this study, miniaturized unit cell design and verification of multi-functional transmissive meta-surface for S-band radar are presented. The proposed unit cell comprises a receiver (Rx) antenna, a miniaturized reflection-type phase shifter, a PIN diode switch for polarization selection, and a dual-pol transmitter (Tx) antenna. The Rx/Tx antennas are stacked patch type antennas, and the reflection-type phase shifter, which has a smaller area of 36 % than a conventional hybrid coupler, controls the phase shifting from 0 to 330°. The PIN diode switch uses a −5 V reverse DC voltage bias to handle high input radio frequency (RF) power of 23 dBm. Moreover, a 1×2 unit cell array was fabricated to verify the unit cell performance. The array antenna freely converted polarized waves (horizontal/vertical) and exhibited beam steering performance in a range of approximately 50°.

Dynamic Guidance Performance of Gdbacuo and Ybacuo Bulk Single Grain Superconductors Under a Varying External Magnetic Field

Dynamic Guidance Performance of Gdbacuo and Ybacuo Bulk Single Grain Superconductors Under a Varying External Magnetic Field

Performance and parasitological parameters of steers sequentially grazed with lambs

In the majority of mixed or sequential gazing studies with sheep, cattle performance remained unaffected. However, the treatment regime of the sheep in these studies was often intense and this may have limited cross-transmission of nematodes from sheep to cattle. We conducted a sequential grazing trial with cattle and sheep with moderate anthelmintic intervention. Twenty first season grazing steers were stratified to 10 couples according to their origin, egg excretion per gram faeces (EPG), metabolic weight and previous weight gain record. Thirty naturally infected ewe lambs were stratified to 5 groups according to metabolic live weight and EPG. Five pairs of the steers were sequentially grazed with the 5 groups of lambs whereas another five pairs of steers served as control. Grazing duration was 70 days with a subsequent indoor period of additional 35 days for the steers. Weight and EPG was recorded 3 days before and 27, 49, 70 and 105 days after trial start. The recorded live-weight of the sequentially grazed steers was 182 ± 14, 191 ± 11, 205 ± 15, 219 ± 15 and 236 ± 18 and the live-weight of the control steers was 180 ± 18, 193 ± 19, 203 ± 21, 217 ± 24 and 234 ± 24 kg respectively. The EPG of the sequentially grazed steers 3 days before grazing start and at day 27, 49, 70 and 105 was 94 ± 100, 95 ± 48, 49 ± 42, 58 ± 41 and 140 ± 73 EPG respectively. The EPG of the control steers at the same dates was 96 ± 82, 98 ± 24, 104 ± 77, 98 ± 71 and 270 ± 287 EPG respectively. The sequentially grazed steer groups did not differ from the control groups with regard to EPG, live weight and daily weight gain. However, the sequentially grazed steers showed elevated pepsinogen levels compared to the control steers (e.g. 3.34 ± 1.05 units tyrosine and 1.29 ± 0.50 units tyrosine after 70 days of grazing, respectively). Larval samples from individual steer coprocultures of both groups were tested PCR-positive for Cooperia oncophora, Ostertagia ostertagi and Haemonchus contortus. We conclude that short term sequential grazing of first season grazing steers with lambs excreting mainly eggs of Haemonchus spp. did not adversely affect steer performance despite increased pepsinogen values. However, hot and dry conditions may have had a suppressive effect on larval development, migration and finally uptake by the steers.

A simple configuration of beam steering substrate integrated waveguide aperture antenna loaded with metamaterials

AbstractThis letter presents a novel broadband substrate integrated waveguide aperture antenna with simple structure and beam steering performance. By using the left‐hand and band gap characteristics of the mushroom‐shaped metamaterials, the main beam of the substrate‐integrated waveguide aperture antenna can be easily switched between the back‐fire and boresight directions. Above all, the beam scanning characteristic does not depend on three‐dimensional structures or complex loaded structures, therefore it is a promising technology for designing planar two dimensional beam steering array. Experimental results indicate that the impedance bandwidth of the antenna covers the frequency range from 13.3 to 16.7 GHz and the relative bandwidth is 22.7%. The accordance between the simulated and measured E‐plane radiation pattern of the antenna at three representative frequencies verifies the beam steering capability of the proposed antenna.

Effect of frequency of protein energy supplementation on the performance of Nelore steers during the dry season

The objective of this study was to evaluate the effect of the frequency of provision of protein energy supplementation on pasture during the dry period of the year on the performance of Nelore steers in rearing phase. FAZU teaching school conducted the experiment from July to September 2017. Twenty-two animals of the Nelore breed, aged 12 months and mean initial weight of 232.22 (± 20) kg, modules of 2 ha each, subdivided in six paddocks of Panicum maximum cultivars Mombaça and Tanzânia. The experimental design was completely randomized (DIC) and the averages were compared by the Tukey test at 5% significance. There was no significant difference between the three frequencies of supply of energy protein supplementation, in relation to the average daily weight gain, which were 837; 881 and 855g, at the frequencies of 7; 5 and 3 times per week, respectively. However, there was a significant difference (P <0.05) for the mean daily weight gain between the treatment in which the animals received mineral supplementation (434g), which was lower than the treatments in which the animals were fed with protein energy supplement at the level of 0.25% of body weight. In conclusion, during the period and in the evaluation conditions of this experiment, there was no difference in the effect of the frequency of supply of a protein energy supplement in the supply level of 0.25% of the animals' body weight. The average daily gain was higher for the animals that received the protein energy supplement compared to those supplemented with mineral. Five times a week supplementation obtained the best economic benefit among the evaluated frequencies.

A novel electro-hydraulic servo steering system for Ackermann steering of heavy multi-axle vehicle

Ackermann steering is important for the steering performance of heavy multi-axle vehicle. When Ackermann steering condition is not satisfied, it will lead to abnormal tire wear. Traditional trapezoidal mechanism of heavy multi-axle vehicle is a single degree of freedom (DOF) mechanism, which is difficult to completely realize Ackermann steering. In this paper, a new two DOF electro-hydraulic servo steering system (TDEHSSS) by using a variable length tie rod is proposed for solving the issue. First, a complex nonlinear dynamic model of TDEHSSS is established. This model includes the two DOF mechanical model based on a Lagrange equation, the valve-controlled double steering power cylinders model and the valve-controlled tie rod cylinder model. Then, a simulation model is built through MATLAB/Simulink and the simulation results show that TDEHSSS can realize the proposed requirement. At last, a test bench is founded to verify model. It is indicated that the simulation and experimental curves are consistent, showing that mathematical model is in accordance with the experimental system. This research is valuable for analyzing TDEHSSS, designing advanced controllers, and finally realizing Ackermann steering for heavy multi-axle vehicles.

Academic Supervision and Guidance and Counseling Teacher Self-Efficacy at the State Junior High School Level

There is only one management function involved in the management of advice and counseling, which is controlling (supervision). Supervision is an essential component of the guidance and counseling program. As a result, academic monitoring implemented by both school supervisors and school principals is linked to the professional performance of guidance and counseling teachers. The purpose of this study is to investigate the impact of academic supervision implementation on the professional performance of guidance and counseling teachers using self-efficacy as an intervening variable. This study employs quantitative tools and a correlational research design. The study involved guidance and counseling teachers from the State Junior High School in Pemalang Regency. According to the study's findings, academic monitoring by school supervisors is still not equivalent since the number of school supervisors is still limited compared to the number of schools and teachers in the Pemalang Regency. However, the study's findings also suggest that academic supervision impacts the professional performance of guidance and counseling teachers at SMP Negeri Pemalang Regency. Furthermore, this element of self-efficacy demonstrates that the outcomes have no substantial positive influence. That is, academic supervision does not mediate between Guidance and Counseling teachers' professional performance.

Interaction of early metabolizable protein supplementation and virginiamycin on feedlot growth performance and carcass characteristics of calf-fed Holstein steers.

One hundred sixty-eight Holstein steer calves (133.4 ± 7.9 kg) were used to evaluate the influence of virginiamycin (VM) supplementation on cattle growth performance and liver abscess incidence, and the effect of feeding 100% vs. 87% of metabolizable protein (MP) requirements during the initial 112 d on growth performance, efficiency of energy utilization, and carcass characteristics. Steers were balanced by weight and assigned to 28 pens (6 steers/pen). During the initial 112-d feeding period, dietary treatments consisted of two levels of MP (100% vs. 87% of expected requirements) supplemented with or without 22.5 mg/kg VM in a 2 × 2 factorial arrangement. There were no VM × MP supplementation interactions (P ≥ 0.14) on any of the parameters measured in both experiments. Calf-fed Holstein steers supplemented with VM increased (P ≤ 0.03) overall average daily gain (ADG), feed efficiency (G:F), observed/expected net energy (NE) values for maintenance and gain, and final body weight (BW). Cattle fed VM also increased (P ≤ 0.04) carcass weight, dressing percent, and longissimus muscle area. However, there was no effect (P ≥ 0.22) of VM supplementation on any other carcass characteristics. Calf-fed Holstein steers fed 100% MP requirements during the initial 112-d feeding period had greater (P ≤ 0.02) ADG, G:F, observed/expected NE values for maintenance and gain, and live BW compared with steers fed 87% of the expected MP requirements. However, there was no effect (P ≥ 0.17) of MP supply during the initial 112-d period on overall (342 d) growth performance measurements. The incidence of liver abscesses was low (averaging 7.7%) and not affected by dietary treatments. We conclude that, independent of MP supplies, supplemental VM enhances overall growth performance and efficiency of energy utilization of calf-fed Holstein steers.

Effects of overseeding red clover in endophyte-infected tall fescue pastures on steer physiology and performance

The objective of this research was to determine the effects of overseeding red clover on cattle grazing endophyte-infected tall fescue (E+ TF) pastures. A grazing study was conducted in the springs of 2016 (75 d) and 2017 (61 d). Before the start of the study, four 3-ha pastures with cool-season grass (predominately E+ TF) were blocked and randomly assigned to a control treatment (TF CON) or a broadcasted red clover treatment (TF+RC). Steers (n = 6 tester steers per pasture) were allocated to each pasture by BW. Pastures were divided into two 1.5-ha paddocks to allow for 14-d rotational put-and-take stocking. Serum prolactin was assayed on the last day of grazing, and selected tester steers from each pasture (n = 3) were moved to pens for Doppler ultrasound measurements, 7 d after grazing. Data were analyzed by repeated measures using the mixed procedure of SAS. Red clover was successfully established in TF+RC pastures (2016: 36% and 2017: 57%, pasture ground cover). The TF+RC pastures had less ADF and NDF and more true in vitro digestible DM than TF CON pastures after grazing ( P < 0.01, in all cases). However, there was no effect of TF+RC on forage mass ( P = 0.08) or pasture carrying capacity ( P = 0.19). Steers grazing TF+RC pastures had 53% and 58% greater ADG ( P = 0.03) and BW gain per hectare ( P = 0.01) than TF CON steers, respectively. Serum prolactin at the termination of grazing was almost 3 times greater in TF+RC steers than in TF CON steers ( P = 0.01). Additionally, 7 d after grazing, TF+RC steers had 44% larger caudal artery luminal areas than TF CON steers ( P < 0.01). Overseeding red clover in E+ TF pastures is an effective strategy for reversing the adverse effects of fescue toxicosis and improving cattle performance.

Implementation of Steering Process For Labriform Swimming Robot Based on Differential Drive Principle

The aim of this study is to develop a swimming robot with good steering performance, in which the steering behavior is achieved by one degree of freedom (1-DOF) represented by a two concave-shaped pectoral fins. The steering mechanism adopted here based on differential drive principle. This principle is carried out by varying the right/left fins velocities. Different radii have been achieved with four different cases of velocities. The proposed design has been validated theoretically via Solidworks{\textregistered} platform and proved practically in a physical swimming pool. A minimum turning radius achieved is 0.40 of body length (BL).

Impacts of added roughage on feedlot performance, digestibility, and ruminal fermentation characteristics of steers fed wheat-based feedlot diets

Impacts of added roughage on feedlot performance, digestibility, and ruminal fermentation characteristics of steers fed wheat-based feedlot diets

Effects of dietary copper supplementation on performance, carcass characteristics, and lipolytic rate of beef steers fed ractopamine hydrochloride

Effects of dietary copper supplementation on performance, carcass characteristics, and lipolytic rate of beef steers fed ractopamine hydrochloride

Effect of a reduction in linear bunk space on feedlot steer performance and body composition

Effect of a reduction in linear bunk space on feedlot steer performance and body composition