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THE EFFECT OF GROWTH-PROMOTING IMPLANTS AND FEEDING DURATION ON LIVE PERFORMANCE AND BEHAVIORAL CHARACTERISTICS, BIOMETRIC MEASUREMENTS, EMPTY BODY COMPOSITION, AND ENERGY RETENTION OF SERIALLY-HARVESTED BEEF STEERS
No full textThe current study strives to understand the effects of an extended release trenbolone acetate + estradiol-17β growth promoting implant upon live growth performance, feeding behavior, skeletal growth, and empty body composition of crossbred beef steers over a feeding period of 378 d compared to non-implanted controls.
In experiment 1, Charolais x Angus steers {n = 80; start of trial body weight (BW) 271 ± 99 kg} were randomly allocated to implant treatment and harvest date in a 2 x 10 factorial experiment. Steers were paired within genetic group according to initial BW, frame score, and adjusted final body weight (AFBW). Within each pair, a steer was randomly allocated to one of two treatments; implanted with Revalor-XS (REV; 200 mg TBA + 40 mg E2 containing 4 uncoated pellets and 6 pellets with a proprietary time release coating technology) on d 0 and d 190 or non-implanted control (CON) to represent a non-hormone treated cattle (NHTC) marketing strategy. Eight steers comprised of 4 pairs were randomly assigned to 1 of 10 harvest dates at d 0, 42, 84, 126, 168, 210, 252, 294, 336, and 378 DOF. Steers were fed in open lot dirt surface pens (20 animals/pen) equipped with 4 GrowSafeTM nodes per pen. Body weight was recorded at each harvest period and individual consumption data were recorded multiple times per day via electronic identification (EID) reads every second. Average daily gain (ADG) was 9.4% greater (P < 0.01) for REV steers (1.42 kg REV vs 1.30 kg CON) during the 378d trial. Dry matter intake (DMI) did not differ (P = 0.15) between treatments but averaged 8.7 kg during the trial and decreased (P < 0.01) in a quadratic manner from 3.2% of BW during the initial period to 1.03% of BW after 378 DOF. Implanting with REV improved (P < 0.05) gain to feed ratio (G:F) by 8.2% during the trial, however a TRT x DOF interaction (P < 0.05) occurred after 293 DOF whereby REV steers became less efficient. Consumption visit frequency was 48.8 events/d during the initial period and decreased (P < 0.01) during the trial ending at 16.1 events/d. Daily consumption time began at 111 min/d during the initial period and decreased (P < 0.01) by 0.12 and 0.15 min/d for CON and REV, respectively. Implanted steers spent approximately 8 and 7.5 min/d less (P < 0.01) visiting and consuming feed, respectively. Singular consumption visits lasted 2.80 min/event during the initial period and increased (P < 0.01) 0.1 min/event for each 42 d period. Dry matter intake per consumption event began at 2.5 kg/event and increased (P < 0.01) 0.3 kg/event for each 42 d period. Implanted steers consumed 0.05 kg DM more (P < 0.01) per consumption event than CON. Consumption rate for each consumption event was greater (P < 0.01) for REV (290 g/min CON vs. 422 g/min REV). These data indicate live growth performance and feeding behavior were impacted by both growth enhancement technology and duration of finishing.
In experiment 2, 24 h prior to each of the 10 harvest dates, all steers were measured for hip height, rump length, hip width, shoulder height, 2/3 body length (BL), body depth, body width, and frame score. Forty-eight h after harvest, a digital image was obtained of the lateral aspect of the right side of each carcass. Carcass area, maximum length and width were digitally measured against a common standard. Body width was 1.17 cm greater (P < 0.01) in REV steers and 2/3 BL tended (P = 0.06) to be greater in CON steers. Hip height increased (P < 0.01) 0.05 cm each d during the 378 d feeding period. Rump length increased (P < 0.01) 0.03 cm/d. Hip width increased (P < 0.01) 0.06 cm/d. Shoulder height increased (P < 0.01) 0.06 cm/d. Two-thirds BL increased (P < 0.01) 0.11 cm/d. Body depth increased (P < 0.01) 0.07 cm/d. Body width increased (P < 0.01) 0.04 cm/d. Steers administered REV yielded 516 cm2 greater (P < 0.01) surface area on ½ of the carcass, or one side, than CON; moreover surface area increased 21.0 cm2 /day. No TRT effect (P = 0.57) was observed for maximal carcass length, however maximal carcass width was 3.9 cm greater (P < 0.01) for REV steers. Steer carcasses increased 0.16 cm/day in length and 0.07 cm/day in width. These data indicate biometric measurements and carcass dimensions were impacted by both growth enhancement technology and duration of finishing.
In experiment 3, during harvest and fabrication, samples were collected to determine empty body composition via proximate analysis of blood, hide, internal cavity components, bone, and carcass soft tissue. Proximate analysis of each tissue was multiplied by mass to assimilate empty body percentages of moisture (EBM), crude protein (EBP), ether extractable fat (EBF), and ash (EBA). Retained energy (RE) was calculated as the difference between the baseline steers (n = 8; initial steers harvest on d 0) and those representing each treatment across harvest endpoints, as was empty body weight gain (EBWG), hot carcass weight gain (HCWG), and ratio of HCWG to EBWG. Metabolic ratio (MR) was calculated as the ratio of RE to daily megacalorie consumption (DMC). Using individual laboratory results for each animal, the difference in total energy was calculated and averaged by treatment and harvest day by subtracting values for each animal from the mean of the baseline steers. Moisture, protein, fat, and ash accretion (MA, PA, FA, AA, g/d, respectively) was calculated as the difference measured in grams per day on trial amongst each treatment and harvest endpoint with the baseline steers representing d 0. Empty body moisture decreased (P < 0.01) in a quadratic trend at approximately 0.0373%/d beginning at 61.9% on d 0 and ending at 47.8% on d 378. Empty body protein decreased (P < 0.01) linearly by approximately 0.0071%/d beginning at 18.7% on d 0 and ending at 16.0% on d 378. Empty body fat increased (P < 0.01) in a quadratic trend at approximately 0.0450%/d beginning at 14.0% on d 0, until d 294 and plateaued at approximately 32.0% through d 378. Empty body ash remained constant (P = 0.29) over the feeding period (5.5% - 5.8%). Empty body protein (16.7% CON vs 17.4% REV) and EBA (5.4% CON vs 5.7% REV) were greater (P < 0.01) for REV steers, and EBM (50.7% CON vs 51.6% REV) tended to be greater (P = 0.07) for REV steers. In contrast, EBF (27.3% CON vs 25.3% REV) was greater (P < 0.01) for CON steers. Ratio of EBP to EBF was less (P < 0.05) for CON steers (0.692:1) compared to 0.752:1 for REV steers and decreased (P < 0.01) approximately 0.002/d from at 1.378 on d 0 to 0.542 on d 378. Empty body weight gain was 2129 g/d during the initial 42 d period and decreased in a linear fashion (P < 0.01) to 1185 g/d at d 378, decreasing in gain 2.5 g/d. Hot carcass weight gain was similar as it decreased from 1479 to 962 g/d in a linear fashion (P < 0.01) across the feeding period, slowing by 1.4 g/d. Empty body moisture weight, EBPW, EBFW, and EBAW increased (P < 0.01) 520, 190, 490, and 80 g/d from d 0-378, all increasing (P ≤ 0.01) in a quadratic fashion. Implanted steers exhibited an increase (P < 0.01) in EBWG and HCWG (1695.5 and 1359 g/d) compared to CON (1457 and 1169 g/d), or a 239 and 190 g/d increase. Implanted steers also contained more (P < 0.01) EBMW, EBPW, and EBAW (+20.7, +8.5, and +3.1 kg) than CON. These results reflect PA, MA, and AA, as REV steers exhibited increased (P < 0.01) tissue accrual by +67.3, +162.3, and +19.1 g/d, respectively, compared to CON. Fat accretion did not differ over time (P = 0.42) and between treatments (P = 0.76). Protein to fat accretion ratio was greater (P < 0.01) in REV (0.48) compared to CON (0.35). Protein to fat accretion ratio also decreased (P < 0.01) across DOF starting at 0.54 on d 0 and ending at 0.39 on d 378. These data indicate that growth-promoting implants alter composition of gain during the finishing period and protein accretion is increasing at a decreasing rate while fat is increasing at an increasing rate
An Electromagnetic Inverse Problem in the Medical Sciences
No full textMost human tissue is heavily comprised of water and ions; which is dispersive of electromagnetic energy. The definitive goal of this research is to make an accurate determination of dielectric constants and conductivity at different given frequencies of living tissue from measurements outside of the human body. Previous studies used tissue samples or probing mechanisms, but these methods to deduce both the dielectric constant and conductivity values are not necessarily reproducible since the sample itself is not in its natural environment. In the future, the overall goal would be to illuminate the human body with a broad-band pulse of electromagnetic radiation. By doing so, one could measure the dielectric constants or conductivities throughout the body by accumulating reflected and/or transmitted signals. Thus may one deductively determine the electrical coefficients through the use of an inverse problem using the incident and scattered fields as a function of position within the body.
The process and technique implemented in this study uses a frequency response function. The inversion process is non-unique unless both the relative permittivity and conductivity are presumed to be differentiable as functions of frequency. The results, as expected, for the dielectric constant are fairly in accord to the true expected value. However, the conductivity values display much variation at the larger ranges of frequency. This implies that the functions lose their authenticity as frequency is increased
Assessment of Labor Recruitment & Retention Challenges in the Cattle Feeding Industry
Get PDFLabor management in the feedyard industry is a primary concern with beef demand growing and a higher percentage of young adults pursuing college and urban careers rather than rural jobs. In this analysis, several labor challenges within the cattle feeding industry are identified and investigated. As immigration policy floats back and forth in the political spectrum, feedyards continue to increase their reliance on immigrant and minority labor because of the decline of the native born American’s interest in feedyard employment. Little research has been done to evaluate the differences between labor recruitment and retention in the cattle feeding industry, especially in Texas, Oklahoma, and New Mexico. This region is responsible for 28% of the nation’s fed cattle production. An assessment of the challenges management and employees face is imperative and warranted.
In order to understand the gaps between the employer and the employee, two survey instruments were designed to create benchmark data regarding employee management as well as attitudes and perceptions of laborers. These surveys were used to understand the industry’s struggles between feedyard general managers and feedyard laborers (any employee subordinate to the general manager). In order to generate the survey instruments, discussions occurred with four regional feedyard managers. In each meeting the managers expressed their concerns and the issues they encounter in recruiting
and retaining employees. Through the interviews, many challenges were discovered that feedyard mangers in the industry currently handle on a day-to-day basis.
Primary data elicited from feedyard general managers and feedyard laborers was evaluated and analyzed using chi-square analyses. Significant differences were discovered among different feedyard structures, sizes, departments, and ethnicities. The demographics, perceptions, and opinions derived from the feedyard work force was then utilized in ordered logit models to better understand the factors which impact not only the satisfaction of an employee, but also the likelihood of promoting this field of employment to their children
Relationship of Race to Perceived Gender Stereotypes
No full textGender and racial stereotyping are well-documented phenomena that may negatively impact the lives of the stereotyped. However, less is known about how gender stereotypes intersect with the race of the person being stereotyped. This study asked 153 undergraduate psychology students to quickly determine whether a set of gender-stereotyped words “go with” a set of photos or a set of phrases representing people and varying on both gender and race; proportion of response agreement was measured. As predicted, responses could not be explained entirely by gender stereotypes. Rather, unique patterns emerged for each gender × race category. Surprisingly, the phrase condition appeared to elicit more associations than the photo condition
Absorption Water Treatment Potential of Crop-Waste Biochar Made by Controlled and Uncontrolled Pyrolysis: An Investigation into Converting Biowaste to Bioresource for the Developing World
Get PDFAll data was collected by our own research group. The adsorption data was conducted by designed shaker experiments which exploited mass balance principles to generate adsorption kinetic and equilibrium curves. All dissolved dye concentrations determined via UV-vis spectroscopy.Access to clean water is an issue that persists in many developing countries. Available water is often polluted from inadequately treated agricultural, industrial, and human wastes. There are many ways to address environmental challenges for polluted water including source water protection, altering the use patterns of water, and treating heavily polluted water sources before they mix with other, cleaner waters. Employing water protection and water treatment strategies in developing world contexts in particular is often challenging due to a lack of financial resources, industrial infrastructure, and technical know-how. One approach to bridge the gap between the developed “well resourced” world and the developing “limited resource” world is to make use of materials readily available, even waste materials, to treat water and minimize solid and hazardous waste generation. Biochar is such an application of this approach. It is a microporous, carbon-rich adsorbent material that can be made from any virtually any kind of waste biomass or other waste organic material. Since many developing world communities are highly agrarian, people in those communities have access to a large amount of crop and animal waste which can be used as biochar feedstock. In our study, we made crop-waste (rice hull, pecan shell, cottonseed) biochar using temperature-controlled pyrolysis in a muffle furnace (MF) reminiscent of the kinds of high technology, high resource process in the developed world. We contrast that with biochars made from a simple and easily built top-lift updraft (TLUD) pyrolysis process that would not be difficult for developing world communities to appropriate in their local context with biomass they have on hand. We looked specifically at the contrasting abilities of these two types of biochar, MF and TLUD, to adsorb cationic and anion colored dyes in water through controlled shaking experiments. Quantitative examination of the amount of dye that can be removed, on different biochar, and at differing pH helped to discern the mechanism of adsorptive interaction on the biochars. We then relate the way the biochar was made, in light of the material from which it was made, to the adsorptive performance we saw in the dyes. These comparisons provide fundamental understanding into the nature of ionic pollutant surface interactions on biochars. This understanding can be used to design treatment processes for industrial, sanitary, storm-, and agricultural wastewater in both developing and developed worlds
Characterizing Monotone Games
No full textWe expect to find necessary and sufficient conditions on the player's payoff functions that guarantee that a game that is not a GSH can be transformed into a GSH.Solution concepts in games of strategic heterogeneity (GSH), which include games of strategic complements (GSC) as a special case, have been shown to possess very useful properties, such as the existence of highest and lowest serially undominated strategies, and the equivalence of the stability of equilibria and dominance solvability. The main result of this paper gives necessary and sufficient conditions for when a very general class of games, referred to as games of mixed heterogeneity (GMH), can be transformed into GSH in such a way so that these properties are preserved, allowing us to draw the same strong conclusions about solution sets in games that are not originally GSH. This is achieved by reversing the orders on the actions spaces of a given subset of players. Our second main result shows, rather surprisingly, that under mild conditions on the underlying ordering of action spaces, the reversal of orders is the only way in which such a transformation can be achieved. Applications to aggregate games, market games, and crime networks are given
WTAMU 2020 Spring Virtual Commencement Program
No full textVideo of the May 2020 virtual commencement ceremony
THE EFFECTS OF CORTICOTROPIN RELEASING HORMONE AND VASOPRESSIN STRESS CHALLENGE DURATION OF BLOOD PARAMETERS AND PERFORMANCE IN GROWING BEEF STEERS
No full textThe objective of this study was to determine the metabolic, hematologic, endocrine, and performance response of beef steers administered different durations of corticotropin releasing hormone (CRH) and vasopressin (VP) as an endocrine stress challenge. Steers (n =30; initial BW= 416 kg ± 19) were used in a randomized complete block design and assigned to 1 of 3 treatments: 1) Control intravenous jugular injection of 3 mL saline daily from d 0 to 3 (n = 10), 2) Acute 0.3 µg/kg of BW CRH (Bachem Ag, Bubendorf, Switzerland) and 1.0 µg/kg of BW arginine VP (Sigma-Aldrich, Co. St. Louis, MO) on d 0, followed by 3 mL of saline on d 1 to 3 (n = 10), or 3) Chronic 0.3 µg/kg of BW of CRH and 1.0 µg/kg of BW VP from d 0 to 3 (n = 10). Whole blood and serum samples were collected at h 0, 24, 48, 72, 144, and 336 for analysis of complete blood count and non-esterified fatty acids (NEFA). Additionally, rectal temperatures and serum samples were collected at h 0, 1, 2, 24, 25, 26, 48, 49, 50, 72, 73, 74, 144, and 336 after administration of CRH and VP for analysis of cortisol, insulin, and blood metabolites. There was a treatment × hour effect (P = 0.003) for total white blood cell count such that chronic had greater concentration than control but was not different from acute at 72 h. Conversely, monocyte concentration was less at h 144 for chronic cattle than both acute and control (treatment × hour interaction; P ≤ 0.01). A treatment × hour interaction (P = 0.03) was observed for lymphocytes but no treatment differences existed within hour. Stress treatments did not affect (P ≥ 0.13) red blood cell count, hemoglobin, hematocrit, mean corpuscular hemoglobin concentration, neutrophils, or neutrophil-to-lymphocyte-ratio. Serum NEFA tended to be lower (P = 0.09) in control cattle compared to those that were stressed. Rectal temperature tended to be greater for both stress treatments relative to control (stress vs. no; P = 0.06). Cortisol was greater for cattle receiving the acute and chronic treatments than control at h 1 and greater for chronic than both acute and control at h 25, 26, 49, 50, 73, and 74 (treatment × hour; P ≤ 0.01). Similarly, there was a treatment × hour interaction (P ≤ 0.01) for serum glucose and serum insulin concentrations where cattle receiving the acute and chronic treatments had greater glucose at h 1 relative to control and cattle receiving chronic had greater glucose at h 25, 49, 50, 73, and 74 than acute and control. Serum insulin concentrations were greater in chronic and acute treatments than control at h 1 and greater for chronic compared to acute and control at h 25, 49, and 73 (treatment × hour P ≤ 0.01). Serum phosphorus was lower for chronic and control vs. acute at h 25, less for chronic than acute at h 26 and 49, and less for chronic than acute and control at h 50, 73, and 74 (treatment × hour interaction; P ≤ 0.01). A treatment × hour interaction (P ≤ 0.01) was also observed for serum potassium (K) where acute and chronic had lower serum K at h 1 and 2 than control and chronic was less than both acute and control cattle at h 24, 25, 26, 49, 50, 73, and 74. Although a treatment × hour interaction (P ≤ 0.01) was noted for blood urea nitrogen (BUN) concentrations, no differences existed within hour. Stress treatments did not affect (P ≥ 0.38) final BW, ADG, DMI, and water intake from d 0 to 21. These results demonstrate that a CRH and VP challenge influences serum glucose, insulin, cortisol, electrolyte, and white blood cell concentrations. When comparing acute vs chronic treatments there were similar response on d 0 as both were administered CRH and VP, but from d 1 to 3 acute was different than chronic. These differences suggest that the chronic continued to respond to the administration of CRH and VP on d 0 to 3. However, CRH and VP challenge demonstrated no effects on beef steer performance parameters of BW, ADG, and DMI suggesting that while there are changes in blood metabolites from the stress model used there was likely not a great enough response elicited to influence performance response
The Impact of Self-Control and Texting-Related Accidents on the Relationship Between Mindfulness and Mobile Texting While Driving Behavior
No full textA version of this paper has already been accepted after peer-review to the Southwestern Association of Business Communication of the Federation of Business Disciplines (FDB) annual conference, San Antonio, TX. Additionally, the revised version of the project will be under review to the Computers in Human Behavior journal by late January 2020. Expected findings: Self-control was a mediator of the relationship between mindfulness and texting while driving behavior. Also, texting-related accidents moderated the relationship between mindfulness and texting while driving. These findings help extend prior correlation research.The safety dangers of texting while driving are well-known in the literature, as such, it is important to understand the relationships between mindfulness, self-control, and texting while driving behavior. Prior research has conducted correlational work among these constructs; however, this study found that acting with awareness and observing were inversely related to texting while driving. This study examined the relationship between mindfulness, self-control, texting-related accidents, and texting while driving. Several findings were illustrated from this study including: 1) mindfulness (awareness and observe) were inversely associated to texting while driving behavior, 2) self-control mediated the inverse relationship between mindfulness and texting while driving behavior, and 3) texting-related accidents moderated the relationship between mindfulness and texting while driving behavior. Data consisted of 608 adult drivers who completed an online questionnaire using the measures of the study. Analyses conducted included correlations, multiple regression, and moderated regression. Findings suggested that self-control showed promise as a possible mediator of the relationship between mindfulness and texting while driving. And, texting-related accidents also moderated the relationship between mindfulness and texting while driving, which informs us of the importance of studying text-related accidents. Implications are also offered to stimulate future research to better understand mindfulness, self-control, and texting while driving behavior
An Examination of Family Cohesion and Self-Esteem as Mediators of Bilingualism and Reading Achievement in Second-Generation Immigrant Students
Get PDFWe found support for a parallel mediation analysis model. We found that increased family cohesion and self-esteem mediated the relationship between bilingualism skills and students' reading achievement scores. Our findings can help educators understand second-generation immigrant students' reading achievement scores.Institutions in higher education have seen a rise in enrollment of second-generation Latino/a immigrant students due to the recent push to recruit more Latino/a students (Arbeit, Staklis, & Horn, 2016). As such, the purpose of the study is to examine family cohesion and self-esteem as possible mediators of the relationship between bilingual dominance and reading achievement. The study included 2,107 second-generation Latino youth participants enrolled in 8th and 9th grade who were born of immigrant parents. Regression and parallel mediation analyses were conducted to examine the study’s hypotheses. Findings revealed that both family cohesion and self-esteem mediated the relationship between bilingualism and reading score. The implications of this study can be used for faculty in K9-10 schools and institutions of higher education