The application of body weight data to performance testing of beef cattle

1964 ◽  
Vol 15 (3) ◽  
pp. 471 ◽  
Author(s):  
RM Seebeck ◽  
DW Campion

A least squares method particularly suited to automatic computation, for calculating adjustments to remove extraneous variation in performance test data, is described. Multiplicative adjustments can be calculated for discontinuous variables, e.g. sex, or for continuous variables, e.g. age at weaning. By calculation of all desired adjustments simultaneously each adjustment factor is as free as possible from the effects of the other variables. Results are given of the application of the technique to weaning weights of stud Hereford and Aberdeen Angus cattle reared on one property. With the use of several different models of analysis, the effects of age of dam, sex, year of birth, age at weaning, sire, and birth weight were investigated and comparisons drawn between the two breeds used, and between this study and other published work. The effect of some of these variables on birth weight is discussed, and the relative effects of some of the variables on weaning weight and birth weight compared. The use of a combination of traits to form a selection index is also discussed.

1995 ◽  
Vol 1995 ◽  
pp. 127-127
Author(s):  
Margaret E King ◽  
P J Broadbent

The selection objective of the SAC Simmental MOET Project, is to improve the economic efficiency of lean, or saleable, meat production in crossbred beef production systems.The factors which contribute to the selection objective are the yield of saleable meat, feed intake and calving difficulty. These goal characteristics are combined into an index by taking into account their respective financial values and costs. Calves generated by multiple ovulation and embryo transfer (MOET) are weaned from their recipient dams at 10 weeks old and placed in performance test from 5 to 11 months of age. At the end of the performance test, saleable meat yield is estimated from liveweight at end of test, ultrasonic fat depth measurements and muscling score. Calving difficulty is predicted from the birthweight and gestation length of the animal on test whilst feed intake is measured directly by recording individual food intakes during performance testing. The estimated breeding value for the selection index of an animal is expressed in £'s (pounds sterling) as deviations from a mean of zero for the SAC population of Simmentals. It is calculated using the information for each animal plus that of all its relatives in its own and other performance tests by means of BLUP procedures.The objective of the work described here was to evaluate the effectiveness of the selection index in identifying sires of superior genetic merit for use in crossbred beef production systems.


Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1340
Author(s):  
Enrico Mancin ◽  
Cristina Sartori ◽  
Nadia Guzzo ◽  
Beniamino Tuliozi ◽  
Roberto Mantovani

Selection in local dual-purpose breeds requires great carefulness because of the need to preserve peculiar traits and also guarantee the positive genetic progress for milk and beef production to maintain economic competitiveness. A specific breeding plan accounting for milk, beef, and functional traits is required by breeders of the Alpine Grey cattle (AG), a local dual-purpose breed of the Italian Alps. Hereditability and genetic correlations among all traits have been analyzed for this purpose. After that, different selection indexes were proposed to identify the most suitable for this breed. Firstly, a genetic parameters analysis was carried out with different datasets. The milk dataset contained 406,918 test day records of milk, protein, and fat yields and somatic cells (expressed as SCS). The beef dataset included performance test data conducted on 749 young bulls. Average daily gain, in vivo estimated carcass yields, and carcass conformation (SEUROP) were the phenotypes obtained from the performance tests. The morphological dataset included 21 linear type evaluations of 11,320 first party cows. Linear type traits were aggregated through factor analysis and three factors were retained, while head typicality (HT) and rear muscularity (RM) were analyzed as single traits. Heritability estimates (h2) for milk traits ranged from 0.125 to 0.219. Analysis of beef traits showed h2 greater than milk traits, ranging from 0.282 to 0.501. Type traits showed a medium value of h2 ranging from 0.238 to 0.374. Regarding genetic correlation, SCS and milk traits were strongly positively correlated. Milk traits had a negative genetic correlation with the factor accounting for udder conformations (−0.40) and with all performance test traits and RM. These latter traits showed also a negative genetic correlation with udder volume (−0.28). The HT and the factor accounting for rear legs traits were not correlated with milk traits, but negatively correlated with beef traits (−0.32 with RM). We argue that the consequence of these results is that the use of the current selection index, which is mainly focused on milk attitude, will lead to a deterioration of all other traits. In this study, we propose more appropriate selection indexes that account for genetic relationships among traits, including functional traits.


Author(s):  
Amir Golalipour ◽  
Varun Veginati ◽  
David J. Mensching

In the asphalt materials community, the most critical research need is centered around a paradigm shift in mixture design from the volumetric process of the previous 20-plus years to an optimization procedure based on laboratory-measured mechanical properties that should lead to an increase in long-term pavement performance. This study is focused on advancing the state of understanding with respect to the value of intermediate temperature cracking tests, which may be included in a balanced mix design. The materials included are plant-mixed, laboratory-compacted specimens reheated from the 2013 Federal Highway Administration’s (FHWA’s) Accelerated Loading Facility (ALF) study on reclaimed asphalt pavement/reclaimed asphalt shingle (RAP/RAS) materials. Six commonly discussed intermediate temperature (cracking and durability) performance testing (i.e., Asphalt Mixture Performance Tester [AMPT] Cyclic Fatigue, Cantabro, Illinois Flexibility Index Test [I-FIT], Indirect Tensile Cracking [ITC, also known as IDEAL-CT], Indirect Tensile Nflex, and Texas Overlay Test) were selected for use in this study based on input from stakeholders. Test results were analyzed to compare differences between the cracking tests. In addition, statistical analyses were conducted to assess the separation among materials (lanes) for each performance test. Cyclic fatigue and IDEAL-CT tests showed the most promising results. The ranking from these two tests’ index parameters matched closely with ALF field performance. Furthermore, both showed reasonable variability of test data and they were successful in differentiating between different materials.


BMJ ◽  
2020 ◽  
pp. m4561
Author(s):  
R A Lewis

AbstractObjectiveTo estimate the daily dietary energy intake for me to maintain a constant body weight. How hard can it be?DesignVery introspective study.SettingAt home. In lockdown. (Except every Tuesday afternoon and Saturday morning, when I went for a run.)ParticipantsMe. n=1.Main outcome measuresMy weight, measured each day.ResultsSleeping, I shed about a kilogram each night (1.07 (SD 0.25) kg). Running 5 km, I shed about half a kilogram (0.57 (SD 0.15) kg). My daily equilibrium energy intake is about 10 000 kJ (10 286 (SD 201) kJ). Every kJ above (or below) 10 000 kJ adds (or subtracts) about 40 mg (35.4 (SD 3.2) mg).ConclusionsBody weight data show persistent variability, even when the screws of control are tightened and tightened.


Author(s):  
Shane E. Powers ◽  
William C. Wood

With the renewed interest in the construction of coal-fired power plants in the United States, there has also been an increased interest in the methodology used to calculate/determine the overall performance of a coal fired power plant. This methodology is detailed in the ASME PTC 46 (1996) Code, which provides an excellent framework for determining the power output and heat rate of coal fired power plants. Unfortunately, the power industry has been slow to adopt this methodology, in part because of the lack of some details in the Code regarding the planning needed to design a performance test program for the determination of coal fired power plant performance. This paper will expand on the ASME PTC 46 (1996) Code by discussing key concepts that need to be addressed when planning an overall plant performance test of a coal fired power plant. The most difficult aspect of calculating coal fired power plant performance is integrating the calculation of boiler performance with the calculation of turbine cycle performance and other balance of plant aspects. If proper planning of the performance test is not performed, the integration of boiler and turbine data will result in a test result that does not accurately reflect the true performance of the overall plant. This planning must start very early in the development of the test program, and be implemented in all stages of the test program design. This paper will address the necessary planning of the test program, including: • Determination of Actual Plant Performance. • Selection of a Test Goal. • Development of the Basic Correction Algorithm. • Designing a Plant Model. • Development of Correction Curves. • Operation of the Power Plant during the Test. All nomenclature in this paper utilizes the ASME PTC 46 definitions for the calculation and correction of plant performance.


Author(s):  
Tomas Gro¨nstedt ◽  
Markus Wallin

Recent work on gas turbine diagnostics based on optimisation techniques advocates two different approaches: 1) Stochastic optimisation, including Genetic Algorithm techniques, for its robustness when optimising objective functions with many local optima and 2) Gradient based methods mainly for their computational efficiency. For smooth and single optimum functions, gradient methods are known to provide superior numerical performance. This paper addresses the key issue for method selection, i.e. whether multiple local optima may occur when the optimisation approach is applied to real engine testing. Two performance test data sets for the RM12 low bypass ratio turbofan engine, powering the Swedish Fighter Gripen, have been analysed. One set of data was recorded during performance testing of a highly degraded engine. This engine has been subjected to Accelerated Mission Testing (AMT) cycles corresponding to more than 4000 hours of run time. The other data set was recorded for a development engine with less than 200 hours of operation. The search for multiple optima was performed starting from more than 100 extreme points. Not a single case of multi-modality was encountered, i.e. one unique solution for each of the two data sets was consistently obtained. The RM12 engine cycle is typical for a modern fighter engine, implying that the obtained results can be transferred to, at least, most low bypass ratio turbofan engines. The paper goes on to describe the numerical difficulties that had to be resolved to obtain efficient and robust performance by the gradient solvers. Ill conditioning and noise may, as illustrated on a model problem, introduce local optima without a correspondence in the gas turbine physics. Numerical methods exploiting the special problem structure represented by a non-linear least squares formulation is given special attention. Finally, a mixed norm allowing for both robustness and numerical efficiency is suggested.


1999 ◽  
Vol 47 (1) ◽  
pp. 123-128 ◽  
Author(s):  
T. Varga ◽  
I. Hlubik ◽  
L. Várnagy ◽  
P. Budai ◽  
E. Molnár

The purpose of this work was to determine the individual and combined effects of insecticide Sumithion 50 EC (50% fenitrothion) and herbicide Fusilade S (12.5% fluazifop-P-butyl) on the development of pheasant embryos. Eggs were treated by injection of various concentrations of pesticides into the air space on day 12 of incubation. Pathological examination of embryos was carried out on day 23 of the hatching period. Mortality rate, body weight data and morphological alterations were evaluated after the macroscopic examination. The skeletal staining method was used to detect deformities. The two pesticides used in combination moderated the toxic/teratogenic effects of individual treatment.


2021 ◽  
Vol 8 (1) ◽  
pp. 59-64
Author(s):  
Almuzakkir . ◽  
Muhammad . ◽  
Adi Setiawan

Fuel is something that is very important in everyday life. Almost every human being needs fuel to meet their needs and support their activities, for example cooking in household needs. Currently, fossil fuels or fuel oil (BBM) are still widely used to meet demand, however, it should be noted that fossil fuels or fuel oil (BBM) are non-renewable natural resources. The biomass rocket stove is one of the modern stove innovations that uses biomass energy as the main energy source. Rocket stoves are designed to increase fuel efficiency with thermal efficiency, a combination of the increased combustion efficiency and heat transfer associated with burning briquette fuel. The purpose of this research is to design and manufacture rocket stove fired with coconut and bamboo biomass for household needs as well as developing methods and equipment for performance testing of rocket stoves. In this study, several steps were carried out, including designing a rocket furnace, selecting biomass fuel and testing the performance of a rocket furnace. From the design of the biomass stove, it is noteworthy that the design with two holes makes the combustion air easily enters and makes combustion in the furnace more perfect and efficient. Water boiling test using three types of solid fuels with the cold start condition suggested that the highest thermal efficiency was coconut fronds with a value of 38% and the lowest thermal efficiency was found from coconut shell combustion, i.e. 22%. During hot start test, the highest thermal efficiency was obtained from coconut fronds firing with a value of 41%. Moreover, with simmer water boiling test method, firing the rocket stove with coconut fronds showed the highest thermal efficiency with a value of 37%. Keywords: Rocket Stoves, Coconut Fronds and Shells, Bamboo, Thermal Efficiency, .Water Boiling Tests.


2014 ◽  
Vol 14 (2) ◽  
pp. 257-270 ◽  
Author(s):  
Magdalena Sobczyńska ◽  
Tadeusz Blicharski ◽  
Mirosław Tyra

Abstract Relationships between performance test traits (growth rate, backfat thickness, loin depth, lean meat percentage, exterior, phenotypic selection index) and longevity traits (length of productive life, number of litters, total number of weaned pigs, number of weaned piglets per year, number of litters per year) in Landrace sows were evaluated using canonical correlation analysis. The data set consisted of 23,012 purebred sows that farrowed from 1994 to 2011 in 161 herds. The first three canonical correlations (0.37, 0.25, 0.07) were highly significant (P<0.0001). Correlations of the first canonical variate with the original measured variables indicated that sows with high values for this variate had lower growth rate (r=-0.31) and loin depth (r=-0.43), greater backfat thickness (r=0.23), as well as being older at birth of their last litter (r=0.98). These sows also had a greater number of litters (r=0.94) and better lifetime efficiency (r=0.61 and r=0.70 for number of weaned piglets per year and number of litters per year, respectively). Canonical loadings for the second canonical function indicate that sows with high values for the second set of variates had high growth rate (r=0.79) and phenotypic selection index (r=0.83), excellent conformation (r=0.62), as well as better efficiency in pig production (r=0.67). The squared multiple correlations show that the first canonical variate of the performance traits is a poor predictor of longevity (0.13) and nearly useless for predicting efficiency traits (0.07). Performance test traits explain 11% of the variance in the variables of longevity and lifetime productivity, whereas dependent variables explain only 3% of the variance in performance test traits. The relationships between performance test data and subsequent lifetime productivity or longevity were significant and unfavourable but low for Polish Landrace population


Author(s):  
Ke Li ◽  
Bo Yu ◽  
Zhaoyao Shi ◽  
Zanhui Shu ◽  
Rui Li

With the development of gears towards high temperature, high pressure, high speed and high stress, gear measurement, in which only the static geometric accuracy is considered, is unable to meet the current application requirements. While, the low precision and single function gear tester constrains the measurement of gear dynamic performance. For the resolution of this problem, based on the principle of gear system dynamics and several precision mechanical design techniques, a gear dynamic testing machine has been developed, providing new instruments for gear testing. On the basis of research of the principle of dynamic performance test, the primary measurement items of the testing machine have been determined. The measuring principles of each item and the driving and loading form of the testing machine have been examined. The measurement and control system of the testing machine and its corresponding software have been developed. The instrument can not only obtain the static precision index of the gear, but also obtain the dynamic performance index of the gear in variable working conditions. According to the actual test, the uncertainty of instrument is 3.8 μm and the external disturbance caused by the shaft vibration is less than 0.6 μm, which can meet the 5–6 grade precision gear testing requirement.


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