Degree of connectedness among groups of centrally tested beef bulls

2004 ◽  
Vol 84 (1) ◽  
pp. 37-47 ◽  
Author(s):  
V. M. Roso ◽  
F. S. Schenkel ◽  
S. P. Miller

The degree of connectedness among test groups (TG) of bulls tested in central evaluation stations from 1988 to 2000 in Ontario, Canada, was evaluated using the following methods: average prediction error variance of the difference between estimated breeding values (PEVD), variance of estimated differences between test group effects (VED), connectedness rating (CR), and total number of direct genetic links between test groups (GLT). The model used in the analysis included the effects of breed and TG (fixed) and animal (random). PEVD was assumed the most adequate measure of connectedness and results from the alternative methods VED, CR, and GLT were compared against it. Models to predict the average PEVD of pairs of TG and the average PEVD of each TG with all other TG on the basis of VED, CR, and GLT were developed. Results from all measures of connectedness indicated an unfavorable trend in the degree of connectedness after 1994. The average PEVD of pairs of TG can be better predicted on the basis of the model that includes GLT. The average PEVD of each TG with all other TG can be better predicted on the basis of models that include either CR or GLT. Connectedness among TG of centrally tested beef bulls can be adequately assessed for specific pairs of TG or overall for each TG with all other TG using GLT. Key words: Accuracy, central test, genetic evaluation, harmonic mean

2000 ◽  
Vol 80 (1) ◽  
pp. 19-24 ◽  
Author(s):  
P. K. Charagu ◽  
D. H. Crews Jr. ◽  
R. A. Kemp ◽  
P. B. Mwansa

Pre-slaughter ultrasound and carcass measurements of ribeye area (REA) and backfat (FAT) were recorded on composite beef bulls (n = 60), heifers (n = 60) and steers (n = 60). Breed composition of the composite was: 0.44 British (Hereford, Angus and Shorthorn) 0.25 Charolais, 0.25 Simmental and 0.06 Limousin. The Aloka SSD-1100 (AL) and the Tokyo Keiki CS 3000 (TK) ultrasound machines were compared by evaluating the difference between ultrasound and carcass measurements (bias), and the standard error of prediction (SEP). AL under-predicted REA in all three sexes while TK overpredicted heifers and steers and underpredicted bulls. Both machines were similar in accuracy among bulls for REA. For FAT AL underpredicted all three sexes while TK underpredicted heifers and had very small bias for bulls and steers. SEP for FAT were similar for both machines. Both machines underpredicted REA in larger muscled cattle and overpredicted in smaller-muscled cattle. Both machines also underpredicted FAT in fatter animals and overpredicted FAT in leaner animals. Machines were similar in accuracy among cattle with larger REA but differed significantly (P < 0.05) among smaller-muscled cattle. Machines were comparable in accuracy among animals of all FAT sizes. This study demonstrates that there is an important relationship between machine and the size and depth of muscle and backfat, respectively, and consequently between machine and sex, in accuracy of ultrasound prediction. Key words: Beef cattle, ultrasound, accuracy, back fat, ribeye area


1987 ◽  
Vol 67 (4) ◽  
pp. 985-990 ◽  
Author(s):  
C. SMITH ◽  
J. RUANE

Groups of sibs, sisters to bulls being bred for progeny testing, can be produced by multiple ovulation and embryo transfer (MOET). Sib tests are complete at 3 yr of age, and progeny tests when bulls are about 5.5–6 yr of age. The merit of commercial semen could be increased by using the bulls with the highest estimated breeding values from both the sib test group and the progeny test group rather than only from the latter. With current selection rates (20%) among progeny-tested bulls for commercial use, current genetic trend (0.1 SD units per year) in bulls and with the equivalent of 3–7 full sisters per bull, the relative genetic superiority of semen from the combined groups could be from 1.10 to 1.20 times that from the progeny-tested group alone. Key words: Embryo transfer, sib testing, progeny testing, commercial semen


1999 ◽  
Vol 1999 ◽  
pp. 121-121 ◽  
Author(s):  
R. M. Lewis ◽  
R. E. Crump ◽  
G. Simm ◽  
R. Thompson

With across-flock genetic evaluations, the extent of genetic links or connectedness between animals in separate flocks affects the reliability of selection decisions. As connectedness improves, error in comparing breeding values among flocks falls. Connectedness is thought more important when founder animals (i.e. unknown parentage) of separate flocks differ genetically. The prediction error variance (PEV) of differences in estimated breeding values (EBV) between animals is considered an appropriate measure of connectedness (Kennedy and Trus, 1993). In this study the level of connectedness, and its consequence, in breeding schemes that differ in the extent of ancestral relationships between flocks, and in which founder animals of these flocks differ genetically, was assessed by stochastic simulation.


1988 ◽  
Vol 68 (1) ◽  
pp. 49-56 ◽  
Author(s):  
E. P. de ROSE ◽  
J. W. WILTON

Data collected from Canadian central test stations were used to obtain estimates of genetic progress for test station average daily gain (ADG-T), height at hooks (HH), ultrasonically measured backfat thickness midway between the 11th and 12th ribs (FAT) and scrotal circumference (SC). Where possible, records for preweaning average daily gain (ADG-W) from the Federal-Provincial Herd Record of Performance program were obtained for tested bulls. Estimated breeding values were regressed on year of birth to obtain estimates of genetic trend for each trait, for the six principal breeds enrolled in the testing program: Aberdeen Angus (AA), Charolais (CH), Hereford (HE), Limousin (LM), Shorthorn (SH) and Simmental (SM). Estimated trends were generally significant with the exception of those for the LM breed, and the trait of SC. For FAT, trends were generally positive for the exotic breeds, and negative for the British breeds. Significant positive trends were observed for HH, ADG-W and ADG-T for most breeds. Examples of estimated genetic trends, for the HE breed, were 0.0022 kg d−1 yr−1, 0.0023 kg d−1 yr−1, 0.090 cm yr−1 (NS), − 0.029 mm yr−1, and 0.009 cm yr−1 (NS), respectively, for ADG-W, ADG-T, HH, FAT and SC (NS = not significant). Most estimated trends were low, in the order of 0.1 to 0.5% of population mean per year. Key words: Genetic trend, central test stations, beef bulls


2020 ◽  
Vol 53 (2) ◽  
pp. 1108-1113
Author(s):  
Magnus Malmström ◽  
Isaac Skog ◽  
Daniel Axehill ◽  
Fredrik Gustafsson

Author(s):  
Magdalena Kwiatosz-Muc ◽  
Bożena Kopacz

Background: An increasing number of patients included in home mechanical ventilation (HMV) care has been under observation for many years. The study aimed to assess the patients opinion concerning the expected and perceived quality of care in an HMV system and a patient’s satisfaction with care. Methods: In 2017, patients treated with HMV were surveyed in Poland with the modified SERVQUAL questionnaire. Results: One hundred correctly completed surveys were analyzed. Patient Satisfaction Index was high. In every examined area, the expectations were statistically significant larger than the perception of the services. The biggest gap was in the tangibility dimension and the smallest gap was in the empathy dimension. Perceived respect and understanding for a patient’s needs are close to the expectations. Conclusions: The level of satisfaction with health care among patients treated with HMV in majority of investigated components is high. Moreover, the difference between perceived and expected quality of health care in the HMV system was relatively small in the opinion of the patients themselves. Further investigations with alternative methods are needed.


2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Xiangyu Fan ◽  
Fenglin Xu ◽  
Lin Chen ◽  
Qiao Chen ◽  
Zhiwei Liu ◽  
...  

The compressive strength of shale is a comprehensive index for evaluating the shale strength, which is linked to shale well borehole stability. Based on correlation analysis between factors (confining stress, height/diameter ratio, bedding angle, and porosity) and shale compressive strength (Longmaxi Shale in Sichuan Basin, China), we develop a dimension analysis-based model for prediction of shale compressive strength. A nonlinear-regression model is used for comparison. A multitraining method is used to achieve reliability of model prediction. The results show that, compared to a multi-nonlinear-regression model (average prediction error = 19.5%), the average prediction error of the dimension analysis-based model is 19.2%. More importantly, our dimension analysis-based model needs to determine only one parameter, whereas the multi-nonlinear-regression model needs to determine five. In addition, sensitivity analysis shows that height/diameter ratio has greater sensitivity to compressive strength than other factors.


2021 ◽  
Vol 15 (3) ◽  
pp. 68-71
Author(s):  
Solmaz Həşim qızı Ələsgərova ◽  

The English playwright Harold Pinter's plays "The Guardian" and "The Dwarfs" chosen from his drama are addressed to. The "chaotic world" observed in the plot of the plays is analyzed and the conclusion that the heroes are born of conflict in their relationships is defended. The object of research is to take into account the difference between the consciousness and reality. Issues such as conflicts of mind, aimlessness, phobias, the virtual world, lack of communication, psychological disorders of the personality are examined. As in Pinter's works, you can see the features of realism, romanticism, modernism, postmodernism, symbolism, surrealism, absurdism in the drama of Elchin, Kamal Abdulla and Firuz Mustafa. It is important to compare the Azerbaijani and English drama, which does not fit into the framework of any literary trend and is relevant as it lags behind time, in terms of plot, motives and artistic features. Key words: dramaturgy, fears and phobias, fantasy, loneliness and aggression,“madness”


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