scholarly journals Genetic parameters and principal components analysis of breeding value for birth and weaning weight in Egyptian buffalo

2021 ◽  
Vol 34 (1) ◽  
pp. 12-19
Author(s):  
Mohamed Mahmoud Ibrahim Salem ◽  
Amin Mohamed Said Amin ◽  
Ayman Fouad Ashour ◽  
Mohamed Mohamed El-said Ibrahim ◽  
Mohammed Kotb Abo-Ismail
Keyword(s):  
Principal Components Analysis ◽  
Principal Components ◽  
Genetic Parameters ◽  
Growth Traits ◽  
Breeding Value ◽  
Genetic Trend ◽  
Weaning Weight ◽  
Breeding Values ◽  
Factors Affecting ◽  
Components Analysis

Objective: The objectives of the current study were to study the main environmental factors affecting birth weight (BW) and weaning weight (WW), estimate variance components, genetic parameters and genetic trend and to evaluate the variability and relationships among breeding value of BW and WW using principal components analysis (PCA).Methods: A total of 16,370 records were collected from 8,271 buffalo calves. Genetic parameters and breeding values were estimated using a bivariate animal model which includes direct, maternal and permanent maternal effects. These estimates were standardized and used in PCA.Results: The direct heritability estimates were 0.06 and 0.41 for BW and WW, respectively whereas direct maternal heritability values were 0.03 and 0.14, respectively. Proportions of variance due to permanent environmental effects of dam were 0.455 and 0.280 for BW and WW respectively. The genetic correlation between BW and WWs was weak approaching zero, but the maternal correlation was 0.26. The first two principal components (PC1 and PC2) were estimated utilizing the standardized breeding values according to Kaiser method. The total variance explained by the first two PCs was 71.17% in which 45.91% and 25.25% were explained by PC1 and PC2, respectively. The direct breeding values of BW were related to PC2 but those of WW and maternal breeding values of BW and WWs were associated with PC1.Conclusion: The results of genetic parameters and PCA indicate that BW and WWs were not genetically correlated and improving growth traits of Egyptian buffaloes could be achieved using WW without any adverse effect by BW.

scholarly journals Evaluation of Breeding Value Based on Scores Achieved in the Polish Championships for Young Horses

2015 ◽  
Vol 15 (4) ◽  
pp. 879-887
Author(s):  
Tomasz Próchniak ◽  
Iwona Rozempolska-Rucińska ◽  
Grzegorz Zięba ◽  
Marek Łukaszewicz
Keyword(s):  
Genetic Improvement ◽  
Genetic Parameters ◽  
Performance Test ◽  
Breeding Value ◽  
Genetic Trend ◽  
Breeding Values ◽  
Physical Traits ◽  
Young Horses ◽  
Show Jumping ◽  
Detailed Picture

Abstract Genetic improvement of show jumping horses is problematic, given the multitude of physical traits that determine sport usability and the specific mental predispositions required during training and competitions. The Polish Championships for Young Horses (PCYH) provide an opportunity to evaluate usability traits in Polish horses, which, however, is not a basis for evaluation of the breeding value. The aim of the study was to propose a model for evaluation of the breeding value of horses taking part in the Championships. In total, 1232 starts of 894 4-, 5-, 6-, and 7-year-old horses were analysed. Indices of BLUP breeding values were calculated based on 7 traits with known genetic parameters (ranking in the championship, style rating on days 1, 2, and 3, and penalty points on days 1, 2, and 3). A low and irregular genetic trend, significant only in the case of penalties scored on days 1 and 2 of the championships, was shown. Compatibility of the evaluation of the breeding value estimated on the basis of scores achieved in the Polish Championships for Young Horses with the scores of the performance test carried out in Training Centres was shown. It was also demonstrated that the “sum penalty” and “sum style” measured during the three days of the Championships is sufficient for evaluation of the BLUP breeding value. It was suggested that the evaluation combined with the results achieved at the PCYH (in four age categories) would provide a more detailed picture of the genetic predispositions of jumping horses.

scholarly journals Weaning results of beef Hungarian Fleckvieh calves 2. Genetic parameters, breeding values

2010 ◽  
Vol 53 (1) ◽  
pp. 26-36 ◽  
Author(s):  
S. Bene ◽  
I. Füller ◽  
A. Fördős ◽  
F. Szabó
Keyword(s):  
Genetic Parameters ◽  
Correlation Coefficients ◽  
Breeding Value ◽  
Phenotypic Variance ◽  
Weaning Weight ◽  
Breeding Values ◽  
Estimated Breeding Values ◽  
Genetic Value ◽  
Maternal Heritability ◽  
Daily Gain

Abstract. Weaning weight, preweaning daily gain and 205-day weight of Hungarian Fleckvieh calves (n=8 929, bulls =4 539, heifers =4 390) born from 232 sires between 1980 and 2003 were examined. Variance, covariance components and heritability values and correlation coefficients were estimated. The effect of the maternal permanent environment on genetic parameters and breeding values were examined. Two animal models were used for breeding value estimation. The direct heritability (hd2) of weaning weight, preweaning daily gain and 205-day weight was between 0.37 and 0.42. The maternal heritability (hm2) of these traits was 0.06 and 0.07. The direct-maternal correlations (rdm) were medium and negative −0.52 and −0.74. Contribution of the maternal heritability and maternal permanent environment to phenotype is smaller than that of direct heritabilities (hm2+c2< hd2). The ratio of the variance of maternal permanent environment in the phenotypic variance (c2) changed from 3 to 6 %. Estimated breeding values changed whether the permanent environmental effect of dam wasn’t taken into consideration but the rank of the animals was not modified. The genetic value for weaning results of Hungarian Fleckvieh population has increased since 1997.

scholarly journals Maternal and direct genetic parameters for tail length, tail lesions and growth traits in pigs

2020 ◽  
Author(s):  
Sheila Aikins-Wilson ◽  
Mehdi Bohlouly ◽  
Sven König
Keyword(s):  
Maternal Effects ◽  
Genetic Parameters ◽  
Growth Traits ◽  
Tail Length ◽  
Breeding Value ◽  
Research Station ◽  
Weaning Weight ◽  
Tail Biting ◽  
Breeding Goal ◽  
Positive Direct

Abstract Tail length and tail lesions are major trigger for tail biting in pigs. Against this background, two datasets were analyzed to estimate genetic parameters for tail characteristics and growth traits. Dataset 1 considered measurements for trait tail length (T-LEN) and for the growth traits birth weight (BW), weaning weight (WW), post weaning weight (PWW) and average daily gain (ADG) from 9,348 piglets. Piglets were born in the period from 2015 to 2018, and kept on the university Gießen research station. Dataset 2 included 4,943 binary observations from 1,648 pigs from the birth years 2016 to 2019 for tail lesions (T-LES) as indicators for nail necrosis, tail abnormalities or tail biting. Tail lesions were recorded at 30 ± 7 days after entry for rearing (T-Les-1), at 50 ± 7 days after entry for rearing (end of rearing period, T-LES-2), and 130 ± 20 days after entry for rearing (end of fattening period, T-LES-3). Genetic statistical model evaluation for dataset 1 based on Akaike’s information criterion and likelihood ration tests suggested multiple-trait animal models considering covariances between direct and maternal genetic effects. The direct heritability for T-LEN was 0.42 (±0.03), indicating the potential for genetic selection on short tails. The maternal genetic heritability for T-LEN was 0.05 (±0.04), indicating influence of uterine characteristics on morphological traits. The negative correlation between direct and maternal effects for T-LEN of -0.35 (±0.13), as well as the antagonistic relationships (i.e., positive direct genetic correlations in the range from 0.03 to 0.40) between T-LEN with the growth traits BW, WW, PWW and ADG, complicate selection strategies and breeding goal definitions. The correlations between direct effects for T-LEN and maternal effects for breeding goal traits, and vice versa, were positive, but associated with quite large SE. The heritability for T-LES when considering the three repeated measurements was 0.23 (±0.04) from the linear (repeatability of 0.30) and 0.21 (±0.06) (repeatability of 0.29) from the threshold model. The breeding value correlations between T-LES-3 with breeding values from the repeatability models were quite large (0.74 – 0.90), suggesting trait lesion recording at the end of the rearing period. To understand all genetic mechanisms in detail, ongoing studies are focusing on association analyses between T-LEN and T-LES, and the identification of tail biting from an actor’s perspective.

scholarly journals Relationship between direct and maternal genetic effects on weaning weight of Limousin and crossbred beef calves

2021 ◽  
Author(s):  
Ferenc Szabó ◽  
Judit Márton ◽  
Eszeter Szabó ◽  
Márton Szűcs ◽  
Szabolcs Bene
Keyword(s):  
Population Genetic ◽  
Genetic Parameters ◽  
Rank Correlation ◽  
Correlation Coefficients ◽  
Breeding Value ◽  
Genetic Trend ◽  
Weaning Weight ◽  
Value Estimation ◽  
Population Genetic Parameters ◽  
Maternal Heritability

Population genetic parameters, direct and maternal breeding value, the genetic trend in the weaning weight of Limousin beef cattle calves were estimated in the period 1992–2019. Data of 19 764 calves (15 437 purebred Limousin and 4 327 crossbred) were computed. Crossbred calves were sired by Limousin breeding bulls from Simmental dams. Calves in question came from 37 herds and from 240 sires in Hungary. DFREML and MTDFREML software was used for the estimation of population genetic parameters, BLUP animal model for breeding value estimation. Weighted linear regression model was used for describing genetic trends. The maternal heritability (h<sup>2</sup><sub>m</sub> ± SE = 0.29 ± 0.03; 0.32 ± 0.10) was approximately half of the direct heritability (h<sup>2</sup><sub>d</sub> ± SE = 0.63 ± 0.05; 0.68 ± 0.12). The direct maternal covariance is negative, the direct maternal genetic correlation coefficients (r<sub>dm</sub> ± SE = –0.80 ± 0.03 and –0.96 ± 0.07) are strong negative. The Spearman rank correlation between direct and maternal breeding value in purebred population is moderate and negative (r<sub>rank</sub> = –0.33; P &lt; 0.01), in crossbred population it is strong and negative (r<sub>rank</sub> = –0.99; P &lt; 0.01). According to direct and maternal breeding values of sires, the genetic trend of the weaning weight of purebred and crossbred Limousin calves appeared stagnant during the examined period (b = +0.01 kg/year to +0.19 kg/year). Keywords: d

Diagnoses Generated by Numerical Taxonomic Methods Applied to Standard Blood Variables

1980 ◽  
Vol 19 (04) ◽  
pp. 205-209
Author(s):  
L. A. Abbott ◽  
J. B. Mitton
Keyword(s):  
Liver Cirrhosis ◽  
Renal Disease ◽  
Principal Components Analysis ◽  
Discriminant Function ◽  
Principal Components ◽  
Discriminant Function Analysis ◽  
Chronic Renal Disease ◽  
Function Analysis ◽  
Infectious Hepatitis ◽  
Components Analysis

Data taken from the blood of 262 patients diagnosed for malabsorption, elective cholecystectomy, acute cholecystitis, infectious hepatitis, liver cirrhosis, or chronic renal disease were analyzed with three numerical taxonomy (NT) methods : cluster analysis, principal components analysis, and discriminant function analysis. Principal components analysis revealed discrete clusters of patients suffering from chronic renal disease, liver cirrhosis, and infectious hepatitis, which could be displayed by NT clustering as well as by plotting, but other disease groups were poorly defined. Sharper resolution of the same disease groups was attained by discriminant function analysis.

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