scholarly journals Schätzung genetischer Parameter für Landschafrassen

2004 ◽  
Vol 47 (4) ◽  
pp. 351-358
Author(s):  
F. De Vries ◽  
H. Hamann ◽  
O. Distl
Keyword(s):  
Muscle Mass ◽  
Fixed Effects ◽  
Genetic Correlations ◽  
Lower Saxony ◽  
Sheep Breeds ◽  
Performance Traits ◽  
Wool Quality ◽  
Variance And Covariance Components ◽  
Analysis Of Performance ◽  
Mass Type

Abstract. Title of the paper: Estimation of genetic parameters in land sheep breeds The objective of the present study was a genetic statistical analysis of performance traits recorded at the day of licensing in land sheep breeds. The performance traits score for muscle mass, type and wool quality were analysed for the breeds German Polled Heath, German Grey Heath, Bentheim, German White Heath and Coburg from breeding regions in Lower Saxony and Westphalia. Systematic fixed effects of herd-year-season, test day, sex, birth rearing type and the linear covariate age at licensing were included in the statistical models to estimate the variance and covariance components. There were high additive genetic correlations between muscle mass and type. The estimates of additive genetic correlations between wool quality and type or wool quality and muscle mass were moderate. The heritabilities estimated separately for each breed ranged between h2 = 0.06 and h2 = 0.16 for muscle mass and between h2 = 0.04 and h2 = 0.09 for type. The biggest range of heritabilities was estimated for wool quality with h2 = 0.03 to h2 = 0.14.

scholarly journals Schätzung genetischer Parameter für Testtagsergebnisse von Milchleistungsmerkmalen bei Bunten Deutschen Edelziegen

2004 ◽  
Vol 47 (2) ◽  
pp. 193-202
Author(s):  
D. Bömkes ◽  
H. Hamann ◽  
O. Distl
Keyword(s):  
Protein Content ◽  
Milk Yield ◽  
Milk Fat ◽  
Genetic Parameters ◽  
Genetic Correlations ◽  
Protein Yield ◽  
Lower Saxony ◽  
Genetic Progress ◽  
Performance Traits ◽  
Milk Performance

Abstract. Title of the paper: Estimation of genetic parameters for test day records of milk performance traits in German Improved Fawn The objectives of this study were to estimate genetic parameters for milk performance traits of German Improved Fawn by using univariate und multivariate animal models. The analysis was based on 27,778 test day records of 1,848 German Improved Fawn with 3,574 lactation records distributed over 229 flocks in Lower Saxony, Saxony and Baden-Wuerttemberg. Milk records were sampled between 1988 and 2002. The animals in our analysis were the progeny of 455 sires and 1.148 does. Heritabilities estimated with a multivariate test day model with fixed regression were h2 = 0.19, 0.16 and 0.15 for milk, fat and protein yield. For fat and protein content and Somatic Cell Score (SCS) heritabilities were h2 = 0.17, 0.14 and 0.16, respectively. The additive genetic correlations between milk yield and fat as well as protein yield of German Improved Fawn were very high and positive (rg = 0.84 and rg = 0.77). Milk yield and milk contents were genetically negative correlated with rg = −0.28 for fat and rg = −0.22 for protein content. A moderate additive genetic correlation (rg = 0.48) between fat and protein content was estimated. There were no considerable additive genetic correlations between fat yield and protein content as well as between fat content and protein yield (rg = 0.05 and rg = 0.09). Additive genetic correlations between milk, fat or protein yield and SCS were high and negative, whereas additive genetic correlations between fat or protein content and SCS were low and positive. The genetic parameters estimated from field test records allow to achieve genetic progress in milk performance traits of German Improved Fawn.

scholarly journals ÉTUDE SUR LES PORCS DE RACE CONTRÔLÉS À LA FERME AU QUÉBEC. 2. ESTIMATION DES PARAMÈTRES GÉNÉTIQUES ET PHÉNOTYPIQUES

1988 ◽  
Vol 68 (4) ◽  
pp. 1063-1068 ◽  
Author(s):  
YVAN SAVOIE ◽  
FRANCIS MINVIELLE
Keyword(s):  
Fixed Effects ◽  
Mixed Model ◽  
Growth Traits ◽  
Genetic Correlations ◽  
Growth Index ◽  
Minimum Variance ◽  
Unbiased Estimation ◽  
Parity Number ◽  
Variance And Covariance Components ◽  
Daily Gain

Variance and covariance components were estimated from 94 161 observations of growth and backfat taken on purebred pigs born from 8561 sows and 1431 boars. The mixed model used had herd, year-season, parents' birth years, gender and parity number as fixed effects and sire and dam as random effects. Each breed, Yorkshire, Landrace, Hampshire and Duroc, was studied separately. Several statistical methods of estimation were used but resulting values of heritability were generally quite similar. Heritability of growth traits obtained from MIVQUEO (minimum variance quadratic unbiased estimation) was between 0.21 and 0.40, depending on the breed. Heritability of backfat depth was larger, from 0.49 to 0.77. Genetic correlation of daily gain and backfat varied between 0.08 and 0.56; it was between −0.09 and −0.56 for age at 90 kg and backfat. Corresponding phenotypic correlations were smaller in absolute value but had the same sign as genetic correlations. Key words: Pigs, heritabilities, correlations, backfat, growth, index

scholarly journals Relationship between age at first start and racing performance in Polish Thoroughbreds and Arab horses

2010 ◽  
Vol 53 (6) ◽  
pp. 639-649
Author(s):  
M. Sobczynska
Keyword(s):  
Animal Model ◽  
Maximum Likelihood ◽  
Fixed Effects ◽  
Genetic Correlations ◽  
Point Of View ◽  
Square Root ◽  
Month Of Birth ◽  
Racing Performance ◽  
Performance Traits ◽  
And Performance

Abstract. Genetic and phenotypic parameters for age at first start (AFS) and performance traits were estimated for Polish Thoroughbred and Arab horses using restricted maximum likelihood (REML) with an animal model. The traits representing a horse’s racing performance were log of earnings (EA) and square root of number of starts (NS). Separate analyses per first racing season and whole career were carried out. The first racing season comprised 1 759 Thoroughbreds and 1 026 Arab horses. The racing results of whole racing career were available for 1 319 Thoroughbreds and 815 Arab horses. The model accounted for fixed effects of birth year, month of birth, sex and trainer. The average of AFS of Thoroughbreds was 933.2 days for first racing season and 935.1 for whole career. The same AFS was observed at first season and whole career (about 1 199 days) in Arab horses. Heritability estimates for AFS were rather low (0.15-0.21) . All genetic correlations for Arab horses between age and performance traits varied from moderate to high (from −0.25 to −0.85). For whole career of Thoroughbreds, the genetic correlations had opposite signs compared to those observed in Arabs. Genetic correlation between AFS and EA in first racing season was very low in Thoroughbreds (−0.07), whereas high between AFS and NS (−1); the corresponding values for Arab horses were −0.25 and −0.76. The opposite signs of phenotypic and genetic correlations (0.16 vs −1 and −0.24 vs 1 in first season and whole career, respectively) between AFS and NS in Thoroughbreds were observed. Phenotypic correlations between AFS and performance traits were close to zero for whole career while were rather low and moderate (−0.22 and −0.37) for first season in Arab horses. Delay of the first start of Thoroughbreds is favourable from the point of view of future racing performance in whole career and has no effect on earnings in the first racing season. Arab horses beginning their career at a young age are start frequently and earn more money then those beginning their career later.

scholarly journals Estimates of genetic parameters for growth traits of local Hamra breed threatened with extinction in southwestern arid rangeland of Algeria

2018 ◽  
Vol 34 (4) ◽  
pp. 433-441
Author(s):  
Houari Yerou ◽  
Hakim Ouldouelhadj ◽  
Abdelrahmane Berber ◽  
Amine Mokadem ◽  
Bachir Koudad
Keyword(s):  
Animal Models ◽  
Data Base ◽  
Fixed Effects ◽  
Genetic Parameters ◽  
Growth Traits ◽  
Genetic Correlations ◽  
Phenotypic Correlations ◽  
Body Weights ◽  
Covariance Components ◽  
Variance And Covariance Components

The data base for body weights and growths of 411 Hamra lambs were used to estimate genetic parameters. These lambs were obtained from 31 rams and 493 ewes between 2012 and 2017. Traits analysed were weights at birth (BW), 30 days (W30), 90 days (W90) of age, and average daily gains from 10 to 30 (ADG10-30) and30-90 (ADG30-90) days. REML estimates of variance and covariance components were obtained assuming animal models that included the fixed effects for year-type of birth (2012 single, 2012 twin, . ., 2017 single, 2017 twin), sex (male, female), and ewes age at lambing (< 18, 18-30, 30-42, 42-54, >54 months). Heritabilities were 0.12, 0.06 and 0.11 respectively for BW, W3Oand W90and the average daily gains were 0.05 and 0.17 for ADG0-30and ADG30-90. The estimates of genetic correlations showed no genetic antagonisms among the growth traits. The genetic correlations estimated were positive and medium to high, except those between ADG30-90 and ADG0-30 and between ADG30-90 and W30 which were slightly negative. Phenotypic correlations were positive and ranged from 0.12 to 0.85. They were high between adjacent weights and between ADG and their corresponding weights.

Estimates of genetic parameters for milk and fat yield for the first three lactations in British Friesian cows

1984 ◽  
Vol 38 (3) ◽  
pp. 313-322 ◽  
Author(s):  
Karin Meyer
Keyword(s):  
Milk Yield ◽  
Fixed Effects ◽  
Mixed Model ◽  
Genetic Correlations ◽  
Data Sets ◽  
Lactation Length ◽  
Maximum Likelihood Procedure ◽  
Fat Yield ◽  
Variance And Covariance Components ◽  
Estimate Variance

ABSTRACTA multivariate restricted maximum-likelihood procedure was used to estimate variance and covariance components between and within sires. This method, which considered all lactations simultaneously, accounted for the bias in later lactation records due to selection on dairy performance. Analysis was carried out for a mixed model with herd-year-seasons as fixed and sires as random effects, and fitting lactation length, calving age and month within season of calving as covariables. The data included 26 176 first, 19 978 second and 14 868 third lactation records for 679 test sires, and were analysed in 13 subsets. Additional records for proven sires, treated as fixed effects, were included to improve the data structure.Estimates for all components were higher in later than in earlier data sets, probably, to a large extent, because of a scale effect. Pooled estimates of heritabilities for lactations 1 to 3 were 0·28, 0·19 and 0·24 for milk yield, and 0·27, 0·21 and 0·25 for fat yield. Genetic correlations of 0·91, 0·91 and 0·95 for milk yield, and 0·91, 0·91 and 0·99 for fat yield, were found between lactations 1 and 2, 1 and 3, and 2 and 3, respectively. Results suggest that dairy performance in all lactations is almost identical genetically.

scholarly journals Bayesian inference of genetic parameters for reproductive and performance traits in White Leghorn hens

2018 ◽  
Vol 63 (No. 6) ◽  
pp. 230-236 ◽  
Author(s):  
J.O. Rosa ◽  
G.C. Venturini ◽  
T.C.S. Chud ◽  
B.C. Pires ◽  
M.E. Buzanskas ◽  
...  
Keyword(s):  
Bayesian Inference ◽  
Fixed Effects ◽  
Egg Production ◽  
Genetic Parameters ◽  
Laying Hens ◽  
Reproductive Traits ◽  
A Posteriori ◽  
White Leghorn ◽  
Performance Traits ◽  
And Performance

This study estimated the genetic parameters for reproductive and performance traits and determined which ones can be used as selection criteria for egg production in laying hens using the Bayesian inference. The data of 1894 animals from three generations of White Leghorn laying hens were analyzed for fertility (FERT), hatchability (HATC), and birth rate measurements at 60 weeks of age (BIRTH), body weight at 16 and 60 weeks of age (BW16 and BW60), age at sexual maturity (ASM), egg height/width ratio, weight, and density at 28, 36, and 40 weeks of age (RHW28, RHW36, RHW40, WEGG28, WEGG36, WEGG40, DENS28, DENS36, and DENS40, respectively) traits. The genetic parameters were estimated by the Bayesian inference method of multi-trait animal model. The model included the additive and residual genetic random effects and the fixed effects of generation. The a posteriori mean distributions of the heritability estimates for reproductive traits ranged from 0.14 ± 0.003 (HATC) to 0.22 ± 0.005 (FERT) and performance from 0.07 ± 0.001 (RHW28) to 0.42 ± 0.001 (WEGG40). The a posteriori mean distributions of the genetic correlation between reproductive traits ranged from 0.18 ± 0.026 (FERT and HACT) to 0.79 ± 0.007 (FERT and BIRTH) and those related to performance ranged from –0.49 ± 0.001 (WEGG36 and DENS36) to 0.75 ± 0.003 (DENS28 and DENS36). Reproductive and performance traits showed enough additive genetic variability to respond to selection, except for RHW28. This trait alone would have little impact on the genetic gain because environmental factors would have a higher impact compared to those from the additive genetic factors. Based on the results of this study, the selection applied on the BIRTH trait can be indicated to improve FERT and HATC of eggs. Furthermore, the use of the WEGG40 could improve egg quality in this population.

scholarly journals Genomic Breeding Values for Claw Diseases/Disorders in Czech Holstein Cows

2019 ◽  
Vol 67 (5) ◽  
pp. 1245-1251
Author(s):  
Ludmila Zavadilová ◽  
Eva Kašná ◽  
Zuzana Krupová
Keyword(s):  
Infectious Diseases ◽  
Fixed Effects ◽  
Genetic Correlations ◽  
Genetic Effect ◽  
Holstein Cows ◽  
Additive Genetic Effect ◽  
Genomic Information ◽  
White Line ◽  
Genomic Breeding ◽  
Breeding Values

Genomic breeding values (GEBV) were predicted for claw diseases/disorders in Holstein cows. The data sets included 6,498, 6,641 and 16,208 cows for the three groups of analysed disorders. The analysed traits were infectious diseases (ID), including digital and interdigital dermatitis and interdigital phlegmon, and non-infectious diseases (NID), including ulcers, white line disease, horn fissures, and double sole and overall claw disease (OCD), comprising all recorded disorders. Claw diseases/disorders were defined as 0/1 occurrence per lactation. Linear animal models were employed for prediction of conventional breeding values (BV) and genomic breeding values (GEBV), including the random additive genetic effect of animal and the permanent environmental effect of cow and fixed effects of parity, herd, year and month of calving. Both high and intermediate weights (80% and 50%, respectively) of genomic information were employed for GEBV50 and GEBV80 prediction. The estimated heritability for ID was 3.47%, whereas that for NID 4.61% and for OCD was 2.29%. Approximate genetic correlations among claw diseases/disorders traits ranged from 19% (ID x NID) to 81% (NID x OCD). The correlations between predicted BV and GEBV50 (84–99%) were higher than those between BV and GEBV80 (70–98%). Reliability of breeding values was low for each claw disease/disorder (on average, 3.7 to 14.8%) and increased with the weight of genomic information employed.

scholarly journals PSVIII-38 Late-Breaking Abstract: Estimating genetic parameters of feed efficiency traits in American mink

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 347-347
Author(s):  
Pourya Davoudi ◽  
Duy Ngoc Do ◽  
Guoyu Hu ◽  
Siavash Salek Ardestani ◽  
Younes Miar
Keyword(s):  
Body Weight ◽  
Genetic Correlation ◽  
Feed Intake ◽  
Feed Efficiency ◽  
Fixed Effects ◽  
Genetic Parameters ◽  
American Mink ◽  
Genetic Correlations ◽  
Final Body Weight ◽  
Selection For

Abstract Feed cost is the major input cost in the mink industry and thus improvement of feed efficiency through selection for high feed efficient mink is necessary for the mink farmers. The objective of this study was to estimate the heritability, phenotypic and genetic correlations for different feed efficiency measures, including final body weight (FBW), daily feed intake (DFI), average daily gain (ADG), feed conversion ratio (FCR) and residual feed intake (RFI). For this purpose, 1,088 American mink from the Canadian Center for Fur Animal Research at Dalhousie Faculty of Agriculture were recorded for daily feed intake and body weight from August 1 to November 14 in 2018 and 2019. The univariate models were used to test the significance of sex, birth year and color as fixed effects, and dam as a random effect. Genetic parameters were estimated via bivariate models using ASReml-R version 4. Estimates of heritabilities (±SE) were 0.41±0.10, 0.37±0.11, 0.33±0.14, 0.24±0.09 and 0.22±0.09 for FBW, DFI, ADG, FCR and RFI, respectively. The genetic correlation (±SE) was moderate to high between FCR and RFI (0.68±0.15) and between FCR and ADG (-0.86±0.06). In addition, RFI had low non-significant (P &gt; 0.05) genetic correlations with ADG (0.04 ± 0.26) and BW (0.16 ± 0.24) but significant (P &lt; 0.05) high genetic correlation with DFI (0.74 ± 0.11) indicating that selection for lower RFI will reduce feed intake without adverse effects on the animal size and growth rate. The results suggested that RFI can be implemented in genetic/genomic selection programs to reduce feed intake in the mink production system.

18 Genetic and Phenotypic Parameters for Aleutian Disease Tests and Their Correlations with Pelt Quality, Reproductive Performance, Packed-cell Volume, and Harvest Length in Mink

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 8-9
Author(s):  
Guoyu Hu ◽  
Duy Ngoc Do ◽  
Karim Karimi ◽  
Younes Miar
Keyword(s):  
Cell Volume ◽  
Reproductive Performance ◽  
Packed Cell Volume ◽  
Fixed Effects ◽  
Complex Disease ◽  
Genetic Correlations ◽  
Study Data ◽  
Economic Losses ◽  
Enzyme Linked Immunosorbent Assay ◽  
Selection Of

Abstract Aleutian disease (AD) is an untreatable immune complex disease in mink and brings tremendous economic losses to the mink industry globally. The ineffectiveness of culling, immunoprophylaxis, and medical treatment in controlling AD have urged mink farmers to select AD-resilient mink based on the AD tests. However, the genetic analysis of these tests and their correlations with AD-resilient traits have not been investigated. In this study, data on 5,824 mink were used to estimate the genetic and phenotypic parameters of four AD tests, including two systems of enzyme-linked immunosorbent assay (ELISA), counterimmunoelectrophoresis (CIEP), and iodine agglutination test (IAT), and their genetic and phenotypic correlations with pelt quality, reproductive performance, packed-cell volume (PCV), and harvest length (HL). Significance (P &lt; 0.05) of fixed effects (sex, year, color type, the number of mating, and dam age), covariates (age at blood sampling and age at harvest), and random effects (additive genetic, permanent environmental, and maternal effects) were determined using univariate models. The genetic and phenotypic parameters for all traits were estimated under bivariate models using ASReml 4.1. Estimated heritabilities (±SE) were 0.39±0.05, 0.61±0.07, 0.11±0.07, and 0.26±0.05 for antigen-based ELISA (ELISA-G), virus capsid protein-based ELISA, CIEP, and IAT, respectively. The ELISA-G showed moderate repeatability (0.58±0.04) and significant (P &lt; 0.05) negative genetic correlations (±SE) with reproductive performance traits (from -0.41±0.16 to -0.49±0.12), PCV (-0.53±0.09), and HL (-0.45±0.16). These results indicated that the selection of mink with a lower ELISA-G score could not only decrease the anti-AMDV antibody level and the extent of anemia but also improve the female reproductive performance and the harvest length of mink without causing adverse influences on the pelt quality. Hence, ELISA-G could be applied as an indicator for genetic selection of AD-resilient mink and help mink farmers reduce the adverse effects of AD.

scholarly journals PSII-30 The genetics of functional teats in swine

2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 215-216
Author(s):  
Audrey L Earnhardt ◽  
Mark Knauer
Keyword(s):  
Fixed Effects ◽  
Genetic Correlations ◽  
Well Being ◽  
Linear Regression Models ◽  
Large White ◽  
Breeding Goal ◽  
Teat Number ◽  
Relationship Of ◽  
Piglet Survival ◽  
Negative Linear Relationship

Abstract The objective of this study was to evaluate the genetics of functional teats in swine. Piglet survival is of great importance for swine producers throughout the world due to its relationship with animal well-being and farm profitability. Availability and accessibility of functional teats on a sow during lactation is essential for enhancing piglet livability. Teat traits including total teat number (TT), functional teat number (FT), and non-functional teat number (NFT), were observed and recorded on 3,249 Landrace × Large White F1 sows. Damaged teat number (DT) and functional mammary gland number (FG) were also observed on sows prior to weaning. Variance components were estimated using AIREMLF90, with parity and farm as fixed effects. Means for TT, FT and NFT at farrowing were 14.94, 13.91 and 1.03, respectively, and 14.43, 13.02 and 1.15, respectively at weaning. Means for TT and FT were greater (P &lt; 0.01) at farrowing than at weaning. Heritability estimates for TT, FT and NFT ranged between 0.19 and 0.30, 0.17 and 0.24, and 0.12 and 0.16, respectively. Total teat number and functional teat number had positive genetic correlation estimates ranging from 0.74 to 0.77. Functional mammary glands had a negative linear relationship of -1.16 with DT, and genetic correlations of 0.87 and -0.83 with FT and NFT, respectively. Linear regression models relating TT and FT to number of piglets weaned revealed that an increase of one functional teat at farrowing increased number weaned by 0.26. Overall, there was sufficient genetic variation for total teat number and functional teat number signifying that genetic gains from selecting for these traits is possible. Results also suggest that by focusing selection on functional teat number, an increase in non-functional teat number can be avoided. Therefore, utilizing functional teat number in the breeding goal should improve the general teat quality and sow performance.

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