GENETIC PARAMETERS FOR MATERNAL TRAITS IN BEEF CATTLE

1988 ◽  
Vol 68 (1) ◽  
pp. 119-128 ◽  
Author(s):  
D. TRUS ◽  
J. W. WILTON
Keyword(s):  
Beef Cattle ◽  
Fixed Effects ◽  
Genetic Correlations ◽  
Monitoring Program ◽  
Parameter Estimates ◽  
Genetic Trend ◽  
Calving Ease ◽  
Modified Method ◽  
Maternal Heritability ◽  
Maternal Grandsire

Direct (D) and maternal (M) parameters for birth weight (BW), preweaning gain (WG) and calving ease (CE) were estimated for Angus (AN), Hereford (HE), Charolais (CH), Simmental (SM) and Shorthorn (SS). Data for the study were collected by Agriculture Canada from 1973 to 1983 for use in the National Sire Monitoring Program. Variances were estimated for each breed by a modified Method IV applied to a sire-maternal grandsire model with herd-year-seasons and age of dam × sex of calf as fixed effects. Genetic correlations (D/M) between D and M effects for WG in AN, HE, SS, CH and SM were −0.54, −0.42, −0.14, −0.26 and −0.45, respectively. Corresponding estimates of direct heritability for WG were 0.39, 0.30, 0.39, 0.27 and 0.43 and of maternal heritability 0.21, 0.27, 0.26, 0.16 and 0.20. Estimates for BW were similar to those for WG. Estimates of the D/M correlation for CE were −0.43, −0.15, −0.32, −0.74 and −0.27, of the direct heritability 0.28, 0.17, 0.19, 0.33 and 0.21, and of the maternal heritability 0.22, 0.13, 0.19, 0.23 and 0.27 for AN, HE, SS, CH and SM, respectively. Genetic trend and the introduction of new genetic lines are expected to have influenced parameter estimates. Due to negative D/M correlation estimates and moderate maternal heritabilities, selection for both the D and M components of maternal traits is advised. Key words: Variance, direct, maternal, heritability, genetic correlation, beef cattle

scholarly journals Comparison of models for estimating genetic parameters and predicting breeding values for birth weight and calving ease in Czech Charolais cattle 

2014 ◽  
Vol 59 (No. 7) ◽  
pp. 302-309 ◽  
Author(s):  
L. Vostrý ◽  
Z. Veselá ◽  
A. Svitáková ◽  
H. Vostrá Vydrová
Keyword(s):  
Animal Model ◽  
Birth Weight ◽  
Beef Cattle ◽  
Fixed Effects ◽  
Genetic Parameters ◽  
Genetic Correlations ◽  
Genetic Effects ◽  
Parameters Estimation ◽  
Calving Ease ◽  
Heritability Estimates

The most appropriate model for genetic parameters estimation for calving ease and birth weight in beef cattle was selected. A total of 27 402 field records were available from the Czech Charolais breed. For estimation of genetic parameters for calving ease and body weight, three bivariate models were tested: a linear-linear animal model (L-LM) with calving ease classified into four categories (1 – easy; 2–4 – most difficult), a linear-linear animal model (SC-LM) in which calving ease scores were transformed into Snell scores (Snell 1964) and expressed as percentage of assisted calving (ranging 0–100%), and a bivariate threshold-linear animal model (T-LM) with calving ease classified into four categories (1 – easy, 2–4 – most difficult). All tested models included fixed effects for contemporary group (herd × year × season), age of dam, sex and breed of a calf. Random effects included direct and maternal genetic effects, maternal permanent environmental effect, and residual error. Direct heritability estimates for calving ease and birth weight were, with the use of L-LM, SC-LM, and T-LM, from 0.096 ± 0.013 to 0.226 ± 0.024 and from 0.210 ± 0.024 to 0.225 ± 0.026, respectively. Maternal heritability estimates for calving ease and birth weight were, with the use of L-LM, SC-LM, and T-LM, from 0.060 ± 0.031 to 0.104 ± 0.125 and from 0.074 ± 0.041 to 0.075 ± 0.040, respectively. Genetic correlations of direct calving ease with direct birth weight ranged from 0.46 ± 0.06 to 0.50 ± 0.06 for all tested models; whereas maternal genetic correlations between these two traits ranged from 0.24 ± 0.17 to 0.25 ± 0.53. Correlations between direct and maternal genetic effects within-trait were negative and substantial for all tested models (ranging from –0.574 ± 0.125 to –0.680 ± 0.141 for calving ease and from –0.553 ± 0.122 to –0.558 ± 0.118 for birth weight, respectively), illustrating the importance of including this parameter in calving ease evaluations. Results indicate that any of the tested models could be used to reliably estimate genetic parameters for calving ease for beef cattle in the Czech Republic. However, because of advantages in computation time and practical considerations, genetic analysis using SC-LM (transformed data) is recommended.

PSIII-8 Genetic Parameter Estimates for Bull Prolificacy and Its Relationship with Scrotal Circumference in a Commercial Beef Cattle Population

2021 ◽  
Vol 99 (Supplement_1) ◽  
pp. 158-159
Author(s):  
Chad A Russell ◽  
E J Pollak ◽  
Matthew L Spangler
Keyword(s):  
Beef Cattle ◽  
Breeding Season ◽  
Random Effects ◽  
Fixed Effects ◽  
Genetic Parameter ◽  
Additive Genetic Effect ◽  
Parameter Estimates ◽  
Contemporary Group ◽  
Scrotal Circumference ◽  
Heritability Estimates

Abstract The commercial beef cattle industry relies heavily on the use of natural service sires. Either due to the size of breeding herds or to safe-guard against injury during the breeding season, multiple-sire breeding pastures are utilized. Although each bull might be given an equal opportunity to produce offspring, evidence suggest that there is substantial variation in the number of calves sired by each bull in a breeding pasture. DNA-based paternity assignment enables correct assignment of calves to their respective sires in multi-sire pastures and presents an opportunity to investigate the degree to which this trait complex is under genetic control. Field data from a large commercial ranch were used to estimate genetic parameters for calf count (CC; n=623) and yearling scrotal circumference (SC; n=1962) using univariate and bivariate animal models. Average CC and SC were 12.1±11.1 calves and 35.4±2.30 cm, respectively. Average number breeding seasons per bull and bulls per contemporary group were 1.40 and 24.9, respectively. The model for CC included fixed effects of age during the breeding season (in years) and contemporary group (concatenation of breeding pasture and year). Random effects included additive genetic and permanent environmental effects, and a residual. The model for SC included fixed effects of age (in days) and contemporary group (concatenation of month and year of measurement). Random effects included an additive genetic effect and a residual. Univariate model heritability estimates for CC and SC were 0.237±0.156 and 0.456±0.072, respectively. Similarly, the bivariate model resulted in heritability estimates for CC and SC of 0.240±0.155 and 0.461±0.072, respectively. Repeatability estimates for CC from univariate and bivariate models were 0.517±0.054 and 0.518±0.053, respectively. The estimate of genetic correlation between CC and SC was 0.270±0.220. Parameter estimates suggest that both CC and SC would respond favorably to selection and that CC is moderately repeatable.

scholarly journals Analysis of non-genetic and genetic influences underlying the growth of Kajli lambs

2020 ◽  
Vol 50 (4) ◽  
pp. 613-625
Author(s):  
A. Ali ◽  
K. Javed ◽  
I. Zahoor ◽  
K.M. Anjum
Keyword(s):  
Birth Weight ◽  
Genetic Correlation ◽  
Fixed Effects ◽  
Genetic Correlations ◽  
Breeding Value ◽  
Season Of Birth ◽  
Genetic Trend ◽  
Breeding Values ◽  
Heritability Estimates ◽  
Birth Type

Data on 2931 Kajli lambs, born from 2007 to 2018, were used to quantify environmental and genetic effects on growth performance of Kajli sheep. Traits considered for evaluation were birth weight (BWT), 120-day adjusted weight (120DWT), 180-day adjusted weight (180DWT), 270-day adjusted weight (270DWT), and 365-day adjusted weight (365DWT). Fixed effects of year of birth, season of birth, sex, birth type, and dam age on these traits were evaluated using linear procedures of SAS, 9.1. Similarly, BWT, 120DWT, 180DWT, and 270DWT were used as fixed effects mixed model analyses. Variance components, heritability and breeding values were estimated by restricted maximum likelihood. The genetic trend for each trait was obtained by regression of the estimated breeding values (EBV) on year of birth. Analyses revealed substantial influence of birth year on all traits. Sex and birth type were the significant sources of variation for BWT and 120DWT. Season of birth did not influence birth weight meaningfully, but had a significant role in the expression of 120DWT, 180DWT, and 270DWT. Heritability estimates were generally low (0.003 ± 0.018 to 0.099 ± 0.067) for all traits. With the exception of the genetic correlation of 180DWT and 365DWT, the genetic correlations between trait were strong and positive. Only 365DWT had a positive genetic trend. Although the heritability estimates for almost all weight traits were low, high and positive genetic correlations between BWT and other weight traits suggest that selection based on BWT would result in the improvement of other weight traits as a correlated response.Keywords: bodyweight, breeding value, genetic correlation, sheep

scholarly journals Selection of a suitable data set and model for the estimation of genetic parameters of the weaning weight in beef cattle

2007 ◽  
Vol 50 (6) ◽  
pp. 562-574
Author(s):  
L. Vostrý ◽  
J. Přibyl ◽  
Z. Veselá ◽  
V. Jakubec
Keyword(s):  
Beef Cattle ◽  
Fixed Effects ◽  
Genetic Parameters ◽  
Genetic Correlations ◽  
Genetic Effect ◽  
Suitable Model ◽  
Data Set ◽  
Weaning Weight ◽  
Estimation Of Genetic Parameters ◽  
Selection Of

Abstract. The objective of this paper was to select a suitable data subset and statistical model for the estimation of genetic parameters for weaning weight of beef cattle in the Czech Republic. Nine subsets were tested for the selection of a suitable subset. The subsets differed from each other in the limit of sampling criteria. The most suitable subset satisfied these conditions: at least 5 individuals per each sire, 5 individuals per HYS (herd, year, season), 2 sires per HYS, and individuals per dams that have at least one half-sister and two offspring (n = 4 806). The selection of a suitable model was carried out from 10 models. These models comprised some of the random effects: direct genetic effect, maternal genetic effect, permanent maternal environment effect, HYS, sire × herd or sire × year interaction, and some of the fixed effects: dam’s age, sex (young bull, heifer × single, twin born), HYS, year, herd. The direct heritability (h2a) ranged from 0.06 to 0.17, of maternal heritability (h2m) from 0.03 to 0.06. The genetic correlations between the direct and maternal effect (ram) were in the range of –0.15 –0.42.

REGRESSIONS OF PROGENY PROOFS FOR CALVING EASE AND GROWTH ON TEST STATION PERFORMANCE OF CHAROLAIS AND HEREFORD BEEF BULLS

1988 ◽  
Vol 68 (1) ◽  
pp. 107-117
Author(s):  
G. H. CROW ◽  
S. AMAL ◽  
M. DONETZ
Keyword(s):  
Performance Test ◽  
Genetic Correlations ◽  
Monitoring Program ◽  
Error Variance ◽  
Regression Coefficients ◽  
Performance Information ◽  
Calving Ease ◽  
Beef Bulls ◽  
Group Regression ◽  
Score Point

Performance records of 32 Charolais and 52 Hereford beef bulls tested at the Manitoba Bull Test Station for which progeny proofs were available (1984 Canadian Beef Sire Monitoring Program) were analyzed to determine if performance-tested bulls with progeny proofs were representative of the selected group of bulls which were eligible for sale (i.e, had station indexes of 95 or more) and to determine the regressions of progeny proofs on bull performance. The bull performance information included start and end of test weights, interim weights and gains, all expressed as deviations from their respective year-breed contemporary group means. This group of 84 bulls was not significantly different in test gains from the group of all bulls tested over the years 1976–1984 with station indexes of 95 or more. Regressions of progeny proofs for calving ease (CE, in score point units), preweaning gain (WG), yearling gain (YG) and postweaning growth (YG–WG) on bull weights and gains were estimated within breeds, weighting proofs by their prediction error variance. The only significant (P < 0.05) regressions of CE proof on bull performance were for bull weights in the Charolais group. Regression coefficients of WG and YG proofs on bull weights and gains were similar in magnitude with the coefficients for the Hereford breed being significantly different from zero more often than those for the Charolais breed. Effective heritabilities and genetic correlations between bull performance traits and progeny traits were estimated and, for traits defined similarly on parent and progeny, the estimates were similar to literature values. Test station procedures seemed to be effective in that bull performance was an indicator of subsequent progeny performance. Key words: Beef cattle, performance test, progeny test, heritability

scholarly journals Estimates of direct and maternal genetic parameters for weight traits and backfat thickness in a multibreed population of beef cattle

1999 ◽  
Vol 79 (4) ◽  
pp. 433-439 ◽  
Author(s):  
J. J. Tosh ◽  
R. A. Kemp ◽  
D. R. Ward
Keyword(s):  
Beef Cattle ◽  
Maternal Effects ◽  
Variance Components ◽  
Genetic Parameters ◽  
Genetic Correlations ◽  
Backfat Thickness ◽  
Residual Effects ◽  
Parameter Estimates ◽  
Ratio Test ◽  
Environmental Correlations

Variance components were estimated for weight at birth, weaning, and 365 d of age, and yearling ultrasonic backfat thickness in a multibreed population of beef cattle. Data (n = 5880) were available on F1 animals and various crosses leading up to, and including, a composite breed (7/16 British, 1/4 Charolais, 1/4 Simmental, and 1/16 Limousin). Single- and two-trait analyses were conducted using an animal model and derivative-free REML procedures. Covariates representing fractional contributions of each of the four purebred groups and average heterotic effects, both direct and maternal, accounted for breed composition. Direct and maternal genetic, maternal permanent environmental, and residual effects were the random variables. Only minor differences existed between parameter estimates obtained from the various analyses. Mean direct heritabilities were 0.51, 0.33, 0.48, and 0.37 for weight at birth, weaning, and 365-d, and backfat, respectively, which, though well within the range of published estimates, seemed higher than average, indicating diversity in the founding purebreds. Mean maternal heritabilites were 0.09, 0.13, and 0.08 for the three consecutive weights. A likelihood ratio test showed maternal heritability and(or) the direct-maternal correlation was important (P < 0.001) for 365-d weight. Averaged across weights, the direct-maternal correlation was 0.07, lacking evidence of genetic antagonism. No age of dam or random maternal effects on backfat were apparent. Phenotypic correlations between weight at birth and weaning and weight at weaning and 365-d were 0.46 and 0.76, respectively. Though moderate between birth and weaning weight, maternal genetic and permanent environmental correlations between weaning and 365-d weight approached unity, demonstrating maternal carryover effects. Phenotypic and genetic correlations of 0.19 and –0.13, respectively, implied a limited association between 365-d weight and backfat, which possibly would have been stronger had fat been measured later in life. Estimates of variance components suitable for general use can be obtained from data from multibreed animals by considering breed and heterotic effects. Key words: Beef cattle, crossbreds, genetic parameters, heritability, maternal effects

Genetic association between cows’ stayability to three years of age and juvenile growth traits in Canadian Angus herds

2005 ◽  
Vol 85 (2) ◽  
pp. 139-143 ◽  
Author(s):  
D. P. Rasali ◽  
G. H. Crow ◽  
J. N. B. Shrestha ◽  
A. D. Kennedy ◽  
A. Brûlé-Babel
Keyword(s):  
Fixed Effects ◽  
Growth Traits ◽  
Genetic Correlations ◽  
Genetic Effect ◽  
Genetic Effects ◽  
Birth Season ◽  
Angus Cattle ◽  
Body Weights ◽  
Direct Genetic Effect ◽  
Maternal Heritability

Bivariate linear animal models were fit using MTDFREML programs for the analysis of cows’ stayability to 3 yr (STAY3, n = 1, 703) as a binary scored trait paired with body weights at birth (BW, n = 6,116), 205-d weaning (WW, n = 5,360,) and 1 yr of age (YW, n = 5250) in Angus cattle. For STAY3, the model included a fixed effect due to herd ×year of cow’s birth along with a random direct genetic effect. For each of BW, WW and YW, the model included fixed effects due to herd ×birth year, birth season, birth type, calf’s sex and the age of dam (as linear and quadratic covariates), while the random effects were direct and maternal genetic effects and permanent maternal environmental effects. Survival analysis revealed that the risk of cows, 10 yr or less in age, being culled from five Canadian Angus herds was highest between 2 and 3 yr of age. The direct heritability (h2) estimates for BW, WW and YW were 0.54, 0.73 and 0.47, respectively, and corresponding maternal heritability estimates were 0.14, 0.33 and 0.13, respectively. Furthermore, the direct h2 estimate for STAY3 from three bivariate analyses was 0.23–0.24. Estimates of direct-maternal genetic correlations of BW, WW and YW were -0.18, -0.70 and -0.39, respectively. The direct genetic correlations of STAY3 with BW, WW and YW were -0.15 to -0.09 indicating that selection for growth would have less detrimental influence on the stayability trait of cows. The correlations of direct genetic effects of STAY3 with maternal genetic effects of BW, WW and YW were between 0.20 and 0.25, indicating their favorable relationships as correlated traits. Key words: Stayability, growth traits, heritability, genetic correlations, beef cattle

scholarly journals 37 Genetic parameter estimates for days on feed, age at slaughter, and carcass traits in a multi-breed beef cattle population

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 21-22
Author(s):  
Lindsay R Upperman ◽  
Larry A Kuehn ◽  
Matthew L Spangler
Keyword(s):  
Fixed Effects ◽  
Phenotypic Variability ◽  
Genetic Parameter ◽  
Carcass Traits ◽  
Genetic Correlations ◽  
Live Weight ◽  
Experimental Treatment ◽  
Parameter Estimates ◽  
Marbling Score ◽  
Heritability Estimates

Abstract The objective of this study was to estimate genetic parameters for days on feed (DOF), age at slaughter (AAS), and their relationships with carcass traits, including: marbling score (MARB), adjusted fat thickness (AFT), hot carcass weight (HCW), ribeye area (REA), and final live weight (FW). Data were from steers and heifers (n = 7,747) from the Germplasm Evaluation Program at the U.S. Meat Animal Research Center. All traits were analyzed with univariate and bivariate animal models using ASReml. Fixed effects fitted for all models included contemporary group (concatenation of birth year and season, sex, and experimental treatment group), breed fractions, and direct heterosis. Different endpoints were also investigated by fitting fixed linear covariates of AFT, HCW, REA, MARB, FW, and age (except AAS and DOF). For a given bivariate analyses, both traits were adjusted to the same endpoint. Univariate heritability estimates for AFT, AAS, DOF, FW, HCW, MARB, and REA ranged from 0.45–0.52, 0.52–0.59, 0.33–0.39, 0.34–0.55, 0.34–0.55, 0.54–0.55, and 0.50–0.56, respectively. Covariates of MARB and AFT led to the highest and lowest, respectively, heritability estimates for AAS and DOF. Depending on the endpoint, genetic correlations between AAS and AFT, FW, HCW, MARB, and REA ranged from 0.16 to 0.32, -0.08 to 0.33, 0.19 to 0.36, 0.14 to 0.20, and -0.06 to 0.13 (Table 1). Genetic correlations between DOF and AFT, MARB, and REA were negligible. Genetic correlations between DOF, FW, and HCW ranged from -0.10 to 0.29 and -0.37 to -0.17. Standard errors were less than 0.07 for all estimates. Phenotypic variability in DOF was low, and increased variability in AAS was due to differences in date of birth and thus weaning age. Results indicate DOF and AAS are moderately to highly heritable and generally lowly correlated with routine carcass traits. The USDA is an equal opportunity employer.

scholarly journals Estimation of animal × environment interaction in Czech beef cattle

2009 ◽  
Vol 52 (1) ◽  
pp. 15-22
Author(s):  
L. Vostrý ◽  
J. Přibyl ◽  
W. Schlote ◽  
Z. Veselá ◽  
V. Jakubec ◽  
...  
Keyword(s):  
Animal Model ◽  
Czech Republic ◽  
Beef Cattle ◽  
Variance Components ◽  
Genetic Correlations ◽  
Environment Interaction ◽  
Multiple Trait ◽  
The Czech Republic ◽  
Standard Deviations ◽  
Maternal Heritability

Abstract. The objective was the estimation of animal × environment interaction for weaning weight (WWT) of the most frequent breeds of beef cattle in the Czech Republic. The environment was represented by 3 areas: Mountain (1), Foothills (2) and Lowland (3). A pairwise analysis was carried out between the areas: 1 vs 2 (n=5 149) and 2 vs 3 (n=4 971) for the estimation of (co)variance components and genetic correlations between the environments. A multiple-trait animal model was used where weaning weights in different areas were considered as different traits. The direct and maternal heritability estimates of WWT were for area (1): 0.12 (direct) and 0.05 (maternal); for (2): 0.26 and 0.11 (direct), 0.10 and 0.11 (maternal) and for (3): 0.26 (direct) 0.03 (maternal). Direct and maternal genetic correlations were between: 1 and 2 0.98 and 0.65 respectively, with standard deviations 0.03 and 0.37 respectively, and between 2 and 3: 0.82 and 0.50 respectively, with standard deviations 0.12 and 0.31 respectivly. The magnitude of the across-areas genetic correlation indicates that the animal by environment interaction was not biologically important and can be ignored in the evaluation of beef cattle in the Czech Republic.

9 EVALUATION OF FERTILITY TRAITS OF HOLSTEIN CATTLE IN ARGENTINA

2011 ◽  
Vol 23 (1) ◽  
pp. 111 ◽  
Author(s):  
F. A. Di Croce ◽  
A. M. Saxton ◽  
D. Casanova ◽  
F. N. Schrick
Keyword(s):  
Pregnancy Rate ◽  
Fixed Effects ◽  
Genetic Parameter ◽  
Genetic Correlations ◽  
The United States ◽  
Holstein Cattle ◽  
Calving Interval ◽  
Genetic Trend ◽  
Days Open ◽  
Fertility Traits

Impaired fertility is the primary reason for culling in the United States (26.5% of all disposals) and fertility rates have steadily declined during the past 30 years. The objectives of this study were 1) estimate genetic parameters and evaluate genetic correlations for fertility traits based on data from milk recording programs, and 2) evaluate genetic fertility trends in Holstein cattle in Argentina. Data representing 3 282 843 lactations and 1 622 088 animals (cows and bulls from 1936 to 2007) were used for the analysis and obtained from official records maintained by the Argentinean Holstein Association (ACHA). Lactations were standardized to 305 DIM for milk, protein, and fat. Days open (DO), calving interval (CI), age to first calving (AFC), and daughter pregnancy rate (DPR) were selected for genetic parameter estimation. Daughter pregnancy rate was calculated as described by (Kuhn et al. 2004 J. Dairy Sci. 87, 2277–2284). Animal models by lactation for each fertility trait included contemporary group (dairy herd and calving year), calving month, animal effect, milk production as a covariate, and error term. Multiple-trait derivative-free restricted maximum likelihood (MTDFREML) was used to estimate covariance components. Solutions for fixed effects, breeding values, and sampling variances (accuracies) were obtained for each trait. The fertility index ($F = –0.28 × AFC ± 4.9 × CI) was calculated using the economic rates as reported by (Gonzalez-Recio et al. 2004 J. Dairy Sci. 87, 3053–3061). First lactation/parities were utilised for estimating correlations among BLUPs for DO, CI, DPR, AFC, and $F. In general, moderate and high genetic correlations were observed (from 0.238 to 0.999; P < 0.001). Days open and calving interval showed high negative associations with DPR (–0.999, –0.648) and $F (–0.612, Q0.981). Results from the correlation analysis suggest that CI and $F are qualified indicators of fertility in lactating dairy Holstein and relate well with all the other traits. The index, $F, benefits by including AFC as a measure of initial reproductive efficiency followed by the inclusion of CI which measures success of inseminations. Genetic trend for AFC showed a decrease of 2.76 days per year between 1970 and 2000 for sires. Similarly, trends for CI resulted in decreases of 0.45 days per year between 1970 and 2000 for sires. During the same period, DPR increased by 0.02 percent per year in sires. Using current dollars values, $F increased 2.99 dollars per year for sires. Results indicate progress in the genetic trend for fertility traits in the Holstein population of Argentina, with higher improvement in sires compared with dams. Trends visually showed faster improvement after 1980, possibly due to extensive importation of US and Canadian bulls and semen (72% of bulls born after 1986) and selection for productive life introduced in 1993. Supported by Asociacion Criadores de Holando Argentino (ACHA).

Sign in / Sign up

Export Citation Format

Share Document