Estimates of heritabilities of Canadian Holstein conformation traits by threshold model

1991 ◽  
Vol 71 (3) ◽  
pp. 629-632 ◽  
Author(s):  
J. Jamrozik ◽  
L. R. Schaeffer ◽  
E. B. Burnside ◽  
B. P. Sullivan
Keyword(s):  
Animal Model ◽  
Em Algorithm ◽  
Variance Components ◽  
Fixed Effects ◽  
Threshold Model ◽  
Model Data ◽  
Stage Of Lactation ◽  
Continuous Scale ◽  
Type Traits ◽  
Holstein Population

Sire variances for 30 conformation traits on Canadian Holsteins were estimated on the underlying continuous scale using a single trait threshold linear model. Data were linearized first classifications on 66 617 cows by 3305 sires, classified since February 1988. The model included a random sire effect and fixed effects of herd-round of classification-classifier, age at classification and stage of lactation at classification. Sires were assumed unrelated in this study. Variance components for sires were estimated by REML EM algorithm. Estimates of heritabilities were generally larger than those currently used in genetic evaluation for type traits in Canadian Holstein population. The new heritabilities are recommended for use in a traditional linear animal model procedure. Key words: Variance components, threshold model, type traits

scholarly journals Use of individual race results in the estimation of genetic parameters of trotting performance for Finnhorse and Standardbred trotters

1999 ◽  
Vol 8 (4-5) ◽  
pp. 353-363 ◽  
Author(s):  
T. THUNEBERG-SELONEN ◽  
J. PÖSÖ ◽  
E. MÄNTYSAARI
Keyword(s):  
Animal Model ◽  
Maximum Likelihood ◽  
Variance Components ◽  
Fixed Effects ◽  
Environmental Effect ◽  
Genetic Parameters ◽  
Genetic Effect ◽  
Additive Genetic Effect ◽  
Performance Traits ◽  
Estimation Of Genetic Parameters

The heritability and repeatability for trotting performance traits were estimated from individual race results. Data comprised of records from 1991 to 1995 for 4808 Finnhorses and from 1993 to 1995 for 5869 Standardbred trotters. The statistical model included the additive genetic effect of an animal and two permanent environmental effects, and the fixed effects of sex, age, starting method*starting lane combination, driver and race. The first permanent environmental effect described repeatability over a horse’s career while the second one characterized repeatability within a racing year. Variance components for three trotting performance traits were estimated by the animal model and the method of restricted maximum likelihood (REML). Heritability and repeatability estimates were moderately high for time at finish (h 2 =0.23–0.28 and r=0.50–0.57), moderate for ranking within a race (h 2 =0.12 and r=0.25) and low for earnings (h 2 =0.05–0.09 and r=0.15–0.18). Time at finish seemed to be the most usable measure of trotting performance because of its wide information substance. However, time at finish does not take into account records of disqualified horses or of those which did not finish, but use of earnings, either from individual race results or preferably from annual records, is one possible way to consider records of such horses.;

ESTIMATES OF VARIANCE COMPONENTS FOR HOLSTEIN-TYPE TRAITS

1983 ◽  
Vol 63 (4) ◽  
pp. 763-771 ◽  
Author(s):  
L. R. SCHAEFFER
Keyword(s):  
Key Words ◽  
Variance Components ◽  
Genetic Parameters ◽  
New Method ◽  
Multiple Trait ◽  
Stage Of Lactation ◽  
Holstein Friesian ◽  
Type Traits ◽  
Highly Correlated ◽  
Friesian Cows

Sire and error variances and covariances for 27 conformation traits were estimated from 424 875 Holstein-Friesian cows classified since June 1976. Estimates were obtained by Henderson's new method (Diagonal-MIVQUE) with a model that included 46 age by parity groups, 10 stage of lactation groups, herd-round-classifier effects, and nine covariates of dam's type and sire effects. Heritabilities were generally low from 0.10 for feet and legs to 0.29 for capacity, and from 0.05 for rear heel to 0.42 stature. Final class had a heritability of 0.17 and was highly correlated with traits related to mammary system (0.62–0.94). A multiple trait analysis of type could utilize the estimates from this study. Key words: Genetic parameters, type traits, Henderson's new method

Genetic and phenotypic associations of type traits and body condition score with dry matter intake, milk yield, and number of breedings in first lactation Canadian Holstein cows

2016 ◽  
Vol 96 (3) ◽  
pp. 434-447 ◽  
Author(s):  
G. Bilal ◽  
R.I. Cue ◽  
J.F. Hayes
Keyword(s):  
Milk Yield ◽  
Body Condition ◽  
Feed Intake ◽  
Fixed Effects ◽  
Dry Matter ◽  
Body Condition Score ◽  
Dry Matter Intake ◽  
Stage Of Lactation ◽  
Condition Score ◽  
Type Traits

The objective of the present study was to estimate genetic parameters of milk yield (MY), intake traits, type traits, body condition score (BCS), and number of breedings (NOB) in first lactation Canadian Holsteins with a focus on the possibility of using type traits as an indicator of feed intake. Data were obtained from the Canadian Dairy Network and Valacta. A mixed linear model was fitted under REML for the statistical analysis. The multivariate (five traits) model included the fixed effects of age at calving, stage of lactation, and herd-round-classifier for type traits; age at calving, stage of lactation, and herd–year–season of calving (HYS) for BCS; age at calving and HYS for MY, feed intake, and NOB. Animal and residual effects were fitted as random effects for all traits. Estimates of heritabilities for MY, dry matter intake (DMI), angularity, body depth, stature, dairy strength, final score, BCS, and NOB were 0.41, 0.13, 0.24, 0.30, 0.50, 0.30, 0.22, 0.20, and 0.02, respectively. Genetic correlations between type traits and DMI ranged from 0.16 to 0.60. Results indicate that type traits appear to have the potential to predict DMI as a combination/index of two or more traits.

scholarly journals Analysis of longevity in the Slovak Pinzgau population – extension to the animal model

2013 ◽  
Vol 58 (No. 7) ◽  
pp. 289-295 ◽  
Author(s):  
G. Mészáros ◽  
O. Kadlečík ◽  
R. Kasarda ◽  
J. Sölkner
Keyword(s):  
Animal Model ◽  
Milk Production ◽  
Fixed Effects ◽  
Herd Size ◽  
Size Change ◽  
Breeding Values ◽  
The Third ◽  
Stage Of Lactation ◽  
Increased Risk ◽  
High Age

Breeding values for length of productive life in Slovak Pinzgau cattle were estimated using survival analysis. As the results were corrected for milk production, the final breeding values represented the ability of cows to avoid culling from reasons other than milk production. In addition to the relative milk yield, the risk of culling was also studied in connection with the herd and year of calving, parity and stage of lactation, herd size change and age at the first calving. Among the fixed effects, the low milk production, high age at the first calving, and decreasing herd size were associated with increased risk of culling. The risk was non-linear for parity &times; stage of lactation classes, decreasing within the first parity and increasing during later parities. Two genetic random effects were considered in separate models: the sire of the cow and the animal itself, both with the corresponding pedigree records up to the third generation. The genetic effects were estimated in separate runs, but the rest of the model remained unchanged. Heritability was h<sup>2 </sup>= 0.08 for sire model, confirming the results of an earlier study in the Slovak Pinzgau population. The computational feasibility of the animal model for estimation of breeding values for cows was confirmed in this study. The new breeding values could be computed for each cow, accounting for all relationships within the population. The estimated heritability for the animal model was h<sup>2 </sup>= 0.11, which should be used later on for animal breeding purposes. &nbsp;

130 Utilization of Nutrack to Assess Variance Components and Heritability of Activity Traits

2021 ◽  
Vol 99 (Supplement_1) ◽  
pp. 17-17
Author(s):  
Lexi M Ostrand ◽  
Melanie D Trenhaile-Grannemann ◽  
Garrett See ◽  
Ty B Schmidt ◽  
Eric Psota ◽  
...  
Keyword(s):  
Animal Model ◽  
Mixed Models ◽  
Variance Components ◽  
Average Speed ◽  
Genetic Variances ◽  
Sow Longevity ◽  
Selection Decisions ◽  
Recorded Data ◽  
Residual Variances ◽  
And Behavior

Abstract Overall activity and behavior are integral components of sows remaining productive in the herd. This investigation studied overall activity of group housed replacement gilts and the heritability of various activity traits. Beginning around 20 wk of age, video recorded data of approximately 75 gilts/group for a total of 2,378 gilts over 32 groups was collected for 7 consecutive d using the NUtrack System, which tracks distance travelled (m), avg speed (m/s), angle rotated (degrees), and time standing (s), sitting (s), eating (s), and laying (s). The recorded phenotypes were standardized to the distribution observed within a pen for each group. The final values used for analysis were the average daily standardized values. Data were analyzed using mixed models (RStudio V 1.2.5033) including effects of sire, dam, dam’s sire and dam, dam’s grandsire and granddam, farrowing group, barn, pen, and on-test date. Sire had an effect on every activity trait P &lt; 0.001), and dam had an effect on average speed (P &lt; 0.001). The dam’s sire had an effect on all activity traits (P &lt; 0.001) and the dam’s grandsire had an effect on average speed (P &lt; 0.001). Heritabilities and variance components of activity traits were estimated in ASReml 4 using an animal model with a two-generation pedigree. Genetic variances are 0.17 +/- 0.029, 0.19 +/- 0.034, and 0.11 +/- 0.024, residual variances are 0.37 +/- 0.023, 0.41 +/- 0.027, and 0.41 +/- 0.022, phenotypic variances are 0.54 +/- 0.018, 0.60 +/- 0.020, and 0.52 +/- 0.016, and heritabilities are 0.32 +/- 0.048, 0.32 +/- 0.049, and 0.21 +/- 0.044 for average speed, distance, and lie respectively. NUtrack offers potential to aid in selection decisions. Given the results presented herein, continued investigation into these activity traits and their association with sow longevity is warranted.

scholarly journals Nicotine Pharmacokinetics in Rats Is Altered as a Function of Age, Impacting the Interpretation of Animal Model Data

2014 ◽  
Vol 42 (9) ◽  
pp. 1447-1455 ◽  
Author(s):  
Evelyn L. Craig ◽  
Bin Zhao ◽  
Jason Z. Cui ◽  
Maria Novalen ◽  
Sharon Miksys ◽  
...  
Keyword(s):  
Animal Model ◽  
Model Data ◽  
Nicotine Pharmacokinetics ◽  
Pharmacokinetics In Rats

PSVIII-5 Genetic parameters of thrombin as a proxy for horn fly abundance in beef cattle

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 239-239
Author(s):  
Ashley S Ling ◽  
Taylor Krause ◽  
Amanda Warner ◽  
Jason Duggin ◽  
Bradley Heins ◽  
...  
Keyword(s):  
Beef Cattle ◽  
Fixed Effects ◽  
Large Scale ◽  
Genetic Basis ◽  
Threshold Model ◽  
Economic Losses ◽  
Small Data ◽  
Horn Fly ◽  
Improvement Programs ◽  
Highest Posterior Density

Abstract Horn flies (Haematobia irritans) are a major nuisance to cattle, especially in warm, humid regions, and are estimated to cause economic losses in excess of $1 billion annually to the U.S. beef cattle industry. Variation in horn fly tolerance has been reported within and across breeds, and heritability estimates ranging between 10 and 80% show a clear genetic basis. However, collecting fly abundance phenotypes is costly and logistically demanding, which precludes large-scale implementation. Consequently, finding correlated phenotypes and endo-phenotypes that are heritable and relatively easy to measure would facilitate implementation of horn fly tolerance genetic improvement programs. Thrombin (TH), a blood coagulation precursor, has a reported association with horn fly count variation within and across cattle breeds. In this study, the genetic basis of thrombin in beef cattle was investigated. Blood samples and horn fly count were collected on 360 cows and heifers twice during the summer of 2019 (June and August). Due to uncertainty associated with assessment of horn fly abundance and thrombin and the fact that economic losses occur only when fly abundance exceeds a certain threshold, thrombin was categorized into 4 classes (1=TH &gt; 500 ng/ml; 2=250&lt; TH&lt; 500 ng/ml; 3=100&lt; TH&lt; 250 ng/ml; and 4=TH&lt; 100 ng/ml). The trait was analyzed using linear (continuous) and threshold (discrete) mixed models. Both models included farm, pregnancy status, and cow age as fixed effects and additive and permanent environment random effects. The pedigree included 642 animals. Estimates of heritability were 0.24 and 0.29 using linear and threshold models, respectively. Estimates of repeatability were slightly higher using the threshold model (0.21 vs 0.19). Despite the small data size, all estimates were non-zero based on their respective highest posterior density intervals. These results indicate reasonable genetic variation for thrombin that could be harnessed for improvement of horn fly tolerance in cattle.

scholarly journals Evaluación fenotípica y genética para características de crecimiento en la raza criolla colombiana Costeño con Cuernos

2007 ◽  
Vol 7 (2) ◽  
pp. 12 ◽  
Author(s):  
Rodrigo Alfredo Martínez ◽  
Juan Esteban Pérez ◽  
Teófilo Herazo
Keyword(s):  
Birth Weight ◽  
Variance Components ◽  
Fixed Effects ◽  
Genetic Parameters ◽  
Growth Traits ◽  
Phenotypic Correlation ◽  
Phenotypic Variance ◽  
Direct Effects ◽  
Weaning Weight ◽  
Number Of Births

<p>Se establecieron componentes de varianza, así como parámetros fenotípicos y genéticos, respecto de las variables ‘peso al nacimiento’, ‘peso al destete’ (ajustado a los 270 días) y ‘peso a los 480 días’ en un hato del ganado criollo colombiano Costeño con Cuernos. Se analizaron 2.281 registros de pesos al nacer, 1.722 de pesos al destete  y 1.086 de pesos ajustados a los 480 días utilizando la metodología de máxima verosimilitud restringida (DFREML). También se ajustó un modelo animal que incluyó efectos genéticos directos, maternos y de ambiente permanente, asumiendo como efectos fijos el año de nacimiento, el sexo del ternero y el número de partos de la madre; finalmente, se estimaron los parámetros genéticos ‘heredabilidad’, ‘repetibilildad’ y se establecieron correlaciones genéticas y fenotípicas. Se reportan bajas estimaciones de heredabilidad de los efectos directos, que varían entre 0,17 ± 0,001 y 0,21 ± 0,074 para los pesos al nacer y al destete, respectivamente; así mismo, fue baja la heredabilidad de los efectos genéticos maternos con relación al peso al nacimiento, aunque estos estimados aumentaron respecto de los pesos al nacer y al destete. Las correlaciones entre efectos directos y maternos fueron negativas, pero el mayor valor se encontró para el peso al nacimiento (-0,89). La contribución del ambiente permanente como proporción de la varianza fenotípica total fue baja y disminuyó a medida que aumentó la edad del animal.</p><p> </p><p><strong>Genetic and phenotypic evaluation to characterize growth traits of the native Colombian breed Costeño con Cuernos</strong></p><p>For a herd of native Colombian breed of cattle -Costeño con Cuernos (CCC)- estimates of variance components for phenotypic and genetic parameters were obtained for birth weight, weight at weaning (adjusted to 270 days) and weight at 480 days. Using the restricted maximum likelihood (REMI) methodology, 2281 birth weight records (PN), 1722 weaning weight records and 1086 weight records adjusted to 480 days were analyze by fitting a model which included direct and maternal genetics effects as well as permanent environmental effects, assuming that fixed effects were year of birth weight, calf gender and the mother number of births. The genetic parameters for heritability, repeatability, genetic and phenotypic correlation were estimated and genotypic and phenotypic correlation was established. Heritability estimates for direct effects are low and range from 0.17 ± 0.001 and 0.21 ± 0.074 for birth and weaning weight respectively; while estimates for maternal genetics effects were also low for PN, they were higher for weaning weight and weight at 480 days. There was a negative correlation between direct and maternal effects, and the higher value was for PN (-0.89). The contribution of the variable permanent environment measured as the contribution of the phenotypic variance was low and diminished as animal age increased.</p>

scholarly journals Animal Model Versus Polynomial Legendre Test-Day In Dairy Cattle

2020 ◽  
Vol 23 (1) ◽  
pp. 5-12
Author(s):  
Mircea Cătălin Rotar ◽  
Horia Grosu ◽  
Mihail Alexandru Gras ◽  
Rodica Ştefania Pelmuş ◽  
Cristina Lazăr ◽  
...  
Keyword(s):  
Animal Model ◽  
Dairy Cattle ◽  
Fixed Effects ◽  
Rank Correlation ◽  
Pedigree Information ◽  
Lactation Period ◽  
Data Set ◽  
Breeding Values ◽  
Normal Limits ◽  
Model Versus

AbstractThe aim of the study was to compare the classical animal model (based on total milk for 305 days) with the Test-Day model (using monthly records of milk yield from Official Records of Performances). The data set derived from a total 175 animals (cows with records, parents of these animals and the descendants) from two Romanian breeds (Romanian Black Spotted and Montbeliarde), the phenotypic and the pedigree information arisen from National Research Development Institute for Animal Biology and Nutrition (IBNA-Balotesti). The selection criteria to be included in the analysis for each cow was to have at least 3 test-days and the days in milk between 200 and 330 for the Test-Day model and the total amount of the 305- day lactation yield for classical Animal Model respectively. Both models use B.L.U.P methodology and for that reason all the estimates were adjusted for fixed effects and all the breeding values and the solution for fixed effects were estimated simultaneous. For the animal model the fixed effects used was the breed and the year of performing and for the Test-Day model was an extra one, the test day effect. The correlation calculated between test days was very high (over 90%) for consecutive tests, and was getting lower when the days between tests was higher (under 40%). Also, in terms of heritability the values were in normal limits throughout lactation, except at the beginning and end of lactation period where these values were a little bit higher. The comparison of the ranking of breeding values with Spearman rank correlation shows that in 80% of the cases the ranking was similar for both models. As the ranking correlations shows, it is certain that the two models are very similar when they are used for genetic evaluation. But, in conclusion, we can say that for a better lactation curve estimation it is recommending to use test-day model for dairy cattle.

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