Evaluating animal models comprising direct and maternal effects associated with growth rates and the Kleiber ratio in Harnali sheep

Summary The present work evaluated animal models comprising direct and maternal effects to estimate (co)variance components and genetic parameters of growth rates and Kleiber ratio in Harnali sheep. The information on pedigree and targeted traits of 1862 lambs born to 144 sires and 591 dams was collected for the period from 1998 to 2018. The traits studied were average daily gain from birth to 3 months of age (ADG1), 3 months to 6 months of age (ADG2), and 6 months to 12 months of age (ADG3) and their corresponding Kleiber ratios as KR1, KR2 and KR3, respectively. The statistical methods included the general linear model for analyzing the effects of fixed factors and animal models for deriving variance components for targeted traits. According to best model evaluated on the basis of likelihood ratio test, the estimated direct heritability was low in magnitude and ranged from 0.04 to 0.14. Direct heritability estimates for ADG1, ADG2, ADG3, KR1, KR2 and KR3 were 0.06, 0.14, 0.05, 0.04, 0.11 and 0.05, respectively. The maternal genetic effects contributed (4–7%) significantly for ADG1, KR1 and KR2 traits. The genetic correlations ranged from −0.35 ± 0.11 (ADG1-KR2) to 0.98 ± 0.01 (ADG2-KR2 and ADG3-KR3) and phenotypic correlations ranged from −0.36 ± 0.02 to 0.98 ± 0.01 for ADG1-KR2 and ADG2-KR2, respectively. The significant maternal effects along with low levels of direct effects for average daily gain and Kleiber ratio at different age group should be considered while setting selection and managerial strategies to achieve anticipated growth rates in Harnali sheep.

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(Co)variance components and genetic parameters for growth rate and Kleiber ratio in fat-tailed Mehraban sheep

Archives Animal Breeding ◽

10.7482/0003-9438-56-055 ◽

2013 ◽

Vol 56 (1) ◽

pp. 564-572 ◽

Cited By ~ 1

Author(s):

F. Ghafouri-Kesbi

Keyword(s):

Growth Rate ◽

Variance Components ◽

Genetic Parameters ◽

Average Daily Gain ◽

Genetic Correlations ◽

Phenotypic Variance ◽

Genetic Progress ◽

Kleiber Ratio ◽

Derivative Free ◽

Maternal Heritability

Abstract. The aim of the present study was to estimate (co)variance components and genetic parameters for average daily gain from birth to weaning (ADGa), weaning to 6 months (ADGb), weaning to 9 months (ADGc), 6 months to 9 months (ADGd) and corresponding Kleiber ratios (KRa, KRb, KRc and KRd) in Mehraban sheep. A derivative-free algorithm combined with a series of six univariate linear animal models was used to estimate phenotypic variance and its direct, maternal and residual components. In addition, bivariate analyses were done to estimate (co)variance components between traits. Estimates of direct heritability (h2) were 0.10, 0.11, 0.16, 0.09, 0.13, 0.13, 0.15 and 0.08 for ADGa, ADGb, ADGc, ADGd, KRa, KRb, KRc and KRd, respectively and indicate that in Mehraban sheep genes contribute very little to the variance of the growth rate and Kleiber ratio. Estimates of maternal heritability (m2) were 0.10, 0.08 and 0.05 for ADGa, KRa and KRb, respectively. Direct additive genetic correlations ranged from −0.32 (KRa-KRd) to 0.99 (ADGb-KRb) and phenotypic correlations ranged from −0.53 (ADGa- ADGd) to 0.99 (ADGa-KRa). Estimates of direct heritability and genetic correlations show that genetic improvement in efficiency of feed utilization through selection programmes is possible, though it would generate a relatively slow genetic progress.

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Genetic parameters for growth rate and Kleiber ratios of Nellore sheep

Indian Journal of Animal Research ◽

10.18805/ijar.b-3380 ◽

2018 ◽

Author(s):

I. Satish Kumar ◽

G. Gangaraju ◽

C. Vijaya Kumar ◽

Sapna Nath

Keyword(s):

Andhra Pradesh ◽

Growth Traits ◽

Average Daily Gain ◽

Genetic Correlations ◽

Research Station ◽

Genetic Progress ◽

Stages Of Growth ◽

Kleiber Ratio ◽

Nellore Sheep ◽

Daily Gain

Data on growth traits of Nellore sheep were extracted from the records maintained at Livestock Research Station, Palamaner, Andhra Pradesh, India for a period of five years. The genetic and phenotypic parameters were estimated for growth traits i.e., average daily gain (ADG) from birth to 3 months (ADGa), 3 months to 6 months (ADGb), 6 to 12 months (ADGc) and the corresponding Kleiber ratio (KR) at respective stages of growth. The non genetic factors included in the model were having significance on most of the traits studied. The heritability estimates for ADG and corresponding KR ranged from 0.17 to 0.25. The estimates of genetic correlations among the traits ranged between -0.28 (Ka-Kb) and 0.99 (ADGb-Kb). The moderate estimates of heritability, high and positive genetic correlations among the traits in the study were suggestive of moderate genetic progress in the Nellore breed of sheep through selection.

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Genetic parameters for direct and maternal effects on growth traits of sheep

Archives Animal Breeding ◽

10.5194/aab-55-603-2012 ◽

2012 ◽

Vol 55 (6) ◽

pp. 603-611 ◽

Cited By ~ 1

Author(s):

F. Ghafouri-Kesbi ◽

H. Baneh

Keyword(s):

Maternal Effects ◽

Genetic Parameters ◽

Growth Traits ◽

Average Daily Gain ◽

Genetic Correlations ◽

Selection Criterion ◽

Information Criterion ◽

Phenotypic Variance ◽

Environmental Variance ◽

Daily Gain

Abstract. The aim of the present study was to estimate (co)variance components and corresponding genetic parameters for birth weight (BW), weaning weight (WW), 6-month weight (W6), 9-month weight (W9), average daily gain from birth to weaning (WWDG), average daily gain from weaning to 6 months (W6DG) and average daily gain from 6 months to 9 months (W9DG) for a nucleus flock of Iranian Makooei sheep. Genetic parameters were estimated by REML procedure fitting six animal models including various combinations of maternal effects. The Akaike information criterion (AIC) was used to determine the most appropriate model. Estimates of direct heritability (h2) ranged from 0.13 (W6DG) to 0.32 (BW). Maternal effects were found to be important in the growth performance of the Makooei sheep, indicating the necessity of including maternal effects in the model to obtain accurate estimates of direct heritability. Estimates of maternal heritability (m2) ranged from 0.05 (W6) to 0.16 (WWDG) and the estimates of proportion of maternal permanent environmental variance to phenotypic variance (c2) were in the range between 0.05 (BW) and 0.10 (W6). Direct additive genetic correlations were positive in all cases and ranged from 0.00 (BW/W9DG) to 0.99 (WW/WWDG). Phenotypic correlations showed a broad range from −0.27 (WW/W9DG) to 0.99 (WW/WWDG). Estimates of genetic parameters showed that genetic improvement through selection programs is possible. WW would be a suitable selection criterion since it has acceptable direct heritability and relatively high genetic correlation with other traits.

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

Canadian Journal of Animal Science ◽

10.4141/a99-014 ◽

1999 ◽

Vol 79 (4) ◽

pp. 433-439 ◽

Cited By ~ 11

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

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211 Changes in genetic parameters of fitness and growth traits under genomic selection in pigs

Journal of Animal Science ◽

10.1093/jas/skz258.081 ◽

2019 ◽

Vol 97 (Supplement_3) ◽

pp. 41-41

Author(s):

Jorge Hidalgo ◽

Shogo Tsuruta ◽

Daniela Lourenco ◽

Yijian Huang ◽

Kent Gray ◽

...

Keyword(s):

Genetic Variation ◽

Genomic Selection ◽

Variance Components ◽

Genetic Parameters ◽

Growth Traits ◽

Average Daily Gain ◽

Genetic Correlations ◽

Data Set ◽

Daily Gain ◽

Over Time

Abstract Genomic selection increases intensity of selection and decreases generation interval. However, intensive selection reduces genetic variation and can strengthen undesirable genetic correlations. The purpose of this study was to investigate changes in genetic parameters of litter size (LS), number born alive (NBA), number born dead (NBD) and average daily gain (ADG) and weight at off-test (WT) in pigs over time. The data set contained 20,086 (LS), 21,230 (NBA), 21,230 (NBD), 144,717 (ADG) and 144,718 (WT) phenotypic records. Pedigree file included 369,776 animals born between 2001 and 2018, of which 39,038 were genotyped. Two trait models were evaluated (LS-ADG, LS-WT, NBA-ADG, NBA-WT, NBD-ADG and NBD-WT) using 3-year sliding subsets starting from 2010. Variance components and genetic parameters were estimated using GIBBS2F90 program. Computations were performed with (BLUP) or without (ssGBLUP) genotypes. For BLUP (ssGBLUP), the changes in heritability from 2010–2012 to 2015–2018 were 0.08 to 0.09 (0.08 to 0.06) for LS, 0.33 to 0.24 (0.37 to 0.16) for ADG, 0.11 to 0.07 (0.10 to 0.07) for NBD, and 0.32 to 0.24 (0.38 to 0.17) for WT. Differences were also observed for genetic correlations as they were -0.23 to -0.73 (-0.31 to -0.58) for LS-ADG, -0.24 to -0.74 (-0.31 to -0.50) for LS-WT, -0.33 to -0.65 (-0.41 to -0.53) for NBA-ADG, -0.35 to -0.66 (-0.42 to -0.45) for NBA-WT, 0.12 to 0.04 (0.12 to 0.16) for NBD-ADG, and 0.11 to 0.05 (0.11 to 0.22) for NBD-WT. Genomic selection in pigs reduced heritabilities and emphasized the antagonistic relationship that are under strong selection. Heritabilities estimated from ssGBLUP declined more than those by BLUP while changes in the genetic correlations were smaller and more gradual by ssGBLUP. Differences between ssGBLUP and BLUP could be caused by genomic pre-selection unaccounted for by BLUP.

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Model comparisons and genetic parameter estimates of growth and the Kleiber ratio in Shal sheep

Archives Animal Breeding ◽

10.7482/0003-9438-56-026 ◽

2013 ◽

Vol 56 (1) ◽

pp. 264-275 ◽

Cited By ~ 1

Author(s):

H. Mohammadi ◽

M. M. Shahrebabak ◽

H. M. Shahrebabak ◽

A. Bahrami ◽

M. Dorostkar

Keyword(s):

Maternal Effects ◽

Growth Traits ◽

Genetic Parameter ◽

Average Daily Gain ◽

Genetic Correlations ◽

Genetic Effects ◽

Parameter Estimates ◽

Phenotypic Variance ◽

Kleiber Ratio ◽

Lamb Growth

Abstract. Genetic and phenotypic parameters were estimated for lamb growth traits for the Shal sheep using an animal model. Data on lamb growth performance were extracted from available performance records at the Shal sheep Station in Qazvin, Iran. Studied traits were body weights of lambs at birth (BW), at 3 months of age as weaning weight (WW), 6 months weight (6MW), 9 months weight (9MW), yearling weight (YW), average daily gain from birth to weaning (ADG) and Kleiber ratio from birth to weaning (KR). Significant random effects for each trait were determined by fitting additive direct genetic effects, additive maternal effects, covariance between additive direct and additive maternal effects, maternal permanent environmental and maternal temporary environmental (common litter) effects under twelve animal models. Univariate analyses were carried out under the most appropriate model, determined by AIC test. Direct heritability estimates for BW, WW, ADG, KR, 6MW, 9MW and YW were 0.13, 0.19, 0.18, 0.05, 0.16, 0.18 and 0.19, respectively. Maternal additive genetic effects were fitted only for BW and WW; corresponding estimates of 0.12 and 0.10 obtained for maternal heritability of BW and WW, respectively. Maternal permanent environmental effects have low contribution in expression of KR and lead to estimates of 0.06 and 0.06 for maternal permanent environmental variance as a proportion of phenotypic variance (c2) of these traits, respectively. All pre-weaning traits, except KR, were affected by litter effects. The magnitude of ratio of common litter variance to phenotypic variance (l2) was 0.05, 0.12 and 0.14 for BW, WW and ADG, respectively. Direct genetic correlations were positive and ranged from 0.09 for KR-YW to 0.80 for WW-ADG; phenotypic ones ranged from 0.18 for KR-YW to 0.87 for WW-ADG.

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Residual feed intake and relationships with performance of Nellore cattle selected for post weaning weight

Revista Brasileira de Zootecnia ◽

10.1590/s1516-35982011000400030 ◽

2011 ◽

Vol 40 (4) ◽

pp. 929-937 ◽

Cited By ~ 19

Author(s):

T. Lucila Sobrinho ◽

R.H. Branco ◽

S.F.M. Bonilha ◽

A.M. Castilhos ◽

L.A. Figueiredo ◽

...

Keyword(s):

Body Weight ◽

Standard Deviation ◽

Feed Intake ◽

Average Daily Gain ◽

Residual Feed Intake ◽

Feed Conversion ◽

Relative Growth ◽

Kleiber Ratio ◽

Nellore Cattle ◽

Daily Gain

The objective of this work was to evaluate performance, efficiency parameters and phenotypic correlations among measurements of energy efficiency of Nellore cattle selected for post weaning weight and classified according to residual feed intake, calculated by the difference between observed and predicted intake, based on average metabolic body weight and average daily gain. Thus, animals were classified within three groups: high (> mean + 0.5 standard deviation, less efficient); medium (±0.5 standard deviation of the mean); and low (< mean - 0.5 standard deviation, more efficient) residual feed intake. No differences were observed at initial and final body weights, average daily gain and dry matter intake among groups. Animals with low residual feed intake also had greater feed efficiency, feed conversion and partial efficiency of growth and did not differ from the other animals regarding to relative growth rate and Kleiber ratio. Residual feed intake was significantly correlated to feed efficiency (-0.25), feed conversion (0.25), partial efficiency of growth (-0.37) and dry matter intake (0.16) but it did not present significant correlation with body weight (0.04), average daily gain (-0.02), relative growth rate (-0.03) and Kleiber ratio (-0.05). Significant correlations were found between feed conversion and initial body weight (0.34) and average daily gain (-0.46). Partial efficiency of growth presented significant correlation with all other efficiency parameters analyzed. Residual feed intake has high potential in productive efficiency, when compared to the other energy efficiency measurements, being independent of growth and size of the animals.

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An analysis of the variation in the lean tissue distribution of sheep

Animal Science ◽

10.1017/s0003356100010199 ◽

1982 ◽

Vol 34 (3) ◽

pp. 257-264 ◽

Cited By ~ 13

Author(s):

B. T. Wolf

Keyword(s):

Tissue Distribution ◽

Genetic Correlation ◽

Average Daily Gain ◽

Genetic Correlations ◽

Maximum Difference ◽

Lean Tissue ◽

Heritability Estimates ◽

The Relationship ◽

Daily Gain ◽

Sire Breed

ABSTRACTThe distribution of lean tissue between eight standard joints was examined in 956 crossbred lambs slaughtered at constant live weights of either 35 or 40 kg. The sire breeds used were the Dorset Down, Ile-de-France, Oldenburg, Oxford, Suffolk and Texel. Sire breed did not have a significant effect on the proportion of total carcass lean found in the higher-priced joints but did show significant differences in the proportion of total carcass lean found in individual joints, with a maximum difference of 7·7 g total lean per kg joint being recorded. Similarly, small but significant effects due to ewe age (1 to 3 years), rearing type (single, twin, triplet), sex (male castrate, female) and weight of total lean were reported for the proportion of total carcass lean found in different joints.Heritability estimates ranged from 0·07 (s.e. 008) to 0·65 (s.e. 0·16) for the proportion of total lean in the best-end neck and higher-priced joints respectively. Phenotypic standard deviations of 5·8g/kg and 17·9g/kg were reported for the proportion of total lean found in the best-end neck and the higher-priced joints respectively. The genetic correlations between the proportion of total lean in each of the higher-priced joints and the proportion of total lean in the higher-priced joints combined were positive. A genetic correlation of 017 (s.e. 0·20) was found for the relationship between average daily gain from birth to slaughter and the proportion of total lean in the higher-priced joints.

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HERITABILITIES AND GENETIC CORRELATIONS FOR ULTRASONIC BACKFAT MEASUREMENTS, GROWTH AND CARCASS TRAITS IN SWINE

Canadian Journal of Animal Science ◽

10.4141/cjas82-081 ◽

1982 ◽

Vol 62 (3) ◽

pp. 665-670 ◽

Cited By ~ 3

Author(s):

D. C. JEFFRIES ◽

R. G. PETERSON

Keyword(s):

Key Words ◽

Genetic Correlation ◽

Genetic Parameters ◽

Average Daily Gain ◽

Genetic Correlations ◽

Phenotypic Correlation ◽

Ultrasonic Measurements ◽

Yorkshire Pigs ◽

Daily Gain ◽

Season Interaction

Genetic parameters were estimated for 2403 purebred Yorkshire pigs over a 2-yr period, representing 21 sires. The traits studied included average daily gain, age adjusted to 90 kg, ultrasonic measurements of backfat at the mid-back and loin positions, total and adjusted total ultrasonic backfat and corresponding carcass backfat measurements. Least squares analyses were used to estimate and adjust for the effects of sex, year-season and sex by year-season interaction. Heritabilities and genetic correlations were calculated for all traits using both half- and full-sib estimates. Adjusted age and adjusted total ultrasonic backfat measurements were found to have the highest heritabilities of the live traits in this study. Estimates of heritability for adjusted age and adjusted total ultrasonic backfat were 0.24 ± 0.10 and 0.26 ± 0.10 based on half-sib and 0.56 ± 0.07 and 0.41 ± 0.06 from full-sib analyses. The genetic correlation between these two traits was −0.07 ± 0.28 based on the half-sib method. The total phenotypic correlation was −0.01 ± 0.02. Key words: Swine, ultrasonic backfat, heritabilities, genetic correlations

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209 Genomic selection for multiple maternal and growth traits in large white pigs using Single-Step GBLUP

Journal of Animal Science ◽

10.1093/jas/skz258.084 ◽

2019 ◽

Vol 97 (Supplement_3) ◽

pp. 42-42

Author(s):

Breno Fragomeni ◽

Zulma Vitezica ◽

Justine Liu ◽

Yijian Huang ◽

Kent Gray ◽

...

Keyword(s):

Genetic Correlation ◽

Growth Traits ◽

Computing Time ◽

Average Daily Gain ◽

Genetic Correlations ◽

Single Step ◽

Genomic Information ◽

Genomic Evaluation ◽

Large White ◽

Daily Gain

Abstract The objective of this study was to implement a multi-trait genomic evaluation for maternal and growth traits in a swine population. Phenotypes for preweaning mortality, litter size, weaning weight, and average daily gain were available for 282K Large White pigs. The pedigree included 314k individuals, of which 35,731 were genotyped for 45K SNPs. Variance components were estimated in a multi-trait animal model without genomic information by AIREMLF90. Genomic breeding values were estimated using the genomic information by single-step GBLUP. The algorithm for proven and young (APY) was used to reduce computing time. Genetic correlation between proportion and the total number of preweaning deaths was 0.95. A strong, positive genetic correlation was also observed between weaning weight and average daily gain (r = 0.94). Conversely, the genetic correlations between mortality and growth traits were negative, with an average of -0.7. To avoid computations by expensive threshold models, preweaning mortality was transformed from a binary trait to two linear dam traits: proportion and a total number of piglets dead before weaning. Because of the high genetic correlations within groups of traits, inclusion of only one growth and one mortality trait in the model decreases computing time and allows for the inclusion of other traits. Reduction in computing time for the evaluation using APY was up to 20x, and no differences in EPD ranking were observed. The algorithm for proven and young improves the efficiency of genomic evaluation in swine without harming the quality of predictions. For this population, a binary trait of mortality can be replaced by a linear trait of the dam, resulting in a similar ranking for the selection candidates.

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