Age trends in genetic parameters of wood density in young Norway spruce

Age trends of phenotypic, environmental, and additive genetic variance and heritability were estimated for overall density and its components earlywood and latewood densities and latewood proportion. The objective was to acquire information for both individual and cumulated rings from ring number 3 to 12 counted from the pith. Age-age correlations were calculated for cumulated density traits only. The wood density data were obtained with X-ray analysis of increment cores from 47 open-pollinated families of Norway spruce (Picea abies (L.) Karst.). The families had earlywood and latewood with significant differences in density for individual and cumulated rings and consequently for overall density. The latewood proportion had significant family variation for cumulated rings but not for all individual rings. Large fluctuations in environmental variance caused fluctuations in heritability estimates for successive rings. A strong decrease in environmental variance for all cumulated traits, especially from ring 3 to 5, resulted in a steady increase in heritability estimates. The latewood density had the highest heritability estimates and latewood proportion the lowest for both individual and cumulated rings. Overall density and the cumulated components at cambial age 12 showed strong genetic correlations with their respective traits at all younger ages.

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Estimation of genetic parameters and comparison of random regression animal and sire models of production traits in the first three lactations of Iranian Holsteins

Biotechnology in Animal Husbandry ◽

10.2298/bah1402261m ◽

2014 ◽

Vol 30 (2) ◽

pp. 261-279 ◽

Cited By ~ 1

Author(s):

A. Mohammadi ◽

S. Alijani

Keyword(s):

Milk Fat ◽

Genetic Parameters ◽

Additive Genetic Variance ◽

Genetic Correlations ◽

Random Regression ◽

Lactation Period ◽

Production Traits ◽

Environmental Variance ◽

In The Beginning ◽

Residual Variances

This study was conducted to compare of random regression (RR) animal and sire models for estimation of the genetic parameters for production traits of Iranian Holstein dairy cows. For this purpose, the test day records were used belonged to first three lactations of cows and for, milk, fat and protein yields traits where, collected from 2003 to 2010, by the national breeding center of Iran. The genetic parameters were estimated using restricted maximum likelihood algorithm. To compare the model, different criterion -2logL value, AIC, BIC and RV were used for considered traits. Residual variances were considered homogeneous over the lactation period. Obtained results showed that additive genetic variance was highest in the beginning and end lactation and permanent environmental variance was highest in beginning of lactation than other lactation period. Heritabilities estimate for milk, fat and protein yields by RR animal and sire models were found to be lowest during early lactation (0.05, 0.04 and 0.07; 0.05, 0.19 and 0.13; 0.14, 0.19 and 0.15, for milk, fat and protein yields and in first, second and third lactation respectively). However, estimated heritabilities during lactation did not vary among different order Legendre polynomials, and also between RR animal and sire models. The variation in genetic correlations estimate in the RR animal and sire models was larger in the first lactation than in the second and third lactations. Thus, based on the results obtained, it can be inferred that the RR animal model is better for modeling yield traits in Iranian Holsteins.

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Genetic parameter estimates (full sib and half sib analysis) of fertility and hatchability in two strains of Rhode Island chickens

Nigerian Journal of Animal Production ◽

10.51791/njap.v38i1.706 ◽

2021 ◽

Vol 38 (1) ◽

pp. 14-22

Author(s):

M. Orunmuyi ◽

I. A. Adeyinka ◽

O.O Oni

Keyword(s):

Rhode Island ◽

Additive Genetic Variance ◽

Genetic Parameter ◽

Genetic Correlations ◽

Reproductive Traits ◽

Parameter Estimates ◽

Phenotypic Correlations ◽

Poultry Breeding ◽

Genetic And Phenotypic Correlations ◽

Heritability Estimates

A study was conducted to estimate the genetic parameters of fertility and hatchability in two strains of Rhode Island Red (RIR) Chickens denoted as Strain A and Strain B respectively using the full-sib (sire +dam variance) and maternal half-sib (dam variance) components. The birds were obtained from the selected populations of RIR Chickens kept at the poultry breeding programme of National Animal Production Research Institute, Shika, Zaria, Nigeria. Settable eggs were collected from mating 28 cocks to 252 hens in a ratio of 1cock:9 hens from each strain. Eggs were pedigreed according to sire and dam. Results showed that values obtained for number of egg set (EGGSET), number of fertile eggs (NFERT), number of hatched chicks (NHATCH), percentage of chicks hatched from total eggs set (PHATCH) and percentage of chicks hatched from fertile eggs (PHATCHBL) were all higher in strain A than strain B. Heritability estimates obtained from the full-sib and maternal half-sib analysis ranged from medium to high for the two strains (0.24-0.96). The maternal half sib estimates were higher (0.40-0.96) than the estimates obtained from full sibs (0.24- 0.48). Genetic and phenotypic correlations obtained for both strains were positive and similar regardless of method of estimation. Genetic correlations between EGGSET and PFERT were low in strain A using both full-sib and maternal half-sib analyses (0.09-0.14). Phenotypic correlations between EGGSET and PFERT, PHATCH and PHATCHBL were also low in both strains and regardless of method of analyses. Moderate to high heritability estimates suggest that genetic improvement can be obtained by selection of these reproductive traits. The full-sib analysis for estimating heritability will be preferred since it is assumed that only additive genetic variance contributes to the covariance between family members.

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Optimum selection age for wood density in loblolly pine

Canadian Journal of Forest Research ◽

10.1139/x02-064 ◽

2002 ◽

Vol 32 (8) ◽

pp. 1393-1399 ◽

Cited By ~ 17

Author(s):

D P Gwaze ◽

K J Harding ◽

R C Purnell ◽

F E Bridgwater

Keyword(s):

Linear Relationship ◽

Wood Density ◽

Genetic Correlations ◽

Core Density ◽

Individual Tree ◽

Phenotypic Correlations ◽

Age Related ◽

Optimum Selection ◽

Heritability Estimates ◽

Optimum Selection Age

Genetic and phenotypic parameters for core wood density of Pinus taeda L. were estimated for ages ranging from 5 to 25 years at two sites in southern United States. Heritability estimates on an individual-tree basis for core density were lower than expected (0.200.31). Ageage genetic correlations were higher than phenotypic correlations, particularly those involving young ages. Ageage genetic correlations were high, being greater than 0.75. Ageage genetic correlations had a moderately linear relationship, while ageage phenotypic correlations had a strong linear relationship with natural logarithm of age ratio. Optimum selection age for core density was estimated to be 5 years when calculations were based on both genetic and phenotypic correlations. However, age 5 was the youngest examined in this study and optimum selection age may be younger than 5. Generally, the optimum selection age was robust to changes in breeding phase and assumptions concerning age-related variation in heritability estimates. Early selection for core density would result in a correlated increase in earlywood density but little progress in latewood density or latewood proportion at maturity.

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Genetic parameters of body weight in japanese quails (Coturnix japonica Temminck & Schlegel, 1849) in the Philippines

Annals of Tropical Research ◽

10.32945/atr4216.2020 ◽

2020 ◽

pp. 72-78

Author(s):

Angie Poliquit

Keyword(s):

Body Weight ◽

Genetic Parameters ◽

Additive Genetic Variance ◽

Genetic Correlations ◽

The Philippines ◽

Japanese Quails ◽

Randomized Design ◽

Body Weights ◽

Reproduction Traits ◽

Heritability Estimates

The establishment of breeding and selection programs to improve the genetic potential of poultry necessitates estimation of genetic parameters for different production and reproduction traits, Restricted maximum likelihood (REML) software was used to estimate the heritability (h2) and genetic correlations (r) of body weights in Japanese quails (C. japonica) from hatch to fifth week of age. A total of 224 Japanese quails composed of 56 males and 168 females arranged in a Completely Randomized Design (CRD) served as the base population. Body weight records, measured weekly from hatch to fifth week, were utilized to estimate the genetic parameters. Heritability estimates were 0.093±0.004, 0244±0.010, 0.031±0.001, 0082±0.004, 0325±0.016 and 0.025±0.001 for body weights at hatch (BW0), first week (BW1), second week (BW2), third week (BW3), fourth week (BW4) and fifth week (BW5), respectively. Low heritability estimates depict a decrease in additive genetic variance as the generations progressed. Negative genetic correlation was found between BW0 and BW4 (r=- 0.027). The significant positive genetic correlations of BW0 with BW1 (r=0.271); BW1 with BW2 (r=0.270), BW3 (r=0.294), BW4 (r=0.255), and BW5 (r=0.243); BW2 with BW3 (r=0.561), BW4 (r=0.649), and BW5 (r=0.503); BW3 with BW4 (r=0.726), and BW5 (r=0.551); and BW4 with BW5 (r=0.689) are expected to bring correlated responses in the other traits.

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Host Genetics of Response to Porcine Reproductive and Respiratory Syndrome in Sows: Reproductive Performance

Frontiers in Genetics ◽

10.3389/fgene.2021.707870 ◽

2021 ◽

Vol 12 ◽

Cited By ~ 1

Author(s):

Felipe M. W. Hickmann ◽

José Braccini Neto ◽

Luke M. Kramer ◽

Yijian Huang ◽

Kent A. Gray ◽

...

Keyword(s):

Reproductive Performance ◽

Additive Genetic Variance ◽

Genetic Correlations ◽

Reproductive Traits ◽

The Other ◽

Nucleotide Polymorphisms ◽

Host Genetics ◽

Other Hand ◽

Selection For ◽

Heritability Estimates

Porcine Reproductive and Respiratory Syndrome (PRRS) is historically the most economically important swine disease worldwide that severely affects the reproductive performance of sows. However, little is still known about the genetic basis of reproductive performance in purebred herds during a PRRS outbreak through the comparison of maternal and terminal breeds. Thus, the objective of this work was to explore the host genetics of response to PRRS in purebred sows from two breeds. Reproductive data included 2546 Duroc and 2522 Landrace litters from 894 and 813 purebred sows, respectively, which had high-density genotype data available (29,799 single nucleotide polymorphisms; SNPs). The data were split into pre-PRRS, PRRS, and post-PRRS phases based on standardized farrow-year-week estimates. Heritability estimates for reproductive traits were low to moderate (≤0.20) for Duroc and Landrace across PRRS phases. On the other hand, genetic correlations of reproductive traits between PRRS phases were overall moderate to high for both breeds. Several associations between MARC0034894, a candidate SNP for response to PRRS, with reproductive performance were identified (P-value < 0.05). Genomic analyses detected few QTL for reproductive performance across all phases, most explaining a small percentage of the additive genetic variance (≤8.2%, averaging 2.1%), indicating that these traits are highly polygenic. None of the identified QTL within a breed and trait overlapped between PRRS phases. Overall, our results indicate that Duroc sows are phenotypically more resilient to PRRS than Landrace sows, with a similar return to PRRS-free performance between breeds for most reproductive traits. Genomic prediction results indicate that genomic selection for improved reproductive performance under a PRRS outbreak is possible, especially in Landrace sows, by training markers using data from PRRS-challenged sows. On the other hand, the high genetic correlations with reproductive traits between PRRS phases suggest that selection for improved reproductive performance in a clean environment could improve performance during PRRS, but with limited efficiency due to their low heritability estimates. Thus, we hypothesize that an indicator trait that could be indirectly selected to increase the response to selection for these traits would be desirable and would also improve the reproductive performance of sows during a PRRS outbreak.

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Long-Term Wood Micro-Density Variation in Alpine Forests at Central México and Their Spatial Links with Remotely Sensed Information

Forests ◽

10.3390/f11040452 ◽

2020 ◽

Vol 11 (4) ◽

pp. 452 ◽

Cited By ~ 1

Author(s):

A. Correa-Díaz ◽

A. Gómez-Guerrero ◽

J. J. Vargas-Hernández ◽

P. Rozenberg ◽

W. R. Horwath

Keyword(s):

Wood Density ◽

Elevation Gradient ◽

Remotely Sensed ◽

High Elevation ◽

Density Variation ◽

Distribution Functions ◽

Cumulative Distribution ◽

Cambial Age ◽

Latewood Density ◽

High Elevation Forests

Ongoing climate variability strongly affects high-elevation forests, influencing the wood formation process (e.g., xylogenesis). Furthermore, spatio-temporal studies to establish links of wood properties and tree performance are needed. Using linear mixed-effects models, empirical cumulative distribution functions, and spatial analysis, we explore time trends and space connections of wood density of Pinus hartwegii Lindl. to remotely sensed variables (Moderate Resolution Imaging Spectro-radiometer MODIS-derived) in two high-elevation forests in México, Tláloc (TLA) and Jocotitlán (JOC) Mountains. Results indicated that elevation and cambial age effects are important factors explaining wood density variation. Minimum earlywood—MID, average—AVE, and maximum latewood density—MXD were statistically similar between mountains (p > 0.05), but TLA showed a significant increase in MID over time with higher values after 1950. Wood density values and spatial correlations were site-dependent with TLA exhibiting the highest correlations between MXD and the Normalized Difference Vegetation Index (NDVI) of the spring season (r = 0.59, p < 0.05). Overall, correlations to remotely sensed information were positive with MXD, negative for MID and divergent for AVE. Historical temperature defines MID along the elevation gradient, while MXD was related to soil moisture only at low-elevation sites where soils are deeper. We found that two high-elevation forests, 115 km away from each other, with similar climate, soil, and vegetation, behaved differently regarding their xylogenesis, indicating the potential of using the link between wood micro-density and remotely sensed information to understand forest response to climate change effects.

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Genetic studies on growth, reproduction and wool productiontraits in Harnali sheep

Indian Journal of Animal Research ◽

10.18805/ijar.10984 ◽

2016 ◽

Author(s):

SPACE Lalit ◽

Z. S. Malik ◽

D. S. Dalal ◽

C. S. Patil ◽

S. P. Dahiya

Keyword(s):

Body Weight ◽

Growth Traits ◽

Additive Genetic Variance ◽

Genetic Correlations ◽

Fibre Diameter ◽

Reproductive Traits ◽

Phenotypic Correlation ◽

Reproduction Traits ◽

Heritability Estimates ◽

Fleece Weight

Data on growth, reproduction and wool traits of 1603 Harnali sheep maintained at Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar over a period of 22 years (1992-2013) were utilized for genetic analysis. The overall least squares mean for birth weight (BW), weaning weight (WW), six month body weight (SMW), age at first lambing (AFL), weight at lambing (WL), average lambing interval (ALI), greasy fleece weight (GFW), staple length (SL) and Fibre diameter (FD) were estimated as 3.35±0.02 kg, 12.41±0.08 kg, 16.30±0.12 kg, 707.05±2.07 days, 26.91±0.10 kg and 402.85±2.40 days, 1.62±0.02 kg, 5.65±0.03 cm and 25.85±0.07 μ, respectively. The effect of year of birth, sex of lamb and dam's weight at lambing were significant for all growth traits. The effect of year of birth and dam's weight at lambing were significant for all reproduction traits and GFW. No definite trend was observed over the years for body weights and reproductive traits. The effect of sex was significant for early growth traits. The heritability estimates were moderate for all the growth traits with high genetic correlations of BW and WW with SMW. Reproduction traits had lower estimates of heritability which indicated presence of lower additive genetic variance for these traits. Heritability estimates for studied wool traits were moderate to high. Positive genetic and phenotypic correlation of BW and WW with six month body weight and grease fleece weight indicated that selection for six month body weight would increase body weight and grease fleece weight.

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Wood density as a screening trait for drought sensitivity in Norway spruce

Canadian Journal of Forest Research ◽

10.1139/cjfr-2013-0209 ◽

2014 ◽

Vol 44 (2) ◽

pp. 154-161 ◽

Cited By ~ 34

Author(s):

S. Rosner ◽

J. Světlík ◽

K. Andreassen ◽

I. Børja ◽

L. Dalsgaard ◽

...

Keyword(s):

Norway Spruce ◽

Wood Density ◽

Heat Waves ◽

Drought Event ◽

Pressure Potential ◽

Data Set ◽

Cambial Age ◽

Hydraulic Vulnerability ◽

Southern Norway ◽

The Impact

We linked hydraulic vulnerability in Norway spruce (Picea abies (L.) Karst.) trunkwood with different cambial age to wood density and applied the findings on annual density variations in healthy and declining trees from southern Norway during 1990 to 2010. We hypothesized that drought stress due to the 2003 or 2006 European heat waves were the triggers for tree decline and focused analyses on the structure of wood that was produced after, as well as before, signs of stress, i.e., when decreases in height or diameter growth were visible. In the data set comprising previously published and new measurements, P50, i.e., the pressure potential necessary to induce a 50% loss in hydraulic conductivity, was negatively related to wood density. Declining trees produced wider annual rings with lower density than vigorous trees before their radial and height increment started to decline in 2003 or 2006. Trees that produced low-density wood under favorable water availability were more stressed by a sudden drought event because of higher P50 values in their sapwood. Due to the strong genotypic relationship between wood density and growth, we suggest that spruce trees selected for fast growth might experience limited hydraulic performance under the impact of extreme heat waves.

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Intratree and intertree variation in selected wood quality characteristics of European oak (Quercuspetraea and Quercusrobur)

Canadian Journal of Forest Research ◽

10.1139/x94-235 ◽

1994 ◽

Vol 24 (9) ◽

pp. 1818-1823 ◽

Cited By ~ 20

Author(s):

S.Y. Zhang ◽

G. Nepveu ◽

R. Eyono Owoundi

Keyword(s):

Total Variation ◽

Wood Density ◽

Wood Quality ◽

Ring Width ◽

Relative Magnitude ◽

Tree Age ◽

Cambial Age ◽

Latewood Density ◽

European Oak ◽

Intratree Variation

Twenty-three trees of European oak (Quercuspetraea (Matt) Liebl. and Quercusrobur L.) were collected from northeastern France to study intratree and intertree variation in the following characteristics: (i) wood density as well as earlywood density and latewood density; (ii) various types of wood shrinkage; and (iii) ring width and its components. Both intratree variation and intertree variation in the three characteristics are significant, but intertree variation is generally smaller. However, the relative magnitude of intertree variation varies with characteristic: intertree variation accounts for about 40% of the total variation in radial, tangential, and volumetric wood shrinkage, 32.5% of the total variation in ring width, and 12.6% of the total variation in wood density. Furthermore, the intertree variation is closely and positively related to the intratree variation: among the three characteristics studied, both intertree variation and intratree variation were highest for ring width and its components, and lowest for wood density and its components. In addition, intratree variation increased remarkably with increasing tree age in these species. In general, intratree variation in wood density and wood shrinkage depends more on cambial age than on ring width. The present study, together with the information available so far, suggests that the quality of European oak wood could be significantly improved.

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