Heritability and genetic correlations for stem diameter and branch characteristics in white spruce

1985 ◽  
Vol 15 (3) ◽  
pp. 494-497 ◽  
Author(s):  
R. E. Merrill ◽  
C. A. Mohn
Keyword(s):  
Rapid Growth ◽  
Genetic Correlations ◽  
Negative Relationship ◽  
Selection Procedure ◽  
Height Growth ◽  
Stem Diameter ◽  
Branch Diameter ◽  
Branch Angle ◽  
Selection For ◽  
Number Of Branches

Heritabilities were calculated for several traits in a selected population of 20-year-old Piceaglauca (Moench) Voss. The population had been modified by selection for rapid height growth at ages 12 and 18 years. Heritability estimates were moderate for branch angle and low for stem diameter, branch diameter, and number of branches per whorl. The genetic correlations among the traits indicated a negative relationship between rapid growth and desirable branch characters, although the correlations were generally small. The use of a two-stage selection procedure, selecting initially for rapid growth and subsequently for desirable branching traits, appears feasible in this population.

scholarly journals Stem Characteristics on the Lower Log of 35-Year-Old Western Redcedar Grown at Several Spacings

1997 ◽  
Vol 12 (1) ◽  
pp. 9-15 ◽  
Author(s):  
Jeffrey D. DeBell ◽  
Barbara L. Gartner
Keyword(s):  
Large Diameter ◽  
Stem Diameter ◽  
Stem Length ◽  
Thuja Plicata ◽  
Western Redcedar ◽  
Branch Diameter ◽  
University Of British Columbia ◽  
The University ◽  
Number Of Branches

Abstract Information on stem characteristics of western redcedar (Thuja plicata) grown in managed stands is quite limited. Stem characteristics are important because they influence the quality of logs and lumber produced. We measured branch diameter, number of branches, taper, and fluting severity on the first 5m log of stems grown at spacings of 1.8 to 4.6 m in a 35-yr-old spacing trial on the University of British Columbia Research Forest. Average branch diameter increased from 15 mm to 25 mm as tree spacing increased from 1.8 m to 4.6 m. Number of branches per unit of stem length was unaffected by spacing. Trees at wider spacings tended to be more tapered and have more butt swell than those at narrower spacings. At wider spacings, more trees showed fluting, and that fluting was more severe than at narrower spacings. However, most trees had no fluting or only mild fluting even at the 4.6 m spacing. Branch diameter, taper, and fluting were all related to stem diameter. Smaller diameter stems tended to have smaller branches, less taper, and were less likely to have severe fluting than large diameter stems. Branch diameter was larger at wider spacings even for trees of the same stem diameter. West. J. Appl. For. 12(1):9-14.

Selection for weaning weight in Merino sheep. 2. Correlated responses in other production characters

1965 ◽  
Vol 5 (19) ◽  
pp. 361 ◽  
Author(s):  
WA Pattie
Keyword(s):  
Milk Protein ◽  
Survival Rates ◽  
Genetic Correlations ◽  
Negative Relationship ◽  
Weaning Weight ◽  
Merino Sheep ◽  
Selection For ◽  
The Difference ◽  
Fleece Weight ◽  
Lamb Growth

The heritabilities of seven production characters of Merino Sheep and their phenotypic and genetic correlations with corrected weaning weight have been calculated using half-sib and dam-daughter correlations. Realized genetic correlations calculated from responses in Weight Plus and Weight Minus selection flocks, which showed broad agreement with these correlations, were : 17-month body weight, 0.72 ; yield, 0.22 ; clean fleece weight, 0.24 ; and staple length, 0.17. There was zero relationship with greasy fleece weight and crimps per inch, and a large negative relationship between folds and high weaning weight. There were strong phenotypic correlations between lamb growth and milk production through the total weight of milk protein produced. The lamb's genotype was the most important contributor to the difference in weaning weight between the flocks. There were no differences in reproductive performance or survival rates between the flocks but twice as many twin rams and 20 per cent more twin ewes were mated in the Weight Minus flock over the selection period.

Genotype × environment interaction in Norway spruce involving three levels of genetic control: seed source, clone mixture, and clone

1988 ◽  
Vol 18 (9) ◽  
pp. 1172-1181 ◽  
Author(s):  
B. G. Bentzer ◽  
G. S. Foster ◽  
A. R. Hellberg ◽  
A. C. Podzorski
Keyword(s):  
Genetic Control ◽  
Genetic Correlations ◽  
Negative Relationship ◽  
Height Growth ◽  
Regression Coefficients ◽  
Environment Interaction ◽  
Control Seed ◽  
Genotype Environment Interaction ◽  
The Stability ◽  
Average Individual

A total of 913 Piceaabies (L.) Karst. clones was tested for height at ages 1 and 5 in two series on six and three locations, respectively, in Sweden. The genotype × environment interaction was studied for three levels of genetic control, i.e., seedling checklot, clone mixture, and clone. Stability of all three was estimated using regression coefficients. The alternative method, genetic correlation between locations, was also used to measure stability. Height differences among seedling checklots and among clones were substantial at age 5, while the variation among clone mixtures was not significant. Genotype × environment interaction was found to be significant for clones and accounted for an average of 2.1% of the total variance at age 5. No significant interaction was found between mixtures and locations. The genotype × environment interaction for seedling checklots was not significant and accounted for 0.5% of the total variation at age 5. The stability of seedling checklots at age 5 was high. For the clone mixtures, stability was found to be about average. Individual clones showed wide variation in stability. There was an apparent negative relationship between clone performance and stability. Genetic correlations indicated close agreement between locations in the ranking of clones for height growth.

Identifying Measurement Invariant Item Sets in Cross-Cultural Settings Using an Automated Item Selection Procedure

Methodology ◽  
2018 ◽  
Vol 14 (4) ◽  
pp. 177-188 ◽  
Author(s):  
Martin Schultze ◽  
Michael Eid
Keyword(s):  
Measurement Invariance ◽  
Optimal Solution ◽  
Selection Procedure ◽  
Cross Cultural ◽  
Item Selection ◽  
Ant System ◽  
Item Quality ◽  
Ant System Algorithm ◽  
Selection For ◽  
Selection Of

Abstract. In the construction of scales intended for the use in cross-cultural studies, the selection of items needs to be guided not only by traditional criteria of item quality, but has to take information about the measurement invariance of the scale into account. We present an approach to automated item selection which depicts the process as a combinatorial optimization problem and aims at finding a scale which fulfils predefined target criteria – such as measurement invariance across cultures. The search for an optimal solution is performed using an adaptation of the [Formula: see text] Ant System algorithm. The approach is illustrated using an application to item selection for a personality scale assuming measurement invariance across multiple countries.

129 Genomic Relationship Between PRRSV Wild-type Infection and PRRSV Vaccination for Antibody Response and Reproductive Performance

2021 ◽  
Vol 99 (Supplement_1) ◽  
pp. 18-18
Author(s):  
Leticia P Sanglard ◽  
Felipe Hickmann ◽  
Yijian Huang ◽  
Kent A Gray ◽  
Daniel Linhares ◽  
...  
Keyword(s):  
Antibody Response ◽  
Reproductive Performance ◽  
Genetic Correlations ◽  
Clinical Signs ◽  
Respiratory Syndrome Virus ◽  
Wild Type ◽  
Large White ◽  
Selection For ◽  
Indicator Trait ◽  
Type Infection

Abstract Immunoglobulin G antibody response, measured as sample-to-positive (S/P) ratio, to Porcine Reproductive and Respiratory Syndrome virus (PRRSV) has been proposed as an indicator trait for improved reproductive performance in PRRSV-infected purebred sows and PRRSV-vaccinated crossbred gilts. In this study, we investigated the genetic correlations (rg) of S/P ratio following a PRRSV outbreak and PRRSV-vaccination with performance in non-exposed and PRRSV-exposed sows. PRRSV outbreak phase was defined based on previously described methodologies after the detection of typical clinical signs of PRRSV infection. 541 Landrace sows had S/P ratio measured at ~54 days after the beginning of the PRRSV outbreak (S/Poutbreak), and 906 Landrace x Large White naïve F1 gilts had S/P ratio measured at ~50 days after vaccination with a commercial modified live PRRSV vaccine (S/PVx). 711 and 428 Landrace sows had reproductive performance recorded before and during the PRRSV outbreak, respectively. 811 vaccinated F1 animals had farrowing performance for up to 3 parities. All animals were genotyped for ~28K SNPs. The estimate of rg of S/Poutbreakwith S/PVx was high (rg±SE = 0.72±0.18). Estimates of rg of S/Poutbreak with reproductive performance in F1 sows were low to moderate, ranging from 0.05±0.23 (number stillborn) to 0.30±0.20 (total number born). Estimates of rg of S/PVxwith reproductive performance in non-infected purebred sows were moderate and favorable with number born alive (0.50±0.23), but low (0 to -0.11±0.23) with litter mortality traits. Estimates of rg of S/PVx were moderate and negative (-0.47±0.18) with the number of mummies in PRRSV-infected purebred sows and low with other traits (-0.29±0.18 for total number born to 0.05±0.18 for number stillborn). These results indicate that selection for antibody response following a PRRSV outbreak collected in purebred sows and to PRRSV vaccination collected in commercial crossbred gilts may increase litter size of non-infected and PRRSV-exposed purebred and commercial crossbred sows.

Selection for components of efficient lean growth rate in pigs 2. Selection pressure applied and direct responses in a Landrace herd

1994 ◽  
Vol 59 (2) ◽  
pp. 263-269 ◽  
Author(s):  
N. D. Cameron ◽  
M. K. Curran
Keyword(s):  
Growth Rate ◽  
Genetic Correlations ◽  
Correlated Response ◽  
Selection Line ◽  
Control Line ◽  
Direct Response ◽  
Lean Growth ◽  
Ad Libitum ◽  
Selection For ◽  
Ad Libitum Feeding

AbstractResponses to divergent selection for lean growth rate with ad-libitum feeding (LGA), for lean food conversion (LFC) and for daily food intake (DFI) in Landrace pigs were studied. Selection was practised for four generations with a generation interval ofl year. A total of 2642 pigs were performance tested in the high, low and control lines, with an average of 37 boars and 39 gilts performance tested per selection line in each generation. The average within-line inbreeding coefficient at generation four was equal to 0·04. There was one control line for the DFI and LFC selection groups and another control line for the LGA selection group. Animals were performance tested in individual pens with mean starting and finishing weights of 30 kg and 85 kg respectively with ad-libitum feeding. The selection criteria had phenotypic s.d. of 32, 29 and 274 units, for LGA, LFC and DFI, respectively, and results are presented in phenotypic s.d.Cumulative selection differentials (CSD) were 5·1, 4·5 and 5·5 phenotypic s.d. for LGA, LFC and DFI, respectively. Direct responses to selection were 1·4,1·1 and 0·9 (s.e. 0·20) for LGA, LFC and DFI. In each of the three selection groups, the CSD and direct responses to selection were symmetric about the control lines. The correlated response in LFC (1·1, s.e. 0·19) with selection on LGA was equal to the direct response in LFC. In contrast, the direct response in LGA was greater than the correlated response (0·7, s.e. 0·18) with selection on LFC. There was a negative correlated response in DFI (-0·6, s.e. 0·18) with selection on LFC, but the response with selection on LGA was not significant (0·2, s.e. 0·16).Heritabilities for LGA, LFC and DFI ivere 0·25, 0·25 and 0·18 (s.e. 0·03), when estimated by residual maximum likelihood, with common environmental effects of 0·12 (s.e. 0·02). Genetic correlations for LFC with LGA and DFI were respectively positive (0·87, s.e. 0·02) and negative (-0·36, s.e. 0·09), while the genetic correlation between DFI and LGA was not statistically different from zero, 0·13 (s.e. 0·10). Selection on components of efficient lean growth has identified LGA as an effective selection objective for improving both LGA and LFC, without a reduction in DFI.

Genetic variation in fatty acid composition of subcutaneous fat in cattle

2013 ◽  
Vol 53 (2) ◽  
pp. 129 ◽  
Author(s):  
M. J. Kelly ◽  
R. K. Tume ◽  
S. Newman ◽  
J. M. Thompson
Keyword(s):  
Fatty Acids ◽  
Genetic Variation ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Acid Composition ◽  
Saturated Fatty Acids ◽  
Genetic Correlations ◽  
Subcutaneous Fat ◽  
Monounsaturated Fatty Acids ◽  
Selection For

Genetic parameters were estimated for fatty acid composition of subcutaneous beef fat of 1573 animals which were the progeny of 157 sires across seven breeds grown out on pasture and then finished on either grain or grass in northern New South Wales or in central Queensland. There was genetic variation in individual fatty acids with estimates of heritability for the proportions of C14 : 0, C14 : 1c9, C16 : 0, C16 : 1c9, C18 : 0 and C18 : 1c9 fatty acids in subcutaneous beef fat of the order of 0.4 or above. Also substantial correlations between some fatty acids were observed. Genetic correlations between fatty acids and fat depth at the P8 site suggested that much of the genetic variation in fatty acid composition was related to changes in fatness. Selection for decreased fatness resulted in decreased proportions of C18 : 1c9 with concomitant increases in C18 : 0, C14 : 0 and C16 : 0. This suggested that selection for decreased fatness at a given weight will result in a decrease in the proportions of monounsaturated fatty acids in the subcutaneous fat in the carcass with a corresponding increase in the proportions of saturated fatty acids.

scholarly journals Stimuli Selection Criteria for the Experiment “Visual Perception of Imitative Words in Native and Non-Native Language by the Method Lexical Decision”

Discourse ◽  
2020 ◽  
Vol 6 (5) ◽  
pp. 97-112
Author(s):  
M. A. Flaksman ◽  
Yu. V. Lavitskaya ◽  
Yu. G. Sedelkina ◽  
L. O. Tkacheva
Keyword(s):  
Visual Perception ◽  
Lexical Decision ◽  
Native Language ◽  
Material Selection ◽  
Selection Procedure ◽  
Parts Of Speech ◽  
Clear Cut ◽  
Gradual Loss ◽  
Etymological Dictionary ◽  
Selection For

Introduction. The present article is aiming to describe the procedure of stimuli selection for the psycho-semantic experiment on visual perception of imitative words in native (Russian) and non-native language (English). The methodology of the experiment is predominantly based on the implementation of the “lexical decision” method. Thus, the aim of the article is to verify the procedure of and to define clear-cut criteria for the material selection. In particular, we introduce indicating de-iconization stage of imitative words as an important criterion for data pre-selection. De-iconization is a gradual loss of an iconic sound-sense link in an imitative word due to the parallel impact of regular sound changes and semantic shifts.Methodology and sources. The  research  methodology  is  based  on  the  works  ofS. V. Voronin who is the founder of phonosemantics as a linguistic discipline inRussia, as well as on works of his followers (including a co-author of this paper, M. A. Flaksman). The article is also based on the methodology of research on phonotactics. The authors also use psycho-semantic methods such as the method of lexical decision. The main sources of stimuli selection are The Russia Etymological Dictionary by M. Vasmer, The Oxford English Dictionary, the frequency dictionaries by O. N. Liashevskaya and S. A. Sharov. The classification of imitative words according to their de-iconization stages was done by the method of the diachronic evaluation of the imitative lexicon.Results and discussion. As a result of a rigorous selection procedure described in the article the authors arrived on 128 stimuli (an even number (64 + 64) of words and quasiwords). The quasi-words are coined according to phonotactic rules and made according to the same pattern as the corresponding words. The group of real words is constituted of two sub-groups: 32 imitative words and 32 non-imitative words. The words from these two subgroups are homomorphous – they have the same number of syllables, frequency and belong to the same parts of speech. Imitative words include onomatopoeic and soundsymbolic words of different sub-classes and de-iconization stages. The combination of the material selection methods discussed in this paper (especially, the introduction of the distinction of imitative words according to their de-iconization stage) is aiming at facilitating the experiment procedure as well as eliminating the chance factors.Conclusion. The stimuli selection for the psycholinguistic experiment based on the procedure introduced in this paper allows to establish the existing patterns of the systematic function of human brain in the process of visual perception of imitative words on different de-iconization stages.

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