scholarly journals Optimizing Selection for Yield Using Selection Index

Zuriat ◽  
2015 ◽  
Vol 13 (1) ◽  
Author(s):  
Sugiono Moeljopawiro
Keyword(s):  
Selection Index ◽  
Economic Value ◽  
Selection Procedure ◽  
Panicle Length ◽  
Diallel Crosses ◽  
Individual Trait ◽  
Selection Indices ◽  
Selection For ◽  
Grain Width ◽  
Half Diallel

An experiment was conducted to construct selection indices for yield. F2 populations of half diallel crosses involving six cultivars were analyzed to calculate phenotypic and additive genetic variances and covariances which were used to construct selection indices. Results of the selection index indicated that selection applied to several traits simultaneously was more efficient than selection based on an individual trait or a combination of only one or two traits. However, the choice of traits to be included in a selection index should be determined by their economic value and Index involving panicle length, grain length, and grain width, was a promising index in this study. A selection index properly constituted can be used to improve the selection procedure, once homozygousity is assured.

Effect of sampling errors on efficiency of selection indices. 2. Use of information on associated traits for improvement of a single important trait

1976 ◽  
Vol 23 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Jill Sales ◽  
W. G. Hill
Keyword(s):  
Selection Index ◽  
Heritability Estimate ◽  
Parameter Estimates ◽  
Response To Selection ◽  
Sampling Errors ◽  
Estimation Of Parameters ◽  
Selection Indices ◽  
Important Trait ◽  
Selection For ◽  
Efficiency Of Selection

SUMMARYAn analysis is undertaken of the effect of errors in estimates of parameters on the response to selection for an economically important trait (trait 1) when one or more additional traits are added in a selection index. The detailed analysis is confined to one additional trait (trait 2) which contributes useful information unless the genetic and phenotypic regressions of trait 1 on trait 2 are equal.If there are errors in parameter estimates the extra response obtained by including trait 2 will usually be over-predicted. When trait 2 actually contributes no useful information the predicted benefit equals the real loss in efficiency from its inclusion.The loss in efficiency from poor estimation of parameters, whether or not the second trait makes a contribution, is roughly one-quarter of the squared coefficient of variation of a heritability estimate of trait 1 in the same experiment.

scholarly journals 215 Selection response for meat quality and carcass composition in commercial pigs using crossbred and purebred traits as predictors

2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 45-45
Author(s):  
Emmanuel A Lozada-Soto ◽  
Justin Fix ◽  
Clint Schwab ◽  
Francesco Tiezzi
Keyword(s):  
Meat Quality ◽  
Lower Cost ◽  
Economic Value ◽  
Cost Effective ◽  
Selection Response ◽  
Carcass Composition ◽  
Direct Selection ◽  
Selection Indices ◽  
Breeding Objectives ◽  
Selection For

Abstract Meat quality (MQ) and carcass composition (CC) are traits with high economic value, but their phenotyping costs makes direct selection for these traits economically unsustainable. Evaluation of traits with lower cost of collection in crossbred (CB) and purebred (PB) animals for use in selection for MQ and CC remains limited. The aim of this study was to measure the response to selection of economically important MQ and CC traits using different selection indices built on cost-effective correlated traits. Phenotypic and genomic information (using 60K SNP chips) was collected for three-way CB (n = 1227 to 5117 phenotyped, n = 1252 genotyped) and PB (n = 3,251 phenotyped, n = 1035 genotyped) Duroc animals belonging to 28 paternal half-sib families. The three breeding objectives (for which response was estimated) were intramuscular fat (IMF), slice shear force (SSF), and loin weight (LW). In total 7 different selection indices (A-G) were used to estimate the selection response for each breeding objective (Table 1). Heritability and genetic correlation parameters for all traits were estimated using GIBBS1F90. Selection response was obtained as expected response per generation weighed by the accuracy of breeding values estimated from a 4-fold cross validation, where animals were grouped based on sire relatedness. For all three breeding objectives, the index which provided best selection response was A (direct selection), with values of 0.35%, -0.72 kg, and 0.85 kg for IMF, SSF, and LW respectively. The index which provided the second-best selection response was B (color and pH traits) for all three breeding objectives, with values of 0.15%, -0.26kg, and 0.30kg for IMF, SSF, and LW respectively. Results for selection response using indices C-G can be found in Table 1. In the absence of direct selection due to high costs of phenotyping, respectable selection response can be achieved by indirect selection using traits with lower cost of collection.

Determining the appropriate selection index for Rayeni Cashmere goat under pasture-based production system

2018 ◽  
Vol 58 (9) ◽  
pp. 1595
Author(s):  
Najmeh Kargar Borzi ◽  
Ahmad Ayatollahi Mehrgardi ◽  
Masood Asadi Fozi ◽  
Mahmood Vatankhah
Keyword(s):  
Production System ◽  
Selection Criteria ◽  
Selection Index ◽  
Economic Value ◽  
Herd Size ◽  
Cashmere Goat ◽  
Economic Values ◽  
Economic Weights ◽  
Selection Indices ◽  
Beneficial Traits

The aim of the present study was to identify the significance of Rayeni Cashmere goat’s socioeconomic traits so as to derive economic weights for the selection criteria that can be used easily by goat breeders. A deterministic bio-economic model was used to estimate economic value for adult bodyweight of doe (BWD), annual milk yield (MW), annual cashmere weight (CW), bodyweight of kids sold at 6.5 months (WK), and number of kids sold at 6.5 months per doe (NK). The relative importance of traits was determined on the basis of the estimated economic values, and, consequently, the most beneficial traits were applied to construct selection indices. Five selection indices with different herd sizes and buck ratios were proposed (I1–I5). The traits included in each index were as follows: BWD, MW, CW, WK and NK (I1); MW, CW, WK and NK (I2); BWD, MW, WK and NK (I3); BWD, MW and CW (I4); and BWD, CW, WK and NK (I5). Absolute economic values (US$) of BWD, MW, CW, WK and NK traits were $–0.870, $0.111, $5.660, $21.655 and $1.712 respectively. The results indicated that in all indices, the genetic and economic gains were elevated by an increased herd size and a decreased buck ratio. The maximum values of genetic and economic gains were obtained in herd size of 400 and buck ratio of 0.04. The highest genetic gain was obtained under Index 1, while the highest amount of economic gain was acquired under Index 2; however, the maximum accuracy of selection index was achieved under Index 1. The obtained results revealed that the most appropriate selection index for this breed is Index 1, which includes BWD, MW, CW, WK and NK. By applying Index 1, we could concurrently promote improvement of all traits, which highlights the potential of this index as a good promising strategy for developing selection criteria of Rayeni Cashmere goat under a pasture-based production system.

scholarly journals Genetic dissimilarity, selection index and correlation estimation in a melon germplasm

2021 ◽  
Vol 39 (1) ◽  
pp. 46-51
Author(s):  
Danilo A Gomes ◽  
Igor M Alves ◽  
Gabriel M Maciel ◽  
Ana Carolina S Siquieroli ◽  
Joicy Vitória M Peixoto ◽  
...  
Keyword(s):  
Cavity Length ◽  
Multivariate Analyses ◽  
Selection Index ◽  
Genetic Material ◽  
Soluble Solids ◽  
Breeding Programs ◽  
Correlation Estimation ◽  
Selection Indices ◽  
Genetic Dissimilarity ◽  
Selection For

ABSTRACT The success of breeding programs depends on genetic variability. Individuals selected based on a few traits may be a limitation. One alternative is the use of nonparametric indices. However, there is no information on the use of selection indices in melon germplasms. The present study aimed to estimate genetic dissimilarity in a melon germplasm and select potential parent plants for future breeding programs. The genetic material consisted of 37 melon accessions. The traits assessed were fruit diameter and length, diameter and length of the fruit cavity and total soluble solids. Genetic dissimilarity was assessed by multivariate analyses (UPGMA and Tocher). Selection gain estimates were analyzed by comparing the classic Smith-Hazel and sum of ranks indices. Genetic diversity was observed between accessions. The variable that contributed most to genetic dissimilarity was fruit cavity length. Simultaneous selection for the traits assessed based on the sum of ranks index is better suited to melon germplasm assessment. The best accessions for the five variables simultaneously were UFU07, UFU23, UFU09, UFU21, UFU28 and UFU30.

scholarly journals Genetic Merit Based Genotype Selection for Physical Fruit Traits in Mango

2014 ◽  
Vol 2 (6) ◽  
pp. 260
Author(s):  
Arun Kumar Barholia ◽  
Sangeeta Yadav
Keyword(s):  
Mangifera Indica ◽  
Selection Index ◽  
Fruit Yield ◽  
Fruit Traits ◽  
Genetic Merit ◽  
Selection Indices ◽  
Improvement Programme ◽  
Selection For ◽  
Fruit Characters

Selection indices based on their genetic merit of fruit characters were constructed for fruit yield/tree in 48 genotypes in mango (Mangifera indica L.). Genotypes, SBM 01-35, SBM 01-26, SBM 01-9, SBM 01- 10 and SBM 01-26 in on year while, SBM 01-12, SBM 01-36, SBM 01-26, SBM 01-28 and SBM 01- 9 in off year recorded highest fruit yield /tree. Genotypes SBM 01-10, SBM 01-36, SBM 01-09, SBM 01-30 and SBM 01-6 exhibited comparatively high estimates of selection indices during on year while, SBM 01-36 followed by SBM 01-12, Totapari, SBM 01-17 and SBM 01-29 showed the maximum estimates of selection index for fruit yield/ tree during off year. Alphonso followed by SBM 01-5, SBM 01-13, Langra and SBM 01-14 during on year and Dashehari, Safeda, SBM 01-3 and SBM 01-39 in off year exhibited the minimum estimates of varietal indices. Genotypes differed considerably in their ranking pattern based on selection indices. Genotypes SBM 01-9, SBM 01-10, SBM 01-30, SBM 01-6 and SBM 01-36 showed maximum varietal indices and phenotypic performance in both the years thus, appeared promising for use as parent in mango improvement programme.

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.

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.

scholarly journals Yield traits as selection indices in seedling populations of cassava

2010 ◽  
Vol 10 (3) ◽  
pp. 191-196 ◽  
Author(s):  
Henry Fred Ojulong ◽  
Maryke Tine Labuschagne ◽  
Liezel Herselman ◽  
Martin Fregene
Keyword(s):  
Dry Matter ◽  
Tuber Yield ◽  
Selection Index ◽  
Matter Content ◽  
Root Weight ◽  
Dry Matter Content ◽  
Root Yield ◽  
Breeding Scheme ◽  
Selection Indices ◽  
Root Quality

The cassava breeding scheme currently used is long, because initial stages concentrate mainly on improving yield, with root quality selection following later. To shorten the scheme, yield and root quality should be selected simultaneously, starting at the seedling nursery. In this study, a nursery comprising of eight cassava families and 1885 seedlings developed from parents adapted to three major agro-ecologies, were evaluated for yield related traits in Colombia. Percentage dry matter content (DMC) and harvest index produced similar ranking of the parents. Tuber yield, weight, and number showed potential of increasing yield through conventional breeding. A selection index including fresh root yield, percentage DMC, root weight and roots per plant, with heavier weights being assigned to root weight and roots per plant, should be used.

Selection for improved carcass composition in Suffolk Sheep : Interim Results

1990 ◽  
Vol 1990 ◽  
pp. 9-9
Author(s):  
G Simm ◽  
W S Dingwall ◽  
S V Murphy ◽  
J FitzSimons ◽  
W R Brown
Keyword(s):  
Cost Effective ◽  
Carcass Composition ◽  
Short Term ◽  
Genetic Potential ◽  
Selection Indices ◽  
Selection For ◽  
Breed Selection ◽  
Terminal Sire ◽  
Suffolk Sheep

It is likely that returns from lamb production in future will depend, much more than at present, on producing leaner carcasses. There are several short-term changes in management which could produce leaner carcasses. However, In the longer term genetic Improvement, particularly by within-breed selection In terminal sire breeds, is likely to provide permanent, cumulative and cost-effective benefits In carcass composition. In the early 1980s a research project was started at the Edinburgh School of Agriculture, using Suffolk sheep, to examine the genetic potential for Improving carcass composition In terminal sires. The work commenced with an evaluation of techniques for in vivo measurement of carcass composition (Simm, 1987) and derivation of selection indices to incorporate In vivo measurements (Simm and Dingwall, 1989). Since 1985 In vivo measurement and Index selection have been practised In the experimental flock, which now numbers about 220 ewes. This paper reports the interim results of selection.

Physiological responses to selection for carcass lean content in a terminal sire breed of sheep

1991 ◽  
Vol 1991 ◽  
pp. 25-25
Author(s):  
N.D. Cameron
Keyword(s):  
Lipid Metabolism ◽  
Genetic Improvement ◽  
Selection Index ◽  
Carcass Composition ◽  
Physiological Traits ◽  
Esterified Fatty Acids ◽  
Breeding Programmes ◽  
Selection For ◽  
Terminal Sire ◽  
Sire Breed

Sheep breeding programmes for genetic improvement in carcass composition of terminal sires measure livewelght and ultrasonic backfat and muscle depths for inclusion in a selection index to predict genetic merit. Physiological traits which were genetically correlated with carcass traits could be incorporated into the selection index to increase the accuracy of selection and the rate of genetic improvement.This study examined differences in physiological traits between lines selected for high or low carcass lean content. The measured physiological traits were chosen according to their role in protein and lipid metabolism : b-hydroxybutyrate (BHB) and glucose (GLUC) : indicators of energy balance; triglyceride (TRIG) and non-esterified fatty acids (NEFA) : intermediaries of lipid metabolism; UREA and creatinine (CREA) : indicators of nitrogen / amino acid metabolism and insulin-like growth factor-1 (IGF-1): an Indicator of growth hormone status.

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