Genetic parameters and selection indexes in F2 and F2:3 Soybean populations

2021 ◽  
Author(s):  
Carolina Oliveira Silva ◽  
Osvaldo Hamawaki ◽  
Ana Paula Oliveira Nogueira ◽  
Myckell Ramos Campos Almeida ◽  
Douglas Goulart Castro ◽  
...  
Keyword(s):  
Genetic Parameters ◽  
Selection Indexes

scholarly journals Estimation of Genetic Parameters for Pork Quality, Novel Carcass, Primal-Cut and Growth Traits in Duroc Pigs

Animals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 779 ◽  
Author(s):  
Hannah E. Willson ◽  
Hinayah Rojas de Oliveira ◽  
Allan P. Schinckel ◽  
Daniela Grossi ◽  
Luiz F. Brito
Keyword(s):  
Genetic Parameters ◽  
Growth Traits ◽  
Low Cost ◽  
Selection Index ◽  
Carcass Traits ◽  
Genetic Correlations ◽  
Pork Quality ◽  
Production Traits ◽  
Genetic Progress ◽  
Selection Indexes

More recently, swine breeding programs have aimed to include pork quality and novel carcass (e.g., specific primal cuts such as the Boston butt or belly that are not commonly used in selection indexes) and belly traits together with growth, feed efficiency and carcass leanness in the selection indexes of terminal-sire lines, in order to efficiently produce pork with improved quality at a low cost to consumers. In this context, the success of genetic selection for such traits relies on accurate estimates of heritabilities and genetic correlations between traits. The objective of this study was to estimate genetic parameters for 39 traits in Duroc pigs (three growth, eight conventional carcass (commonly measured production traits; e.g., backfat depth), 10 pork quality and 18 novel carcass traits). Phenotypic measurements were collected on 2583 purebred Duroc gilts, and the variance components were estimated using both univariate and bivariate models and REML procedures. Moderate to high heritability estimates were found for most traits, while genetic correlations tended to be low to moderate overall. Moderate to high genetic correlations were found between growth, primal-cuts and novel carcass traits, while low to moderate correlations were found between pork quality and growth and carcass traits. Some genetic antagonisms were observed, but they are of low to moderate magnitude. This indicates that genetic progress can be achieved for all traits when using an adequate selection index.

Predicted lamb carcase component changes from using different selection indexes and endpoints

1995 ◽  
Vol 1995 ◽  
pp. 44-44
Author(s):  
G.E. Pollott
Keyword(s):  
Genetic Parameters ◽  
Genetic Progress ◽  
Fat Depots ◽  
Selection Indexes ◽  
Lean Weight

Recent estimates of the genetic parameters of the traits used in the MLC Lean Index (Simm and Dingwall, 1989) have suggested that the rate of genetic progress in carcase quality could be improved by using alternative indexes (Pollott, 1994). This study was carried out to investigate the changes in a range of carcase components using these alternative selection indexes. Interest is particularly focused on changes in fat depots and bone weight under selection, as well as that of the primary trait of interest, lean weight.

scholarly journals Genetic parameters and selection of soybean lines based on selection indexes

2017 ◽  
Vol 16 (3) ◽  
Author(s):  
F.G. Teixeira ◽  
O.T. Hamawaki ◽  
A.P.O. Nogueira ◽  
R.L. Hamawaki ◽  
G.L. Jorge ◽  
...  
Keyword(s):  
Genetic Parameters ◽  
Selection Indexes ◽  
Selection Of

scholarly journals Genetic parameters and selection indexes for biofortified red leaf lettuce

2021 ◽  
Vol 56 ◽  
Author(s):  
Joicy Vitória Miranda Peixoto ◽  
Gabriel Mascarenhas Maciel ◽  
Rafael Resende Finzi ◽  
Lucas Medeiros Pereira ◽  
Ana Carolina Silva Siquieroli ◽  
...  
Keyword(s):  
Genetic Parameters ◽  
Block Design ◽  
Carotenoid Content ◽  
Anthocyanin Content ◽  
Plant Analysis ◽  
High Magnitude ◽  
Selection Indices ◽  
Randomized Complete Block Design ◽  
Selection Indexes ◽  
Leaf Lettuce

Abstract: The objective of this work was to determine the genetic parameters and the efficiency of different selection indices for biofortified red leaf lettuce (Lactuca sativa var. crispa) lines with agronomic and nutritional potential. The experiment was carried out in a randomized complete block design with three replicates and 31 crisp-textured and red-tinted leaf lettuce genotypes: the Belíssima cultivar, with a low carotenoid content and rich in anthocyanins; and 30 lines from the cross between the Belíssima and Uberlândia 10000 cultivars, rich in carotenoids and with a low anthocyanin content. The assessed traits were: total green mass (g), stem diameter (cm), leaf count, plant diameter (cm), foliar temperature (°C), soil plant analysis development (SPAD) index, anthocyanin content (mg 100 g-1 sample), and bolting (days after sowing). To estimate selection gains, 12 genotypes were selected through selection indices. The traditional index proposed by Smith & Hazel and the sum of ranks index by Mulamba & Mock provided the highest selection gains in the biofortified lettuce. The coefficient of genotypic determination for leaf count, anthocyanin content, bolting, and SPAD index is of high magnitude.

scholarly journals Genetic parameters and line selection of Cucurbita pepo based on selection indices

2020 ◽  
Vol 36 ◽  
Author(s):  
Igor Forigo Beloti ◽  
Gabriel Mascarenhas Maciel ◽  
Fernando Cezar Juliatti ◽  
Rafael Resende Finzi ◽  
Daniel Bonifácio Oliveira Cardoso
Keyword(s):  
Leaf Area Index ◽  
Leaf Area ◽  
Genetic Parameters ◽  
Leaf Temperature ◽  
Area Index ◽  
Balanced Distribution ◽  
Multiple Characteristics ◽  
Simultaneous Selection ◽  
Selection Indexes ◽  
Selection Of

In the improvement of pumpkins, the selection based on one or a few characters of interest tends to be less efficient, leading to a superior product only compared to the few characters selected. To maximize the simultaneous selection of multiple characteristics of interest, selection indexes are used to obtain a numerical value resulting from the combination of the characters on which the simultaneous selection is to be practiced. The objective of this study was to determine genetic parameters and the most appropriate selection indexes in strains of Summer squash (C. pepo). Statistical analyzes were performed based on 65 genotypes belonging to the vegetable germplasm bank of the Federal University of Uberlândia. The variables analyzed were: leaf area index, precocity, SPAD index, productivity. plant-1, number of fruits. Plant-1, leaf temperature, NDVI index and NDRE index. The indexes were used: Smith (1936) and Hazel (1943), the sum of “Ranks” by Mulamba and Mock (1978), and Willians (1962). The selection methodologies selected ten individuals (15% of the genotypes). The values found for h² (%) ranged from 36.92% (SPAD) to 59.65% (cycle). The values obtained in the CVg / CVe quotient were below 1, varying from 0.18 for leaf temperature to 0.70 for the cycle, with the other variables close to 0.5. The CVg genetic variation coefficient (%) was also low, ranging from 1.84% for leaf temperature to 30.94% for productivity. The greatest gains obtained with direct and indirect selection were for the characters productivity (35.92%), NDRE (33.04%), number of fruits (28.93%) and leaf area index (22.72%). The Mulamba and Mock (1978) index showed the highest total selection gain value, providing a balanced distribution of selection gains, choosing the genotypes: 8, 31, 34, 38, 42, 64, 65, 66, 67 and 68.

scholarly journals PSVIII-37 Estimation of genetic parameters for novel meat quality and carcass traits in Duroc pigs

2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 265-265
Author(s):  
Hannah E Willson ◽  
Hinayah Oliveira ◽  
Allan Schinckel ◽  
Daniela Grossi
Keyword(s):  
Meat Quality ◽  
Genetic Parameters ◽  
Carcass Traits ◽  
Genetic Selection ◽  
Relationship Matrix ◽  
Breeding Programs ◽  
Genetically Improved ◽  
Selection Indexes ◽  
Selection For ◽  
Terminal Sire

Abstract In recent years, swine breeding programs have turned their selection attentions from focusing mostly on growth, feed efficiency and percent fat towards including meat quality and carcass traits with aims to efficiently produce nutritious and tasty meat to attend a growing demand for pork. In this context, the success of genetic selection for such traits relies on several factors, especially the heritability (h2) of the traits included in the selection indexes. Therefore, this study aimed to estimate genetic parameters for seven meat quality and carcass traits in Duroc pigs, including: meat lightness (L*), loin pH (pH), marbling (MARB), untrimmed belly weight (UBLW), untrimmed ham weight (UHW), untrimmed loin weight (ULW), and untrimmed shoulder weight (USW). Phenotypic measurements were collected on 2,857 purebred Duroc gilts from a Terminal Sire line. The pedigree-based relationship matrix included 5,316 animals and genetic parameters were estimated using univariate models under the REML approach. The traits studied here were shown to be moderately to highly heritable (h2 estimates were 0.32, 0.42, 0.47, 0.35, 0.24, 0.28, and 0.28 for L*, pH, MARB, UBLW, UHW, ULW, and USW, respectively). Our findings suggest that these traits are under genetic control, and thus, they can be genetically improved if included in selection schemes. The next step will be to estimate the genetic correlation between those traits (among themselves and with other traits), as well as alternatives to efficiently incorporate these traits in the selection indexes.

scholarly journals   Estimation of genetic parameters of reproductive traits in Zandi sheep using linear and threshold models

2012 ◽  
Vol 57 (No. 8) ◽  
pp. 382-388 ◽  
Author(s):  
H. Mohammadi ◽  
M. Moradi Shahrbabk ◽  
M. Vatankhah
Keyword(s):  
Environmental Effects ◽  
Fixed Effects ◽  
Strong Influence ◽  
Genetic Parameters ◽  
Reproductive Traits ◽  
Linear Analysis ◽  
Threshold Analysis ◽  
Selection Indexes ◽  
Estimation Of Genetic Parameters ◽  
Zandi Sheep

Genetic parameters for reproductive traits in Zandi sheep were estimated from data records of 5025 lambs from 178 sires and 1967 dams collected between the years 1993 and 2010 using ASReml statistical package. Genetic parameters were estimated for four basic and two composite traits. Year of lambing and age of ewe were used as fixed effects. Due to repeated record of ewe animal direct genetic effects and permanent environmental effects were considered random. The heritability estimates for conception rate, number of lambs born, number of lambs born alive, number of lambs alive at weaning, number of lambs born per ewe exposed, and number of lambs weaned per ewe exposed were low with linear model – 0.05, 0.14, 0.12, 0.09, 0.05, and 0.04 respectively while the estimates resulting from threshold analysis were 0.11, 0.19, 0.14, 0.16, 0.12, and 0.11, respectively. Estimates of heritabilities for animal genetic and permanent environmental effects were low mainly due to the typical strong influence of environmental factors on reproductive traits. Estimates of repeatabilities for animal permanent environmental effects were low to medium by linear analysis, and medium by threshold analysis. These estimates of genetic parameters may provide a basis for deriving selection indexes for reproductive traits.  

scholarly journals  Reduction of traits for genetic evaluation of linear described traits in the Old Kladruber horse

2012 ◽  
Vol 57 (No. 4) ◽  
pp. 160-170 ◽  
Author(s):  
L. Vostrý ◽  
J. Přibyl ◽  
P. Šimeček
Keyword(s):  
Genetic Similarity ◽  
Genetic Parameters ◽  
Selection Index ◽  
Genetic Parameter ◽  
Genetic Correlations ◽  
Principal Component ◽  
Parameter Estimates ◽  
Selection Indexes ◽  
Measure Of Uncertainty ◽  
Selection Of

The estimated genetic parameters were used for selection of important conformation traits and reduction in the number of the described characteristics. For reduction in the number of described traits from the original 36 to 24, the traits were selected according to: measure of genetic similarity (cluster analysis), measure of uncertainty multidimensional quantity, value of the variance of aggregate genotype, value of the variance of selection index and correlation of trait to the first principal component of the genetic matrix. Reduction in the number of the described traits was based on the value of heritability coefficient and genetic correlations matrix. The reliabilities of selection indexes were estimated between 0.41 and 0.53. Among the three multivariate analysis methods evaluated in this study, the variance of selection index had the highest reliabilities of selection indexes. The estimation of selection index variance which omitted traits with low heritability coefficient and high genetic correlation was the most suitable for the traits selection. This procedure would enable the breeders to reduce field costs (e.g. time, labour) required for obtaining the genetic parameter estimates necessary for a specific breeding programme.  

scholarly journals Possibilities of developing Favourable Body Fat Partition Via Selection Indexes – Application on Rabbits

2000 ◽  
Vol 43 (2) ◽  
pp. 193-202
Author(s):  
A. R. Schemeis ◽  
O. Y. Abdallah
Keyword(s):  
Body Weight ◽  
Body Fat ◽  
Genetic Parameters ◽  
Breeding Value ◽  
True Breeding ◽  
Total Body Fat ◽  
Unit Increase ◽  
Selection Indexes ◽  
Total Fat ◽  
Total Body

Abstract. Estimates of phenotypic and genetic parameters of body fat partition and other related traits were calculated using an experimental material of 152 New Zealand White rabbits of 15 bucks and 42 adult does. To construet nine selection indexes aiming at improving fat partition, estimates of phenotypic and genetic parameters for weight and linear dimensions of the live body were also obtained. The aggregate genotype included the percentage total body fat depositing subcutaneously and intermuscularly at the marketing age of 12 weeks. The füll index included the weaning body weight, marketing body weight, body length, loin width and heart girth. The full index had the highest correlation with the true breeding value (rT| = 0.597). Comparable accuracy (rTi = 0.561) would be expected from the best-reduced index (I7 = 0.009 BW –0.988 HG) combining marketing body weight and heart girth. At each round of selection with intensity =1, such a reduced index is expected to result in developing rabbits with advantageous fat partition in terms of higher percentage total body fat depositing subcutaneously (+0.35 unit %), intermuscularly (+1.91 unit %) and intramuscularly (as reflected by 0.15 unit % increase in carcass muscle yield. As compared with its unrestricted form, the best reduced index reduced to zero change in total body fat (I7(TBF)) would result in drastic decline in percentage total fat depositing as kidney knob and Channel fat (+0.32 vs. –0.18 unit %) with little amelioration in percentage total fat aecumulating in the other depots. Selection on I7(TBF) instead of 17 would reduce improvement in marketing body weight (+0.52 vs. +0.33 gm), carcass yield (+0.10 vs. 0.04 unit %) and carcass boneless meat yield (+0.19 vs. 0.07 unit %) with increase of gain in carcass muscle yield (+0.15 vs. 0.32 unit %).

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