Consulta: subjectFacets:"Genetic correlations"
Registros recuperados: 18
Data/hora: 29/05/2024 02:23:54

Genetic parameters for five traits in Africanized honeybees using Bayesian inference
Provedor de dados: 74
Autores: Padilha,Alessandro Haiduck; Sattler,Aroni; Cobuci,Jaime Araújo; McManus,Concepta Margaret.
Heritability and genetic correlations for honey (HP) and propolis production (PP), hygienic behavior (HB), syrupcollection rate (SCR) and percentage of mites on adult bees (PMAB) of a population of Africanized honeybees were estimated. Data from 110 queen bees over three generations were evaluated. Single and multi-trait models were analyzed by Bayesian Inference using MTGSAM. The localization of the hive was significant for SCR and HB and highly significant for PP. Season-year was highly significant only for SCR. The number of frames with bees was significant for HP and PP, including SCR. The heritability estimates were 0.16 for HP, 0.23 for SCR, 0.52 for HB, 0.66 for PP, and 0.13 for PMAB. The genetic correlations were positive among productive traits...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Heritability; Genetic correlations; Environmental effects; Apis mellifera.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572013000200011

Responses to reciprocal recurrent selection and changes in genetic variability in IG-1 and IG-2 maize populations
Provedor de dados: 74
Autores: Santos,Mateus Figueiredo; Moro,Gustavo Vitti; Aguiar,Aurélio Mendes; Souza Jr.,Cláudio Lopes de.
This paper reports the effects of three cycles of reciprocal recurrent selection (RRS) on the means, genetic variances, and on the genetic correlations for several traits in the IG-1 and IG-2 maize (Zea mays L.) populations. Interpopulation full-sib progenies from cycle zero (C0) and from cycle 3 (C3) of RRS were evaluated in two locations. RRS was highly effective to improve the traits according the objectives of the program: grain yield and prolificacy increased significantly, while plant height, ear height, and ear placement decreased significantly. Genetic variances for all traits decreased significantly from C0 to C3, but the genetic correlations did not change consistently across the cycles of selection. The expected responses to the fourth cycle of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Maize; Responses to selection; Genetic variances; Genetic correlations.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572005000500021

Effect of lactation length adjustment procedures on genetic parameter estimates for buffalo milk yield
Provedor de dados: 74
Autores: Baldi,Fernando; Laureano,Monyka Marianna Massolini; Gordo,Daniel Gustavo Mansan; Bignardi,Annaiza Braga; Borquis,Rusbel Raul Aspilcueta; Albuquerque,Lucia Galvão de; Tonhati,Humberto.
The objectives of this study were to estimate the genetic parameters for milk yield unadjusted and adjusted for days in milk and, subsequently, to assess the influence of adjusting for days in milk on sire rank. Complete lactations from 90 or 150 days of lactation to 270 or 350 days in milk were considered in these analyses. Milk yield was adjusted for days in milk by multiplicative correction factors, or by including lactation length as a covariable in the model. Milk yields adjusted by different procedures were considered as different traits. Heritability estimates varied from 0.17 to 0.28. Genetic correlation estimates between milk yields unadjusted and adjusted for days in milk were greater than 0.82. Adjusting for days in milk affected the parameter...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Genetic correlations; Heritability; Lactation length; Milk production; Rank correlations.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000100012

Genetic parameters for faecal egg count, packed-cell volume and body-weight in Santa Inês lambs
Provedor de dados: 74
Autores: Lôbo,Raimundo N.B.; Vieira,Luiz S.; Oliveira,Amaury A. de; Muniz,Evandro N.; Silva,José M. da.
Worm infection is one of the main factors responsible for economic losses in sheep breeding in Brazil. Random regression analysis was used to estimate genetic parameters for the factors faecal egg-count (FEC), packed-cell volume (PCV) and body weight (BW) in Santa Inês lambs. Data from 119 female, offspring of nine rams, were collected between December, 2005 and December, 2006, from the experimental flock of Embrapa Tabuleiros Costeiros, the Brazilian Agricultural Research Corporation located in Frei Paulo, SE, Brazil. After weaning, females were drenched until the faecal egg count had dropped to zero. Two natural challenges were undertaken. FEC heritability was extremely variable, this increasing from 0.04 to 0.27 in the first challenge and from 0.01 to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Genetic correlations; Heritability; Legendre polynomials; Random regression.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572009000200014

Test-day milk yield as a selection criterion for dairy buffaloes (Bubalus bubalis Artiodactyla, Bovidae)
Provedor de dados: 74
Autores: Tonhati,Humberto; Cerón-Muñoz,Mário Fernando; Oliveira,João Ademir de; El Faro,Lenira; Lima,André Luís Ferreira; Albuquerque,Lucia Galvão de.
Due to the great demand for buffalo milk by-products the interest in technical-scientific information about this species is increasing. Our objective was to propose selection criteria for milk yield in buffaloes based on total milk yield, 305-day milk yield (M305), and test-day milk yield. A total of 3,888 lactations from 1,630 Murrah (Bubalus bubalis) cows recorded between 1987 and 2001, from 10 herds in the State of São Paulo, Brazil, were analyzed. Covariance components were obtained using the restricted maximum likelihood method applied to a bivariate animal model. Additive genetic and permanent environmental effects were considered as random, and contemporary group and lactation order as fixed effects. The heritability estimates were 0.22 for total...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Genetic correlations; Genetic parameters; Heritability; Selection efficiency.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572008000400012

Genetic parameters for milk, fat and protein yields in Murrah buffaloes (Bubalus bubalis Artiodactyla, Bovidae)
Provedor de dados: 74
Autores: Aspilcueta-Borquis,Rusbel Raúl; Sesana,Roberta Cristina; Berrocal,Milthon Honorio Munoz; Seno,Leonardo de Oliveira; Bignardi,Annaiza Braga; El Faro,Lenira; Albuquerque,Lucia Galvão de; Camargo,Gregório Miguel Ferreira de; Tonhati,Humberto.
The objective of the present study was to estimate genetic parameters for test-day milk, fat and protein yields and 305-day-yields in Murrah buffaloes. 4,757 complete lactations of Murrah buffaloes were analyzed. Co-variance components were estimated by the restricted maximum likelihood method. The models included additive direct genetic and permanent environmental effects as random effects, and the fixed effects of contemporary group, milking number and age of the cow at calving as linear and quadratic covariables. Contemporary groups were defined by herd-year-month of test for test-day yields and by herd-year-season of calving for 305-day yields. The heritability estimates obtained by two-trait analysis ranged from 0.15 to 0.24 for milk, 0.16 to 0.23 for...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Test-day model; Accumulated productions; Heritability; Genetic correlations.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572010000100014

What is the heritable component of spinal deformities in the European sea bass (Dicentrarchus labrax)?
Provedor de dados: 5
Autores: Bardon, Agnes; Vandeputte, Marc; Dupont-nivet, Mathilde; Chavanne, Herve; Haffray, Pierrick; Vergnet, Alain; Chatain, Beatrice.
Malformations in farmed fish are a prime research topic as it has a major impact on fish welfare and on the economical value of the product. In this study, the genetic component of spine deformities was estimated in European sea bass, a major species of Mediterranean aquaculture, with the use of a posteriori reconstruction of pedigree with microsatellites. Our population exhibited a very high malformation rate (81%),probably due to intense swimming of fish during pre-growing The heritability of global spine deformities was evaluated to be 0.21 +/- 0.04 on the underlying scale (033 +/- 0.06 for lordosis, 0.13 +/- 0.04 for scoliosis). Deformities scored by an internal or external examination turned out to be genetically the same trait (genetic...
Tipo: Text
Palavras-chave: Genetic correlations; Heritability; Growth; Deformities; Dicentrarchus labrax; European sea bass.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-6768.pdf

Estimation of Genetic Parameters of Fatty Acids Composition in Flesh of Market Size Common Carp (Cyprinus carpio L.) and Their Relation to Performance Traits Revealed that Selective Breeding Can Indirectly Affect Flesh Quality
Provedor de dados: 5
Autores: Prchal, Martin; Vandeputte, Marc; Gela, David; Dolezal, Marek; Blichtova, Hana; Rodina, Marek; Flaishans, Martin; Kocour, Martin.
Fish are a rich source of omega-3 polyunsaturated fatty acids (n-3 PUFAs) and thus, they should be an integral part of human diet at least twice a week. As a result, high attention has been devoted to the improvement of fatty acids (FA) content in the flesh of farmed fish through nutrition. Conversely, there are very few data on the potential of selective breeding to improve FA composition in fish. We estimated genetic parameters of fillet fatty acid content and performance traits in market size common carp cultured under semi-intensive pond conditions. The experimental stock arose through factorial mating of 7 dams and 36 sires. All families were reared communally. Pedigree was reconstructed with microsatellite markers, and 158 individuals were dressed...
Tipo: Text
Palavras-chave: Genetic correlations; Genetic improvement; Growth; Heritability; Slaughtering traits; Supplemental feeding.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00449/56043/57558.pdf

Genetic Parameters and Genome-Wide Association Studies of Quality Traits Characterised Using Imaging Technologies in Rainbow Trout, Oncorhynchus mykiss
Provedor de dados: 5
Autores: Blay, Carole; Haffray, Pierrick; Bugeon, Jérôme; D’ambrosio, Jonathan; Dechamp, Nicolas; Collewet, Guylaine; Enez, Florian; Petit, Vincent; Cousin, Xavier; Corraze, Geneviève; Phocas, Florence; Dupont-nivet, Mathilde.
One of the top priorities of the aquaculture industry is the genetic improvement of economically important traits in fish, such as those related to processing and quality. However, the accuracy of genetic evaluations has been hindered by a lack of data on such traits from a sufficiently large population of animals. The objectives of this study were thus threefold: (i) to estimate genetic parameters of growth-, yield-, and quality-related traits in rainbow trout (Oncorhynchus mykiss) using three different phenotyping technologies [invasive and non-invasive: microwave-based, digital image analysis, and magnetic resonance imaging (MRI)], (ii) to detect quantitative trait loci (QTLs) associated with these traits, and (iii) to identify candidate genes present...
Tipo: Text
Palavras-chave: Aquaculture; Fat content; Flesh colour; Magnetic resonance imaging; Fatmeter; Computer vision; Genetic correlations; QTL.
Ano: 2021
URL: https://archimer.ifremer.fr/doc/00682/79410/81958.pdf

Potential for Genetic Improvement of the Main Slaughter Yields in Common Carp With in vivo Morphological Predictors
Provedor de dados: 5
Autores: Prchal, Martin; Bugeon, Jerome; Vandeputte, Marc; Kause, Antti; Vergnet, Alain; Zhao, Jinfeng; Gela, David; Genestout, Lucie; Bestin, Anastasia; Haffray, Pierrick; Kocour, Martin.
Common carp is a major aquaculture species worldwide, commonly sold alive but also as processed headless carcass or filets. However, recording of processing yields is impossible on live breeding candidates, and alternatives for genetic improvement are either sib selection based on slaughtered fish, or indirect selection on correlated traits recorded in vivo. Morphological predictors that can be measured on live fish and that correlate with real slaughter yields hence remain a possible alternative. To quantify the power of morphological predictors for genetic improvement of yields, we estimated genetic parameters of slaughter yields and various predictors in 3-year-old common carp reared communally under semi-intensive pond conditions. The experimental...
Tipo: Text
Palavras-chave: Heritability estimates; Genetic correlations; Indirect selection; Morphological landmarks; Slaughter yields; Ultrasound imagery.
Ano: 2018
URL: http://archimer.ifremer.fr/doc/00451/56242/57806.pdf

Genetic effect of domestication selective pressures on Pacific oyster at larval stage
Provedor de dados: 5
Autores: Taris, Nicolas; Sauvage, Christopher; Ernande, Bruno; Boudry, Pierre.
Among bivalve species, the Pacific oyster, Crassostrea gigas, is the most economically important bivalve production over the world. Today, C. gigas is subject to an important production effort that leads to an intensive artificial selection. Larval stage is relatively unknown, specifically in a domestication context. Genetic consequence of artificial selection is still at a preliminary study. We aimed to tackle the consequence of inconscient domestication on the variance reproductive success focusing on larval stage, keystone of the life cycle. We studied two kinds of specific selective processes that common hatchery rearing practices exert : the effect of discarding the smallest larvae on genetic diversity and the artificial environment rearing effect via...
Tipo: Text
Palavras-chave: Selection; Genetic correlations; Genetic variability; Genetic; Domestication selective; Crassostrea gigas; Pacific oysters.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/acte-3441.pdf

Estimation of genetic parameters for test-day milk yield in Khuzestan buffalo
Provedor de dados: 86
Autores: Madad,Mostafa; Hossein-Zadeh,Navid Ghavi; Shadparvar,Abdol Ahad.
Abstract: The objective of this work was to estimate covariance functions for additive genetic and permanent environmental effects, as well as to obtain genetic parameters for buffalo test-day milk yield using random regression models on Legendre polynomials (LPs). A total of 2,538 test-day milk yield (TDMY) records from 516 first lactation records of Khuzestan buffalo, calving from 1993 to 2009 and belonging to 150 herds located in the state of Khuzestan, Iran, were analyzed. The residual variances were modeled through a step function with 1, 5, 6, 9, and 19 classes. The additive genetic and permanent environmental random effects were modeled by LPs of days in milk using quadratic to septic polynomial functions. The model with additive genetic and animal...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Covariance functions; Genetic correlations; Heritability; Legendre polynomial; Milking buffalo.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2016000700890

Genetic parameters for type traits in Holstein cows in Brazil
Provedor de dados: 96
Autores: Campos,Rafael Viegas; Cobuci,Jaime Araujo; Costa,Claudio Napolis; Braccini Neto,José.
Data from 26,558 Holstein cows in 802 herds were used to estimate genetic, residual and phenotypic parameters for 22 type traits. The model included the fixed effects of herd-year, period of classification, classifier, stage of lactation and age of cows at calving (covariate) and random genetic and residual effects. Heritability for type traits ranged from 0.10 to 0.39. The genetic variability in these traits suggested the possibility for moderate genetic gains through selection. The phenotypic correlations were moderated, mainly in the section conformation. Genetic correlations between type traits ranged from -0.44 to 0.85. High genetic correlations indicated that breeding programs could be successful without including all type traits. The selection for...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: (co)variance components; Dairy cattle; Genetic correlations; Heritability; REMLF90; Selection.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982012001000003

Genetic variability for girth growth and rubber yield in Hevea brasiliensis
Provedor de dados: 63
Autores: Gonçalves,Paulo de Souza; Silva,Marcelo de Almeida; Gouvêa,Ligia Regina Lima; Scaloppi Junior,Erivaldo José.
Basic knowledge of genetic characteristics of populations is necessary to conduct effective breeding and selection. The objective of this paper is describing the genetic variation of rubber yield and the correlation with other traits, and estimating the genetic parameters for girth growth and total number of latex vessels. Sixty seven clones of Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell.-Arg. were tested at five sites during 10 years. Characters girth growth at panel opening and rubber yield, showed broad sense heritability on plot mean level, from 0.32 to 0.66 and 0.59 to 0.92, respectively. Predicted genetic gains equal to 0.73 cm and 0.79 g increase respectively on girth and yield in the opening panel and mature phases seems realistic, even with...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Rubber tree; Heritability; Genetic correlations; Genotype-environment interaction.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162006000300006

Number of recombinations and genetic properties of a maize population undergoing recurrent selection
Provedor de dados: 63
Autores: Lima Neto,Francisco Pinheiro; Souza Júnior,Cláudio Lopes de.
In maize recurrent selection programs, selected genotypes were recombined once to generate genetic variability for the next selection cycle. Selection generates negative gametic phase disequilibrium which reduces genetic variances, and this disequilibrium is not significantly reduced with only one generation of recombination. The objective of this research was to assess the effects of one additional generation of recombination on phenotypic and genotypic parameters in a maize population undergoing recurrent selection. Selected progenies of the EPB-4 population were subjected to one and two generations of recombination, and from each generation half- and full-sib progenies were developed and evaluated at three environments for grain yield, plant and ear...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Maize improvement; Heritability coefficients; Genetic correlations.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162009000100007

Components of (co)variance of the days open in Siboney dairy cows
Provedor de dados: 45
Autores: González-Peña,D.; Espinoza-Villavicencio,J.L.; Guerra,D.; Palacios,A.; Évora,J.C.; Portales,A.
The records of 63,406 calvings of Siboney dairy cows (5/8 Holstein 3/8 Cuban Zebu) were used to estimate the components of covariance of the days open (DO). Five models were used: of repeatability; univariate; bivariate; of random regression with Legendre polynomials and the parity number as predicting variable; and a model of random regression with Legendre polynomials and heterogeneity of the residual variance. The heritability obtained with the univariate model was 0.09 in the first calving and decreased to 0.05 in the fifth. A higher estimate of heritability (0.12) was obtained with the repeatability model. When the model of random regression with heterogeneity of the residual variance was used, the heritability was higher than the values estimated...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Dairy cow; Genetic correlations; Heritability; Postpartum interval; Days open.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352010000100019

Genetic gain estimated by different selection criteria in guava progenies
Provedor de dados: 53
Autores: Paiva,Claudia Lougon; Viana,Alexandre Pio; Santos,Eileen Azevedo; Freitas,Josie Cloviane Oliveira; Amaral Junior,Antonio Teixeira do.
Abstract Guava plays an important role in Brazilian agribusiness. Among other goals, guava breeding programs aim to achieve more productive cultivars and improved fruit quality. Thus, the present study aimed to investigate genetic variability in full-sib progenies of Psidium guajava (guava) and estimate the genetic progress obtained from different selection criteria in order to select the most promising genotypes. This is the first work that uses these criteria of selection to guava. The experiment was conducted in randomized block design with 2 replicates, and 10 progenies were assessed, with 12 plants per plot. Direct and indirect selection and the classic index with 2 economic weights were used for predicting the genetic gain between and within...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Psidium guajava; Genetic correlations; Direct and indirect selection; Selection index.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052016000400418

Genetic parameters estimates and visual selection for leaves production in Ilex paraguariensis
Provedor de dados: 53
Autores: Sturion,José Alfredo; Stuepp,Carlos André; Wendling,Ivar.
ABSTRACT The selection of yerba mate superior genotypes, based on each plant leaf weight, is based on genetic parameters obtained from experimental plantations and it is practically impossible from the fourth year of age. Therefore, we estimate genetic parameters and check the feasibility of selection through notes and weight estimates of each tree at 18.5 years of age. The genetic material consists of a combined trial of provenances and progenies of half-sibs with 140 progenies from 7 provenances, installed in Ivaí, Paraná, Brazil, in a randomized block design with 10 repetitions. The genetic control of leaf production is of low magnitude (ĥ2a= 0.175042 ± 0.0393) revealing high influence of the environment. The additive genetic correlations between the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Genetic correlations; Yerba mate; Silviculture; Progeny trial.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052017000400492