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EUCLIDES FILHO, K.. |
O instrumento mais simples que o melhorista tem, a sua disposição, para melhoria da produção de gado de corte e a seleção individual. Seleção nada mais e que o processo de escolha de indivíduos que serão pais na próxima geração. Esta escolha pode ser efetuada selecionando-se aqueles indivíduos superiores para a característica de interesse dentro do próprio rebanho, ou ainda, entre indivíduos provenientes de rebanhos diferentes. No primeiro caso, atenção especial deve ser dada no sentido de se evitar os problemas que surgem como resultado do aumento da consanguinidade. O sucesso desta seleção esta na dependência da qualidade e variabilidade genética, permitir, em muitos casos, a utilização de reprodutores melhores do que aqueles produzidos na própria... |
Tipo: Documentos (INFOTECA-E) |
Palavras-chave: Bovino de corte; Programa; Melhoramento genético; Selection; Program.; Seleção.; Breeding.; Beef cattle. |
Ano: 1985 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/318187 |
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Vandeputte, Marc; Fraslin, Clemence; Haffray, Pierrick; Bestin, Anastasia; Allal, Francois; Kocour, Martin; Prchal, Martin; Dupont-nivet, Mathilde. |
Fillet yield (i.e. the proportion of edible muscle in a fish) is a key economic trait for species sold as fillets. Its genetic improvement is complicated by several of its characteristics 1) it is a ratio trait, 2) its numerator (fillet weight) and denominator (body weight) are strongly correlated (correlations in the range 0.89-0.99), 3) it offers little phenotypic variation and 4) it cannot be measured on alive breeding candidates. In a former study, we showed that it could be improved by selection, especially with three selection indices, fillet yield, residual fillet weight and a ratio-specific linear index. However, it is well known that the heritability of ratio traits does not permit a reliable prediction of genetic gains. As predictability of... |
Tipo: Text |
Palavras-chave: Aquaculture; Genetics; Heritability; Selection; Linear index; Residual fillet weight; Selection response; Simulation; Processing yields. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00612/72378/71390.pdf |
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Jacquot, Maude; Rao, Pavuluri P.; Yadav, Sarita; Nomikou, Kyriaki; Maan, Sushila; Jyothi, Y. Krishna; Reddy, Narasimha; Putty, Kalyani; Hemadri, Divakar; Singh, Karam P.; Maan, Narender Singh; Hegde, Nagendra R.; Mertens, Peter; Biek, Roman. |
For segmented viruses, rapid genomic and phenotypic changes can occur through the process of reassortment, whereby co-infecting strains exchange entire segments creating novel progeny virus genotypes. However, for many viruses with segmented genomes, this process and its effect on transmission dynamics remain poorly understood. Here, we assessed the consequences of reassortment for selection on viral diversity through time using bluetongue virus (BTV), a segmented arbovirus that is the causative agent of a major disease of ruminants. We analysed ninety-two BTV genomes isolated across four decades from India, where BTV diversity, and thus opportunities for reassortment, are among the highest in the world. Our results point to frequent reassortment and... |
Tipo: Text |
Palavras-chave: Bluetongue virus; Evolution; Reassortment; India; Selection. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00667/77882/80042.pdf |
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Huvet, Arnaud; Degremont, Lionel; Labreuche, Yannick; Daniel, Jean-yves; Dubrunfaut, Thomas; Boudry, Pierre; Haure, Joel; Bedier, Edouard; Ropert, Michel; Herpin, Amaury; Cunningham, Charles; Moal, Jeanne; Samain, Jean-francois. |
Summer mortality associated with juveniles of the oyster Crassostrea gigas is the result of a complex interaction between the host, pathogens and environment. Divergent selection based on summer survival have been applied to produce families with resistant and susceptible progeny. Here, we describe the use of suppression subtractive hybridization to generate 150 clones that were differentially regulated between resistant and susceptible F2 progeny. The nucleotide sequence of these 150 clones was determined. Among the 25 unique sequences that matched with the products of known genes, those putatively implicated in energy generation (12%) and immune function (16%), systems suspected to be implicated in summer mortality, were extended and analyzed by real... |
Tipo: Text |
Palavras-chave: Selection; Gene; Genetic; Summer mortality; Crassostrea gigas; Pacific oysters. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/acte-3447.pdf |
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Lapegue, Sylvie; Renault, Tristan. |
The most known and certainly the most important contribution of genetics to the oyster indus try is the development of the triploid cupped oyster. Released for the first time in the 1980s, the triploid oyster has triplets of chromosomes instead of pairs. Currently, triploid oysters are obtained by crossing diploid and tetraploid oysters. These oysters are characterized by a near lack of milt in summer, which makes them generally popular with consumers, and by a faster growth, allowing a shorter production cycle. In parallel, the exploitation of natural resistance in the diversity of French oysters has been considered to improve the health of farmed populations which is a major challenge for the sustainability of aquaculture farms. Currently, the... |
Tipo: Text |
Palavras-chave: Huître creuse; Triploïdie; Sélection; Maladies; Ostréiculture; Cupped oyster; Triploidy; Selection; Disease; Shellfish farming. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00498/60931/64326.pdf |
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Vandeputte, Marc. |
Common carp was the first domesticated fish species and is now a major species in worldwide aquaculture. Although research has generated a considerable body of knowledge about its genetics, genetic improvement programmes are virtually non-existent in this species and only crossbreeding is used in practice. The main reasons are the inefficiency of methods usually effective in other aquaculture species (monosexing, triploidy), and the bad image of selective breeding which is difficult to implement in ponds, and for which reliable genetic parameters were missing until recently. These parameters are now becoming available through the use of parentage assignment with microsatellite markers. However, the question of selective breeding for growth remains far from... |
Tipo: Text |
Palavras-chave: Selection; Population genetics; Cyprinus carpio; Breeding; Aquaculture. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6563.pdf |
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Guinand, B; Rolland, Jean-luc; Bonhomme, Francois. |
Coastal and estuarine areas in the Bay of Biscay are essential nursery habitats for sole (Solea solea). Using three intronic markers, we investigated patterns of genetic differentiation among cohorts of juveniles (0+, 1+, sub-adults) inhabiting four major nurseries in the Vilaine and Loire river estuaries, the Pertuis d' Antioche strait, and the Gironde estuary. Genetic differentiation was not significant for the age 0- and 1-groups, but was among sub-adult samples (theta(WC) = 0.017; P = 0.031). Hierarchical analyses of genotypic frequencies by nested multivariate ANOVA using redundancy analysis indicated that northern nurseries of Loire and Vilaine rivers had different patterns of genotypic variation with age than southern nurseries of the Pertuis d'... |
Tipo: Text |
Palavras-chave: Selection; Genetic drift; EPIC PCR; Population genetics; Coastal nurseries; Juveniles; Flatfish. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4299.pdf |
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Azema, Patrick; Travers, Marie-agnes; Benabdelmouna, Abdellah; Degremont, Lionel. |
French production of the Pacific cupped oyster, Crassostrea gigas, is currently threatened by two pathogens, OsHV-1 and V. aestuarianus. While oysters selected for their higher resistance to OsHV-1 are now available for the industry, the impact of V. aestuarianus on such oysters is unknown, especially for triploids. In addition, experimental infection has used the virus or the bacteria alone, but there have been no investigations of dual exposure to these pathogens. This study is the first report of single or dual exposure in spat (Spat1 and Spat2), juvenile and adult naïve oysters. For each of the two stocks evaluated, unselected oysters and oysters selected for their higher resistance to OsHV-1 infection were tested, as well as their triploid siblings of... |
Tipo: Text |
Palavras-chave: Vibrio aestuarianus; OsHV-1; Dual exposure; Ploidy; Selection; Crassostrea gigas. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00347/45835/45918.pdf |
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Registros recuperados: 204 | |
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