RESUMO

With the rise of world fish farming, the national scenario is favorable for using native fish for intensive farming. Among the catfish, the Amazonian Jundiá (Leiarius marmoratus) is a robust candidate, easy to grow and with good organoleptic characteristics in its flesh. For productive success in captivity, it is necessary to consider some questions about the species, such as genetic variability, which must have an acceptable level in a breeding stock, in order to maintain a good diversity; this reduces losses due to inbreeding and low diversity. Therefore, the objective of this study was to characterize the genetic variability of commercial stocks of L. marmoratus from the State of Mato Grosso through microsatellite molecular markers. We analyzed 143 individuals from three stocks. The mean heterozygosity and the inbreeding coefficients observed were 0.060; 0.084; 0.141; and 0.539; 0.562; 0.514, respectively, for the stocks of Campo Verde, Juína, and Nova Mutum. The Deviation in the Hardy-Weinberg equilibrium was observed in most of the loci in the three populations. Considering the genetic differentiation, it is concluded that the three populations are very close genetically, which requires introduction of new genetic material in the stocks to enrich them genetically for a later reproductive program.(AU)

Assuntos

RESUMO

With the rise of world fish farming, the national scenario is favorable for using native fish for intensive farming. Among the catfish, the Amazonian Jundiá (Leiarius marmoratus) is a robust candidate, easy to grow and with good organoleptic characteristics in its flesh. For productive success in captivity, it is necessary to consider some questions about the species, such as genetic variability, which must have an acceptable level in a breeding stock, in order to maintain a good diversity; this reduces losses due to inbreeding and low diversity. Therefore, the objective of this study was to characterize the genetic variability of commercial stocks of L. marmoratus from the State of Mato Grosso through microsatellite molecular markers. We analyzed 143 individuals from three stocks. The mean heterozygosity and the inbreeding coefficients observed were 0.060; 0.084; 0.141; and 0.539; 0.562; 0.514, respectively, for the stocks of Campo Verde, Juína, and Nova Mutum. The Deviation in the Hardy-Weinberg equilibrium was observed in most of the loci in the three populations. Considering the genetic differentiation, it is concluded that the three populations are very close genetically, which requires introduction of new genetic material in the stocks to enrich them genetically for a later reproductive program.

With the rise of world fish farming, the national scenario is favorable for using native fish for intensive farming. Among the catfish, the Amazonian Jundiá (Leiarius marmoratus) is a robust candidate, easy to grow and with good organoleptic characteristics in its flesh. For productive success in captivity, it is necessary to consider some questions about the species, such as genetic variability, which must have an acceptable level in a breeding stock, in order to maintain a good diversity; this reduces losses due to inbreeding and low diversity. Therefore, the objective of this study was to characterize the genetic variability of commercial stocks of L. marmoratus from the State of Mato Grosso through microsatellite molecular markers. We analyzed 143 individuals from three stocks. The mean heterozygosity and the inbreeding coefficients observed were 0.060; 0.084; 0.141; and 0.539; 0.562; 0.514, respectively, for the stocks of Campo Verde, Juína, and Nova Mutum. The Deviation in the Hardy-Weinberg equilibrium was observed in most of the loci in the three populations. Considering the genetic differentiation, it is concluded that the three populations are very close genetically, which requires introduction of new genetic material in the stocks to enrich them genetically for a later reproductive program.

RESUMO

With the rise of world fish farming, the national scenario is favorable for using native fish for intensive farming. Among the catfish, the Amazonian Jundiá (Leiarius marmoratus) is a robust candidate, easy to grow and with good organoleptic characteristics in its flesh. For productive success in captivity, it is necessary to consider some questions about the species, such as genetic variability, which must have an acceptable level in a breeding stock, in order to maintain a good diversity; this reduces losses due to inbreeding and low diversity. Therefore, the objective of this study was to characterize the genetic variability of commercial stocks of L. marmoratus from the State of Mato Grosso through microsatellite molecular markers. We analyzed 143 individuals from three stocks. The mean heterozygosity and the inbreeding coefficients observed were 0.060; 0.084; 0.141; and 0.539; 0.562; 0.514, respectively, for the stocks of Campo Verde, Juína, and Nova Mutum. The Deviation in the Hardy-Weinberg equilibrium was observed in most of the loci in the three populations. Considering the genetic differentiation, it is concluded that the three populations are very close genetically, which requires introduction of new genetic material in the stocks to enrich them genetically for a later reproductive program.

With the rise of world fish farming, the national scenario is favorable for using native fish for intensive farming. Among the catfish, the Amazonian Jundiá (Leiarius marmoratus) is a robust candidate, easy to grow and with good organoleptic characteristics in its flesh. For productive success in captivity, it is necessary to consider some questions about the species, such as genetic variability, which must have an acceptable level in a breeding stock, in order to maintain a good diversity; this reduces losses due to inbreeding and low diversity. Therefore, the objective of this study was to characterize the genetic variability of commercial stocks of L. marmoratus from the State of Mato Grosso through microsatellite molecular markers. We analyzed 143 individuals from three stocks. The mean heterozygosity and the inbreeding coefficients observed were 0.060; 0.084; 0.141; and 0.539; 0.562; 0.514, respectively, for the stocks of Campo Verde, Juína, and Nova Mutum. The Deviation in the Hardy-Weinberg equilibrium was observed in most of the loci in the three populations. Considering the genetic differentiation, it is concluded that the three populations are very close genetically, which requires introduction of new genetic material in the stocks to enrich them genetically for a later reproductive program.

RESUMO

With the rise of world fish farming, the national scenario is favorable for using native fish for intensive farming. Among the catfish, the Amazonian Jundiá (Leiarius marmoratus) is a robust candidate, easy to grow and with good organoleptic characteristics in its flesh. For productive success in c aptivity, it is necessary to consider some questions about the species, such as genetic variability, which must have an acceptable level in a breeding stoc k, in order to maintain a good diversity; this reduces losses due to inbreeding and low diversity. Therefore, the objective of this study was to characterize the genetic variability of commercial stocks of L. marmoratusfrom the State of Mato Grosso through microsatellite molecular markers. We analyzed 143 individuals from three stocks. The mean hete rozygosity and the inbreeding coefficients observed were 0.060; 0.084; 0 .141; and 0.539; 0.562; 0.514, respectively, for the stocks of Campo V erde, Juína,and Nova Mutum. The Deviation in the Hardy-Weinberg equilib rium was observed in most of the lociin the three populations. Considering the genetic differentiation, it is concluded that the three populations are very clo se genetically, which requires introduction of new genetic material in the stock s to enrich them genetically for a later reproductive program.(AU)

Assuntos

RESUMO

ABSTRACT Brycon hilarii, popularly called piraputanga in Brazil, is a species distributed throughout the whole basin of the river Paraguay. In recent years, the species has been on a repopulation program due to its remarkable decline as a wild species in the region. Assessment of the genetic diversity of broodstock and fingerling stocks in repopulation programs is basic to avoid genetic impacts on wild populations. The genetic variability of the wild population and of the broodstock and fingerling stocks of B. hilarii in a repopulation program in the river Itiquira MT Brazil will be determined. Seven microsatellite loci produced 52 polymorphic alleles and heterozygosity revealed rates between 0.5794 and 0.7204. FIS did not register any endogamy in the broodstock but it was present in fingerlings and wild populations. Intra- and inter-specific genetic variability rates were higher within each combination but not between groups. Grouping in fingerling groups had a lower density when compared to the others. There is a higher genetic proximity between the natural population and broodstock (0.0237) when the distance between populations was analyzed, even though the two were greatly distant from the fingerling group (0.2622 - 0.2617). Results show that the wild population and the broodstock had high genetic variability and low genetic divergence; contrastingly, fingerlings showed mild genetic variability and great divergence when compared to other groups, indicating that they were not adequately constituted.

RESUMO

The objective of this work was to estimate the (co)variance and the genetic parameters for weight andaverage daily gain from two national generations of the GIFT strain of the Nile tilapia (Oreochromis niloticus). We evaluated 3918 fish from two generations of the breeding program from the Universidade Estadual de Maringá, Northwestern Paraná. Univariate and bivariate analysis were carried out using Bayesian inference. The estimates of heritability using one-trait models for weight was 0.15, average daily gain was 0.19, fish length was 0.23, fish width was 0.19, standard length was 0.17, fish heightwas 0.15, and the head length was 0.17. The genetic and phenotypic correlations were above 0.68and 0.95, respectively. The values of Spearman and Pearson correlations for breeding values of the morphometric traits in relation to average daily gain ranged from 0.58 to 0.98 and from 0.63 to 0.99, respectively. In the second generation (G2), the genetic gain was 2.6%, the effective size of thepopulation was 94, and the inbreeding coefficient was 0.005. In the next generation (G3), these valueswere 8.1%, 124 and 0.004, respectively. The genetic gains over the generations gradually increasedfrom one generation to another, indicating that the criterion, average daily gain, chosen for featureselection was efficient.(AU)

O objetivo deste trabalho foi estimar a (co) variância e os parâmetros genéticos para peso e ganho de peso médio diário de duas gerações de tilápia do Nilo (Oreochromis niloticus) linhagem GIFT. Foram avaliados 3.918 peixes por análise univariada e bivariada, utilizando inferência Bayesiana. As estimativas de herdabilidade usando modelos de análise unicaracteristica para o peso foi de 0,15 e para o ganho em peso médio diário foi de 0,19. Nas características morfométricas: comprimento total, comprimento padrão, largura, altura, tamanho da cabeça, os valores para herdabilidade foram de 0,23; 0,17; 0,19; 0,15 e 0,17 respectivamente. A correlação de Spearman e Pearson para os valores genéticos das características morfométricas em relação ao ganho de peso médio diário variaram de 0,58 a 0,98 e 0,63 a 0,99. Na segunda geração (G2), o ganho genético foi de 2,6%, o tamanho efetivo da população foi de 94, e coeficiente de endogamia foi de 0,005. Na geração (G3) estes valores foramde 8,1%, 124 e 0,004. As estimativas de (co) variância e parâmetros genéticos para peso e ganho de peso médio diário demonstraram que o ganho genético ao longo de gerações é gradual e crescente de uma geração para a outra indicando que o critério de seleção escolhido foi eficiente.(AU)

Assuntos

RESUMO

The objective of this work was to estimate the (co)variance and the genetic parameters for weight andaverage daily gain from two national generations of the GIFT strain of the Nile tilapia (Oreochromis niloticus). We evaluated 3918 fish from two generations of the breeding program from the Universidade Estadual de Maringá, Northwestern Paraná. Univariate and bivariate analysis were carried out using Bayesian inference. The estimates of heritability using one-trait models for weight was 0.15, average daily gain was 0.19, fish length was 0.23, fish width was 0.19, standard length was 0.17, fish heightwas 0.15, and the head length was 0.17. The genetic and phenotypic correlations were above 0.68and 0.95, respectively. The values of Spearman and Pearson correlations for breeding values of the morphometric traits in relation to average daily gain ranged from 0.58 to 0.98 and from 0.63 to 0.99, respectively. In the second generation (G2), the genetic gain was 2.6%, the effective size of thepopulation was 94, and the inbreeding coefficient was 0.005. In the next generation (G3), these valueswere 8.1%, 124 and 0.004, respectively. The genetic gains over the generations gradually increasedfrom one generation to another, indicating that the criterion, average daily gain, chosen for featureselection was efficient.

O objetivo deste trabalho foi estimar a (co) variância e os parâmetros genéticos para peso e ganho de peso médio diário de duas gerações de tilápia do Nilo (Oreochromis niloticus) linhagem GIFT. Foram avaliados 3.918 peixes por análise univariada e bivariada, utilizando inferência Bayesiana. As estimativas de herdabilidade usando modelos de análise unicaracteristica para o peso foi de 0,15 e para o ganho em peso médio diário foi de 0,19. Nas características morfométricas: comprimento total, comprimento padrão, largura, altura, tamanho da cabeça, os valores para herdabilidade foram de 0,23; 0,17; 0,19; 0,15 e 0,17 respectivamente. A correlação de Spearman e Pearson para os valores genéticos das características morfométricas em relação ao ganho de peso médio diário variaram de 0,58 a 0,98 e 0,63 a 0,99. Na segunda geração (G2), o ganho genético foi de 2,6%, o tamanho efetivo da população foi de 94, e coeficiente de endogamia foi de 0,005. Na geração (G3) estes valores foramde 8,1%, 124 e 0,004. As estimativas de (co) variância e parâmetros genéticos para peso e ganho de peso médio diário demonstraram que o ganho genético ao longo de gerações é gradual e crescente de uma geração para a outra indicando que o critério de seleção escolhido foi eficiente.

Assuntos

RESUMO

O objetivo do presente estudo foi analisar a diversidade genética de quatro linhagens de tilápia do Nilo (Oreochromis niloticus), utilizando o marcador RAPD. Foram coletadas amostras de nadadeira de estoques de juvenis das linhagens GIFT (G), Chitralada (C), Supreme (S) e Bouaké (B). Os 11 primers utilizados produziram 81 fragmentos dos quais 41,98% foram polimórficos. A porcentagem de fragmentos polimórficos (G: 18,52%; C: 19,75%; S: 20,99% e B: 24,79%) e os resultados do Gst confirmaram que houve alta (BxG: 0,231; BxC: 0,224; GxC: 0,194 e SxC: 0,208) e elevada (BxS: 0,315 e GxS: 0,270) diferenciação genética entre as linhagens. O fluxo gênico (Nm) foi maior entre as linhagens GxC (2,082). Os valores de distância e identidade genética (0,044 e 0,957 respectivamente) e o dendrograma indicam que as linhagens GxC são os mais semelhantes geneticamente. A similaridade genética foi alta dentro das linhagens (G: 0,932; C: 0,903; S: 0,891 e B: 0.900). Os resultados deste estudo possibilitarão o correto manejo reprodutivo e genético das linhagens.

The aim of this study was to analyze the genetic diversity of four Nile Tilapia (Oreochromis niloticus) strains using the RAPD marker. Fin samples of GIFT (G), Chitralada (C), Supreme (S) and Bouaké (B) juvenile stocks have been collected. The 11 primers used yielded 81 fragments of which 41.98% were polymorphic. The percentage of polymorphic loci (G: 18.52%; C: 19.75%; S: 20.99% and B: 24.79%) showed that there was a genetic differentiation among the strains, showing the Gst values a high (BxG: 0.231; BxC: 0.224; GxC: 0.194 and SxC: 0.208) and elevated (BxS: 0.315 and GxS: 0.270) differentiation. The highest gene flow (Nm) was among the GxC (2.082) strains. The distance and genetic identity values (0.044 and 0.957 respectively) and the dendrogram indicate that the GxC is the most genetically similar strains. The genetic similarity was high among of the strains (G: 0,932; C: 0,903; S: 0,891 AND B: 0.900). These results will enable a correct reproductive and genetic strains management.

Assuntos

RESUMO

O presente trabalho objetivou avaliar o desempenho produtivo de três linhagens de tilápia do Nilo (O. niloticus) na fase inicial e de crescimento, em diferentes densidades de estocagem. As linhagens estudadas foram Bouaké, Chitralada e GIFT. Foram utilizadas caixas dágua de 500 L, testando-se nove tratamentos e três repetições. Os parâmetros físicos e químicos da água mantiveram condições normais de cultivo para a espécie nas duas fases. Na fase inicial, ao se comparar entre as densidades dentro da mesma linhagem, não foram identificadas diferenças na Chitralada. Entretanto, as linhagens Bouaké e GIFT refletiram sensibilidade ao aumento das densidades de estocagem. Na fase de crescimento, os resultados obtidos para os parâmetros de desempenho médio final indicaram diferenças (p < 0,05) entre as densidades avaliadas dentro da mesma linhagem. Entretanto, quando comparadas às mesmas densidades entre as diferentes linhagens, não foram observadas diferenças significativas. Não foi observado desempenho superior de nenhuma das linhagens estudadas em função da densidade de estocagem.(AU)

The present work aimed to evaluate the productive performance of three Nile tilapia strains (O. niloticus) in the initial and of growth phases, in different stocking densities. The studied strains were Bouaké, Chitralada and GIFT. Five-hundred-liter tanks were used, testing nine treatments and three repetitions. The physical and chemical water parameters maintained normal conditions of cultivation for the species in both phases. In the initial phase, when comparing between the densities of the same strain, no differences were identified in Chitralada. However, the Bouaké and GIFT strains reflected sensibility to the increase in stocking densities. In the growth phase, the results obtained for the parameters of final medium performance indicate differences (p < 0.05) between the appraised densities within the same strain. However, when compared to the same densities between the different strains, significant differences were not observed. No best performance was observed for any of the strains studied in function of stocking density..(AU)

Assuntos

RESUMO

O presente trabalho objetivou avaliar o desempenho produtivo de três linhagens de tilápia do Nilo (O. niloticus) na fase inicial e de crescimento, em diferentes densidades de estocagem. As linhagens estudadas foram Bouaké, Chitralada e GIFT. Foram utilizadas caixas d’água de 500 L, testando-se nove tratamentos e três repetições. Os parâmetros físicos e químicos da água mantiveram condições normais de cultivo para a espécie nas duas fases. Na fase inicial, ao se comparar entre as densidades dentro da mesma linhagem, não foram identificadas diferenças na Chitralada. Entretanto, as linhagens Bouaké e GIFT refletiram sensibilidade ao aumento das densidades de estocagem. Na fase de crescimento, os resultados obtidos para os parâmetros de desempenho médio final indicaram diferenças (p < 0,05) entre as densidades avaliadas dentro da mesma linhagem. Entretanto, quando comparadas às mesmas densidades entre as diferentes linhagens, não foram observadas diferenças significativas. Não foi observado desempenho superior de nenhuma das linhagens estudadas em função da densidade de estocagem.

The present work aimed to evaluate the productive performance of three Nile tilapia strains (O. niloticus) in the initial and of growth phases, in different stocking densities. The studied strains were Bouaké, Chitralada and GIFT. Five-hundred-liter tanks were used, testing nine treatments and three repetitions. The physical and chemical water parameters maintained normal conditions of cultivation for the species in both phases. In the initial phase, when comparing between the densities of the same strain, no differences were identified in Chitralada. However, the Bouaké and GIFT strains reflected sensibility to the increase in stocking densities. In the growth phase, the results obtained for the parameters of final medium performance indicate differences (p < 0.05) between the appraised densities within the same strain. However, when compared to the same densities between the different strains, significant differences were not observed. No best performance was observed for any of the strains studied in function of stocking density..

Assuntos