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Fish protein hydrolysates (FPHs) can be obtained from substrates such as fish muscle, skin, and wastes and assign value to these fish by-products. Proteolytic enzymes catalyze the hydrolysis of these fish substrates' peptide bonds resulting in smaller peptides that present several bioactive properties. Hydrolysates' bioactive properties are a function of the fish species used as the substrate, the enzyme selectivity or specificity, pH and temperature applied in the reaction, etc. Furthermore, many pre-treatment methods are being applied to fish protein substrates to improve their enzyme susceptibility and increase the number of smaller bioactive peptides. This review addresses the production of FPHs and the main bioactive properties evaluated recently in the literature and emphasizes the substrate treatments by high-pressure processing, microwave, ultrasound, and thermal treatments to achieve better bioactivity making essential amino acids more available in peptides. The bioactive properties most found in FPHs were antioxidants, antimicrobials, anticancer, and antihypertensive. These bioactivities may vary depending on the conditions of hydrolysis, fish species, and fractionation and isolation of specific peptides.New technologies for the treatment of by-products can reduce process losses and achieve better results by cleavage of proteins. Conversely, encapsulation and film utilization can improve bioactivity, bioavailability, and controlled release when applied to foods, resulting in improved health.

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The development and intensification of tilapia farming depends on the manipulation of some physiological functions, such as the sexual inversion of larvae using a synthetic androgen (17α-methyltestosterone). This inversion, however, may represent a potential oxidative stress factor and cause damage to animals in the short, medium, and long term. Dietary supplementation of natural antioxidant compounds is an interesting alternative to combat such damage. To test this hypothesis, an experimental trial was carried out involving sexual inverted and non-inverted Nile tilapia fingerlings, both supplemented and not supplemented with a blend of organic acids and essential oils protected by microencapsulation. Animals were divided into four experimental groups: NI (non-inverted animals), I (sexual inverted animals), NI + M (non-inverted animals supplemented with microcapsules), and I + M (sexual inverted animals supplemented with microcapsules). Blood parameters (WBC - white blood cells; LY - lymphocytes; RBC - red blood cells; HGB - hemoglobin; HCT - hematocrit number; MCH - mean corpuscular hemoglobin; MCV - mean corpuscular volume and MCHC - mean corpuscular hemoglobin concentration), as well as oxidative stress markers (enzymatic activity of superoxide dismutase - SOD and catalase - CAT; and total antioxidant capacity - 2,2-diphenyl-1-picryl-hydrazyl (DPPH)) and gene expression (heat shock protein 70 kDa - HSP70) were evaluated. The HGB (p < 0.001) and HCT (p = 0.005) parameters were reduced beyond the recommended limits for the animals in group I. The MCV varied statistically between the groups (p < 0.001). However, all values were within the recommended range for the species, jointly indicating normocytic anemia in group I fingerlings at the time of collection. The activity of CAT and SOD, as well as DPPH differed statistically between the experimental groups (p < 0.001), with the lowest SOD and CAT activity, as well as the highest DPPH registered in animals supplemented with microcapsules. The expression of HSP70 was lower in I + MI animals (p < 0.001). The synergistic evaluation of the results indicates that animals sexual inverted during the larval stage have a lower total antioxidant capacity in the fingerling stage, which reflects a worsening in hematological and enzymatic parameters related to immunity; and that dietary supplementation with blend of organic acids and essential oils protected by microencapsulation is sufficient to improve the immunological response both in sexual inverted and non-inverted fingerlings.

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Variance components and heritabilities for daily weight gain (DWG) were estimated for Nile tilapia farmed in cages across nine generations (G1-G9) of selection in a breeding program in Brazil. DWG was measured in 16,272 accumulated tagged animals representing 535 full- and half-sib families of Nile tilapia under cage farming. The additive genetic variance showed a slight variation (0.051-0.066), and heritability estimates ranged from 0.20 to 0.33. The common environmental effect accounted for a higher proportion of the total variance in DWG, especially in the last generations (6%-24%). A genetic trend based on all data available showed a substantial increase in the DWG (about 3.3% per generation) of Nile tilapia across nine generations of selection. Furthermore, our results demonstrate ample scope for further genetic improvement.

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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)

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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.(AU)

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Digital image analysis is a practical, non-invasive, and relatively low-cost tool that may assist in the evaluation of body traits in Nile tilapia, being particularly useful for assessing difficult-to-measure variables, such as body areas. In this study, we aimed to estimate variance components and genetic parameters for body areas of Nile tilapia obtained by digital images. The data set comprised body weight (BW) records of 1,917 pond-reared fish at 366 days of age. Of this total, 656 animals were photographed and subjected to image analysis of trunk area (TA), head area (HA), caudal fin area (CFA) and fillet area (FA). Heritabilities and genetic correlations were estimated through multiple-trait models based on Bayesian inference. Heritability estimates for BW, TA, HA, CFA and FA were 0.25, 0.23, 0.26, 0.21 and 0.25, respectively. Genetic correlations between the traits were high and positive, ranging from 0.70 to 0.98. We highlight the genetic correlation between BW and TA (rG  = 0.98) and FA (rG  = 0.97). In view of the observed results, it can be concluded that trunk and fillet areas obtained by digital image analysis can lead to indirect genetic gains in weight and other body areas. In addition, the areas studied have potential as a selection criterion and may assist in studies on changes in the body shape in Nile tilapia.

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This study evaluated the effect of methionine supplementation, predation risk and their interaction on gut histology, whole-body cortisol levels, and intestinal gene expression in zebrafish. A total of 360 one-year-old animals were maintained under two environmental conditions and fed diets containing different methionine sources. Fish were fed either a control diet (CTL, without methionine supplementation), a diet supplemented with dl-methionine (DLM), or a diet supplemented with methionine dipeptide (MM) in the absence (AP) of a predator or in the presence of the predator (PP) for 48 h or 20 days. Predator-induced stress for 20 days resulted in lower body weight. Zebrafish fed methionine-supplemented diets had higher weight gain than control fish. We found no effect of predation stress or methionine supplementation on cortisol level. Predation risk and methionine supplementation showed no interaction effect on dipeptide transporter gene expression. After 48 h of predation pressure, zebrafish had higher mRNA expression of SOD2, CAT and GPX1 in the gut. After 20 days of exposure to the predator, zebrafish fed methionine-supplemented diets had lower expression of GPX1, SOD2 and CAT than those diet CTL. Methionine dipeptide and free methionine supplementation improved growth, intestinal health and survivability of zebrafish both conditions.

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Studies on genetic composition in fish populations contribute to conservationist practices and inbreeding control in fish stocks. To this end, molecular tools such as microsatellite markers (SSRs) are often used, but they are expensive and time-consuming to develop. A species-specific heterologous marker emerges as an alternative, which can be used in taxonomically related species in a fast way. Our goal was to test SSRs markers of Brachyplatystoma rousseauxi and Pseudoplatystoma punctifer in P. reticulatum in an unprecedented way. For this purpose, DNA was extracted from fragments of the caudal fin of 222 P. reticulatum adults, using a NaCl-based method. Then, DNA samples were amplified by Polymerase Chain Reaction (PCR) using six markers, four from B. rousseauxi (BR38, 47, 51, and 61) and two from P. punctifer (PPU13 and PPU15). Two primers showed non-specific amplification and were disregarded (BR38 and PPU13). In the remaining four primers, the number of alleles per locus varied between two (BR47) to sixteen (BR51), and the average size of alleles was between 142 and 400 bp. Mean effective number of alleles per locus ranged from 10,650 (BR51) to 1,784 (BR47), with null or low-frequency alleles in all studied loci. Observed heterozygosity ranged from 0.299 (BR47) to 0.640 (BR51) and was always lower than the expected heterozygosity. Hardy-Weinberg balance was significant (p < 0.05) in all loci, and inbreeding coefficient (FIS) was always positive. Polymorphic Information Content (PIC) confirmed the efficiency of the markers since they had moderate (BR47) to high levels of information (BR51, BR61, and PPU15). Transferability test showed that the heterologous microsatellite molecular markers, originally for B. rousseauxi and P. punctifer, were efficient in P. reticulatum, producing three primers with high information content. Therefore, these markers can be safely used in future population studies of this species.(AU)

Estudos acerca da composição genética de populações de peixes contribuem para a elaboração de práticas conservacionista, bem como para controle da consanguinidade em estoques de piscicultura. Neste sentido, ferramentas moleculares como os marcadores microssatélites (SSR's) são comumente utilizados, contudo, seu desenvolvimento corresponde a um processo caro e demorado. Surge como alternativa a utilização dos marcadores heterólogos, originalmente desenvolvidos para uma espécie, mas que podem ser utilizados de maneira rápida em outras taxonomicamente relacionadas. O objetivo desta pesquisa foi testar de maneira inédita a utilização de marcadores SSR's de Brachyplatystoma rousseauxi e Pseudoplatystoma punctifer em P. reticulatum. Para tanto, foram extraídas amostras de DNA a partir de fragmentos de nadadeira caudal de 222 indivíduos adultos de P. reticulatum por metodologia a base de NaCl. As amostras foram então amplificadas por Reação em Cadeia da Polimerase (PCR) utilizandose seis marcadores, quatro de B. rousseauxi (BR38, 47, 51 e 61) e dois de P. punctifer (PPU13 e PPU15). Dois primers apresentaram amplificação inespecífica e foram desconsiderados (BR38 e PPU13). Entre os quatro restantes, o número de alelos por locus variou entre dois (BR47) a dezesseis (BR51), com tamanho médio de alelos entre 142 e 400 pb. O número efetivo médio de alelos por locus variou de 10,650 (BR51) à 1,784 (BR47), com alelos nulos ou de baixa frequência presentes em todos os loci estudados. Os valores de heterozigosidade observada variaram de 0,299 (BR47) à 0,640 (BR51), e foram sempre menores que os de heterozigosidade esperada. O Equilíbrio de Hardy-Weinberg foi significativo (P < 0,05) em todos os locus e o coeficiente de endogamia Fis sempre apresentou valores positivos. Os valores de Conteúdo de Informação Polimórfica (PIC) confirmaram a eficiência dos marcadores utilizados, já que possuíram de moderado (BR47) a alto nível de informação (BR51, BR61 e PPU15). O teste de transferibilidade de marcadores moleculares microssatélites heterólogos, originalmente desenvolvidos para B. rousseauxi e P. punctifer em P. reticulatum se mostrou eficiente, produzindo três primers com alto nível de informação, fato que garante sua utilização segura em estudos populacionais futuros voltados à esta espécie.(AU)

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Nile tilapia (Oreochromis niloticus) is the major fish species produced in Brazil, a country with a vast territory and great climate diversity. This study assessed the effects of the genotype × environment interaction on heritability estimates and selection responses in Nile tilapia (Tilamax strain) cultivated in earthen ponds and net cages. The weight at harvest, trunk length, and head percentage of 4400 individuals were determined. Trait heritabilities were higher in pond fish (0.27-0.52) than in caged fish (0.09-0.33). Genetic correlations between farming systems were lower than 0.5 for the three traits. The rank position of the top 10 families differed according to the environment, as did the response to direct and indirect selection. The results revealed significant genotype × environment effects on the heritability of Nile tilapia farmed under different systems.

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The Amazonian fish Tambaqui (Colossoma macropomum) is the most common native species in Brazil. This species has the highest production rate in the Northern region, especially in the State of Rondônia. The genetic evaluation of Tambaqui is an extremely important to increase productivity in fish farms or improve the adaptability in restocking natural populations. The objective of this study was to evaluate the genetic diversity of three Tambaqui broodstocks in Rondônia, Brazil. Six microsatellite markers were used to analyze a total of 89 breeders collected from three fish farms located in Ji-Paraná (JP), Ouro Preto do Oeste (OP) and Presidente Médici (PM). A total of 37 alleles between 140 and 310 bp were found, including the presence of exclusive and low frequency alleles in the three broodstocks. The average values of observed heterozygosity ranged from 0.404 (PM) to 0.499 (JP). The FIS coefficient values were positive for the three broodstocks, demonstrating a deficit of heterozygotes. The Molecular Variance Analysis (AMOVA) showed greater variation within the stocks than between them. The genetic differentiation was moderate and significant between the stocks, with higher differentiation between JP x PM and lower between OP x PM. The Bayesian analysis designated an optimal value of K=3 groupings. Although there is moderate genetic diversity between broodstocks, the high FIS indicates a possible decline of diversity in the next generations, and therefore, the incorporation of new breeders is suggested to increase the genetic diversity in the three stocks.(AU)

O peixe amazônico Tambaqui (Colossoma macropomum) é a espécie nativa mais produzida no Brasil. Esta espécie é a mais criada na região Norte, principalmente no Estado de Rondônia. A avaliação genética de Tambaqui é extremamente importante para aumentar a produtividade nas pisciculturas ou melhorar a adaptabilidade no repovoamento de populações naturais. O objetivo deste estudo foi avaliar a diversidade genética de três estoques de Tambaqui em Rondônia, Brasil. Seis marcadores microssatélites foram utilizados para analisar um total de 89 reprodutores coletados em três pisciculturas localizadas em Ji-Paraná (JP), Ouro Preto do Oeste (OP) e Presidente Médici (PM). Foram encontrados 37 alelos entre 140 e 310 pb, incluindo a presença de alelos exclusivos e de baixa frequência nas três ninhadas. Os valores médios de heterozigosidade observada variaram de 0,404 (PM) a 0,499 (JP). Os valores do coeficiente de FIS foram positivos para as três ninhadas, demonstrando déficit de heterozigotos. A Análise de Variância Molecular (AMOVA) mostrou maior variação dentro dos estoques do que entre eles. A diferenciação genética foi moderada e significativa entre os estoques, com maior diferenciação entre JPxPM e menor entre OP x PM. A análise bayesiana designou um valor ótimo de K = 3 agrupamentos. Embora exista uma diversidade genética moderada entre os filhotes, o alto SIF indica um possível declínio da diversidade nas próximas gerações e, portanto, sugere-se a incorporação de novos criadores para aumentar a diversidade genética nos três estoques.(AU)

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The Amazonian fish Tambaqui (Colossoma macropomum) is the most common native species in Brazil. This species has the highest production rate in the Northern region, especially in the State of Rondônia. The genetic evaluation of Tambaqui is an extremely important to increase productivity in fish farms or improve the adaptability in restocking natural populations. The objective of this study was to evaluate the genetic diversity of three Tambaqui broodstocks in Rondônia, Brazil. Six microsatellite markers were used to analyze a total of 89 breeders collected from three fish farms located in Ji-Paraná (JP), Ouro Preto do Oeste (OP) and Presidente Médici (PM). A total of 37 alleles between 140 and 310 bp were found, including the presence of exclusive and low frequency alleles in the three broodstocks. The average values of observed heterozygosity ranged from 0.404 (PM) to 0.499 (JP). The FIS coefficient values were positive for the three broodstocks, demonstrating a deficit of heterozygotes. The Molecular Variance Analysis (AMOVA) showed greater variation within the stocks than between them. The genetic differentiation was moderate and significant between the stocks, with higher differentiation between JP x PM and lower between OP x PM. The Bayesian analysis designated an optimal value of K=3 groupings. Although there is moderate genetic diversity between broodstocks, the high FIS indicates a possible decline of diversity in the next generations, and therefore, the incorporation of new breeders is suggested to increase the genetic diversity in the three stocks.

O peixe amazônico Tambaqui (Colossoma macropomum) é a espécie nativa mais produzida no Brasil. Esta espécie é a mais criada na região Norte, principalmente no Estado de Rondônia. A avaliação genética de Tambaqui é extremamente importante para aumentar a produtividade nas pisciculturas ou melhorar a adaptabilidade no repovoamento de populações naturais. O objetivo deste estudo foi avaliar a diversidade genética de três estoques de Tambaqui em Rondônia, Brasil. Seis marcadores microssatélites foram utilizados para analisar um total de 89 reprodutores coletados em três pisciculturas localizadas em Ji-Paraná (JP), Ouro Preto do Oeste (OP) e Presidente Médici (PM). Foram encontrados 37 alelos entre 140 e 310 pb, incluindo a presença de alelos exclusivos e de baixa frequência nas três ninhadas. Os valores médios de heterozigosidade observada variaram de 0,404 (PM) a 0,499 (JP). Os valores do coeficiente de FIS foram positivos para as três ninhadas, demonstrando déficit de heterozigotos. A Análise de Variância Molecular (AMOVA) mostrou maior variação dentro dos estoques do que entre eles. A diferenciação genética foi moderada e significativa entre os estoques, com maior diferenciação entre JPxPM e menor entre OP x PM. A análise bayesiana designou um valor ótimo de K = 3 agrupamentos. Embora exista uma diversidade genética moderada entre os filhotes, o alto SIF indica um possível declínio da diversidade nas próximas gerações e, portanto, sugere-se a incorporação de novos criadores para aumentar a diversidade genética nos três estoques.

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In recent years, anthropogenic factors such as pollution, overfishing, and construction of hydroelectric plants have significantly impacted natural fish populations. Research focusing on genetically evaluation of these impacts is necessary to objectively target conservation programs. The aim of this study was to evaluate the genetic diversity of Curimba (Prochilodus lineatus), Pacu (Piaractus mesopotamicus), and Piracanjuba (Brycon orbignyanus) populations from the Água Vermelha Reservoir, Rio Grande-SP. Microsatellite loci were amplified, producing 56, 24, and 26 alleles for the populations of the three species, respectively. The number of alleles per locus ranged from three to ten for P. lineatus, two to five for P. mesopotamicus, and two to four for B. orbignyanus. The observed heterozygosity (Ho) was higher in the P. lineatus population (0.547), relative to the P. mesopotamicus and B. orbignyanus populations (0.473 and 0.527, respectively). The mean values of Ho were lower than the average expected heterozygosity (He) in the three species, being corroborated by the positive inbreeding coefficient (Fis). Deviations from the Hardy-Weinberg equilibrium (HWE) were found in five, three, and two loci for P. lineatus, P. mesopotamicus, and B. orbignyanus, respectively. Wilcoxon tests revealed recent bottlenecks in the three species, evidenced by a significant excess of heterozygotes (p < 0.05) detected only in the Infinite Allele Model (IAM). In conclusion, adequate genetic variability was observed in the three populations with the presence of heterozygous deficits.(AU)

Nos últimos anos, fatores antrópicos como poluição, sobrepesca e construção de hidrelétricas têm impactado significativamente as populações naturais de peixes. Pesquisas que permitam avaliar geneticamente esse impacto são necessárias para orientar objetivamente programas de conservação. O objetivo do presente estudo foi avaliar a diversidade genética de populações de Curimba (Prochilodus lineatus), Pacu (Piaractus mesopotamicus) e Piracanjuba (Brycon orbignyanus) provenientes do reservatório de Água Vermelha, Rio Grande-SP. Foram amplificados loci microssatélites que produziram 56, 24 e 26 alelos para as populações das três espécies, respectivamente. O número de alelos por locus variou de três a dez para P. lineatus, dois a cinco para P. mesopotamicus e dois a quatro para B. orbignianus. A heterozigosidade observada (Ho) foi mais elevada na população de P. lineatus (0,547) em relação às populações de P. mesopotamicus e B. orbignyanus (0,473 e 0,527, respectivamente). A média dos valores de Ho foram inferiores à média de He nas três espécies sendo corroborado pelo Fis positivo observado. Foi encontrado desvio do equilíbrio de Hardy-Weinberg (HWE) em cinco loci para P. lineatus, três loci para P. mesopotamicus e dois em B. orbignyanus. A análise de bottleneck revelou excesso de heterozigotos (p<0,05) pelo teste de Wilcoxon nas três espécies apenas no modelo Infinite Allele Model (IAM). Foi observada adequada variabilidade genética nas três populações com a presença de déficit de heterozigotos.(AU)

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The objective of this study was to evaluate the effect of oxidative stress on the instrumental and sensory quality of Nile tilapia fillets. The experiment was conducted in a 2x2 factorial arrangement, evaluating densities (60 and 300 kg m-3) and depuration times (1 and 24 hours) in a total of four treatments. The serum levels of cortisol and gene expression levels of catalase (CAT), glutathione peroxidase (GPx) and 70 kDa heat shock protein (HSP70) as well as the pH, color, tenderness, water-holding capacity and sensory analysis of the fillets were evaluated. High density (300 kg m-3) resulted in higher mean cortisol levels, lower expression of CAT and GPx enzymes as well as higher expression of HSP70. Fish under this treatment also exhibited fillets with greater tenderness, higher lightness, lower redness and lower sensory acceptance. The longer depuration time (24 hours) resulted in lower expression of the CAT and GPx enzymes and fillets with higher lightness. The water-holding capacity was not affected by the different treatments. Therefore, low density and longer depuration times are recommended for decreased stress and improved quality of fillets.

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O objetivo desta revisão é descrever as características dos surubins e a implantação do programa de melhoramento genético da espécie Pseudoplatystoma reticulatum durante o período de 2008 a 2013. O Pseudoplatystoma reticulatum ou cachara é uma das espécies nativas potenciais para aquicultura brasileira. O cultivo concentra-se na região Centro-Oeste onde os fatores: adaptabilidade ao ambiente, características zootécnicas e alto valor comercial tornam viável a produção. A espécie possui estudos consolidados em biotécnicas de reprodução, desenvolvimento e adaptação aos vários sistemas de cultivos. As regiões produtoras dispõem de oferta contínua de alevinos, aumentando o potencial de consolidação de programas de melhoramento genético com a espécie. Com isso, foi desenvolvida uma parceria entre a Embrapa e a Universidade Estadual de Maringá, com a finalidade de desenvolver o programa de melhoramento genético do cachara. O programa de melhoramento genético do cachara iniciou em 2008 com a formação de 72 famílias e teve seu término em 2013 sob os moldes originais de gestão.(AU)

The objective of this review is to describe the characteristics of the surubins and the implantation of the breeding program of the species Pseudoplatystoma reticulatum during the period 2008 - 2013. Pseudoplatystoma reticulatum or cachara is one of the species onances potential for Brazilian aquaculture. The culture is concentrated in the Center-West region, where the factors: adaptability to the environment, zootechnical characteristics and high commercial value become viable the production. This study studies for the consolidation of biotechnology of production, development and vapour attentive systems of cultures. Content-producing regions continued in succession, increasing the potential for consolidation of gender-breeding programs. With this was a partnership between Embrapa and the Universidade Estadual de Maringá, with the purpose of developing the programs of genetic improvement of cachara. The breeding program cachara started in 2008 with the formation of 72 families had its end in 2013 under the original management molds.(AU)

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This study evaluated morphometric and ultrasound information of tilapia (O. niloticus) breeders through multivariate analysis. We applied correlation, clustering, and principal component analysis to a dataset composed of information from 222 male and female breeders of the improved GIFT strain. The body weight, objective of the breeding program, showed a high positive correlation with most of the morphometric parameters. The formation of clusters indicated characteristics responsible for muscle composition and carcass weight. Some characteristics showed a high correlation, such as body weight and fillet weight (0.98 and 0.94 for females and males, respectively), and a high contribution to the explanation of data variability; of the total characteristics evaluated for females, two explained 75% data variability and four explained 72% for males. We concluded that it is possible to reduce the number of characteristics measured, as well as use information of average daily weight gain and body weight to select female and male breeders, respectively, to drive genetic gains favoring more productive generations.(AU)

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In recent years, anthropogenic factors such as pollution, overfishing, and construction of hydroelectric plants have significantly impacted natural fish populations. Research focusing on genetically evaluation of these impacts is necessary to objectively target conservation programs. The aim of this study was to evaluate the genetic diversity of Curimba (Prochilodus lineatus), Pacu (Piaractus mesopotamicus), and Piracanjuba (Brycon orbignyanus) populations from the Água Vermelha Reservoir, Rio Grande-SP. Microsatellite loci were amplified, producing 56, 24, and 26 alleles for the populations of the three species, respectively. The number of alleles per locus ranged from three to ten for P. lineatus, two to five for P. mesopotamicus, and two to four for B. orbignyanus. The observed heterozygosity (Ho) was higher in the P. lineatus population (0.547), relative to the P. mesopotamicus and B. orbignyanus populations (0.473 and 0.527, respectively). The mean values of Ho were lower than the average expected heterozygosity (He) in the three species, being corroborated by the positive inbreeding coefficient (Fis). Deviations from the Hardy-Weinberg equilibrium (HWE) were found in five, three, and two loci for P. lineatus, P. mesopotamicus, and B. orbignyanus, respectively. Wilcoxon tests revealed recent bottlenecks in the three species, evidenced by a significant excess of heterozygotes (p < 0.05) detected only in the Infinite Allele Model (IAM). In conclusion, adequate genetic variability was observed in the three populations with the presence of heterozygous deficits.

Nos últimos anos, fatores antrópicos como poluição, sobrepesca e construção de hidrelétricas têm impactado significativamente as populações naturais de peixes. Pesquisas que permitam avaliar geneticamente esse impacto são necessárias para orientar objetivamente programas de conservação. O objetivo do presente estudo foi avaliar a diversidade genética de populações de Curimba (Prochilodus lineatus), Pacu (Piaractus mesopotamicus) e Piracanjuba (Brycon orbignyanus) provenientes do reservatório de Água Vermelha, Rio Grande-SP. Foram amplificados loci microssatélites que produziram 56, 24 e 26 alelos para as populações das três espécies, respectivamente. O número de alelos por locus variou de três a dez para P. lineatus, dois a cinco para P. mesopotamicus e dois a quatro para B. orbignianus. A heterozigosidade observada (Ho) foi mais elevada na população de P. lineatus (0,547) em relação às populações de P. mesopotamicus e B. orbignyanus (0,473 e 0,527, respectivamente). A média dos valores de Ho foram inferiores à média de He nas três espécies sendo corroborado pelo Fis positivo observado. Foi encontrado desvio do equilíbrio de Hardy-Weinberg (HWE) em cinco loci para P. lineatus, três loci para P. mesopotamicus e dois em B. orbignyanus. A análise de bottleneck revelou excesso de heterozigotos (p<0,05) pelo teste de Wilcoxon nas três espécies apenas no modelo Infinite Allele Model (IAM). Foi observada adequada variabilidade genética nas três populações com a presença de déficit de heterozigotos.

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O objetivo desta revisão é descrever as características dos surubins e a implantação do programa de melhoramento genético da espécie Pseudoplatystoma reticulatum durante o período de 2008 a 2013. O Pseudoplatystoma reticulatum ou cachara é uma das espécies nativas potenciais para aquicultura brasileira. O cultivo concentra-se na região Centro-Oeste onde os fatores: adaptabilidade ao ambiente, características zootécnicas e alto valor comercial tornam viável a produção. A espécie possui estudos consolidados em biotécnicas de reprodução, desenvolvimento e adaptação aos vários sistemas de cultivos. As regiões produtoras dispõem de oferta contínua de alevinos, aumentando o potencial de consolidação de programas de melhoramento genético com a espécie. Com isso, foi desenvolvida uma parceria entre a Embrapa e a Universidade Estadual de Maringá, com a finalidade de desenvolver o programa de melhoramento genético do cachara. O programa de melhoramento genético do cachara iniciou em 2008 com a formação de 72 famílias e teve seu término em 2013 sob os moldes originais de gestão.

The objective of this review is to describe the characteristics of the surubins and the implantation of the breeding program of the species Pseudoplatystoma reticulatum during the period 2008 - 2013. Pseudoplatystoma reticulatum or cachara is one of the species onances potential for Brazilian aquaculture. The culture is concentrated in the Center-West region, where the factors: adaptability to the environment, zootechnical characteristics and high commercial value become viable the production. This study studies for the consolidation of biotechnology of production, development and vapour attentive systems of cultures. Content-producing regions continued in succession, increasing the potential for consolidation of gender-breeding programs. With this was a partnership between Embrapa and the Universidade Estadual de Maringá, with the purpose of developing the programs of genetic improvement of cachara. The breeding program cachara started in 2008 with the formation of 72 families had its end in 2013 under the original management molds.

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This study evaluated pre-slaughter stress and its influence on the stress indicators, quality characteristics and sensory characteristics of Nile tilapia fillets. To this end, two experiments were conducted: (1) two transportation times (60 and 240 min), with a density of 200 kg m−3, were compared to control treatment fish (in which the fish were removed from the net cage and immediately euthanized); and (2) two transportation densities (100 and 400 kg m−3), transported for 180 min, compared with control treatment fish. In experiment 1, the transportation time of 60 min resulted in higher levels of serum cortisol and plasma glucose compared to the transportation time of 240 min and the control. Fish fillets transported for 240 min had higher water-holding capacity, less water loss by pressure and higher levels of juiciness compared to fish transported for 60 min. Color, pH and water loss during cooking were not affected by transportation time. In experiment 2, transportation densities of 100 and 400 kg m−3 did not significantly affect the stress indicators nor the instrumental quality parameters of the fillets, but fish transported at 400 kg m−3 showed better visual acceptance by panellists.(AU)

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