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UNLABELLED: This systematic review and meta-analysis of randomized controlled trials (RCTs) identified significant effects of whole body vibration (WBV) on bone mineral density (BMD) of the lumbar spine (in the sensitivity analysis and seven subgroup analyses), femoral neck (in one subgroup analysis), and trochanter (four subgroup analyses) in postmenopausal women, but not other measurements of BMD. INTRODUCTION: Interventions using WBV training have been conducted in postmenopausal women, aimed at increasing BMD; however, the results are contradictory. Our objective is to conduct a systematic review and meta-analysis of RCTs examining WBV effect on BMD. METHODS: RCTs were considered eligible, with follow-up ≥6 months, which verified the effects of WBV on the BMD of postmenopausal women. The calculations of the meta-analysis were performed through the weighted mean difference between the WBV and control groups, or the WBV and combined training, through the absolute change between pre- and post-intervention in the areal bone mineral density (aBMD) or trabecular volumetric bone mineral density (vBMDt). RESULTS: Fifteen RCTs were included in the meta-analysis. No differences were observed in the primary analysis. WBV was found to improve aBMD compared with the control group, after exclusion of studies with low quality methodological (lumbar spine), when excluding the studies which combined WBV with medication or combined training (lumbar spine), with the use of low frequency and high magnitude (lumbar spine and trochanter), high frequency and low magnitude (lumbar spine), high cumulative dose and low magnitude (lumbar spine), low cumulative dose and high magnitude (lumbar spine and trochanter), with semi-flexed knee (lumbar spine, femoral neck, and trochanter), and side-alternating type of vibration (lumbar spine and trochanter). CONCLUSIONS: Despite WBV presenting potential to act as a coadjuvant in the prevention or treatment of osteoporosis, especially for aBMD of the lumbar spine, the ideal intervention is not yet clear. Our subgroup analyses helped to demonstrate the various factors which appear to influence the effects of WBV on BMD, contributing to clinical practice and the definition of protocols for future interventions.

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Knowledge of genetic diversity and relationships between breeds is very important for conservation programs. Hair samples were collected from 393 individual Nordestino horses and genotyped using 14 microsatellite markers in order to investigate the genetic relationship between this breed and 66 international horse breeds. There was high allelic diversity and inbreeding coefficient within population values were not significant, which was probably due to crossbreeding. Despite the Nordestino horse population being in Hardy-Weinberg equilibrium, a global deficit of heterozygotes was observed. This may represent evidence of repeated use of the same stallions for breeding, which is consistent with the high number of castrated males found. Campolina, Mangalarga Marchador, and Mangalarga were the Brazilian horse breeds most closely related to the Nordestino horse, which is a reflection of recent introgressions. Among Iberian horse breeds, the Sorraia breed appears to have had an important influence on the genetics of the Nordestino horse. Those results provide important information that can guide future conservation programs.

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Para avaliar a viabilidade da metodologia da Reação em Cadeia da Polimerase associada com o Polimorfismo de Fragmentos de DNA (PCR-RFLP) na identificação de fraude intencional e contaminação acidental em produtos cárneos de origem bubalina, in natura e processados, foram testadas amostras puras e amostras de carnes com misturas controladas, produzidas em laboratório, com adição de 1%, 5%, 10% e 50% de carne bovina em carne de búfalo, homogeneizada crua e em amostras autoclavada. Foram comparados, ainda, diferentes métodos de extração, usando um kit comercial e a técnica clássica, utilizando fenol/clorofórmio. O resultado estatístico foi obtido por tabela de contingência, analisada pelo teste do qui-quadrado (2) e do exato de Fisher. A especificidade encontrada foi altamente significativa (P<0,0001). Observou-se também sensibilidade altamente significativa nas diluições a partir de 10% (P<0,0001). A técnica tem alta especificidade e sensibilidade para detectar até mesmo contaminação de 1%, mas a repetibilidade desse resultado impede a aplicação oficial desse método para a inspeção de contaminação acidental, sendo recomendada somente para inspeção de fraude a partir de 10% de substituição. Em carnes autoclavadas, a eficácia do teste é menor. A técnica pode ser empregada para certificação de produto específico (selo de identidade de espécie).(AU)

The present study aimed at evaluate the viability of PCR-RFLP (Polymerase Chain Reaction - Restriction Fragment Length Polymorphism) for identification of fraud and/or accidental contamination in buffalo meat - fresh and processed. Pure, autoclaved and controlled fraud samples, produced in the laboratory with the addition of 1, 5, 10 and 50% of beef in raw homogenized buffalo meat samples, were tested. Furthermore, different extraction methods, using a commercial kit and classical technique using phenol-chloroform, were compared. The statistical result was obtained by contingency table analyzed by chi-square and the Fisher exact test. The specificity was highly significant (p <0.0001), and the sensitivity was highly significant in dilutions from 10% (p <0.0001). Despite its accuracy and precision, capable to detect a contamination level of 1%, PCR-RFLP technique is not recommended for inspection in cases of accidental contamination. This is due to the need of test repetition in levels of contamination lower than 10%. The efficiency of this test is lower to autoclaved meat. The PCR-RFPL technique can be used for certification of food made with specific species (species identification certification stamp).(AU)

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Para avaliar a viabilidade da metodologia da Reação em Cadeia da Polimerase associada com o Polimorfismo de Fragmentos de DNA (PCR-RFLP) na identificação de fraude intencional e contaminação acidental em produtos cárneos de origem bubalina, in natura e processados, foram testadas amostras puras e amostras de carnes com misturas controladas, produzidas em laboratório, com adição de 1%, 5%, 10% e 50% de carne bovina em carne de búfalo, homogeneizada crua e em amostras autoclavada. Foram comparados, ainda, diferentes métodos de extração, usando um kit comercial e a técnica clássica, utilizando fenol/clorofórmio. O resultado estatístico foi obtido por tabela de contingência, analisada pelo teste do qui-quadrado (χ2) e do exato de Fisher. A especificidade encontrada foi altamente significativa (P<0,0001). Observou-se também sensibilidade altamente significativa nas diluições a partir de 10% (P<0,0001). A técnica tem alta especificidade e sensibilidade para detectar até mesmo contaminação de 1%, mas a repetibilidade desse resultado impede a aplicação oficial desse método para a inspeção de contaminação acidental, sendo recomendada somente para inspeção de fraude a partir de 10% de substituição. Em carnes autoclavadas, a eficácia do teste é menor. A técnica pode ser empregada para certificação de produto específico (selo de identidade de espécie).

The present study aimed at evaluate the viability of PCR-RFLP (Polymerase Chain Reaction - Restriction Fragment Length Polymorphism) for identification of fraud and/or accidental contamination in buffalo meat - fresh and processed. Pure, autoclaved and controlled fraud samples, produced in the laboratory with the addition of 1, 5, 10 and 50% of beef in raw homogenized buffalo meat samples, were tested. Furthermore, different extraction methods, using a commercial kit and classical technique using phenol-chloroform, were compared. The statistical result was obtained by contingency table analyzed by chi-square and the Fisher exact test. The specificity was highly significant (p <0.0001), and the sensitivity was highly significant in dilutions from 10% (p <0.0001). Despite its accuracy and precision, capable to detect a contamination level of 1%, PCR-RFLP technique is not recommended for inspection in cases of accidental contamination. This is due to the need of test repetition in levels of contamination lower than 10%. The efficiency of this test is lower to autoclaved meat. The PCR-RFPL technique can be used for certification of food made with specific species (species identification certification stamp).

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Low-level laser therapy treatment (LLLT) is widely used in rehabilitation clinics with the aim of accelerating the process of tissue repair; however, the molecular bases of the effect of LLLT have not been fully established. The aim of the present study was to evaluate the influence of the exposure of different doses of LLLT on the expression of collagen genes type I alpha 1 (COL1α1) and vascular endothelial growth factor (VEGF) in the fibroblast cells of mice (L929) cultivated in vitro. Fibroblast cells were irradiated with a Gallium-Arsenide laser (904 nm) every 24 h for 2 consecutive days, stored in an oven at 37 °C, with 5% CO2 and divided into 3 groups: G1-control group, G2-irradiated at 2 J/cm(2), and G3-irradiated at 3 J/cm(2). After irradiation, the total RNA was extracted and used in the complementary DNA (cDNA) synthesis. The gene expression was analyzed by real-time polymerase chain reaction. The cells irradiated in G2 exhibited a statistically significant growth of 1.78 in the expression of the messenger RNA (mRNA) of the COL1α1 gene (p = 0.036) in comparison with G1 and G3. As for the VEGF gene, an increase in expression was observed in the two irradiated groups in comparison with the control group. There was an increase in expression in G2 of 2.054 and G3 of 2.562 (p = 0.037) for this gene. LLLT (904 nm) had an influence on the expression of the genes COL1α1 (2 J/cm(2)) and VEGF (2 e 3 J/cm(2)) in a culture of the fibroblast cells of mice.

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The aim of the present study was to characterize the relationships that occur between morphometric variables of larvae of Lophiosilurus alexandri Steindachner, 1876 through their allometric growth analysis. Total length, head length and body height were correlated with standard length, head height and body height, as well as eye diameter and head height with head length. The results revealed allometric positive relation during the initial development, where the b coefficient varied between 1.10 and 2.81. The variable pre-anal distance in relation to the standard length and the snout length in relation to the head length revealed an allometric negative relation, where the b coefficient was 0.85 and 0.94, respectively.(AU)

O objetivo do presente estudo foi caracterizar os tipos de relações que ocorrem entre as variáveis morfométricas das larvas de Lophiosilurus alexandri Steindachner, 1876, por meio da análise de seu crescimento alométrico. As variáveis comprimento total, comprimento da cabeça e altura do corpo foram correlacionadas com o comprimento padrão; a altura da cabeça com a altura do corpo; e o diâmetro do olho e a altura da cabeça com o comprimento da cabeça. Os resultados revelaram relações alométricas positivas durante o desenvolvimento inicial, quando o coeficiente b variou entre 1,10 e 2,81. A variável distância pré-anal em relação ao comprimento padrão e a variável comprimento do focinho em relação ao comprimento da cabeça revelaram relação alométrica negativa quando o coeficiente b foi 0,85 e 0,94, respectivamente.(AU)

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The aim of the present study was to characterize the relationships that occur between morphometric variables of larvae of Lophiosilurus alexandri Steindachner, 1876 through their allometric growth analysis. Total length, head length and body height were correlated with standard length, head height and body height, as well as eye diameter and head height with head length. The results revealed allometric positive relation during the initial development, where the b coefficient varied between 1.10 and 2.81. The variable pre-anal distance in relation to the standard length and the snout length in relation to the head length revealed an allometric negative relation, where the b coefficient was 0.85 and 0.94, respectively.

O objetivo do presente estudo foi caracterizar os tipos de relações que ocorrem entre as variáveis morfométricas das larvas de Lophiosilurus alexandri Steindachner, 1876, por meio da análise de seu crescimento alométrico. As variáveis comprimento total, comprimento da cabeça e altura do corpo foram correlacionadas com o comprimento padrão; a altura da cabeça com a altura do corpo; e o diâmetro do olho e a altura da cabeça com o comprimento da cabeça. Os resultados revelaram relações alométricas positivas durante o desenvolvimento inicial, quando o coeficiente b variou entre 1,10 e 2,81. A variável distância pré-anal em relação ao comprimento padrão e a variável comprimento do focinho em relação ao comprimento da cabeça revelaram relação alométrica negativa quando o coeficiente b foi 0,85 e 0,94, respectivamente.

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The Brazilian cattle population is mainly composed of breeds of zebuine origin and their American derivatives. Comprehensive knowledge about the genetic diversity of these populations is fundamental for animal breeding programs and the conservation of genetic resources. This study aimed to assess the phylogenetic relationships, levels of genetic diversity, and patterns of taurine/zebuine admixture among 9 commercial cattle breeds raised in Brazil. Analysis of DNA polymorphisms was performed on 2965 animals using the 11 microsatellite markers recommended by the International Society of Animal Genetics. High genetic diversity was detected in all breeds, even though significant inbreeding was observed within some. Differences among the breeds accounted for 14.72% of the total genetic variability, and genetic differentiation was higher among taurine than among zebuine cattle. Of note, Nelore cattle presented with high levels of admixture, which is consistent with the history of frequent gene flow during the establishment of this breed in Brazil. Furthermore, significant genetic variability was partitioned within the commercial cattle breeds formed in America, which, therefore, comprise important resources of genetic diversity in the tropics. The genetic characterization of these important Brazilian breeds may now facilitate the development of management and breeding programs for these populations.

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Only a few studies have described hormonal treatments for induction of synchronicity and gamete collection in Nile tilapia (Oreochromis niloticus), both important for assortative matings in breeding programmes and essential for polyploidy technologies. In this study, we compared the effectiveness of carp pituitary extract (CPE), Nile tilapia pituitary extract (TPE), human chorionic gonadotropin (hCG) and gonadotropin-releasing hormone (GnRH) protocols on the induction of spawning and egg production in Nile tilapia. Among the hormonal treatments analysed, only hCG was effective for producing viable gametes for in vitro fertilization. To verify the viability of this hormonal treatment, hCG was tested using different doses (1000, 2000, 3000, 4000 and 5000 IU/kg) in a large number of females (208 animals) from two Nile tilapia lines. The results indicated that hCG doses between 1000 and 5000 IU/kg could be used to induce final oocyte maturation in Nile tilapia with collection of stripped oocytes. This is the first study to report differential reproductive responses to hormonal treatment between tilapia lines: line 1 was more efficient at producing eggs and post-hatching larvae after hCG induction than line 2. In conclusion, we demonstrated that the hCG protocol may be applied on a large scale to induce final oocyte maturation in Nile tilapia. The development of a protocol for in vitro fertilization in Nile tilapia may aid in breeding programmes and biotechnological assays for the development of genetically modified lines of Nile tilapia.

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Foram testados três métodos de extração de DNA em amostras de queijo, com o objetivo de identificar uma técnica eficiente para extração de DNA em amostras com várias limitações, como alto teor de gordura, alto grau de degradação do DNA e grande concentração de impurezas. A técnica que faz uso do tiocianato de guanidina mostrou-se mais adequada para identificação de adição intencional não declarada de leite bovino em queijos bubalinos, podendo ser empregada para certificação de produto específico (selo de Identidade de Espécie).

Three methods of DNA extraction were tested in cheese samples. The objective of this study was to identify an efficient technique for DNA extraction in different samples with several limitations, such as high fat tenor, high degree of DNA degradation and great sludge concentration. The technique using Guanidine thiocyanate was more appropriate for identification of intentional undeclared addition of bovine milk in buffalo cheeses. This technique can be used for certification of a specific product (stamp of Identity of Species).

RESUMEN

Foram testados três métodos de extração de DNA em amostras de queijo, com o objetivo de identificar uma técnica eficiente para extração de DNA em amostras com várias limitações, como alto teor de gordura, alto grau de degradação do DNA e grande concentração de impurezas. A técnica que faz uso do tiocianato de guanidina mostrou-se mais adequada para identificação de adição intencional não declarada de leite bovino em queijos bubalinos, podendo ser empregada para certificação de produto específico (selo de Identidade de Espécie).(AU)

Three methods of DNA extraction were tested in cheese samples. The objective of this study was to identify an efficient technique for DNA extraction in different samples with several limitations, such as high fat tenor, high degree of DNA degradation and great sludge concentration. The technique using Guanidine thiocyanate was more appropriate for identification of intentional undeclared addition of bovine milk in buffalo cheeses. This technique can be used for certification of a specific product (stamp of Identity of Species).(AU)

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O presente estudo avaliou a PCR como técnica para sexagem molecular em aves, a qual empregou os primers P2/P8, relacionados com os cromossomos sexuais (Z/W) das aves. Os produtos da PCR foram submetidos à corrida eletroforética, e esta revelou que o tamanho dos pares de base (pb) variou entre as espécies: de 246 a 396 pb para o alelo Z e de 254 a 412 pb para o W. Os resultados mostraram 76 machos (49,31%) e 78 fêmeas (50,69%), totalizando 154 aves. Esta situação propõe desvios meramente casuais ao teste χ² (P > 0,05), pois sendo a variável estudada dicotômica, a relação 1:1 está dentro de um universo amostral. Tais dados mostram que esta técnica, utilizando DNA extraído tanto de penas quanto de sangue, é segura e eficaz para a determinação sexual das aves.

This study evaluated PCR as a technique for molecular sexing in birds using the primers P2/P8, related to the sex chromosomes (Z/W) of birds. The PCR products under electrophoresis showing the size of the base pairs (bp) varying between species: 246 to 396 bp for the allele Z and 254 to 412 for W. The results identified 76 males (49,31%) and 78 females (50,69%), totalizing 154 birds. This situation proposes casual deviations, Test χ² (p>0.05), as being the dicotomic variable studied the 1:1 ratio is within a sampling universe. The data show that the technique is accurate and effective for sex determination of birds, both using DNA extracted from feathers and blood.

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O presente estudo avaliou a PCR como técnica para sexagem molecular em aves, a qual empregou os primers P2/P8, relacionados com os cromossomos sexuais (Z/W) das aves. Os produtos da PCR foram submetidos à corrida eletroforética, e esta revelou que o tamanho dos pares de base (pb) variou entre as espécies: de 246 a 396 pb para o alelo Z e de 254 a 412 pb para o W. Os resultados mostraram 76 machos (49,31%) e 78 fêmeas (50,69%), totalizando 154 aves. Esta situação propõe desvios meramente casuais ao teste χ² (P > 0,05), pois sendo a variável estudada dicotômica, a relação 1:1 está dentro de um universo amostral. Tais dados mostram que esta técnica, utilizando DNA extraído tanto de penas quanto de sangue, é segura e eficaz para a determinação sexual das aves.(AU)

This study evaluated PCR as a technique for molecular sexing in birds using the primers P2/P8, related to the sex chromosomes (Z/W) of birds. The PCR products under electrophoresis showing the size of the base pairs (bp) varying between species: 246 to 396 bp for the allele Z and 254 to 412 for W. The results identified 76 males (49,31%) and 78 females (50,69%), totalizing 154 birds. This situation proposes casual deviations, Test χ² (p>0.05), as being the dicotomic variable studied the 1:1 ratio is within a sampling universe. The data show that the technique is accurate and effective for sex determination of birds, both using DNA extracted from feathers and blood. (AU)

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Foram utilizados 159 cavalos Pampa, registrados na Associação Brasileira dos Criadores de Cavalo Pampa, e um grupo-controle, de 32 cavalos da raça Paint, ambos os grupos provenientes de plantéis de diferentes regiões brasileiras, com o objetivo de comparar os testes bioquímico e molecular para detecção de marcadores genéticos para pelagem tobiana em cavalos Pampa. Houve diferença significativa (P<0,001) entre os testes bioquímico e molecular, nos cavalos Pampa, mas o mesmo fato não ocorreu com os da raça Paint. Os resultados mostraram que o marcador molecular (KIT) foi mais eficiente na identificação dos prováveis cavalos homozigotos do que os marcadores bioquímicos albumina (Al) e proteína de ligação da vitamina D (Gc), em ambas as raças.

In this study, 159 Pampa horses, registered at the Associação Brasileira dos Criadores de Cavalo Pampa, and a control group of 32 Paint horses, both coming from herds located in different Brazilian regions, were used to compare biochemical and molecular tests for detection of genetic markers for the Tobiano coat color pattern in Pampa horses. Difference (P<0.001) between biochemical and molecular tess in Pampa horses was observed, but not for the Paint horses. The results showed that the molecular marker (KIT) was more efficient to identify the probable homozygous dominant horses than the biochemical markers albumin (Al) and vitamin D-binding Protein (Gc), in both breeds.

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Foram utilizados 159 cavalos Pampa, registrados na Associação Brasileira dos Criadores de Cavalo Pampa, e um grupo-controle, de 32 cavalos da raça Paint, ambos os grupos provenientes de plantéis de diferentes regiões brasileiras, com o objetivo de comparar os testes bioquímico e molecular para detecção de marcadores genéticos para pelagem tobiana em cavalos Pampa. Houve diferença significativa (P<0,001) entre os testes bioquímico e molecular, nos cavalos Pampa, mas o mesmo fato não ocorreu com os da raça Paint. Os resultados mostraram que o marcador molecular (KIT) foi mais eficiente na identificação dos prováveis cavalos homozigotos do que os marcadores bioquímicos albumina (Al) e proteína de ligação da vitamina D (Gc), em ambas as raças.(AU)

In this study, 159 Pampa horses, registered at the Associação Brasileira dos Criadores de Cavalo Pampa, and a control group of 32 Paint horses, both coming from herds located in different Brazilian regions, were used to compare biochemical and molecular tests for detection of genetic markers for the Tobiano coat color pattern in Pampa horses. Difference (P<0.001) between biochemical and molecular tess in Pampa horses was observed, but not for the Paint horses. The results showed that the molecular marker (KIT) was more efficient to identify the probable homozygous dominant horses than the biochemical markers albumin (Al) and vitamin D-binding Protein (Gc), in both breeds.(AU)

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SUMMARY: The aim of the present study was to determine the action of AsGA laser irradiation on bone repair in the tibia of osteopenic rats. The animals were randomly divided into eight experimental groups according to the presence of ovarian hormone (sham group) or the absence of the hormone (OVX group), as well as being irradiated or non-irradiated. Low-level 904-nm laser (50 mJ/cm(2)) accelerated the repair process of osteopenic fractures, especially in the initial phase of bone regeneration. INTRODUCTION: The development of new techniques to speed the process of bone repair has provided significant advances in the treatment of fractures. Some attention recently focused on the effects of biostimulation on bone. METHODS: Forty-eight adult rats were randomly divided into eight experimental groups (six animals in each group) according to the presence of ovarian hormone (sham group) or absence of the hormone (ovariectomized (OVX) group) as well as being irradiated or non-irradiated. For the application of low-level laser therapy, the animals were anesthetized with one third of the dose sufficient to immobilize the animal and irradiated with AsGa laser (904 nm, 50 mJ/cm(2) for 2 s, point form and in contact). The control animals received the same type of manipulation as the irradiated animals, but with the laser turned off. Half of the animals were killed 7 days following the confection of the bone defect, and the other half were killed 21 days after the surgery. After complete demineralization, the tibias were cut cross-sectionally in the central region of the bone defect and embedded in paraffin blocks. The blocks were then cut in semi-seriated slices and stained with hematoxylin and eosin. RESULTS: There was new bone formation in the animals in the OVX group with laser treatment killed after 7 days (p < 0.001). The lowest percentage of bone formation was observed in the OVX without laser killed after 7 days (p > 0.05). All animals killed after 21 days exhibited linear closure of the lesion. CONCLUSION: Low-level 904-nm laser (50 mJ/cm(2)) accelerated the repair process of osteopenic fractures, especially in the initial phase of bone regeneration.

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O cultivo de populações monossexo ou estéreis de tilápia é necessário, uma vez que a reprodução destes animais durante o cultivo provoca gastos energéticos e menor desempenho somático. A sexagem manual e a produção de progênie 100% macho a partir do acasalamento entre Oreochromis niloticus e O. hornorum são técnicas difíceis. A produção de progênie monossexo macho, filhos de supermachos YY, apresenta-se como técnica de manipulação sexual promissora. Porém, a inversão sexual com o uso de hormônios para a formação de população monossexo ainda é o método mais utilizado. A formação de lotes estéreis triploides por meio de manipulações cromossômicas também é uma opção a ser desenvolvida.

The culture of monosex or sterile Nile tilapia is necessary. The allocation of energy to reproduction during its culture leads to performance reduction. The hand sorting and monosex progeny produced by interspecific hybridization (Oreochromis niloticus and O. hornorum cross) are difficult methods. The production of all male progeny from YY supermales shows good promise technique. However, sex-reversal by hormone treatment is the best option yet. A sterile triploid stock through chromosome set manipulation is also an alternative to be developed.

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Peso corporal é o principal objetivo de seleção, e a seleção massal é o principal método em programas de melhoramento genético de tilápias do Nilo. O rendimento de filé é característica importante, mas há a necessidade do uso de informações de parentes para a predição de valores genéticos ou do uso de características correlacionadas, como medidas morfométricas, para garantir ganhos genéticos indiretos. Há pouca informação na literatura sobre estimativas de componentes de (co) variância genética de rendimentos de filé e medidas corporais para a espécie. A herdabilidade baixa do rendimento de filé, as herdabilidades moderadas a altas das medidas morfométricas e as altas correlações genéticas entre elas favoreceriam a seleção indireta.

Body weight is the breeding goal in genetic improvement programs for Nile tilapia and mass selection is the most used method. Fillet yield is an important trait for chain production of this fish. For breeding value prediction for this trait, pedigree information or correlated traits are necessary to guarantee indirect genetic gains. There is poor information in literature about estimated genetic (co)variance components for fillet traits and morfometric measurements in Nile tilapia. The low heritability of the fillet percentage, medium to high heritabilities for morfometric measurements and the high genetic correlations among them could collaborate for indirect selection.

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Peso corporal é o principal objetivo de seleção, e a seleção massal é o principal método em programas de melhoramento genético de tilápias do Nilo. O rendimento de filé é característica importante, mas há a necessidade do uso de informações de parentes para a predição de valores genéticos ou do uso de características correlacionadas, como medidas morfométricas, para garantir ganhos genéticos indiretos. Há pouca informação na literatura sobre estimativas de componentes de (co) variância genética de rendimentos de filé e medidas corporais para a espécie. A herdabilidade baixa do rendimento de filé, as herdabilidades moderadas a altas das medidas morfométricas e as altas correlações genéticas entre elas favoreceriam a seleção indireta.(AU)

Body weight is the breeding goal in genetic improvement programs for Nile tilapia and mass selection is the most used method. Fillet yield is an important trait for chain production of this fish. For breeding value prediction for this trait, pedigree information or correlated traits are necessary to guarantee indirect genetic gains. There is poor information in literature about estimated genetic (co)variance components for fillet traits and morfometric measurements in Nile tilapia. The low heritability of the fillet percentage, medium to high heritabilities for morfometric measurements and the high genetic correlations among them could collaborate for indirect selection.(AU)

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O cultivo de populações monossexo ou estéreis de tilápia é necessário, uma vez que a reprodução destes animais durante o cultivo provoca gastos energéticos e menor desempenho somático. A sexagem manual e a produção de progênie 100% macho a partir do acasalamento entre Oreochromis niloticus e O. hornorum são técnicas difíceis. A produção de progênie monossexo macho, filhos de supermachos YY, apresenta-se como técnica de manipulação sexual promissora. Porém, a inversão sexual com o uso de hormônios para a formação de população monossexo ainda é o método mais utilizado. A formação de lotes estéreis triploides por meio de manipulações cromossômicas também é uma opção a ser desenvolvida. (AU)

The culture of monosex or sterile Nile tilapia is necessary. The allocation of energy to reproduction during its culture leads to performance reduction. The hand sorting and monosex progeny produced by interspecific hybridization (Oreochromis niloticus and O. hornorum cross) are difficult methods. The production of all male progeny from YY supermales shows good promise technique. However, sex-reversal by hormone treatment is the best option yet. A sterile triploid stock through chromosome set manipulation is also an alternative to be developed.(AU)

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