Genetic diversity in Amazonian Jundiá (Leiarius marmoratus) stocks using heterologous primers

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)

Genetic diversity in Amazonian Jundiá (Leiarius marmoratus) stocks using heterologous primers / Genetic diversity in Amazonian Jundiá (Leiarius marmoratus) stocks using heterologous primers

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.

Genetic diversity in Amazonian Jundiá (Leiarius marmoratus) stocks using he erologous primers

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)

Genetic diversity in Amazonian Jundiá (Leiarius marmoratus) stocks using heterologous primers / Genetic diversity in Amazonian Jundiá (Leiarius marmoratus) stocks using heterologous primers

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.

Expression of the PEPT1, CAT, SOD2 and GPX1 genes in the zebrafish intestine supplemented with methionine dipeptide under predation risk.

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.

Produção de pós-larvas de tilápia do Nilo em sistemade recirculação de água com tanques retangulares e diferentes designs de entrada de água / Nile tilapia post-larvae production in a recirculating aquaculture system with rectangular tanks and different water inlet designs

O objetivo do presente estudo foi avaliar o efeito de diferentes formas de entrada de água em tanques retangulares na produção de pós-larvas de tilápia do Nilo em sistema de recirculação. 720 animais com peso de 0,02 g e comprimento de 12.52 mm foram distribuídos em 12 tanques retangulares, com relação de comprimento/largura de 1,20 e vazão de entrada de água de 3,2 vezes o volume útil dos tanques. Os tratamentos consistiram em três designs de entrada de água: superior, única vertical submersa e dupla vertical submersa, com quatro repetições cada. Foram avaliados o desempenho produtivo (peso e comprimento final, taxa de crescimento específico, fator de condição e sobrevivência) e a qualidade de água (pH, oxigênio dissolvido, temperatura, sólidos dissolvidose condutividade elétrica). O oxigênio dissolvido foi avaliado nas quatro extremidades e ao centro de cada tanque para verificar a existência de zonas mortas. Além disso, foi verificado a concentração de sólidos suspensos, 30 minutos após o arraçoamento aos 21 dias de estudo. O design de entrada de água não influenciou no desempenho produtivo e nos parâmetros gerais de qualidade de água (p>0,05). Não houve diferença na concentração de oxigênio dissolvido dentro do tanque do mesmo tratamento, indicando que não houve formação de zonas mortas (p>0,05). Houve diferença na concentração de oxigênio dissolvido nas extremidades e no centro dos tanques, devido aos tratamentos, onde os menores valores foram verificados para os tanques com entrada de água única vertical submersa (p<0,05). Os tanques com dupla entrada vertical submersa apresentaram menor concentração de sólidos suspensos, em comparação aos demais tratamentos (p<0,05). Dessa forma, não é indicado a utilização de entrada única vertical submersa e como nãohouve influência negativa no desempenho produtivo e qualidade de água, é possível produzir pós-larvas de tilápia do Nilo com entrada de água superior.

The aim of the present study was to evaluate the effect of the water inlet design in rectangular tanks, on the water quality and productive performance of Nile tilapia post-larvae. 720 animals weighing 0.02 g and 12.52 mm in length were distributed in 12 rectangular tanks, with a length/width ratio of 1.20 and a water inlet flow of 3.2 times the useful volume of the tanks. The treatments consisted of three water inlet designs: upper, single vertical submerged, and double vertical submerged, distributed in four replicates each. Productive performance (weight and final length, specific growth rate, condition factor and survival) and water quality (pH, dissolved oxygen, temperature, dissolved solids and electrical conductivity) parameter were evaluated. Dissolved oxygen was evaluated at the four ends and center of each tank to check for dead zones. In addition, the suspended solids concentration was evaluated 30 minutes after feeding at 21 days of study. The water inlet design did not influence theproductive performance and the general parameter of water quality (p>0.05). There was no difference in the concentration of dissolved oxygen within the tank for each treatment, which indicates that there was no formation of dead zones (p>0.05). There wasa difference in the concentration of dissolved oxygen in the extremities and the center of the tanks due to the treatments, where the lowest values were verifies for the tanks with submerged vertical water inlet (p<0.05). The tanks with submerged verticaldouble inlets showed a lower concentration of suspended solids, compared to the other treatments (p<0.05). Thus, the use of a single vertical submerged inlet is not indicated and there was no negative influence on production performance and water quality,it is possible to produce Nile tilapia post-larvae with upper water inlet.

Produção de pós-larvas de tilápia do Nilo em sistemade recirculação de água com tanques retangulares e diferentes designs de entrada de água / Nile tilapia post-larvae production in a recirculating aquaculture system with rectangular tanks and different water inlet designs

O objetivo do presente estudo foi avaliar o efeito de diferentes formas de entrada de água em tanques retangulares na produção de pós-larvas de tilápia do Nilo em sistema de recirculação. 720 animais com peso de 0,02 g e comprimento de 12.52 mm foram distribuídos em 12 tanques retangulares, com relação de comprimento/largura de 1,20 e vazão de entrada de água de 3,2 vezes o volume útil dos tanques. Os tratamentos consistiram em três designs de entrada de água: superior, única vertical submersa e dupla vertical submersa, com quatro repetições cada. Foram avaliados o desempenho produtivo (peso e comprimento final, taxa de crescimento específico, fator de condição e sobrevivência) e a qualidade de água (pH, oxigênio dissolvido, temperatura, sólidos dissolvidose condutividade elétrica). O oxigênio dissolvido foi avaliado nas quatro extremidades e ao centro de cada tanque para verificar a existência de zonas mortas. Além disso, foi verificado a concentração de sólidos suspensos, 30 minutos após o arraçoamento aos 21 dias de estudo. O design de entrada de água não influenciou no desempenho produtivo e nos parâmetros gerais de qualidade de água (p>0,05). Não houve diferença na concentração de oxigênio dissolvido dentro do tanque do mesmo tratamento, indicando que não houve formação de zonas mortas (p>0,05). Houve diferença na concentração de oxigênio dissolvido nas extremidades e no centro dos tanques, devido aos tratamentos, onde os menores valores foram verificados para os tanques com entrada de água única vertical submersa (p<0,05). Os tanques com dupla entrada vertical submersa apresentaram menor concentração de sólidos suspensos, em comparação aos demais tratamentos (p<0,05). Dessa forma, não é indicado a utilização de entrada única vertical submersa e como nãohouve influência negativa no desempenho produtivo e qualidade de água, é possível produzir pós-larvas de tilápia do Nilo com entrada de água superior.(AU)

The aim of the present study was to evaluate the effect of the water inlet design in rectangular tanks, on the water quality and productive performance of Nile tilapia post-larvae. 720 animals weighing 0.02 g and 12.52 mm in length were distributed in 12 rectangular tanks, with a length/width ratio of 1.20 and a water inlet flow of 3.2 times the useful volume of the tanks. The treatments consisted of three water inlet designs: upper, single vertical submerged, and double vertical submerged, distributed in four replicates each. Productive performance (weight and final length, specific growth rate, condition factor and survival) and water quality (pH, dissolved oxygen, temperature, dissolved solids and electrical conductivity) parameter were evaluated. Dissolved oxygen was evaluated at the four ends and center of each tank to check for dead zones. In addition, the suspended solids concentration was evaluated 30 minutes after feeding at 21 days of study. The water inlet design did not influence theproductive performance and the general parameter of water quality (p>0.05). There was no difference in the concentration of dissolved oxygen within the tank for each treatment, which indicates that there was no formation of dead zones (p>0.05). There wasa difference in the concentration of dissolved oxygen in the extremities and the center of the tanks due to the treatments, where the lowest values were verifies for the tanks with submerged vertical water inlet (p<0.05). The tanks with submerged verticaldouble inlets showed a lower concentration of suspended solids, compared to the other treatments (p<0.05). Thus, the use of a single vertical submerged inlet is not indicated and there was no negative influence on production performance and water quality,it is possible to produce Nile tilapia post-larvae with upper water inlet.(AU)

Effects of genotype × environment interaction on the estimation of genetic parameters and gains in Nile tilapia.

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.

Zebrafish breeding program: genetic parameters estimates for growth traits.

The objective of this study was to evaluate the genetic parameters of two generations of zebrafish breeding program. The base population was formed by crossing individuals of six commercial stocks of zebrafish, resulting in a nucleus with 60 families. Two generations were evaluated, with a total of 780 and 781 individuals for the first and second generation, respectively. The selection was made based on the mean genetic value of each family, followed by mass selection of the breeders. Mathematical models that considered the fixed (age, density in the larval stage, sex, and generation) and random (animal additive genetics, common to full-sibs, and residual) effects were evaluated using BLUPF90 program family. Weight and total length were used as response variables. Total length was the best selection criterion because it had a higher heritability (0.30) than weight (0.22). There was a high common to full-sib effect, especially in the first generation of animals. For second-generation data, the heritability was 0.26 for total length, as well as a lower common to full-sib effect for length. The best model obtained for this evaluation was considering all effects, being age and density as first and second polynomial, respectively. The genetic and phenotypic correlations for weight and length were 0.87 and 0.75, respectively. These results indicate that genetic breeding using total length as the selection criterion may produce a larger and heavier zebrafish strain.

Glúten de trigo em dietas para tilápia do Nilo: digestibilidade e desempenho produtivo de larvas / Wheat gluten in the diet of Nile tilapia:digestibility and larvae growth performance

O objetivo do presente trabalho foi avaliar o potencial de utilização do glúten de trigo em dietas para tilápia-do-nilo (Orechromisniloticus), através de estudos de digestibilidade e desempenho produtivo de larvas. Para o estudo de digestibilidade foi elaboradauma dieta referência e uma dieta teste, contendo glúten de trigo. Utilizou-se o óxido de crômio III como marcador inerte. As fezescoletadas foram destinadas à análise de composição química, assim como as rações e o ingrediente teste. Além disso, foi realizadaanálise de leitura de óxido de crômio das fezes e das dietas. Os resultados obtidos por meio dessas análises foram utilizadospara calcular os coeficientes de digestibilidade. Com base nesses coeficientes foram elaboradas as dietas experimentais dosestudos de dose-resposta para larvas. Foram formuladas cinco dietas experimentais com diferentes níveis de inclusão de glútende trigo, sendo de 0%; 2,5%; 5,0%, 7,5% e 10%. Ao final do experimento foram avaliados o desempenho produtivo dos animais.Os dados de desempenho foram submetidos à análise de regressão linear a 5% de probabilidade. O glúten de trigo apresentaelevados coeficientes de digestibilidade para matéria seca, proteína bruta e energia bruta, sendo de 94,02; 98,18 e 96,90%,respectivamente. A análise de regressão demonstrou um efeito linear negativo quanto ao comprimento final e sobrevivência daslarvas conforme aumentou-se o nível desse alimento. Dessa forma, conclui-se que o glúten de trigo é um ingrediente potencialpara ser utilizado em dietas para tilápia-do-nilo, não sendo recomendada sua inclusão na fase larval.(AU)

The objective of this study was to evaluate the utilization potential of wheat gluten in diets for Nile tilapia (Oreochromis niloticus)through studies of digestibility and productive performance of larvae. For the digestibility study was elaborated a reference dietand a test diet containing wheat gluten. Chromium oxide-III was used as an inert marker. The collected faeces were destined toanalysis of chemists compounds as the feed, and the test ingredient. Besides, reading chromium oxide analysis was performed in thefaeces and diets. The results obtained through these analyses were used to calculate the digestibility coefficients. Based on thesecoefficients, experimental diets were elaborated for the dose-response studies in larvae. For the experiment, five experimental dietswere formulated with different inclusion levels of wheat gluten, with 0%; 2,5%; 5,0%, 7,5% and 10%. At the end of the experiment,the productive performance was evaluated. The performance data were submitted to linear regression with 5% of probability. Thewheat gluten presents high digestibility coefficients for dry matter, crude protein and gross energy with 94,02; 98.18 and 96.90%,respectively. The regression analyses showed a negative linear effect on the final length and survival of the larvae when the levelof this food was increased. Thus, it is concluded that wheat gluten is a potential ingredient to be utilized in diets for Nile tilapia, notbeing recommended its inclusion in the larvae period.(AU)

Glúten de trigo em dietas para tilápia do Nilo: digestibilidade e desempenho produtivo de larvas / Wheat gluten in the diet of Nile tilapia: digestibility and larvae growth performance

O objetivo do presente trabalho foi avaliar o potencial de utilização do glúten de trigo em dietas para tilápia-do-nilo (Orechromis niloticus), através de estudos de digestibilidade e desempenho produtivo de larvas. Para o estudo de digestibilidade foi elaborada uma dieta referência e uma dieta teste, contendo glúten de trigo. Utilizou-se o óxido de crômio III como marcador inerte. As fezes coletadas foram destinadas à análise de composição química, assim como as rações e o ingrediente teste. Além disso, foi realizada análise de leitura de óxido de crômio das fezes e das dietas. Os resultados obtidos por meio dessas análises foram utilizados para calcular os coeficientes de digestibilidade. Com base nesses coeficientes foram elaboradas as dietas experimentais dos estudos de dose-resposta para larvas. Foram formuladas cinco dietas experimentais com diferentes níveis de inclusão de glúten de trigo, sendo de 0%; 2,5%; 5,0%, 7,5% e 10%. Ao final do experimento foram avaliados o desempenho produtivo dos animais. Os dados de desempenho foram submetidos à análise de regressão linear a 5% de probabilidade. O glúten de trigo apresenta elevados coeficientes de digestibilidade para matéria seca, proteína bruta e energia bruta, sendo de 94,02; 98,18 e 96,90%, respectivamente. A análise de regressão demonstrou um efeito linear negativo quanto ao comprimento final e sobrevivência das larvas conforme aumentou-se o nível desse alimento. Dessa forma, conclui-se que o glúten de trigo é um ingrediente potencial para ser utilizado em dietas para tilápia-do-nilo, não sendo recomendada sua inclusão na fase larval.

The objective of this study was to evaluate the utilization potential of wheat gluten in diets for Nile tilapia (Oreochromis niloticus) through studies of digestibility and productive performance of larvae. For the digestibility study was elaborated a reference diet and a test diet containing wheat gluten. Chromium oxide-III was used as an inert marker. The collected faeces were destined to analysis of chemists compounds as the feed, and the test ingredient. Besides, reading chromium oxide analysis was performed in the faeces and diets. The results obtained through these analyses were used to calculate the digestibility coefficients. Based on these coefficients, experimental diets were elaborated for the dose-response studies in larvae. For the experiment, five experimental diets were formulated with different inclusion levels of wheat gluten, with 0%; 2,5%; 5,0%, 7,5% and 10%. At the end of the experiment, the productive performance was evaluated. The performance data were submitted to linear regression with 5% of probability. The wheat gluten presents high digestibility coefficients for dry matter, crude protein and gross energy with 94,02; 98.18 and 96.90%, respectively. The regression analyses showed a negative linear effect on the final length and survival of the larvae when the level of this food was increased. Thus, it is concluded that wheat gluten is a potential ingredient to be utilized in diets for Nile tilapia, not being recommended its inclusion in the larvae period.

Effect of different periods of pre-slaughter stress on the quality of the Nile tilapia meat

Abstract The study was carried out with the objective of evaluating the influence of pre-slaughter stress on meat quality of Nile tilapia (O. niloticus) for 10 days of storage in ice. 75 whole fish were used eviscerated, with average weight and length of 825.75 ± 101.59 g and 28.25 ± 0.81 cm, respectively. The treatments consisted of time in which the animals underwent pre-slaughter hypoxia, being 0, 3 and 6 minutes. Rigor mortis and muscle pH were assessed besides the application of the Quality Index Method and analysis of total protein and blood glucose. Rigor mortis did not differ among treatments during the storage period, and after three hours all animals were in rigor stage. The muscle pH values varied widely during the study period, observing higher values on the third day of storage. Sensory analysis showed that after 10 days the tilapia from the different treatments did not differ in the evaluated quality parameters similarly, there was no difference regarding the evaluated blood biochemical parameters Thus, hypoxia of 6 minutes pre-slaughter does not influence the rigor mortis, muscle pH, qualitative perception of the meat quality, total protein and blood glucose of Nile tilapia.

Tilapia by-product hydrolysate powder in diets for Nile tilapia larvae / Hidrolisado proteico seco do resíduo da filetagem de tilápias em dietas para larvas de tilápia do Nilo

This study aimed to evaluate the digestibility of tilapia by-product protein hydrolysate powder (TBHP) from tilapia filleting by-product, and its inclusion in diets for Nile tilapia larvae. In order to determine the apparent digestibility coefficients, two diets were formulated, the reference diet and the test diet (20% of TBHP) and, to evaluate the inclusion, six diets were formulated, which were with 0.0, 2.0; 4.0; 6.0, and 8.0% of TBHP. The apparent digestibility coefficients of crude protein and gross energy were 89.5 and 98.3%, respectively. At levels above 4.0% of inclusion of TBHP, the weight, final length and weight gain were impaired, however, survival rate was higher (p 0.05). The TBHP can be used in diets for tilapia due to the high digestibility coefficients for crude protein and gross energy. The inclusion of up to 4.0% of TBHP does not affect the reproductive performance and survival rate of Nile tilapia larvae.

Objetivou-se avaliar a digestibilidade do hidrolisado proteico seco do resíduo da filetagem de tilápias (HPST) e sua inclusão em dietas para larvas de tilápia do Nilo. Para determinar os coeficientes de digestibilidade aparente, duas dietas foram elaboradas, referência e teste (com 20% do HPST) e para avaliação da inclusão, seis dietas foram formuladas com 0,0, 2,0; 4,0; 6,0, e 8,0% de HPST. Os coeficientes de digestibilidade aparente da proteína e energia bruta foram de 89,5 e 98,3%, respectivamente. Nos níveis acima de 4,0% de inclusão de HPST o peso e comprimento final e ganho em peso foram prejudicados, no entanto a sobrevivência foi maior (p 0,05). O HPST pode ser utilizado em dietas para tilápias em função dos elevados coeficientes de digestibilidade para proteína bruta e energia bruta. A inclusão de até 4,0% de HPST não afeta o desempenho produtivo e a sobrevivência de larvas de tilápias do Nilo.

Tilapia by-product hydrolysate powder in diets for Nile tilapia larvae / Hidrolisado proteico seco do resíduo da filetagem de tilápias em dietas para larvas de tilápia do Nilo

This study aimed to evaluate the digestibility of tilapia by-product protein hydrolysate powder (TBHP) from tilapia filleting by-product, and its inclusion in diets for Nile tilapia larvae. In order to determine the apparent digestibility coefficients, two diets were formulated, the reference diet and the test diet (20% of TBHP) and, to evaluate the inclusion, six diets were formulated, which were with 0.0, 2.0; 4.0; 6.0, and 8.0% of TBHP. The apparent digestibility coefficients of crude protein and gross energy were 89.5 and 98.3%, respectively. At levels above 4.0% of inclusion of TBHP, the weight, final length and weight gain were impaired, however, survival rate was higher (p 0.05). The TBHP can be used in diets for tilapia due to the high digestibility coefficients for crude protein and gross energy. The inclusion of up to 4.0% of TBHP does not affect the reproductive performance and survival rate of Nile tilapia larvae.(AU)

Objetivou-se avaliar a digestibilidade do hidrolisado proteico seco do resíduo da filetagem de tilápias (HPST) e sua inclusão em dietas para larvas de tilápia do Nilo. Para determinar os coeficientes de digestibilidade aparente, duas dietas foram elaboradas, referência e teste (com 20% do HPST) e para avaliação da inclusão, seis dietas foram formuladas com 0,0, 2,0; 4,0; 6,0, e 8,0% de HPST. Os coeficientes de digestibilidade aparente da proteína e energia bruta foram de 89,5 e 98,3%, respectivamente. Nos níveis acima de 4,0% de inclusão de HPST o peso e comprimento final e ganho em peso foram prejudicados, no entanto a sobrevivência foi maior (p 0,05). O HPST pode ser utilizado em dietas para tilápias em função dos elevados coeficientes de digestibilidade para proteína bruta e energia bruta. A inclusão de até 4,0% de HPST não afeta o desempenho produtivo e a sobrevivência de larvas de tilápias do Nilo.(AU)

Effect of phytase on digestibility of corn, sorghum and wheat bran by silver catfish (Rhamdia voulezi) / Efeito da fitase sobre a digestibilidade do milho, sorgo e farelo de trigo pelo jundiá (Rhamdia voulezi)

This study aimed to evaluate the digestibility of plant energetic ingredients, corn, sorghum and wheat bran, with and without phytase supplementation, in silver catfish (Rhamdia voulezi). The experimental design was completely randomized, represented by eight treatments, which consisted of the development of a reference diet and a test diet for each ingredient evaluated (corn, sorghum and wheat bran), with and without supplemental phytase. Diets were formulated so as to contain 70% reference feed and 30% test ingredient. The digestibility coefficients of dry matter and crude protein were significantly influenced only in relation to the evaluated ingredients. Phytase influenced the digestibility coefficients of energy and phosphorus, with interaction between food and the enzyme addition. The interaction between these two factors shows that the phytase efficiency is dependent on the type of vegetable ingredient used in the diet. The results suggest the supplementation of phytase for a higher nutrient digestibility of corn, sorghum and wheat bran by silver catifish (R. voulezi).

O objetivo do presente estudo foi avaliar a digestibilidade dos ingredientes energéticos vegetais, milho, sorgo e farelo de trigo, com e sem suplementação de fitase pelo jundiá (Rhamdia voulezi). O delineamento experimental foi inteiramente casualizado, representado por oito tratamentos, os quais consistiram na elaboração de uma dieta-referência e uma dieta- teste para cada ingrediente avaliado (milho, sorgo e farelo de trigo), com e sem a suplementação de fitase. As dietas foram fabricadas de modo que continham 70% da ração referência e 30% do ingrediente teste. Os coeficientes de digestibilidade da matéria seca e proteína bruta foram influenciados significativamente somente em relação aos ingredientes avaliados. A fitase influenciou nos coeficientes de digestibilidade da energia e do fósforo, onde também foi observada a interação entre os alimentos e a inclusão da enzima. A interação entre esses dois fatores demonstra que a eficiência da fitase é dependente do tipo de ingrediente vegetal utilizado na dieta. Pelos resultados obtidos sugere-se a suplementação de fitase visando maior digestibilidade dos nutrientes, do milho, sorgo e farelo de trigo pelo jundiá (R. voulezi).

Effect of phytase on digestibility of corn, sorghum and wheat bran by silver catfish (Rhamdia voulezi) / Efeito da fitase sobre a digestibilidade do milho, sorgo e farelo de trigo pelo jundiá (Rhamdia voulezi)

This study aimed to evaluate the digestibility of plant energetic ingredients, corn, sorghum and wheat bran, with and without phytase supplementation, in silver catfish (Rhamdia voulezi). The experimental design was completely randomized, represented by eight treatments, which consisted of the development of a reference diet and a test diet for each ingredient evaluated (corn, sorghum and wheat bran), with and without supplemental phytase. Diets were formulated so as to contain 70% reference feed and 30% test ingredient. The digestibility coefficients of dry matter and crude protein were significantly influenced only in relation to the evaluated ingredients. Phytase influenced the digestibility coefficients of energy and phosphorus, with interaction between food and the enzyme addition. The interaction between these two factors shows that the phytase efficiency is dependent on the type of vegetable ingredient used in the diet. The results suggest the supplementation of phytase for a higher nutrient digestibility of corn, sorghum and wheat bran by silver catifish (R. voulezi).(AU)

O objetivo do presente estudo foi avaliar a digestibilidade dos ingredientes energéticos vegetais, milho, sorgo e farelo de trigo, com e sem suplementação de fitase pelo jundiá (Rhamdia voulezi). O delineamento experimental foi inteiramente casualizado, representado por oito tratamentos, os quais consistiram na elaboração de uma dieta-referência e uma dieta- teste para cada ingrediente avaliado (milho, sorgo e farelo de trigo), com e sem a suplementação de fitase. As dietas foram fabricadas de modo que continham 70% da ração referência e 30% do ingrediente teste. Os coeficientes de digestibilidade da matéria seca e proteína bruta foram influenciados significativamente somente em relação aos ingredientes avaliados. A fitase influenciou nos coeficientes de digestibilidade da energia e do fósforo, onde também foi observada a interação entre os alimentos e a inclusão da enzima. A interação entre esses dois fatores demonstra que a eficiência da fitase é dependente do tipo de ingrediente vegetal utilizado na dieta. Pelos resultados obtidos sugere-se a suplementação de fitase visando maior digestibilidade dos nutrientes, do milho, sorgo e farelo de trigo pelo jundiá (R. voulezi).(AU)