Energy and nutrient digestibility from mulberry (Morus alba) leaf meal for Nile tilapia

The aim of this study was to determine the apparent digestibility coefficients and digestible values of crude protein, ethereal extract, gross energy and dry matter of mulberry leaf meal (MLM) (Morus albaL.) as Nile tilapia (Oreochromis niloticus) feed. A total of 135 Nile tilapia juveniles were used, and the indirect methodology (Cr2O3) was applied for digestibility determinations.Mulberry leave meal presented good apparent digestible coefficients of protein, ethereal extract and energy with respective values of 0.94, 0.58 and 0.39. The mulberry leave meal thus comprises adequate digestible protein and digestible energy values, similar or better than other leafy foods, presenting potential for inclusion in Nile tilapia diets.(AU)

Effect of Melatonin on the Reduction of Hepatic Steatosis and Intestinal Leptin Expression in Zebrafish Exposed to Fructose.

Melatonin is a hormone related to circadian rhythms and has potential clinical applications. Our objectives were to verify the effect of melatonin on the liver of zebrafish exposed to fructose and evaluate the expression of appetite-related genes (leptin, ghrelin, and melanocortin receptor 4 [MC4R]). Animals were divided into three groups: control (CG, n = 25), fructose (FG, n = 25), and fructose+melatonin (FMG, n = 25). The study was carried out in 8 weeks. FG and FMG were exposed to 2% fructose and FMG treated with 1 µM of melatonin. Histological liver studies and gene expression analyses of Leptin, Ghrelin, and MC4R (liver and intestines) were performed. FG developed hepatic steatosis, which did not occur with CG and FMG. Genetic expression of hepatic leptin and MC4R did not show significant difference among the groups. Animals exposed to fructose (FG) presented an increased expression of intestinal leptin compared to those administered with melatonin. Animals exposed to fructose gained weight and developed an important hepatic steatosis, but melatonin reduced significantly the hepatic damage. Intestinal leptin showed increased expression in the group exposed to fructose.

Effect of dietary crude glycerin on the productive performance of Nile tilapia fingerlings.

The aim of this study was to evaluate the effect of different crude glycerin levels in the diet of Nile tilapia fingerlings (mean initial weight 0.32 ± 0.06 g, n = 450) on growth performance parameters, whole-body composition, blood glucose and liver morphology. Crude glycerin was tested at six different levels (0, 4, 8, 12, 16, and 20%) in diets containing 30% digestible protein and 3,000 kcal kg-1 digestible energy. After 37 days of feeding, the inclusion of crude glycerin resulted in positive effects on final weight, visceral fat, weight gain, feed conversion, specific growth rate and feed intake. The different treatments did not influence fillet yield, glycemia, survival and hepatosomatic index, but intermediate levels of inclusion decreased the area of hepatocytes. Regarding fish body composition, significant differences were found in moisture and ash contents, with no changes in crude protein and total lipid. The inclusion of crude glycerin in the Nile tilapia diet improves growth performance without negatively affecting survival rate and glycemia of fingerlings.

Hepatoprotective Effect of Probiotic Lactobacillus rhamnosus GG Through the Modulation of Gut Permeability and Inflammasomes in a Model of Alcoholic Liver Disease in Zebrafish.

Objective: Alcoholic liver disease (ALD) is among the leading causes of death from liver disease. Among the factors involved in its pathogenesis are inflammation and increased intestinal permeability. The aim of this study was to assess the effect of Lactobacillus rhamnosus GG (LGG) on hepatic lipid accumulation, activation of inflammasomes, and gut permeability markers in experimental model of ALD with zebrafish.Methods: An experiment was conducted to assess the effective LGG dose capable of promoting intestinal colonization. Animals were divided into three groups (n = 64/group): ethanol group (E), ethanol + probiotic group (EP), and control group (C). Groups E and EP were exposed to 0.5% ethanol concentration for 28 days. At the end of this period, animals were euthanized, and livers were collected for Oil Red staining and assessment of the inflammasome system. Intestines were collected for evaluation of gut permeability markers.Results: The dose of 1.55 × 106 UFC LGG/fish/d promoted intestinal colonization. Group EP presented lower hepatic lipid accumulation, lower il-1ß expression, and higher cldn15a expression when compared to group E.Conclusions: Supplementation with LGG was protective for hepatic steatosis in ALD model. In addition, LGG influenced the modulation of the inflammatory response and markers of gut permeability, improving the gut barrier structure.

Alcoholic extract of propolis in Nile tilapia post-larvae and fingerlings' diets: effects on production performance, body composition and intestinal histology.

The aim of this study was to evaluate the production performance of Nile tilapia post-larvae and fingerlings fed with increasing levels of alcoholic extract of propolis into diets. In Experiment 1, 1800 post-larvae were distributed in 30 tanks, in a completely randomized design with five treatments composed by the inclusion of 0, 1, 2, 3 and 4 g of dry propolis/kg of feed, and six replicates. In experiment 2, 1600 fingerlings were distributed in the same system and designed as experiment 1. No significant effect was observed between treatments, for final weight, total and standard length, survival, and intestinal villus height. However, the propolis extract inclusion of 1 g/kg in Nile tilapia post-larvae and fingerlings' feed resulted in a better body condition factor and higher body protein deposition (p<0.05). The condition factor is an estimate for the future growth of the animals, possibly the fish treated with propolis extract will present better growth, survival and greater reproductive potential rates. The results of the present study demonstrate that alcoholic extract of propolis improves the nutritional condition of Nile tilapia post-larvae and fingerlings, potentially leading to increased productivity in subsequent stages, as well as leading to improvement in fingerlings muscle deposition.

Digestible protein requirement for Nile tilapia fed with rations based on soybean meal and corn / Exigência de proteína digestível para tilápias do Nilo alimentadascom rações à base de farelo de soja e milho

The objective was to determine the requirement of digestible protein (DP) for Nile tilapia fed with diets based on soybean meal and corn. Two hundred Nile tilapia juveniles, sexually reversed, were used for a trial period of 100 days. The animals were distributed in 20 boxes of 1000 L-1 in a random design with five treatments and four replications, the boxes were connected to a water recirculation system. Five isoenergetic diets were tested with different levels of digestible protein (DP): 20, 25, 30, 35 and 40%. At the end of the experimental period were evaluated the zootechnical performance data. A quadratic effect (p 0.05) was shown to parameters of final weight, weight gain, final length, fillet yield and visceral fat with the best points that ranged from 28.3 to 29.9% of DP. The largest area of hepatocytes was found to the lowest levels of DP in the diet (20 and 25%) compared to the other levels, which were similar. Thus, Nile tilapia has adequate performance for the consumption of diets based on soybean and corn meal and the recommended level is 28.3% of PD in these conditions.

Objetivou-se determinar a exigência de proteína digestível (PD) para a tilápia do Nilo, alimentada com dietas à base de farelo de soja e milho. Duzentos juvenis de tilápia do Nilo (32,80 ± 0,39 g), sexualmente revertidos, foram utilizados por um período experimental de 100 dias. Os animais foram distribuídos em 20 caixas de 1000L-1 em delineamento aleatório com cinco tratamentos e quatro repetições. As caixas eram ligadas a um sistema de recirculação de água. Foram testadas cinco dietas isoenergéticas com diferentes níveis de PD: 20, 25, 30, 35 e 40%. Ao final do período experimental, foram avaliados os dados de desempenho zootécnico. Um efeito quadrático (p < 0,05) foi mostrado aos parâmetros de peso final, ganho em peso, comprimento final, rendimento de filé e de gordura visceral com os melhores pontos que variaram de 28,3 a 29,9% de PD. A maior área dos hepatócitos foi encontrada para os níveis mais baixos de PD na dieta (20 e 25%), em comparação com os outros níveis, que foram semelhantes. Assim, pode-se afirmar que a tilápia do Nilo tem desempenho adequado para o consumo de dietas baseadas em farelo de soja e milho e o nível recomendado é de 28,3% PD nestas condições.

Digestible protein requirement for Nile tilapia fed with rations based on soybean meal and corn / Exigência de proteína digestível para tilápias do Nilo alimentadascom rações à base de farelo de soja e milho

The objective was to determine the requirement of digestible protein (DP) for Nile tilapia fed with diets based on soybean meal and corn. Two hundred Nile tilapia juveniles, sexually reversed, were used for a trial period of 100 days. The animals were distributed in 20 boxes of 1000 L-1 in a random design with five treatments and four replications, the boxes were connected to a water recirculation system. Five isoenergetic diets were tested with different levels of digestible protein (DP): 20, 25, 30, 35 and 40%. At the end of the experimental period were evaluated the zootechnical performance data. A quadratic effect (p 0.05) was shown to parameters of final weight, weight gain, final length, fillet yield and visceral fat with the best points that ranged from 28.3 to 29.9% of DP. The largest area of hepatocytes was found to the lowest levels of DP in the diet (20 and 25%) compared to the other levels, which were similar. Thus, Nile tilapia has adequate performance for the consumption of diets based on soybean and corn meal and the recommended level is 28.3% of PD in these conditions.(AU)

Objetivou-se determinar a exigência de proteína digestível (PD) para a tilápia do Nilo, alimentada com dietas à base de farelo de soja e milho. Duzentos juvenis de tilápia do Nilo (32,80 ± 0,39 g), sexualmente revertidos, foram utilizados por um período experimental de 100 dias. Os animais foram distribuídos em 20 caixas de 1000L-1 em delineamento aleatório com cinco tratamentos e quatro repetições. As caixas eram ligadas a um sistema de recirculação de água. Foram testadas cinco dietas isoenergéticas com diferentes níveis de PD: 20, 25, 30, 35 e 40%. Ao final do período experimental, foram avaliados os dados de desempenho zootécnico. Um efeito quadrático (p < 0,05) foi mostrado aos parâmetros de peso final, ganho em peso, comprimento final, rendimento de filé e de gordura visceral com os melhores pontos que variaram de 28,3 a 29,9% de PD. A maior área dos hepatócitos foi encontrada para os níveis mais baixos de PD na dieta (20 e 25%), em comparação com os outros níveis, que foram semelhantes. Assim, pode-se afirmar que a tilápia do Nilo tem desempenho adequado para o consumo de dietas baseadas em farelo de soja e milho e o nível recomendado é de 28,3% PD nestas condições.(AU)

Energia digestível e inclusão da glicerina bruta em dietas para juvenis de curimbatá / Digestible energy and inclusion of crude glycerin in diets for curimbatá juveniles

O curimbatá é um importante recurso pesqueiro, porém pouco se sabe sobre suas exigências nutricionais. O objetivo deste trabalho foi determinar o coeficiente de digestibilidade aparente (CDA) e o efeito da inclusão da glicerina bruta (GB) em dietas para juvenis do curimbatá Prochilodus lineatus. Foram coletadas fezes de peixes alimentados com dieta-referência, baseada em ingredientes de origem vegetal, e com dieta-teste, tendo o marcador inerte óxido de cromo III (0,1%). No experimento de crescimento foram utilizados 750 juvenis (18,71±2,70 g) em delineamento experimental inteiramente casualizado, com seis tratamentos (dietas contendo 0, 4, 8, 12, 16 e 20% GB) e cinco repetições, durante 64 dias. Para P. lineatus, a GB apresentou CDA de 0,76 para energia bruta e energia digestível de 2.850,99 kcal kg-1 da dieta. Os diferentes níveis de inclusão afetaram o peso final (PFM), conversão alimentar (CAA), taxa de crescimento específico (TCE) e ganho de peso (GPM), além dos níveis sanguíneos de glicose e de triglicerídeos. A análise de regressão mostrou efeito linear negativo das dietas sobre PFM, TCE e GPM e efeito linear positivo sobre CAA. A glicerina bruta pode ser utilizada como fonte de energia e sua inclusão em 4% da dieta promove um melhor desempenho produtivo do curimbatá.(AU)

The curimbatá is an important fishery resource, however, little is known about its nutritional requirements. This work aimed to determine the apparent digestibility coefficient (ADC) and the effect of the inclusion of crude glycerin (CG) in the diet for curimbatá (Prochilodus lineatus) juveniles. Feces were collected from fish fed with reference diet based on ingredients of plant origin and a test diet, having the inert marker chromium (III) oxide (0.1%). In the growth experiment, 750 juveniles (18.71 ± 2.70 g) were used in a completely randomized design, with six treatments (diets containing 0, 4, 8, 12, 16, and 20% CG) and five repetitions, for 64 days. For P. lineatus, CG presented ADC of 0.76 for crude energy and digestible energy of 2,850.99 kcal kg-1 of the diet. The different levels of inclusion affected the final weight (FW), feed conversion rate (FCR), specific growth rate (SGR), and weight gain (WG), in addition to blood levels of glucose and triglycerides. Regression analysis showed a negative linear effect of the diets on FW, SGR, and WG, and a positive linear effect on FCR. Crude glycerin can be used as an energy source and its inclusion in 4% of the diet improves the productive performance of curimbatá.(AU)

Energia digestível e inclusão da glicerina bruta em dietas para juvenis de curimbatá / Digestible energy and inclusion of crude glycerin in diets for curimbatá juveniles

O curimbatá é um importante recurso pesqueiro, porém pouco se sabe sobre suas exigências nutricionais. O objetivo deste trabalho foi determinar o coeficiente de digestibilidade aparente (CDA) e o efeito da inclusão da glicerina bruta (GB) em dietas para juvenis do curimbatá Prochilodus lineatus. Foram coletadas fezes de peixes alimentados com dieta-referência, baseada em ingredientes de origem vegetal, e com dieta-teste, tendo o marcador inerte óxido de cromo III (0,1%). No experimento de crescimento foram utilizados 750 juvenis (18,71±2,70 g) em delineamento experimental inteiramente casualizado, com seis tratamentos (dietas contendo 0, 4, 8, 12, 16 e 20% GB) e cinco repetições, durante 64 dias. Para P. lineatus, a GB apresentou CDA de 0,76 para energia bruta e energia digestível de 2.850,99 kcal kg-1 da dieta. Os diferentes níveis de inclusão afetaram o peso final (PFM), conversão alimentar (CAA), taxa de crescimento específico (TCE) e ganho de peso (GPM), além dos níveis sanguíneos de glicose e de triglicerídeos. A análise de regressão mostrou efeito linear negativo das dietas sobre PFM, TCE e GPM e efeito linear positivo sobre CAA. A glicerina bruta pode ser utilizada como fonte de energia e sua inclusão em 4% da dieta promove um melhor desempenho produtivo do curimbatá.

The curimbatá is an important fishery resource, however, little is known about its nutritional requirements. This work aimed to determine the apparent digestibility coefficient (ADC) and the effect of the inclusion of crude glycerin (CG) in the diet for curimbatá (Prochilodus lineatus) juveniles. Feces were collected from fish fed with reference diet based on ingredients of plant origin and a test diet, having the inert marker chromium (III) oxide (0.1%). In the growth experiment, 750 juveniles (18.71 ± 2.70 g) were used in a completely randomized design, with six treatments (diets containing 0, 4, 8, 12, 16, and 20% CG) and five repetitions, for 64 days. For P. lineatus, CG presented ADC of 0.76 for crude energy and digestible energy of 2,850.99 kcal kg-1 of the diet. The different levels of inclusion affected the final weight (FW), feed conversion rate (FCR), specific growth rate (SGR), and weight gain (WG), in addition to blood levels of glucose and triglycerides. Regression analysis showed a negative linear effect of the diets on FW, SGR, and WG, and a positive linear effect on FCR. Crude glycerin can be used as an energy source and its inclusion in 4% of the diet improves the productive performance of curimbatá.

Digestible protein requirement for Nile tilapia fed with rations based on soybean meal and corn

The objective was to determine the requirement of digestible protein (DP) for Nile tilapia fed with diets based on soybean meal and corn. Two hundred Nile tilapia juveniles, sexually reversed, were used for a trial period of 100 days. The animals were distributed in 20 boxes of 1000 L-1 in a random design with five treatments and four replications, the boxes were connected to a water recirculation system. Five isoenergetic diets were tested with different levels of digestible protein (DP): 20, 25, 30, 35 and 40%. At the end of the experimental period were evaluated the zootechnical performance data. A quadratic effect (p < 0.05) was shown to parameters of final weight, weight gain, final length, fillet yield and visceral fat with the best points that ranged from 28.3 to 29.9% of DP. The largest area of hepatocytes was found to the lowest levels of DP in the diet (20 and 25%) compared to the other levels, which were similar. Thus, Nile tilapia has adequate performance for the consumption of diets based on soybean and corn meal and the recommended level is 28.3% of PD in these conditions. 

Lactobacillus rhamnosus GG Effect on Behavior of Zebrafish During Chronic Ethanol Exposure.

Ethanol is a widely consumed drug, which acts on the central nervous system to induce behavioral alterations ranging from disinhibition to sedation. Recent studies have produced accumulating evidence for the therapeutic role of probiotic bacteria in behavior. We aimed to investigate the effect of Lactobacillus rhamnosus GG (LGG) on the behavior of adult zebrafish chronically exposed to ethanol. Adult wild-type zebrafish were randomly divided into four groups, each containing 15 fish. The following groups were formed: Control (C), received unsupplemented feed during the trial period; Probiotic (P), fed with feed supplemented with LGG; Ethanol (E), received unsupplemented feed and 0.5% of ethanol directly added to the tank water; and Probiotic+Ethanol (P+E), group under ethanol exposure (0.5%) and fed with LGG supplemented feed. After 2 weeks of exposure, the novel tank test was used to evaluate fish behavior, which was analyzed using computer-aided video tracking. LGG alone did not alter swimming behavior of the fish. Ethanol exposure led to robust behavioral effects in the form of reduced anxiety levels, as indicated by increased vertical exploration and more time spent in the upper region of the novel tank. The group exposed to ethanol and treated with LGG behaved similarly to animals exposed to ethanol alone. Taken together, these results show that zebrafish behavior was not altered by LGG per se, as seen in murine models. This was the first study to investigate the effects of a probiotic diet on behavior after a chronic ethanol exposure.

Efeitos da peletização e extrusão sobre a digestibilidade de ingredientes alternativos do semi-árido nordestino para a tilápia do Nilo / Pelleting and extrusion effects on the digestibility of alternative ingredients in northeast semi-arid for Nile tilapia

Foi avaliada a digestibilidade aparente dos nutrientes e energia da raspa de mandioca (RM), a farinha deresíduo de abate de caprinos/ovinos (FR) e a farinha de feno de maniçoba (FM), para a tilápia do Nilo emrações processadas na forma peletizada e na forma extrusada. Os coeficientes de digestibilidade aparente da proteína e energia brutas para a RM, o FR e a FM em rações peletizadas foram respectivamente 77,97 e 65,86%, 93,79 e 88,62%, 54,62 e 28,64%. Os coeficientes de digestibilidade aparente da proteína e energia brutas para a RM, o FR e a FM em rações extrusadas foram respectivamente 83,98 e 81,77%,62,55 e 89,81%, 52,73 e 28,09%. A extrusão contribuiu para a melhora da digestibilidade aparente daenergia da RM, porém diminuiu a digestibilidade aparente da fração protéica da FR. Os valores denutrientes digestíveis determinados no presente trabalho, independente do processamento, apontam paraum bom potencial para a utilização da raspa de mandioca e a farinha de resíduos de abate de caprinos/ovinos na composição de rações para a tilápia do Nilo, ao contrário do feno de maniçoba moído.(AU)

The apparent digestibility of nutrients and energy from cassava (RM), goats / sheep by products meal (FR) and maniçoba hay meal (FM) was evaluated for Nile tilapia in feed processing, as pelletized and extruded form. The apparent digestibility of crude protein and energy for the RM, FR and FM in pelletized diets were respectively 77.97 and 65.86%, 93.79 and 88.62%, 54.62 and 28.64%. The apparent digestibility of crude protein and energy for the RM, FR and FM in extruded feeds were respectively 83.98 and 81.77%, 62.55 and 89.81%, 52.73 and 28.09%. The extrusion contributed to the improvement of energy digestibility of the RM, but reduced the apparent digestibility of the protein fraction of FR. The values of digestible nutrients in the present work, regardless of the processing, suggest a good potential for the use of cassava flour and goats/sheep by products meal in the composition of diets for Nile tilapia, unlike hay maniçoba hay meal.(AU)

Digestible energy of crude glycerol for pacu and silver catfish / Energia digestível do glicerol bruto para o pacu e o jundiá

O aumento na produção mundial de biodiesel está gerando um excesso de glicerol, sem destinação definida. Uma alternativa para superar este problema é seu uso como fonte de energia na alimentação animal. No Brasil, o pacu (Piaractus mesopotamicus) é uma das espécies de peixes nativas mais cultivadas, enquanto que o jundiá (Rhamdia quelen) é apropriado para a produção na região subtropical. Considerando a falta de conhecimento sobre a utilização do glicerol bruto em rações para espécies de peixes Neotropicais, determinaram-se os coeficientes de digestibilidade aparente (CDAs) para a energia do glicerol bruto em P. mesopotamicus e R. quelen. A digestibilidade e o conteúdo de energia digestível do glicerol bruto podem ser considerados excelentes, mesmo quando comparados à energia de ingredientes comuns, como o milho e o trigo, apresentando para energia CDA de 0,97 e 0,89, e 15,2 e 13,95MJ kg-1 de energia digestível para o pacu e o jundiá, respectivamente. Por fim, o glicerol bruto é um ingrediente energético com bom potencial para dietas de peixes nativos do Brasil.

The increase in global biodiesel production is originating a glycerol surplus, which has no defined destination. An alternative to overcome this problem is its use as energy source in animal feeding. In Brazil, Pacu (Piaractus mesopotamicus) is one of the most farmed native fish species, whereas Silver catfish (Rhamdia quelen) is suitable for production in subtropical region. Considering little knowledge about crude glycerol utilization in feeds for Neotropical fish species, it was evaluated the apparent digestibility coefficients (ADCs) for energy of crude glycerol for P. mesopotamicus and R. quelen. The digestibility and digestible energy content of crude glycerol can be considered excellent even when compared to energy of common ingredients such as maize and wheat, presenting 0.97 and 0.89 of energy ADCs, and 15.2 and 13.95MJ kg-1 of digestible energy for Pacu and Silver catfish, respectively. In conclusion, crude glycerol is an energetic ingredient with good potential in Brazilian native fish diets.

Digestible energy of crude glycerol for pacu and silver catfish / Energia digestível do glicerol bruto para o pacu e o jundiá

O aumento na produção mundial de biodiesel está gerando um excesso de glicerol, sem destinação definida. Uma alternativa para superar este problema é seu uso como fonte de energia na alimentação animal. No Brasil, o pacu (Piaractus mesopotamicus) é uma das espécies de peixes nativas mais cultivadas, enquanto que o jundiá (Rhamdia quelen) é apropriado para a produção na região subtropical. Considerando a falta de conhecimento sobre a utilização do glicerol bruto em rações para espécies de peixes Neotropicais, determinaram-se os coeficientes de digestibilidade aparente (CDAs) para a energia do glicerol bruto em P. mesopotamicus e R. quelen. A digestibilidade e o conteúdo de energia digestível do glicerol bruto podem ser considerados excelentes, mesmo quando comparados à energia de ingredientes comuns, como o milho e o trigo, apresentando para energia CDA de 0,97 e 0,89, e 15,2 e 13,95MJ kg-1 de energia digestível para o pacu e o jundiá, respectivamente. Por fim, o glicerol bruto é um ingrediente energético com bom potencial para dietas de peixes nativos do Brasil.(AU)

The increase in global biodiesel production is originating a glycerol surplus, which has no defined destination. An alternative to overcome this problem is its use as energy source in animal feeding. In Brazil, Pacu (Piaractus mesopotamicus) is one of the most farmed native fish species, whereas Silver catfish (Rhamdia quelen) is suitable for production in subtropical region. Considering little knowledge about crude glycerol utilization in feeds for Neotropical fish species, it was evaluated the apparent digestibility coefficients (ADCs) for energy of crude glycerol for P. mesopotamicus and R. quelen. The digestibility and digestible energy content of crude glycerol can be considered excellent even when compared to energy of common ingredients such as maize and wheat, presenting 0.97 and 0.89 of energy ADCs, and 15.2 and 13.95MJ kg-1 of digestible energy for Pacu and Silver catfish, respectively. In conclusion, crude glycerol is an energetic ingredient with good potential in Brazilian native fish diets.(AU)

Effects of Lactobacillus rhamnosus GG on hepatic and serum lipid profiles in zebrafish exposed to ethanol.

Zebrafish is a powerful tool in pharmacological research and useful to identify new therapies. Probiotics can offer therapeutic options in alcoholic liver disease. This study was done in two independent experiments: first, we confirmed the intestinal colonization of probiotic Lactobacillus rhamnosus GG (LGG) after ethanol exposure. Second, four groups were performed: control (C), probiotic (P), ethanol (E), and probiotic+ethanol (P+E). Liver histology, hepatocytes morphometry, hepatic and serum lipid quantifications were conducted in second experiment. During 4 weeks, P and P+E groups were fed with LGG supplemented feed; E and C unsupplemented. E and P+E groups received 0.5% of ethanol added into tank water. Zebrafish exposed to ethanol (E group) presented intense liver steatosis after 28 days in contrast to the almost normalized liver histology of P+E group at the same period. Liver morphometry showed a significant enlargement of hepatocytes of E group after 4 weeks (p<0.0001). Serum triglycerides decreased in P+E group compared with C, P (p<0.001), and E (p=0.004), after 14 and 28 days similarly. Serum cholesterol was also decreased by LGG; P group decreased compared with C and E after 14 days (p=0.002 and p=0.007, respectively) and P+E group decreased significantly compared with E and C groups (p<0.0001) after 28 days. Hepatic triglycerides were reduced in P+E group after 28 days compared to E (p=0.006). The persistence of LGG in zebrafish intestines was demonstrated. LGG decreased serum levels of triglycerides and cholesterol and improved hepatic steatosis.

Efeitos da peletização e extrusão sobre a digestibilidade de ingredientes alternativos do semi-árido nordestino para a tilápia do Nilo / Pelleting and extrusion effects on the digestibility of alternative ingredients in northeast semi-arid for Nile tilapia

Foi avaliada a digestibilidade aparente dos nutrientes e energia da raspa de mandioca (RM), a farinha deresíduo de abate de caprinos/ovinos (FR) e a farinha de feno de maniçoba (FM), para a tilápia do Nilo emrações processadas na forma peletizada e na forma extrusada. Os coeficientes de digestibilidade aparente da proteína e energia brutas para a RM, o FR e a FM em rações peletizadas foram respectivamente 77,97 e 65,86%, 93,79 e 88,62%, 54,62 e 28,64%. Os coeficientes de digestibilidade aparente da proteína e energia brutas para a RM, o FR e a FM em rações extrusadas foram respectivamente 83,98 e 81,77%,62,55 e 89,81%, 52,73 e 28,09%. A extrusão contribuiu para a melhora da digestibilidade aparente daenergia da RM, porém diminuiu a digestibilidade aparente da fração protéica da FR. Os valores denutrientes digestíveis determinados no presente trabalho, independente do processamento, apontam paraum bom potencial para a utilização da raspa de mandioca e a farinha de resíduos de abate de caprinos/ovinos na composição de rações para a tilápia do Nilo, ao contrário do feno de maniçoba moído.

The apparent digestibility of nutrients and energy from cassava (RM), goats / sheep by products meal (FR) and maniçoba hay meal (FM) was evaluated for Nile tilapia in feed processing, as pelletized and extruded form. The apparent digestibility of crude protein and energy for the RM, FR and FM in pelletized diets were respectively 77.97 and 65.86%, 93.79 and 88.62%, 54.62 and 28.64%. The apparent digestibility of crude protein and energy for the RM, FR and FM in extruded feeds were respectively 83.98 and 81.77%, 62.55 and 89.81%, 52.73 and 28.09%. The extrusion contributed to the improvement of energy digestibility of the RM, but reduced the apparent digestibility of the protein fraction of FR. The values of digestible nutrients in the present work, regardless of the processing, suggest a good potential for the use of cassava flour and goats/sheep by products meal in the composition of diets for Nile tilapia, unlike hay maniçoba hay meal.

Essential oils in Nile tilapia fingerlings fed / Óleos essenciais na alimentação de alevinos de tilápia do Nilo

The use of herbal extracts and essential oils as additives for fish feed have shown great potential, still requiring that the field trials are performed to determine the final use of these compounds. Aiming to evaluate the growth performance of Nile tilapia fingerlings Oreochromis niloticus fed with different levels essential oils, an experiment was conducted in a completely randomized design with 5 treatments and 4 replicates: 0,000, 0,005, 0,010, 0,015 and 0,020% of a commercial blend microencapsulate based on essential oils in the diet. Net tanks with volume of 1m3 were used as experimental units with a stocking density of 50 fingerling m3. At the end of 69 days of culture there was no relation between levels of essential oils and the parameters of survival (%), weight gain (g), growth rate (g/day) and feed conversion. On the other hand there was a quadratic relationship of body protein content for different levels of the commercial blend microencapsulate in the diet with the maximum point estimated at 0,0097% inclusion. Therefore, it is concluded that the levels of essential oils used in this study did not provide evidence of the positive effect on the performance of Nile tilapia fingerlings, mainly as a growth promoter.

A utilização de óleos essenciais e extratos herbais como aditivos para alimentação dos peixes têm demonstrado grande potencial, necessitando ainda que ensaios a campo sejam realizados para se determinar a utilização definitiva destes compostos. Com o objetivo de avaliar o desempenho zootécnico de alevinos de Tilápia do Nilo Oreochromis niloticus alimentados com ração contendo diferentes níveis de óleos essenciais, realizou-se um experimento em delineamento inteiramente casualizado com 5 tratamentos e 4 repetições: 0.000; 0,005; 0,010; 0,015 e 0,020% de um aditivo comercial à base de óleos essenciais na ração. Tanques-rede com volume de 1m3 foram utilizados como unidades experimentais com uma densidade de estocagem de 50 alevinos.m-3. Ao final de 69 dias de cultivo não se verificou uma relação entre os diferentes níveis de óleos essenciais e os parâmetros de sobrevivência (%), ganho em peso (g), taxa de crescimento (g.dia-1) e conversão alimentar aparente (CAA). Por outro lado verificou-se uma relação quadrática para o conteúdo de proteína corporalcom ponto de máximo estimado em 0,0097% de inclusão. Sendo assim, conclui-se que os níveis do aditivo utilizados no presente estudo não forneceram evidências do efeito positivo dos óleos essenciais sobre o desempenho de alevinos de tilápia do Nilo, principalmente como promotor de crescimento.

Essential oils in Nile tilapia fingerlings fed / Óleos essenciais na alimentação de alevinos de tilápia do Nilo

The use of herbal extracts and essential oils as additives for fish feed have shown great potential, still requiring that the field trials are performed to determine the final use of these compounds. Aiming to evaluate the growth performance of Nile tilapia fingerlings Oreochromis niloticus fed with different levels essential oils, an experiment was conducted in a completely randomized design with 5 treatments and 4 replicates: 0,000, 0,005, 0,010, 0,015 and 0,020% of a commercial blend microencapsulate based on essential oils in the diet. Net tanks with volume of 1m3 were used as experimental units with a stocking density of 50 fingerling m3. At the end of 69 days of culture there was no relation between levels of essential oils and the parameters of survival (%), weight gain (g), growth rate (g/day) and feed conversion. On the other hand there was a quadratic relationship of body protein content for different levels of the commercial blend microencapsulate in the diet with the maximum point estimated at 0,0097% inclusion. Therefore, it is concluded that the levels of essential oils used in this study did not provide evidence of the positive effect on the performance of Nile tilapia fingerlings, mainly as a growth promoter.(AU)

A utilização de óleos essenciais e extratos herbais como aditivos para alimentação dos peixes têm demonstrado grande potencial, necessitando ainda que ensaios a campo sejam realizados para se determinar a utilização definitiva destes compostos. Com o objetivo de avaliar o desempenho zootécnico de alevinos de Tilápia do Nilo Oreochromis niloticus alimentados com ração contendo diferentes níveis de óleos essenciais, realizou-se um experimento em delineamento inteiramente casualizado com 5 tratamentos e 4 repetições: 0.000; 0,005; 0,010; 0,015 e 0,020% de um aditivo comercial à base de óleos essenciais na ração. Tanques-rede com volume de 1m3 foram utilizados como unidades experimentais com uma densidade de estocagem de 50 alevinos.m-3. Ao final de 69 dias de cultivo não se verificou uma relação entre os diferentes níveis de óleos essenciais e os parâmetros de sobrevivência (%), ganho em peso (g), taxa de crescimento (g.dia-1) e conversão alimentar aparente (CAA). Por outro lado verificou-se uma relação quadrática para o conteúdo de proteína corporalcom ponto de máximo estimado em 0,0097% de inclusão. Sendo assim, conclui-se que os níveis do aditivo utilizados no presente estudo não forneceram evidências do efeito positivo dos óleos essenciais sobre o desempenho de alevinos de tilápia do Nilo, principalmente como promotor de crescimento.(AU)

Crude protein requeriment to pacamã juveniles / Exigência de proteína bruta para juvenis de pacamã

Pacamã (Lophiosilurus alexandri) is a species of carnivorous fish, suitable for farming, but little studied. The aim of this study was to determinate crude protein (CP) requirement to pacamã, L. alexandri, in juvenile phase, an experiment was conducted during 45 days in a completely randomized design, with five treatments (36.2, 38.2, 42.0, 44.4, and 48.8% CP of diet) and four replications, where a hundred juvenile fishes (5.19 ± 0.01 g) were distributed in twenty 36 L aquaria. Each aquarium with five juveniles was considered an experimental unit. The parameters evaluated were final weight, percentage weight gain, specific growth rate, survival rate, hepatosomatic index, carcass yield with and without head, total length, head length, width, and height. By the regression analysis was verify a (P0.05). Thus, it is recommended to use feed containing 36.2% of crude protein to pacamã (L. alexandri) juveniles.

O pacamã (Lophiosilurus alexandri) é uma espécie de peixe com hábito alimentar carnívoro, apropriada para o cultivo, porém, ainda pouco estudada. O objetivo deste estudo foi determinar a exigência de proteína bruta (PB) do pacamã, L. alexandri, na fase juvenil. O experimento foi conduzido por um período de 45 dias utilizando um delineamento inteiramente casualizado, com cinco tratamentos (dieta contendo 36,2; 38,2; 42,0; 44,4 e 48,8% de PB) e quatro repetições cada, onde 100 juvenis (5,19 ± 0,01g) foram distribuídos em 20 caixas com volume útil de 36 L, sendo considerada como unidade experimental uma caixa com cinco juvenis. Foram avaliados os parâmetros de peso final, percentagem de ganho de peso, taxa de crescimento específico, sobrevivência, índice hepatossomático, rendimento de carcaça com e sem cabeça, comprimento total, comprimento da cabeça, largura e altura. Pela análise de regressão foi verificada uma redução linear (P0,05). Deste modo, recomenda-se a utilização de rações contendo entre 36,2% de proteína bruta para juvenis de pacamã (L. alexandri).

Crude protein requeriment to pacamã juveniles / Exigência de proteína bruta para juvenis de pacamã

Pacamã (Lophiosilurus alexandri) is a species of carnivorous fish, suitable for farming, but little studied. The aim of this study was to determinate crude protein (CP) requirement to pacamã, L. alexandri, in juvenile phase, an experiment was conducted during 45 days in a completely randomized design, with five treatments (36.2, 38.2, 42.0, 44.4, and 48.8% CP of diet) and four replications, where a hundred juvenile fishes (5.19 ± 0.01 g) were distributed in twenty 36 L aquaria. Each aquarium with five juveniles was considered an experimental unit. The parameters evaluated were final weight, percentage weight gain, specific growth rate, survival rate, hepatosomatic index, carcass yield with and without head, total length, head length, width, and height. By the regression analysis was verify a (P<0.01) linear decrease to performance parameters in function to ration protein growth, however to Tukey test the best (P<0.01) result was obtained with 36.2% of CP. There was no influence of treatments on the other evaluated parameters (p>0.05). Thus, it is recommended to use feed containing 36.2% of crude protein to pacamã (L. alexandri) juveniles.(AU)

O pacamã (Lophiosilurus alexandri) é uma espécie de peixe com hábito alimentar carnívoro, apropriada para o cultivo, porém, ainda pouco estudada. O objetivo deste estudo foi determinar a exigência de proteína bruta (PB) do pacamã, L. alexandri, na fase juvenil. O experimento foi conduzido por um período de 45 dias utilizando um delineamento inteiramente casualizado, com cinco tratamentos (dieta contendo 36,2; 38,2; 42,0; 44,4 e 48,8% de PB) e quatro repetições cada, onde 100 juvenis (5,19 ± 0,01g) foram distribuídos em 20 caixas com volume útil de 36 L, sendo considerada como unidade experimental uma caixa com cinco juvenis. Foram avaliados os parâmetros de peso final, percentagem de ganho de peso, taxa de crescimento específico, sobrevivência, índice hepatossomático, rendimento de carcaça com e sem cabeça, comprimento total, comprimento da cabeça, largura e altura. Pela análise de regressão foi verificada uma redução linear (P<0.01) nos parâmetros de desempenho em função do nível protéico da ração. Quando comparados pelo teste de Tukey, o melhor resultado (P<0.01) foi obtido com 36,2% de PB. Não houve influência dos tratamentos nos outros parâmetros avaliados (p>0,05). Deste modo, recomenda-se a utilização de rações contendo entre 36,2% de proteína bruta para juvenis de pacamã (L. alexandri).(AU)