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1.
Insects ; 12(11)2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34821766

RESUMO

Hermetia illucens and Tenebrio molitor were tested on account of their potential to replace fish protein in feed. Two levels of replacement for H. illucens, 30% and 50% (H30 and H50), and one for T. molitor, 50% (T50), as well as an additional diet with a modified fatty acid fraction (H50M), were investigated in relation to juvenile Sparus aurata growth indices, enzyme activities and gut microbiome. A T50 diet showed similar results to a control (C) diet, with no significant differences regarding morphological indices and minor differences for nutritional indices. Regarding the gut microbiome, H50M was the diet which showed the more similar prokaryotic community to C, which suggests that fatty acid fractions might influence the composition of the gut microbiome. Nevertheless, differences appeared to be related to a redistribution of dominant species, while changes in species affiliation were limited to minoritary species. The positive correlation between some of these minoritary species (Peptostreptococcus russellii, Streptococcus dysgalactiae and Weisella confusa) and several fish growth parameters might explain differences between control and insect diets. Deciphering such uncertainty and revealing the potential role these unusual species may play on fish performance should be addressed in future investigations.

2.
Front Physiol ; 8: 427, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28670288

RESUMO

The culture of the common octopus (Octopus vulgaris) is promising since the species has a relatively short lifecycle, rapid growth, and high food conversion ratios. However, recent attempts at successful paralarvae culture have failed due to slow growth and high mortality rates. Establishing an optimal nutritional regime for the paralarvae seems to be the impeding step in successful culture methods. Gaining a thorough knowledge of food regulation and assimilation is essential for paralarvae survival and longevity under culture conditions. The aim of this study, then, was to elucidate the characteristic metabolic organization of octopus paralarvae throughout an ontogenic period of 12 days post-hatching, as well as assess the effect of diet enrichment with live prey containing abundant marine phospholipids. Our results showed that throughout the ontogenic period studied, an increase in anaerobic metabolism took place largely due to an increased dependence of paralarvae on exogenous food. Our studies showed that this activity was supported by octopine dehydrogenase activity, with a less significant contribution of lactate dehydrogenase activity. Regarding aerobic metabolism, the use of amino acids was maintained for the duration of the experiment. Our studies also showed a significant increase in the rate of oxidation of fatty acids from 6 days after-hatching. A low, although sustained, capacity for de novo synthesis of glucose from amino acids and glycerol was also observed. Regardless of the composition of the food, glycerol kinase activity significantly increased a few days prior to a massive mortality event. This could be related to a metabolic imbalance in the redox state responsible for the high mortality. Thus, glycerol kinase might be used as an effective nutritional and welfare biomarker. The studies in this report also revealed the important finding that feeding larvae with phospholipid-enriched Artemia improved animal viability and welfare, significantly increasing the rate of survival and growth of paralarvae.

3.
Redox Biol ; 11: 682-687, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28167333

RESUMO

The objective of the present study is to characterize the metabolic and antioxidant profile of white muscle of shi drum in two sites of the body, anterior dorsal (AM) and posterior dorsal (PM) portions. In addition, it will be analyzed the possible effect of starvation and a subsequent refeeding, with two different protocols, pair feeding and ad libitum. Activities of key enzymes of intermediary metabolism and of antioxidant enzymes, as well as lipid peroxidation, as an index of oxidative stress, were evaluated. The results indicate the existence of a regional asymmetry of the metabolic capacities of the white muscle of shi drum, which is likely related to the different contribution to swimming of the body regions examined. Starvation induces a metabolic depression that is more marked in those activities that support burst swimming in PM, while those activities supporting maintenance requirements are conserved. The greatest energy demands during starvation appear to lie in AM, which showed the highest oxidative metabolism rate. The increased use of fatty acids as energy source for AM leads to oxidative stress. A period of more than four weeks of refeeding for full restoration of metabolic capacities in AM is needed, probably related to the higher muscle mass located in this region. On the contrary, all enzyme activities in PM returned to control levels in both refeeding protocols, but pair feeding seems to be advantageous since compensatory growth has been taking place without signs of oxidative stress. This work was addressed to gain knowledge on the physiology of a promising fish species in aquaculture like shi drum. The results displayed here show how the starving and further re-feeding events could generate oxidative stress situations characterized by high lipid peroxidation levels which may influence negatively on the quality of the edible part of the fish. This study opens an interesting field on this fish species which deserves being investigated in the future.


Assuntos
Antioxidantes/metabolismo , Fígado/metabolismo , Músculo Esquelético/metabolismo , Estresse Oxidativo , Animais , Peixes/metabolismo , Peroxidação de Lipídeos/genética , Inanição
4.
Artigo em Inglês | MEDLINE | ID: mdl-27553761

RESUMO

Common dentex (Dentex dentex) is an appreciated carnivorous fish with high growth rate and life cycle adaptable to existing farming techniques. Since the use of carbohydrates is an economic and sustainable alternative for a protein-sparing effect, the study of how this macronutrient affects the welfare of carnivorous species must be studied. The aim of the present study was to evaluate the effects of different types and levels of carbohydrates on common dentex oxidative status. Nine isonitrogenous (43%) and isoenergetic (22MJkg-1) diets were formulated combining three types (pregelatinized starch-PS, dextrin-Dx and maltodextrin-Mx) and three levels (12, 18 and 24%) of carbohydrates. The activities of catalase-CAT, superoxide dismutase-SOD, glutathione peroxidase-GPX, glutathione reductase-GR and glucose 6-phosphate dehydrogenase-G6PDH, SOD isoenzymatic profile, lipid peroxidation-LPO and protein oxidation-PO were determined in liver and white muscle. SOD and CAT were not affected. GPX in liver and white muscle and GR in liver increased at higher inclusion carbohydrates levels. The lowest levels of GR and G6PDH in both tissues and LPO in liver were observed in maltodextrin groups. No significant effects by carbohydrate source were observed in liver PO and white muscle LPO. Regarding carbohydrate level effect, 18% and 24% dietary inclusion level decreased LPO in white muscle and PO in liver. LPO in liver was also decreased at 24% inclusion level. Altogether, results indicate the use of carbohydrates as an alternative energy source does not produce negative effects on oxidative status of common dentex, on the contrary, even contribute to their oxidative protection.


Assuntos
Carnivoridade , Carboidratos da Dieta/administração & dosagem , Enzimas/metabolismo , Peixes/metabolismo , Estresse Oxidativo , Animais , Fígado/enzimologia , Fígado/metabolismo , Músculos/enzimologia , Músculos/metabolismo
5.
Artigo em Inglês | MEDLINE | ID: mdl-25668294

RESUMO

The present study was aimed to evaluate the capacity of common dentex (Dentex dentex) to efficiently use dietary carbohydrates. So, the effects of different type and levels of carbohydrates on growth performance, feed utilization, fish composition, plasma metabolites and key metabolic pathways in liver and white muscle of common dentex are presented. Nine isonitrogenous (43%) and isoenergetic (22 MJ kg(-1)) diets were formulated combining three types, pregelatinized starch (PS), dextrin (Dx) and maltodextrin (Mx), and three levels (12, 18 and 24%) of carbohydrates. Growth performance was not significantly influenced by treatments. The best feed utilization was observed in 18% Mx group. Higher hepatic lipid content was found in fish fed lower dietary carbohydrate levels. PS induced higher liver and white muscle hexokinase and pyruvate kinase activities compared to the lower values observed for Mx. Malic enzyme and glucose 6-phosphate dehydrogenase in liver and white muscle were lower in Mx group. The influence of dietary carbohydrates source was more noticeable than those induced by the carbohydrate level, when glycolysis and lipogenesis pathways were considered. Common dentex is able to use properly dietary carbohydrates, although optimal dietary inclusion levels are below 24%. The greater protein-sparing effect was promoted by the less complex carbohydrate (maltodextrin) and the best feed utilization indices were obtained at intermediate levels of inclusion (18%).


Assuntos
Ração Animal , Carboidratos da Dieta/administração & dosagem , Peixes/metabolismo , Animais
6.
J Comp Physiol B ; 182(1): 63-76, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21698525

RESUMO

The present study examines the particular metabolic strategies of the sturgeon Acipenser naccarii in facing a period of prolonged starvation (72 days) and subsequent refeeding (60 days) compared to the trout Oncorhynchus mykiss response under similar conditions. Plasma metabolites, endogenous reserves, and the activity of intermediate enzymes in liver and white muscle were evaluated. This study shows the mobilization of tissue reserves during a starvation period in both species with an associated enzymatic response. The sturgeon displayed an early increase in hepatic glycolysis during starvation. The trout preferentially used lactate for gluconeogenesis in liver and white muscle. The sturgeon had higher lipid-degradation capacity and greater synthesis of hepatic ketone bodies than the trout, although this latter species also showed strong synthesis of ketone bodies during starvation. During refeeding, the metabolic activity present before starvation was recovered in both fish, with a reestablishment of tissue reserves, plasmatic parameters (glucemia and cholesterol), and enzymatic activities in the liver and muscle. A compensatory effect in enzymes regarding lipids, ketone bodies, and oxidative metabolism was displayed in the liver of both species. There are metabolic differences between sturgeon and trout that support the contention that the sturgeon has common characteristics with elasmobranchs and teleosts.


Assuntos
Enzimas/metabolismo , Peixes/metabolismo , Fígado/metabolismo , Músculo Esquelético/metabolismo , Oncorhynchus mykiss/metabolismo , Animais , Colesterol/sangue , Ingestão de Alimentos/fisiologia , Peixes/fisiologia , Glicogênio/metabolismo , Corpos Cetônicos/metabolismo , Metabolismo dos Lipídeos , Fígado/enzimologia , Músculo Esquelético/enzimologia , Especificidade da Espécie , Inanição
7.
Comp Biochem Physiol C Toxicol Pharmacol ; 150(4): 537-45, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19664720

RESUMO

A wide range of antioxidant mechanisms are present in fish maintaining an adequate "oxidative balance". When this balance tilts in favor of the oxidant agents "oxidative stress" arises with detrimental effects in molecules of great biological importance. Little has been reported about the influence of different dietary energy sources on antioxidant defenses in fish. The influence of different dietary macronutrient combinations on the key antioxidant enzyme activity, the oxidative damage to lipids and proteins and the possible modifications in the SOD isoenzymatic pattern were evaluated in liver, white muscle, heart and erythrocytes of common dentex (Dentex dentex). Four experimental diets with different protein:lipid:carbohydrate ratios (43/16/28; 43/24/4; 38/19/28 and 38/24/13) were formulated. In general, neither different dietary macronutrient levels nor the interaction among them induces substantial modifications in enzymatic antioxidant defense mechanisms. Two constitutive SOD isoforms, CuZn-SOD I and Mn-SOD, were detected in the tissues analyzed in all experimental groups, independently of diet formulation, but, a third SOD isoenzyme, CuZn-SOD II seems to be induced in white muscle by higher dietary protein levels. Densitometric analyses of western blotting membranes revealed higher CuZn-SOD expression in the heart of dentex fed on lower dietary protein levels, although these differences did not correlate with the SOD activity. Finally, a direct relation exists between the lipid or protein intake level and occurrence of oxidative damage in different tissue components.


Assuntos
Antioxidantes/metabolismo , Carboidratos da Dieta/farmacologia , Gorduras na Dieta/farmacologia , Proteínas Alimentares/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Perciformes/metabolismo , Animais , Catalase/metabolismo , Carboidratos da Dieta/metabolismo , Gorduras na Dieta/metabolismo , Proteínas Alimentares/metabolismo , Metabolismo Energético/efeitos dos fármacos , Eritrócitos/enzimologia , Alimentos Formulados , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Isoenzimas/metabolismo , Metabolismo dos Lipídeos , Peroxidação de Lipídeos , Fígado/enzimologia , Músculo Esquelético/enzimologia , Miocárdio/enzimologia , Distribuição Aleatória , Padrões de Referência , Solubilidade , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/análise
8.
Artigo em Inglês | MEDLINE | ID: mdl-19501667

RESUMO

Digestive physiology of on-growing common dentex (Dentex dentex), including protease, amylase and lipase activity in stomach, pyloric caeca, anterior and posterior intestine, was evaluated. The influence of dietary macronutrient balance on these digestive processes was also assessed. Four experimental diets with different protein:lipid:carbohydrate ratios (43/16/28; 43/24/4; 38/19/28 and 38/24/13) were formulated. The highest activity for acid proteases was located in the stomach at pH 1.5. Alkaline proteolytic activities showed the highest values in the pyloric caeca and posterior intestine at pH 8.5-9.0. Dentex showed substantial amylase activity in the pyloric caeca and posterior intestine. Lipase activity was higher in the pyloric caeca, anterior and posterior intestine and was not detected in the stomach. Feed composition influenced alkaline protease activity in the anterior and posterior intestine and was higher for the diet with less protein and more carbohydrates. Enhanced amylase activity was observed in the pyloric caeca and posterior intestine in those groups fed on higher carbohydrate and lower lipid level diets. High dietary carbohydrate levels produced the highest lipase activity but this only occurred in the anterior intestine. We can conclude that the digestive tract of dentex adapts well to protein digestion and possesses a high potential for digesting the other dietary macronutrients, too. Dietary carbohydrate content seems to induce changes in protease, amylase and lipase activity.


Assuntos
Trato Gastrointestinal/enzimologia , Amilases/metabolismo , Animais , Carboidratos da Dieta/metabolismo , Carboidratos da Dieta/farmacologia , Gorduras na Dieta/metabolismo , Gorduras na Dieta/farmacologia , Proteínas Alimentares/metabolismo , Alimentos Formulados , Concentração de Íons de Hidrogênio , Intestinos/enzimologia , Lipase/metabolismo , Peptídeo Hidrolases/metabolismo , Perciformes/metabolismo , Piloro/enzimologia , Estômago/enzimologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-19000780

RESUMO

Rainbow trout maintained at crowding or noncrowding conditions were fed on five experimental diets that were formulated considering two levels of vitamin E (25.6 and 275.6 mg/kg diet), vitamin C (0 and 1000 mg/kg diet) and HUFA (12.5 and 30.5 g/kg diet): -E-HUFA, -E+HUFA, +E-HUFA, +E+HUFA, -C+E+HUFA. Hematological parameters, the activity of some antioxidant enzymes and lipid peroxidation from RBC were evaluated. The SOD isoenzyme pattern was analyzed by nondenaturing PAGE. Hematological response to crowding stress was manifested by increased hemoglobin and RBC count in most of the crowded groups. Antioxidant enzyme activity was clearly affected by dietary HUFA levels, with uncrowded fish fed on +HUFA diets showing a higher SOD activity compared to those fed on -HUFA diets. In uncrowded groups, only one CuZn-SOD isozyme was detected, whereas in the crowded fish a great variability was revealed with up to five isozymes. G6PDH activity was increased in uncrowded -E+HUFA fish compared to the remaining groups. Lipid peroxidation was significantly increased in -E+HUFA fish regardless of fish density. Data supported the negative correlation of lipid peroxidation and hematocrit or hemoglobin explained by decreased erythrocyte stability. Dietary imbalances in vitamin E and HUFA supplementation may promote oxidative stress which triggers hematological deterioration, which in turn would affect the whole hematological status and ultimately fish welfare.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Aglomeração , Dieta , Ácidos Graxos Insaturados/administração & dosagem , Oncorhynchus mykiss/sangue , Vitamina E/administração & dosagem , Vitaminas/administração & dosagem , Animais , Enzimas/sangue , Índices de Eritrócitos , Eritrócitos/efeitos dos fármacos , Eritrócitos/enzimologia , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos
10.
Artigo em Inglês | MEDLINE | ID: mdl-19049895

RESUMO

The influence of the dietary macronutrient balance on the intermediary metabolism of common dentex (Dentex dentex L.) was evaluated. Four experimental diets combining high and low levels of macronutrients were formulated. Dentex fed on 43% protein had higher liver and muscle lipid content, corresponding with an increased hepatic G6PDH activity. This "excess" of hepatic lipids at higher protein levels could be used to obtain energy as would be reflected by hepatic HOAD. In the liver, 43% of dietary protein induced higher AlaAT and FBPase activities. Similarly, dentex fed on the P(43)C(28) and P(38)C(28) diets showed an increased hepatic and muscular gluconeogenic pathways (higher FBPase activity) from amino acids (elevated AlaAT) and/or glycerol (elevated GK). However, changes in glycemia were not observed among dietary treatments. At coronary level, the use of lower dietary protein induced an increase in the activity of glycolytic (PK and HK-IV) and lipolytic (HOAD) enzymes. Considering the overall results and the experimental conditions, it could be suggested that dietary protein could be reduced until 38% without affecting negatively the normal physiology of dentex. Moreover, high dietary carbohydrate levels could not be used efficiently by dentex given that gluconeogenesis occurs.


Assuntos
Dieta , Carboidratos da Dieta/farmacologia , Proteínas Alimentares/farmacologia , Metabolismo Energético/efeitos dos fármacos , Perciformes/metabolismo , Alanina Transaminase/metabolismo , Aminoácidos/metabolismo , Animais , Carboidratos da Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Frutose-Bifosfatase/metabolismo , Glucosefosfato Desidrogenase/metabolismo , Glicerol/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Músculo Esquelético/metabolismo
11.
Artigo em Inglês | MEDLINE | ID: mdl-18328757

RESUMO

The digestive enzyme activities were determined in Adriatic sturgeon and rainbow trout during starvation and refeeding period. Overall, the digestive enzyme activities are affected in the same sense in both species. The protease and lipase activities were decreased later than amylase activity. Even after 1 month of starvation, both species would be prepared to digest protein and lipids in an effective way. After 72 days of starvation, the digestive machinery of the sturgeon and of the trout shows an altered capacity to digest macronutrients. The capacity to digest proteins and lipids, after 60 days of refeeding, begins to become re-established in sturgeon and trout. In contrast, in this period, the capacity to digest carbohydrates remains depressed in both species.


Assuntos
Digestão/fisiologia , Oncorhynchus mykiss/metabolismo , Período Pós-Prandial/fisiologia , Inanição/enzimologia , Truta/metabolismo , Amilases/metabolismo , Animais , Carboidratos da Dieta/metabolismo , Privação de Alimentos , Lipase/metabolismo , Lipólise , Peptídeo Hidrolases/metabolismo , Proteínas/metabolismo , Recuperação de Função Fisiológica , Inanição/fisiopatologia
12.
Artigo em Inglês | MEDLINE | ID: mdl-15955717

RESUMO

Variations of Na(+)/K(+)-ATPase activity and fatty-acid composition in the gills of the sturgeon Acipenser naccarii subjected to progressive acclimation to full seawater (35 ppt) were determined in relation to the hypo-osmoregulatory capacity of this species in the hyperosmotic medium. Blood samples were taken and gills arches were removed at intermediate salinity levels between 0 and 35 ppt and after 20 days at constant salinity (35 ppt). Plasma osmolality and Na(+)/K(+)-ATPase activity increased significantly with growing environmental salinity. Total saturated fatty acids (SFAs) decreased, while total polyunsaturated fatty acids (PUFAs) increased significantly with increasing salinity due mainly to changes in n-3 PUFAs (20:5n-3 and 22:6n-3). The n-3/n-6 ratio increased significantly during the acclimation process. The results show a direct relationship between salinity, increased gill Na(+)/K(+)-ATPase activity and ultrastructural changes of the gill chloride cells. Changes in the fatty-acid composition in gills of A. naccarii during progressive acclimation to full seawater suggest that variations of gill fatty acids may also have a role in osmoregulatory mechanisms.


Assuntos
Aclimatação/fisiologia , Peixes/fisiologia , Brânquias/fisiologia , Água do Mar , ATPase Trocadora de Sódio-Potássio/fisiologia , Equilíbrio Hidroeletrolítico/fisiologia , Animais , Ácidos Graxos/metabolismo , Peixes/sangue , Água Doce , Brânquias/ultraestrutura , Microscopia Eletrônica de Transmissão , Concentração Osmolar
13.
Comp Biochem Physiol C Toxicol Pharmacol ; 139(1-3): 153-61, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15556078

RESUMO

The aim of this work was to evaluate the effects of prolonged starvation and refeeding on antioxidant status and some metabolic-related parameters in common dentex (Dentex dentex) liver. Fish deprived of food for 5 weeks showed a significant increase in lipid peroxidation, measured as malondialdehyde (MDA) levels. The activity of the antioxidative enzymes superoxide dismutase (SOD), catalase, and glutathione peroxidase (GPX) in starved fish significantly increased (by 42%, 22%, and 52%, respectively), whereas glutathione reductase (GR) activity was significantly depressed by 53% compared to controls. No qualitative changes in the SOD isoenzymatic pattern were detected by nondenaturing PAGE analysis, but the isoforms corresponding to CuZn-SOD I and II were enhanced in starved fish. The activity of the enzymes indicative of oxidative metabolism, beta-hydroxyacyl CoA dehydrogenase (HOAD) and citrate synthase (CS), significantly increased (by 123% and 28%, respectively), and that of glucose-6-phosphate dehydrogenase (G6PDH) was inhibited by 56%. Oxidative damage under these circumstances is reversible since all biomarkers assayed returned to control values after refeeding. Our results show that prolonged starvation leads to a pro-oxidant situation and oxidative stress despite activation of antioxidant defense mechanisms, and that inhibition of G6PDH activity might be responsible for this failure in cellular antioxidant defenses.


Assuntos
Antioxidantes/metabolismo , Peixes/fisiologia , Fígado/enzimologia , Estresse Oxidativo , Inanição , 3-Hidroxiacil-CoA Desidrogenases/metabolismo , Animais , Biomarcadores/metabolismo , Catalase/metabolismo , Citrato (si)-Sintase/metabolismo , Alimentos , Glucosefosfato Desidrogenase/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Isoenzimas/metabolismo , Peroxidação de Lipídeos , Malondialdeído/análise , Superóxido Dismutase/metabolismo , Fatores de Tempo
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