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1.
W. Wieser R. Lackner S. Hinterleitner U. Platzer 《Fish physiology and biochemistry》1987,3(3):151-162
The distribution and kinetics of LDH isoenzymes in red and white muscles of 5 species of salmonids, 4 species of cyprinids and one coregonid species were studied. In all species the white muscles are characterized by the occurrence of only the most cathodic isoenzymes, or groups of isoenzymes. The red muscles contained either the full set of isoenzymes (cyprinids) or a selection in which the anodic forms dominated (salmonids, coregonid). The most striking difference between the two types of muscle was met inCoregonus sp. The temperature profiles of pyruvate affinity are similar in all species of fish studied. On the other hand, Km(pyr) values and degree of pyruvate inhibition are closely related and vary greatly with temperature, with the taxonomic position (and thus biology) of the species, and with electrophoresic mobility of the isoenzyme. Highest affinity and strongest inhibition occurred in the anodic (H4) isoenzymes of cyprinids at low temperature; lowest affinity and zero inhibition in the cathodic isoenzymes (M4 M4) of salmonids and coregonids at high temperature. In salmonids the more recently duplicated loci of the M-group of isoenzymes possess identical Km values at all temperatures, whereas the two older M and H loci differ greatly in this respect. Thus the more recent duplication of LDH loci in salmonids and coregonids may be seen as a mechanism by which the tetramers required for LDH activity can be constructed from more closely related subunits than are provided by the older M and H loci.Some problems in connection with the determination of the kinetic constants of the lactate oxidase reaction are discussed and it is suggested that an alkaline, pyruvate trapping system provides conditions which are more realistic than those of other assay systems. The Km(lactate) values found are in the biological range and, at 20°C, provide further circumstantial evidence that the red muscles of fish should be capable of oxidizing the lactate produced by the white muscles during strenuous exercise. At 4°C the Km(lactate) values are abnormally high in all muscle preparations and thus are not correlated with the Km(pyruvate) values which are lowest at this temperature. 相似文献
2.
Temperature-induced alterations in the activity of the enzyme lactate dehydrogenase (LDH) were evaluated in the freshwater
prawn Macrobrachium malcolmsonii in three groups of juveniles: controls maintained at 27±2 °C; test prawns exposed to 35 °C; test prawns exposed to 15 °C.
Changes in LDH activity and lactate levels in key tissues were assessed after 48 hrs. LDH in the skeletal muscle of the prawns
was also subjected to kinetic analysis at different temperatures. Native polyacrylamide gel electrophoresis (PAGE) analysis
and colorimetric estimation revealed decreased LDH activity (compared to controls) in the gill, heart and haemolymph, but
not in the skeletal muscle or hepatopancreas, of test prawns exposed to 15 °C; however, lactate levels were significantly
lower in all the tissues of these test prawns. Conversely, prawns exposed to 35 °C revealed elevated LDH activity in all the
tissues, barring the skeletal muscle, while lactate levels were significantly higher (compared to controls) in all the tissues
of these prawns. Kinetic analysis of LDH in the skeletal muscle at different assay temperatures revealed temperature-dependent
kinetic properties. The differences observed in LDH activity and levels of lactate in various tissues of prawns exposed to
low and high temperatures suggest aerobic and anaerobic patterns of pyruvate metabolism at respective temperatures. The results
obtained by kinetic analysis of LDH in the skeletal muscle suggest the occurrence of an adaptative response involving this
enzyme that enables M. malcolmsonii to cope with effects of thermal stress.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
3.
Ylva Lind 《Fish physiology and biochemistry》1992,9(5-6):409-415
In June, July, and September the activities of five enzymes involved in the carbohydrate and fatty acid metabolism, namely phosphofructokinase (PFK), lactate dehydrogenase (LDH), citrate synthase (CS), cytochrome oxidase (cyt ox) and 3-hydroxy-acyl-CoA dehydrogenase (HAD), were measured in the heart, liver, red muscle, white muscle, and gill lamellae of crucian carp (Carassius carassius). LDH activity was measured in both reducing (LDHr) and oxidizing (LDHo) directions.The PFK activity in red and white muscle increased significantly between July and September indicating a preparation to winter anoxia by an increased glycylytic capacity in these organs. The HAD activity of the liver had increased significantly (by more than 50%) by September, also a preparation to winter anoxia as HAD is used in the reversed -oxidation (chain elongation of fatty acids). The LDHr and cyt ox activities in the heart and white muscle were highest in July. This shows that both the anaerobic and aerobic capacities are elevated in mid-summer when water temperature is high and oxygen concentration of the water could fluctuate greatly. The LDHo and CS activities in gill lamellae were lowest in July. The results show that the metabolism of crucian carp is under seasonal influence and that a preparation to winter hypoxia/anoxia could be detected in September. 相似文献
4.
Previous studies have reported very low rates of gluconeogenesis from lactate in sea raven (Hemitripterus americanus) hepatocytes compared to other teleosts studied. This study examines whether hepatic cell redox or lactate dehydrogenase
(LDH) characteristics may explain this observation. Sea raven hepatic optimal LDH activities (pyruvate reductase direction)
were more than 40 times less compared with rainbow trout liver values (40 vs 1914 μmol·min−1·g−1 protein). The Km(lactate) was 9.24 and 0.86 mM for sea raven and trout hepatic LDH, but the Km(pyruvate) was similar between
the two species (0.11 and 0.21 mM, respectively). These results suggested that sea raven liver LDH did not favour lactate
use and was more indicative of the mammalian M-isozyme. Gel electrophoresis showed a predominant intermediate isozyme, with
a small amount of the M-type LDH. Phosphoenolpyruvate carboxykinase (PEPCK) was localized to the mitochondrial compartment,
while there was no apparent mitochondrial glutamate-oxaloacetate transaminase (GOT) activity. No in vitro lactate flux to glucose was found in untreated, 10 mM ethanol-treated, or 3 mM NH4Cl-treated sea raven hepatocytes, although CO2 production from lactate was decreased by ethanol and increased by NH4Cl. These results provide evidence that cell redox does not limit gluconeogenesis from lactate, while low activities and the
kinetic characteristics of LDH may partially explain the low lactate gluconeogenesis reported in sea raven hepatocytes.
To whom correspondence should be addressed at University of Ottawa. 相似文献
5.
Comparison of characteristics of actomyosin from white, pink, and red muscle fiber types in cultured carp 总被引：1，自引：0，他引：1
Qin Wang Mutsuyosi Tsuchimoto Osamu Yada Kyung H EE Abdul Jabarsyah Paula Andrea Gomez Apablaza Tosio Misima and Katsuyasu Tachibana 《Fisheries Science》2001,67(4):682-689
ABSTRACT: The present study compared and examined the characteristics of actomyosin among white (W), pink (P), and red (R) muscle fiber types in carp (cultured). Both the superprecipitation reaction and the Mg2+ -ATPase activity of actomyosin became higher with increased Ca2+ concentration (pCa 7.0–pCa 5.0) and with decreased adenosine triphosphate (ATP) concentration (3.0–0.5 mM) in all three muscle fiber types. A comparison of the three fiber types shows that the superprecipitation reaction of actomysoin was lower in the order of W < P < R and, in contrast, was higher for Mg2+ -ATPase activity in the order of W > P > R. A significantly positive correlation between both values was found for each of the three muscle fiber types, but these correlations were clearly different among the three muscle fiber types, and the superprecipitation reaction of actomyosin was lower in the order of W < P < R when Mg2+ -ATPase activity was at the same level. In conclusion, the characteristics of actomyosin were remarkably different among white, pink, and red muscle fiber types. 相似文献
6.
Bigeye tuna (Thunnus obesus) have much greater vertical mobility than yellowfin (T. albacares) and skipjack (Katsuwonus pelamis) tunas, due to an apparent greater tolerance of the changes in ambient temperature and oxygen occurring with depth. In an attempt to identify physiological processes (e.g., effects of temperature on cardiac function) responsible for these behavioral differences, we examined enzyme activities (at 12 °C, 17 °C, and 25 °C) of cardiac muscle in all three species. Contrary to our expectations, we found few differences and no clear explanatory patterns in maximum enzyme activities (Vmax) or enzyme activity ratios. For example, citrate synthase (CS) activity was the same in bigeye and skipjack tunas, but 40% lower in yellowfin tuna, whereas carnitine palmotoyltransferase (CPT) activity in skipjack tuna was approximately double that in the other two species. The ratio of CPT to pyruvate kinase (PK) activity, a measure of the tissues preference for fatty acids as metabolic substrates, was the same in bigeye and yellowfin tunas, but elevated skipjack tuna. The ratios of lactate dehydrogenase (LDH) to CS activity and of PK to CS activity (anaerobic–aerobic enzyme activity ratios – taken as measures of the tissues ability to tolerate hypoxia) were both elevated in yellowfin tuna cardiac tissue relative to the other two species. We also found no differences in temperature sensitivity (Q10 values) when comparing cardiac enzyme activities across species, nor effects of temperature on the substrate affinity (Km) of LDH. In sum, our results do not suggest any clear metabolic difference in the cardiac muscle that would explain the apparent greater tolerance of bigeye tuna to acute hypoxia and ambient temperature changes or their substantially greater vertical mobility. 相似文献
7.
ABSTRACT: As part of a study to clarify the differences in the temporal change in K -value among fish species, the temporal change in K -value and the 5'-inosine monophosphate (5'-IMP) and p-nitrophenol phosphate (p-NPP) degrading activities in the red, pink, and white muscle fibers in the dorsal muscle of the carp were compared. The temporal change in K -value was fastest in red, followed by pink, and white muscle fibers, at both 0°C and 32°C. Moreover, the 5'-IMP and p-NPP degrading activities were highest in red, followed by pink, and white muscle fibers at near optimum pH concentrations. The 5'-IMP degrading activity at pH 7.0 had a positive correlation with the increasing rate of K -value at 32°C for all types of muscle fibers. These results suggest that differences in increasing rates of K -values between red, pink, and white muscle fibers corresponded to the 5'-IMP degrading activities. 相似文献
8.
Protein synthesis in tissues of fed and starved carp,acclimated to different temperatures 总被引：1，自引：0，他引：1
P. W. Watt P. A. Marshall S. P. Heap P. T. Loughna G. Goldspink 《Fish physiology and biochemistry》1988,4(4):165-173
The temperature dependence of the rates of protein synthesis in the red and white skeletal muscle of the carp (Cyprinus carpio) was measured using a method which involved a single injection of tritiated phenylalanine. Plasma and muscle-free phenylalanine quickly reached a plateau level at all temperatures. During the plateau phase the incorporation of label into protein was liner. Muscle from fish previously acclimated to either a low temperature (8°C) or a high temperature (28°C), showed marked differences in the rates of protein synthesis. The results show that cold acclimation is associated with significantly higher rates of protein synthesis (p<0.001) in both red and white muscle. Arrhenius activation energies, derived from the rates of protein synthesis at the different experimental temperatures, were similar for both red and white muscle in fish acclimated to warm or cold temperatures. Measurements for both acclimated groups over the temperature range 8–34°C showed that the activation energy for the process of protein synthesis was 86.7 kJ/mol and 78.7 kJ/mol for the red and white muscle respectively. 相似文献
9.
Salmonid eggs were collected from spawning redds in the Norwegian rivers Alta, Gaula, and Driva in 1982. Their phosphoglucoisomerase (PGI; E.C. No. 5.3.1.9) patterns, as revealed by isoelectric focusing and histochemical staining, were compared to standard zymograms produced by Atlantic salmon (Salmo salar L.) and trout (S. trutta L.) white skeletal muscle extracts, and to the zymogram in salmon eggs of known origin. In salmon, the egg zymogram was identical with that of muscle. Two types of zymograms, identical with either salmon or trout muscle zymograms and thus regarded as species-determinants, were observed among the eggs from wild fish. Their proportions in the three rivers were as expected from current knowledge of species composition. The present findings are related to previous reports on PGI expression in salmonids. The PGI zymograms are probably diagnostic keys to species for eggs from Norwegian stream-dwelling salmonids, including Arctic char (Salvelinus alpinus L.). Some managemental implications of the present results are briefly discussed. 相似文献
10.
Red and white muscle from specimens of wild and farmed gilthead sea bream (Sparus aurata) were analyzed for histochemical ATPase activity, total protein content, fatty acids, trace element concentrations and myosin isoforms. The fibre type composition of muscle samples was confirmed histochemically by the ATPase reaction, which did not show any differences between the two groups of animals. Myosin ATPase activities, myosin and protein yields were significantly higher in white muscle than in the red muscle and for the red muscle the latter two parameters were higher in wild fish. Fatty acid profiles revealed differences between the two groups of animals, probably because of the fatty acid composition of the diets. Zinc, copper and iron concentrations were higher in red muscle than in white muscle; muscles from wild fish were significantly richer in trace elements. No separation of fast and slow heavy chains of myosin could be obtained on SDS-gel electrophoresis, but two dimensional electrophoresis revealed the presence of three light chains in white muscle (LC1F, LC2F, LC3F), and two main types in red muscle (LC1S, LC2S). Small, variable percentages of LC3F were found in the red muscle samples, especially in the wild fish. It is concluded that the different environmental conditions, experienced by wild and farmed fish, have significantly influenced the biochemical composition of their lateral muscle. 相似文献
11.
Antarctic fish of the family Channichthyidae (Icefishes) lack the respiratory pigments haemoglobin and myoglobin. The morphometrics and ultrastructure of the ventricular myocardium of a benthic icefish,Chaenocephalus aceratus has been compared with that of a red-blooded Notothenioid fish,Notothenia neglecta, of similar habit.The mass of ventricular muscle as a percentage of bodyweight is 3 times greater in adultC. aceratus (0.32%) thanN. neglecta (0.11%). Myoglobin concentration in the ventricle ofN. neglecta, 20 nmoles/g, is comparable to that of temperate teleosts with similar activity patterns. The volume and surface densities of mitochondria are 41.5% and 0.32 m–1 for Icefish and 25% and 0.15 m–1 forN. neglecta, Cytochrome oxidase activities are similar in the two tissues whilst the volume density of myofibrils is higher forN. neglecta (47%) thanC. aceratus (29.9%).The proliferation of mitochondria in the myocardium of Icefish will reduce the diffusion path-length for oxygen between ventricular lumen and the outer mitochondrial membrane and may compensate for the absence of myoglobin. 相似文献
12.
达里湖和岗根湖东北雅罗鱼和鲫四种同工酶的比较研究 总被引：3，自引：0，他引：3
比较了达里湖和岗根湖的东北雅罗鱼(Leuciscus waleckii)和鲫(Carassius auratus)肌肉、肝脏、心肌组织中过氧化物酶(POD)、酯酶(EST)、乳酸脱氢酶(LDH)、苹果酸脱氢酶(MDH)的差异。结果显示:达里湖中东北雅罗鱼和鲫在心脏和肝脏中POD、EST含量均高于岗根湖,而肌肉中含量相对低些;MDH、LDH在三种组织中的含量达里湖中的东北雅罗鱼和鲫也高于岗根湖。由试验结果可知,东北雅罗鱼和鲫心肌和肝脏中四种同工酶的含量高于岗根湖,肌肉中四种同工酶的含量相对稳定。 相似文献
13.
魁蚶血细胞分类及其免疫功能的初步分析 总被引：4，自引：2，他引：2
借助显微观察和鳗弧菌免疫刺激等手段,首次对魁蚶血细胞进行分类及免疫功能分析.魁蚶血细胞可分为3大类:红细胞、白细胞和血栓细胞,红细胞发育过程大致经历新生、成熟、衰老和死亡4个阶段.白细胞分为:嗜酸性、嗜中性、嗜碱性细胞,以及淋巴细胞和巨核细胞.嗜酸性、嗜中性、嗜碱性细胞和血栓细胞均参与血液的凝固;红细胞、白细胞均有吞噬病原菌能力,红细胞具有被动吞噬作用和免疫吸附作用,白细胞具有主动吞噬作用,嗜酸性和嗜中性细胞是吞噬病原菌的主体,嗜碱性细胞具有吞噬大颗粒异物的作用,魁蚶感染病原菌后白细胞增多并表现炎症.研究表明,魁蚶血细胞在应对外界的免疫刺激时,能作出系统免疫应答,且血细胞免疫分工明确,以抵御外界不良刺激. 相似文献
14.
Spawning induces a shift in energy metabolism from glucose to lipid in rainbow trout white muscle 总被引：1，自引：0，他引：1
A. Kiessling L. Larsson K. -H. Kiessling P. B. Lutes T. Storebakken S. S. S. Hung 《Fish physiology and biochemistry》1995,14(6):439-448
Enzymatic changes that occur in the white somatic muscle of rainbow trout (Oncorhynchus mykiss) in response to spawning were investigated, and the evenness of their distribution across the ventral-dorsal plane of this muscle was assessed. Four enzymes that are involved in energy metabolism were measured (phosphofructokinase: glycolytic capacity, 3-hydroxyacyl-CoA dehydrogenase: -oxidation, citrate synthase: citric acid cycle, cytochrome oxidase: oxidative capacity). The enzyme activities were followed in different parts of the white muscle of non-spawning female rainbow trout from May, four months after their first spawning, until December, at second spawning. Samples were taken from white epaxial muscle along the lateral line, on the dorsum, and in between. Samples were also taken from red muscle of non-spawning fish. The isoforms of myosin heavy chains (MyHC) were electrophoretically identified on 6% SDS-PAGE gel to study possible changes in contractile properties of the muscle.Transformation from the non-spawning to spawning phase was associated with dramatic changes in the activity of the enzymes studied in white muscle: glycolytic capacity decreased to less than half, whereas oxidative metabolism increased about two- to four-fold in all areas. Significant quantitative differences in enzyme activities were found between the three epaxial muscle areas: in the non-spawning fish lateral line samples differed from those taken in the other two areas, whereas in spawning fish the dorsal sample difered from the other two. No difference in the expression of MyHC-isoforms was found between spawning and non-spawning fish. Co-expression of both slow and fast isoforms was found in single fibres isolated from red muscle.The results show that the energy metabolism in white muscle of domestic rainbow trout is altered during spawning; i.e., the metabolism becomes increasingly aerobic, with an increased capacity for fatty acid utilization, concomitant with phenotypic changes associated with sexual maturation. These changes are especially pronounced in ventral, superficially located fibres. 相似文献
15.
Alaa G. M. Osman Imam A. Mekkawy Johan Verreth Frank Kirschbaum 《Fish physiology and biochemistry》2007,33(1):1-13
Glucose-6-phosphate dehydrogenase (G6PDH), lactate dehydrogenase (LDH) and pyruvate kinase (PK) are key metabolic enzymes.
G6PDH has been used as a biomarker of pollution-induced carcinogenesis in fish. LDH has been used as marker of lesions in
toxicology and clinical chemistry, and PK catalyses the conversion of phosphoenol pyruvate to pyruvate, with regeneration
of ATP. The effect of different concentrations of lead nitrate on the activity of these enzymes in two different early ontogenetic
stages (embryonic and free embryonic stage) of the African catfish Clarias gariepinus was investigated. Embryo homogenates were used for measurements of G6PDH, LDH and PK activity spectrophotometrically at 340 nm
and 25°C. The ontogenetic variations of the three enzymes during early ontogeny, from the 30 h to the 168 h post-fertilisation
stage (PFS) (beginning of exogenous feeding), were studied. There was a significant decrease in activities of all three enzymes
from 30 h-PFS to 96 h-PFS, followed by a significant increase in G6PDH and LDH. PK showed insignificant fluctuations in activity.
Different patterns of enzyme activities were recorded due to exposure to different lead nitrate concentrations (100 μg/l,
300 μg/l and 500 μg/l). In the pre-hatching stage (30 h-PFS) the activity of the three enzymes increased at exposure to 100 μg/l
lead nitrate and then decreased with increasing dose. In the post-hatching stages (48 h-PFS–168 h-PFS) G6PDH activity increased
and LDH activity decreased with increasing lead concentrations. Unlike G6PDH and LDH, the PK enzyme fluctuated during the
post-hatching stages and did not reveal a specific trend of response (increase or decrease) with increasing lead concentrations.
Therefore, the measurement of G6PDH and LDH activities, but not PK activity, could be useful biomarkers of intoxication to
reveal the embryotoxic potential of lead nitrate in fish embryos. The post-hatching stages of the African catfish are more
sensitive than the pre-hatching stage (30 h-PFS) is, probably due to the protective capacity provided by the hardened chorion.
The interaction and the main effects of age and lead doses were found to be highly significant, referring to the great impact
of lead on these enzyme systems with increasing early development. 相似文献
16.
In order to investigate the capacities of different tissues to oxidize fatty acids, total β-oxidation (mitochondrial and peroxisomal) of [1–14 C]palmitoyl-CoA was determined in liver and red- and white muscle from adult and juvenile Atlantic salmon Salmo salar. By including potassium cyanide (KCN) in the assay medium, it was possible to differentiate between mitochondrial and peroxisomal β-oxidation capacities. Mitochondrial β-oxidation dominated in all tissues except in livers from juvenile fish where the peroxisomal β-oxidation dominated. In general, the red muscle possesses the highest fatty acid oxidation capacity, however, by taking into consideration the fact that white muscle occupies approximately 60% of the total body weight, this study demonstrates that the white muscle is an important tissue in the overall fatty acid catabolism. 相似文献
17.
This study examined how muscle metabolic organization varied during an annual cycle in which rainbow trout (Oncorhynchus mykiss) were held in outdoor holding ponds in which they were exposed to natural changes in temperature (range 0.2 to 15.6°C) and
photoperiod. We examined the activities of glycolytic and mitochondrial enzymes in red and white muscle to evaluate whether
trout enhance their capacity for lipid and carbohydrate oxidation during cold-acclimization. When assayed at habitat temperature,
the enzyme activities generally increased in spring to reach a maximum in summer followed by a decrease in the fall. This
led to significantly higher activities at warm than cold periods for all enzymes measured in red muscle and all but one in
white muscle. The activities at 10°C provided little evidence for compensatory adjustments of aerobic capacity. Particularly
in red muscle, enzyme levels at 10°C were generally lower during cold than warm periods. The variation of enzyme activities
throughout the cycle was not due to changes in protein concentration, as the same responses were observed when activities
were expressed per g wet mass or per mg protein. Although the aerobic capacity did not increase with cold-acclimatization,
the relative capacity for lipid oxidation was higher in winter than in summer trout. In contrast, the relative capacity for
aerobic glycolysis was higher in summer than in winter trout. Thus, the metabolic capacities of trout muscle undergo seasonal
reorganization. 相似文献
18.
采用不连续聚丙烯酰胺凝胶电泳技术对雅鲁藏布江中游6种裂腹鱼(尖裸鲤Oxygymnocypris stewartii、拉萨裸裂尻鱼Schizopygopsis younghusbandi、巨须裂腹鱼Schizothorax macropogon、拉萨裂腹鱼S.waltoni、双须叶须鱼Ptychobarbus dipogon和异齿裂腹鱼S.o'connori)的心肌、肌肉、肝脏、肾脏和晶状体5种组织的LDH(乳酸脱氢酶)同工酶进行比较分析。结果表明LDH同工酶的表达具有明显的组织和种间差异性。尖裸鲤、拉萨裸裂尻鱼和双须叶须鱼由LDH-A、LDH-B和LDH-B1基因编码,5种组织中分别检测到16、13和9条酶带;拉萨裂腹鱼和巨须裂腹鱼由LDH-A、LDH-B和LDH-C基因编码,5种组织中分别检测到9和6条酶带;异齿裂腹鱼由LDH-A和LDH-B基因编码,5种组织中检测到6条酶带。根据酶谱特征对其生物演化进行了探讨,发现尖裸鲤和拉萨裸裂尻鱼特化程度最高,其次是双须叶须鱼,巨须裂腹鱼、拉萨裂腹鱼和异齿裂腹鱼特化程度最低,与形态学特征所划分的三个类群吻合。 相似文献
19.
Nicholas P. L. Tuckey Gerard J. A. Janssen Malcolm E. Forster Steven P. Gieseg 《Journal Of Aquatic Food Product Technology》2013,22(2):156-167
Perfusion of fish tissues may provide a model for manipulating their properties post-harvest. Perfusion of Chinook salmon (Oncorhynchus tshawytscha) tails in vitro with oxygenated physiological saline at 5°C showed delivery to the muscle was at the ratio of 5.8:1 red:white muscle, respectively. Treatment with sodium nitroprusside (a nitric oxide donor) did not improve delivery to the white muscle. Perfusion at 15°C with and without ascorbic and uric acids showed that the inclusion of antioxidants reduced protein oxidation but did not reduce lipid peroxidation in the red muscle. This technique, with further development, shows potential as a post-mortem research tool. 相似文献
20.
Juvenile matrinxã, Brycon cephalus, were submitted to sustained swimming for 72 days at 1.0 body length s?1. Exercised fish (EF) grew more than non‐EF and their feed conversion ratio (FCR) improved; haematological responses demonstrated a decrease in haemoglobin and mean cell haemoglobin contents and increase in the mean cell volume. In the plasma, sodium, ammonia and amino acid concentrations increased; plasma triglycerides decreased while free fatty acids increased. Liver glucose, free amino acids, ammonia, the rate protein per fish weight and total lipid content increased, while the glycogen per fish ratio declined. Glutamate dehydrogenase (GDH) activity increased while pyruvate kinase (PK) and lactate dehydrogenase (LDH) decreased. White muscle glucose, lactate, the glycogen per fish‐weight ratio and total lipid content exhibited a decrease in their values; ammonia, free amino acids and the protein per fish‐weight ratio increased. GDH and PK decreased their activities. In the red muscle glycogen store, the glycogen per fish‐weight ratio and glucose were reduced. Juvenile matrinxãs, under sustained swimming, were physiologically and biochemically adapted to exercise as indicated by improved blood flow, transport and oxygen uptake, FCR, amino acid and protein incorporation and growth. Continuous exercise is a good practice for B. cephalus cultivation. 相似文献