glycogen and Fish-Diseases

Blunt snout bream (Megalobrama amblycephala) were randomly assigned into three diets: normal-carbohydrate diet (NCD, 30% carbohydrate, w/w), high-carbohydrate diet (HCD, 43% carbohydrate), and HCB (HCD supplemented with 50 mg/kg berberine (BBR)). After 10 weeks' feeding trial, the results showed that higher levels of plasma glucose, triglyceride, and total cholesterol were observed in HCD-fed fish than in NCD-fed fish, while HCB feeding significantly ameliorated this effect. Moreover, HCB feeding remarkably reversed HCD-induced hepatic glycogen and lipid contents. In insulin signaling, BBR inclusion restored HCD-induced suppression of insulin receptor substrate mRNA expression and elevation of forkhead transcription factor 1 mRNA expression. In glucose metabolism, upregulated glucose transporter 2 and glycogen synthase mRNA expressions in the HCD group were observed compared to the NCD group. However, BBR adding reduced the mRNA expressions of glycogen synthase, phosphoenolpyruvate carboxykinase, and glucose-6-phosphatase and increased the transcriptional levels of glucose transporter 2 and pyruvate kinase. In lipid metabolism, BBR supplementation could reverse downregulated hepatic carnitine palmitoyl transferase I mRNA expression and upregulated hepatic acetyl-CoA carboxylase and fatty acid synthetase mRNA expressions in the HCD group. Taken together, it demonstrates that BBR could improve glucose metabolism of this species via enhancing liver's glycolysis and insulin signaling, while inhibiting liver's glycogen synthesis and gluconeogenesis. It also indicates that BBR could reduce the metabolic burden of the liver by inhibiting fat synthesis and promoting lipid decomposition, and then enhance fat uptake in peripheral tissues.

Topics: Animal Feed; Animals; Azo Compounds; Berberine; Diet; Dietary Carbohydrates; Dietary Supplements; Fish Diseases; Fishes; Gene Expression Regulation; Glucose; Glycogen; Lipid Metabolism; Lipids; Liver

Aloe vera is a traditional medicinal plant; however, its use in fish is fairly recent. We evaluated the effects of dietary A. vera on stress, innate immunity, and energy metabolism in pacu inoculated with Aeromonas hydrophila. For 7 days, 192 fish were fed with diets supplemented with 0% (control), 0.5%, 1.0%, and 2.0% of the plant extract and then inoculated with bacteria and sampled 3, 6, and 24 h later. All concentrations of A. vera reduced basal levels of cortisol, and 1.0% reduced cortisol levels more intensely 3 h after inoculation. A. vera increased the basal respiratory activity of leukocytes/RAL (0.5 and 1.0%), increased the serum levels of lysozyme (1.0 and 2.0%) 6 h after inoculation, and increased the activity of the complement system after 3 h. Spleen somatic index/SSI increased with 1.0 and 2.0% A. vera. A. vera also promoted metabolic effects. It increased basal levels of lipids in the liver and muscle, as well as hepatosomatic index (1.0%) and, 3 h after inoculation, prevented the reduction of serum triglyceride (1.0%) and reduced the mesenteric fat (1.0%). Bacterial inoculation increased RAL from 3 to 24 h and lysozyme levels at 24 h, increased serum cholesterol at 24 h, and decreased serum triglyceride from 3 to 24 h, regardless of A. vera. We concluded that A. vera offered for only 7 days had stress-reducing effects, stimulated innate immunity, protected triglyceride levels in blood, lipid depots in the liver and muscle, and directed the energy mobilization to visceral depots.

Topics: Aeromonas hydrophila; Aloe; Animals; Blood Glucose; Characiformes; Cholesterol; Energy Metabolism; Fish Diseases; Glycogen; Gram-Negative Bacterial Infections; Hydrocortisone; Immunity, Innate; Leukocytes; Lipids; Liver; Muramidase; Muscles; Plant Extracts; Random Allocation; Reactive Oxygen Species; Stress, Physiological; Triglycerides

Fish metabolic allostatic dynamics, when animal present physiological modifications that can be strategies to survive, are important for promoting changes to ensure whole body self-protection and survival in chronic states of stress. To determine the impact of sequential stressors on pacu (Piaractus mesopotamicus), fish were subjected to two trials of stressful treatments, administration of exogenous dietary cortisol, and parasite challenge. The first experiment consisted of a two-day acute stress trial and the second, an eight-day chronic stress trial, and after both experiments, fish parasite susceptibility was assessed with the ectoparasite Dolops carvalhoi challenge. Physiological changes in response to acute trial were observed in glycogen, cortisol, glucose, osmolarity, sodium, calcium, chloride, potassium, hematocrit, hemoglobin, red blood cells and mean corpuscular volume, and white blood cell (P < 0.05), whereas response to chronic trial were observed in glycogen, osmolarity, potassium, calcium, chloride, mean corpuscular volume, white blood cell, neutrophil, and lymphocyte (P < 0.05). Acute trials caused physiological changes, however those changes did not induce the consumption of hepatic glycogen. Chronic stress caused physiological changes that induced hepatic glycogen consumption. Under acute trial, stress experience was important to fish to achieve homeostasis after chronic stress. Changes were important to modulate the response to stressor, improve body health status, and overcome the extra stressor with D. carvalhoi challenge. The experiments demonstrate that pacu initiate strategic self-protective metabolic dynamics in acute states of stress that ensure the maintenance of important life processes in front of sequential stressors.

Topics: Allostasis; Animals; Arguloida; Characiformes; Diet; Ectoparasitic Infestations; Fish Diseases; Fisheries; Glycogen; Hematocrit; Hemoglobins; Hydrocortisone; Lymphocyte Count; Neutrophils; Osmolar Concentration; Potassium; Random Allocation; Stress, Physiological; Time Factors

Spermiogenesis in progenetic and adult stages of Archigetes sieboldi Leuckart, 1878, a tapeworm parasitic in oligochaetes and fish respectively, has been examined using transmission electron microscopy and cytochemical staining for glycogen. General pattern of spermiogenesis is essentially like that of other caryophyllideans, i.e., apical dense material in the zone of differentiation in the early stages of spermiogenesis, rotation of free flagellum and a flagellar bud, and proximo-distal fusion. Interestingly, rotation of a free flagellum and flagellar bud to the median cytoplasmic process (MCP) has been observed unconventionally at > 90° only in progenetic stages. Typical striated roots associated with the centrioles occur rarely in A. sieboldi, and only in form of faint structures in advanced stages of spermiogenesis. In contrast to most caryophyllideans studied to date, penetration of the nucleus into the spermatid body has started before the fusion of the free flagellum with the MCP. This feature has been reported rarely but exclusively in the family Caryophyllaeidae. The unipartite mature spermatozoon of A. sieboldi is composed of one axoneme of the 9 + '1' trepaxonematan pattern with its centriole, parallel nucleus, and parallel cortical microtubules which are situated in a moderately electron-dense cytoplasm with glycogen particles. An unusual arrangement of cortical microtubules in the two parallel rows in region I of the spermatozoon is described here for the first time in the Caryophyllidea. Ultrastructural data on spermiogenesis and the spermatozoon in A. sieboldi from tubuficids and carp are compared and discussed with those in other caryophyllideans and/or Neodermata.

Topics: Animals; Axoneme; Carps; Cell Nucleus; Cestoda; Cestode Infections; Fish Diseases; Flagella; Glycogen; Male; Microscopy, Electron, Transmission; Spermatids; Spermatogenesis; Staining and Labeling

In the present study, the hybrid grouper (Epinephelus fuscoguttatus ♀ × E. lanceolatus ♂), a typical carnivorous fish, was chosen as a model to investigate the regulation of glycogen metabolism owning to its characteristic of glucose intolerance. The variation of plasma glucose concentration, glycogen content, and expressions of glycogen metabolism-related genes under acute hyperglycemia stress were measured. Following glucose administration, plasma glucose concentration increased immediately, and the glucose level remained elevated for at least 12 h. The prolonged glucose clearance and hyperglycemia revealed glucose intolerance of this fish species. Meanwhile, the glycogen content in both liver and muscle changed significantly during the clearance of plasma glucose. However, the peak value of hepatic glycogen (1 and 12 h post injection) appeared much earlier than muscle (3 and 24 h post injection). To investigate the regulation of glycogen metabolism from molecular aspect, the complete coding sequence (CDS) of glycogen synthase (GS) and glycogen phosphorylase (GP) in both liver and muscle types were obtained, encoding a polypeptide of 704, 711, 853, and 842 amino acid residues, respectively. The results of gene expression analysis revealed that the expression of liver type and muscle type GS was significantly higher than other time points at 12 and 24 h post glucose injection, respectively. Meanwhile, the highest expressions of GP in both liver and muscle types occurred at 24 h post glucose injection. The response of GS and GP to glucose load may account for the variation of glycogen content at the transcriptional level to some extent.

Topics: Animals; Bass; Blood Glucose; Fish Diseases; Glycogen; Glycogen Synthase; Hyperglycemia; Phosphorylases; Stress, Physiological

The acanthocephalan parasite Acanthocephalus dirus infects the freshwater isopod Caecidotea intermedius as an intermediate host before completing its life cycle in a fish. Transmission to the definitive host occurs after the parasite has reached the cystacanth stage, and development into this stage is associated with changes in several behavioral and physiological traits of the host. Given the potential importance of host energy availability to trait modification, we examined the relationship between cystacanth-stage infection and energy storage of adult isopods. Six samples of infected and uninfected male C. intermedius were collected from a population in March, April, and May during which time cystacanth-stage A. dirus dominate infections and modification of behavior and physiology occurs in nature. Biochemical assays revealed that infected male C. intermedius contained more glycogen and more lipid than uninfected males and that this difference was present throughout the sampling period, which represents the entire adult phase of the host's life. Additional analysis revealed that infected and uninfected males differed in their pattern of allocation to each energy source and that host lipid levels were negatively correlated with parasite intensity. We propose that the typical pattern of allocation and storage of host energy appears to be disrupted by A. dirus infection and that the changes are more likely to favor the parasite than the host.

Topics: Acanthocephala; Animals; Energy Metabolism; Fish Diseases; Fishes; Fresh Water; Glycogen; Helminthiasis, Animal; Host-Parasite Interactions; Isopoda; Life Cycle Stages; Lipid Metabolism; Male

Cyanobacterial blooms threaten human health as well as the population of other living organisms in the aquatic environment, particularly due to the production of natural toxic components, the cyanotoxin. So far, the most studied cyanotoxins are microcystins (MCs). In this study, the hepatic alterations at histological, proteome and transcriptome levels were evaluated in female and male medaka fish chronically exposed to 1 and 5 μg L

Topics: Animals; Bacterial Toxins; Cell Extracts; Chemical and Drug Induced Liver Injury; Circadian Rhythm; Down-Regulation; Female; Fish Diseases; Glycogen; Lipid Metabolism; Liver; Male; Microcystins; Microcystis; Oryzias; Oviparity; Protein Biosynthesis; Proteome; Reproduction; Transcriptome

Dietary compromises, especially food restrictions, possess species-specific effects on the health status and infection control in several organisms, including fish. To understand the starvation-mediated physiological responses in Edwardsiella tarda infected red sea bream, especially in the liver, we performed a 20-day starvation experiment using 4 treatment (2 fed and 2 starved) groups, namely, fed-placebo, starved-placebo, fed-infected, and starved-infected, wherein bacterial exposure was done on the 11th day. In the present study, the starved groups showed reduced hepatosomatic index and drastic depletion in glycogen storage and vacuole formation. The fed-infected fish showed significant (P<0.05) increase in catalase and superoxide dismutase activity in relation to its starved equivalent. Significant (P<0.05) alteration in glucose and energy metabolism, as evident from hexokinase and glucose-6-phosphate dehydrogenase activity, was recorded in the starved groups. Interestingly, coinciding with the liver histology, PPAR (peroxisome proliferator activated receptors) α transcription followed a time-dependent activation in starved groups while PPARγ exhibited an opposite pattern. The transcription of hepcidin 1 and transferrin, initially increased in 0dai (days after infection) starved fish but reduced significantly (P<0.05) at later stages. Two-color immunohistochemistry and subsequent cell counting showed significant increase in P63-positive cells at 0dai and 5dai but later reduced slightly at 10dai. Similar results were also obtained in the lysosomal (cathepsin D) and non-lysosomal (ubiquitin) gene transcription level. All together, our data suggest that starvation exerts multidirectional responses, which allows for better physiological adaptations during any infectious period, in red sea bream.

Topics: Animals; Catalase; Edwardsiella tarda; Energy Metabolism; Enterobacteriaceae Infections; Fish Diseases; Fish Proteins; Food; Gene Expression; Glucose; Glycogen; Host-Pathogen Interactions; Liver; PPAR alpha; PPAR gamma; Reverse Transcriptase Polymerase Chain Reaction; Sea Bream; Starvation; Superoxide Dismutase; Vacuoles

Topics: Adrenal Gland Neoplasms; Animals; Carcinoma, Hepatocellular; Cell Nucleus; Cyprinidae; Female; Fish Diseases; Glycogen; Hepatocytes; Liver Neoplasms; Pheochromocytoma

The need to expand aquaculture production has led to other fish to be considered as potential species for culture, such as the sub-Antarctic notothenioid Eleginops maclovinus (Valenciennes, 1830). The aim of this study was to determine the cumulative effect of density and pathogen infection by protein extract of Piscirickettsia salmonis on skeletal muscle metabolism. In a first experiment, specimens were submitted to three different stocking densities: (1) 3.1 kg m(-3), (2) 15 kg m(-3) and (3) 60 kg m(-3), for a period of 10 days. In a second experiment, metabolic changes caused by an infection of P. salmonis protein extract (a single injection of 0.5 μL P. salmonis protein extract g body weight(-1) was inoculated in the fish) and its combined effect with stocking density was assessed during a period of 10 days. This study concludes that stress caused by high stocking density led to the reorganization of some metabolic routes to fulfill skeletal muscle energy needs. Furthermore, infection response by pathogen P. salmonis differed when stocking density increased, suggesting an increase of energy needs with density in skeletal muscle of infected fish.

Topics: Amino Acids; Animal Husbandry; Animals; Aquaculture; Fish Diseases; Gene Expression Regulation; Glucose; Glycogen; Muscle Proteins; Muscle, Skeletal; Perciformes; Piscirickettsia; Piscirickettsiaceae Infections; Risk Factors

Vitellogenesis in the caryophyllidean tapeworm Archigetes sieboldi Leuckart, 1878, from carp Cyprinus carpio L. in Slovakia, has been examined using transmission electron microscopy and cytochemical staining with periodic acid-thiosemicarbazide-silver proteinate (PA-TSC-SP) for glycogen. Vitelline follicles extend in two lateral bands in the medullary parenchyma along both sides of the monozoic body. They are surrounded by an external basal lamina and contain vitellocytes and an interstitial tissue. The general pattern of vitellogenesis is essentially like that of other caryophyllideans. It involves four stages: immature, early maturing, advanced maturing cells and mature vitellocytes. During vitellogenesis, a continuous increase in cell volume is accompanied by an extensive development of cell components engaged in shell globule formation, e.g. granular endoplasmic reticulum and Golgi. Shell globule clusters are membrane-bound. Nuclear and nucleolar transformation are associated with formation and storage of large amounts of intranuclear glycogen, a very specific feature of the Caryophyllidea. For the first time, (a) additional vitelline material in Archigetes is represented by lamellar bodies and (b) lipid droplets are described in the mature vitellocytes from vitelline follicles and vitelloduct of the Caryophyllidea. Our results indicate that there may be a double origin of lamellar bodies: either from the endoplasmic reticulum or through transformation of shell globule/shell globule clusters. Lamellar body clusters and some single lamellar bodies appear to have a membrane. Other ultrastructural features of vitellogenesis and/or vitellocyte in A. sieboldi from its vertebrate (fish) and invertebrate (oligochaete) hosts are briefly compared and contrasted with those in other caryophyllideans and/or Neodermata.

Topics: Animals; Carps; Cell Differentiation; Cestoda; Cestode Infections; Cytoplasmic Structures; Female; Fish Diseases; Glycogen; Intestinal Diseases, Parasitic; Lipid Metabolism; Microscopy, Electron, Transmission; Ovarian Follicle; Vitellogenesis

The vitellogenesis of Paraechinophallus japonicus (Yamaguti, 1934), the first pseudophyllidean tapeworm of the family Echinophallidae studied using transmission electron microscope, is described on the basis of ultrastructural observations of specimens from the benthopelagic fish Psenopsis anomala (Temminck et Schlegel, 1844) (Perciformes: Centrolophidae). The process of vitellogenesis in P. japonicus follows the same general pattern observed in other tapeworms. Five stages of vitellocyte development have been distinguished. The first stage corresponds to immature cells containing ribosomes and mitochondria. The second stage of development is characterized by the appearance of granular endoplasmic reticulum and Golgi complexes, formation of shell globules and lipid droplets at the periphery of the cell cytoplasm. Vitellocyte of the third stage presents accumulation of shell globules and lipid droplets. During the fourth stage, shell globule clusters are formed, and lipid droplets and rosettes of alpha-glycogen are accumulated. Mature vitelline cells are characterized by a great number of lipid droplets with glycogen in the centre of the cytoplasm, whereas shell globule clusters are situated more peripherally. The interstitial tissue of vitelline follicles of P. japonicus is syncytial with long cytoplasmic projections extending between vitelline cells. The presence of a large amount of lipid droplets in the vitelline cytoplasm within the eggs of P. japonicus may be related to egg accumulation in the uterine sac.

Topics: Animals; Cestoda; Cestode Infections; Female; Fish Diseases; Glycogen; Histocytochemistry; Lipids; Microscopy, Electron, Transmission; Ovum; Perciformes; Vitelline Membrane; Vitellogenesis

The ultrastructural image of glycogen granules in the cytoplasm of rainbow trout phagocytes in sections stained by the conventional lead or uranyl-lead stains is highly dependent on fixation conditions, the granules being visible only when adequate fixation protocols are used. Morphometry of samples processed for the detection of peroxidase or esterase activities (to specifically label neutrophils and macrophages, respectively), and simultaneously stained for the specific detection of glycogen, showed that inflammatory peritoneal neutrophils were richer in glycogen granules than resting neutrophils. This increase in glycogen content occurs after the migration from the haematopoietic tissues and peripheral blood to the inflamed foci. Glycogen granules could not be found in resting peritoneal macrophages but were found in inflammatory macrophages. The macrophage granules occurred in smaller amounts than in neutrophils, and consisted of granules identical to those of neutrophils together with significantly smaller granules. No evidence for the utilization of glycogen by neutrophils phagocytosing bacteria within the peritoneal cavity was found.

Topics: Animals; Aquaculture; Blood Glucose; Cytoplasmic Granules; Fish Diseases; Glycogen; Inflammation; Macrophages, Peritoneal; Neutrophils; Oncorhynchus mykiss; Phagocytes; Yersinia; Yersinia Infections

To study the direct cause of liver enlargement in the Japanese flounder Paralichthys olivaceus infected with Edwardsiella tarda, the fish were challenged with E. tarda and reared without feeding. The liver of fish exposed to the bacteria was markedly enlarged compared to that of the controls while no severe histopathological change appeared in the organ during the experiments. No notable difference was observed in the crude fat, glycogen, and water content of the liver between challenged and control fish. The size of liver cells and nuclei of the challenged fish was apparently larger than that of the controls. Analysis of crude DNA in the liver suggested that the number of liver cells of starved control fish significantly decreased during the experiment while that of the challenged fish was maintained at a level of the initial control. RNA/DNA ratio of the liver of challenged fish clearly increased while it decreased in the control fish during the experiment. These observations suggest that liver enlargement of flounder infected with E. tarda, at least in the early stage of infection, is not a result of any readily observable histopathological changes and that E. tarda infection causes hypertrophy of the cells, as well as preventing decrease in liver cell number.

Topics: Animals; Blood Glucose; DNA, Bacterial; Edwardsiella tarda; Electrophoresis, Polyacrylamide Gel; Enterobacteriaceae Infections; Fish Diseases; Flatfishes; Glycogen; Hypertrophy; Image Processing, Computer-Assisted; Kidney; Liver; Organ Size; RNA, Bacterial; Seawater; Water

The high ion-exchange capacity of zeolite (sodium aluminium silicate) enhances the removal of lead from water, thus decreasing its availability to fish. Zeolites are very important in the field of environmental preservation due to the low cost and ecological compatibility. Zeolites can adsorb metallic ions by cation exchange reactions. Continuous exposure of the teleost fish Heteropneustes fossilis to sublethal concentrations of lead nitrate in water solution for short (35 days) and long (120 days) periods decreased both the soluble protein, RNA and glycogen contents in the liver and the body weight, but increased the cholesterol content. The presence of zeolite in the exposure solution decreased all of the adverse effects. In fish exposed to zeolite as feed additive, all the parameters improved in comparison to control fish, indicating that zeolites can be used safely in biological systems.

Topics: Adsorption; Animals; Catfishes; Fish Diseases; Glycogen; Lead; Liver; Nitrates; Proteins; RNA; Zeolites

We postulate that ocular abnormalities in farmed Atlantic halibut occur following aberrant gas production in the choroidal body associated with the enzyme carbonic anhydrase. We investigated choroidal body carbonic anhydrase activity in affected and normal halibut. Immunohistochemical detection of carbonic anhydrase allowed neither quantification of enzyme levels nor determination of enzyme activity. Histochemical detection of carbonic anhydrase, however, allowed microdensitometric quantification of enzyme activity. Mean enzyme activity in affected individuals was over twice that in normal fish. Glycogen, which we suggest is used to fuel oxygen production in the choroidal body, was evaluated by Best's carmine staining. Microdensitometry demonstrated glycogen levels of be significantly higher in affected fish. These findings show that posterior segment gas bubble and cyst formation is associated with aberrantly high choroidal enzyme activity and high choroidal glycogen concentrations.

Topics: Animals; Carbonic Anhydrases; Choroid; Choroid Diseases; Fish Diseases; Fisheries; Flatfishes; Glycogen; Immunohistochemistry

The present study describes light and electron microscopic changes in the liver of Atlantic salmon during the development of infectious salmon anemia (ISA). Atlantic salmon postsmolts weighing 80-100 g were infected by intraperitoneal injections, and liver samples were collected sequentially between day 0 and day 25 post infection (p.i.), with time intervals of 3-4 days. At each collection time, livers from five infected fish and two control fish were examined. Changes involving the perisinusoidal macrophages were observed by transmission electron microscopy, from day 4 p.i. Large vacuoles, containing a fine-granular material with low electron density, accumulated in the cytoplasm. These changes persisted and became more severe throughout the investigation, leading to a considerable increase in the size of the cells. At day 14 p.i., degenerative features of the sinusoidal endothelium were observed. By day 18 p.i., areas of the liver were devoid of a sinusoidal endothelial lining, bringing hepatocytes in direct contact with blood cells. At this stage, the sinusoids were moderately congested. From day 21 p.i., heavy sinusoidal congestion, peliosis hepatis, and degeneration of the hepatocytes were observed. No virus was observed in any of the inhabitant cell types of the liver. Gross and light microscopic changes were first recorded at day 18 p.i., as was a significant decrease in the hematocrit values. By day 25 p.i., characteristic multifocal, confluent, hemorrhagic necroses were present. Results of the present investigation suggest that the liver lesions observed with ISA are not the result of the development of an anemia alone or caused by direct viral damage to hepatocytes. Hepatocellular degeneration succeeded changes in the perisinusoidal macrophages and degeneration of the sinusoidal endothelium. These changes may have impeded the sinusoidal blood flow and hence caused an ischemic hepatocellular necrosis.

Topics: Anemia; Animals; Communicable Diseases; Endothelium; Fish Diseases; Glycogen; Hematocrit; Injections, Intraperitoneal; Liver; Liver Diseases; Microscopy, Electron; Salmon; Tissue Fixation

Erythropoietic responses of fed and starved species of teleosts, viz., Clarias batrachus and Heteropneustes fossilis, to human urinary erythropoietin and thyroxine have been examined. The effects of these hormones on energy reserves have also been evaluated. Twenty-four C. batrachus were divided into two groups: half were fed regularly; the remaining fish were starved 20 days. On the 21st day each group was further divided into three subgroups of four each and received either saline, thyroxine (8 micrograms), or erythropoietin (6 IU) over 4 consecutive days. The experimental protocol was identical for H. fossilis; however, for H. fossilis two identical studies were conducted approximately 1 year apart. A decline in the rate of erythropoiesis and a stimulatory response to human urinary erythropoietin followed starvation in both species of teleosts. In addition, erythropoietin had a pronounced effect on hepatic glycogenesis of fed H. fossilis and stimulated erythropoiesis in the fed teleosts of both species. Prolonged starvation drastically depleted hepatic glycogen in C. batrachus. In contrast, it had no effect on hepatic glycogen in H. fossilis and on muscle glycogen and protein in both species. In general, while both species could respond to erythropoietin and withstand prolonged starvation, H. fossilis alone exhibited remarkable tolerance to fasting.

Topics: Animals; Energy Metabolism; Erythrocyte Count; Erythropoietin; Fish Diseases; Fishes; Food; Glycogen; Hematocrit; Hemoglobins; Liver Glycogen; Muscle Proteins; Muscles; Starvation; Thyroxine

Nine fish species subjected to various concentrations (5, 10, 15 and 20 ppm) of mercuric nitrate for 4.5 h. The relationship between the concentrations of mercuric nitrate and the fall in renal glycogen was inverse. There was an elevation in liver and muscle glycogen at 5 ppm mercury. Brain glycogen increased to less than 10 ppm and then decreased. Glucose and lactate levels increased with increasing concentration of mercury, and muscle, liver, kidney and brain glycogen decreased. The effects were more marked in major carp than in the other species.

Topics: Animals; Blood Glucose; Fish Diseases; Fishes; Glycogen; Lactates; Mercury; Mercury Poisoning

An inverse relationship was recorded between the concentration of ammonium chloride (5, 10, 15, and 20 ppm) and the fall in pH and dissolved oxygen of water; with ammoniacal nitrogen and carbon dioxide the relationship was reversed. The effect of various concentrations of ammonium chloride (5, 10, 15, and 20 ppm) on tissue glycogen, serum glucose and lactate level was studied in 9 freshwater teleosts from a tropical environment. The fall in tissue (liver, muscle, and brain) glycogen was inversely proportional to ammonia concentration. An elevation in renal glycogen was recorded up to 10 ppm with a decrease thereafter. The greatest fall in tissue glycogen was recorded in the liver (C. mrigala), muscle, brain (C. catla), and kidney (C. mrigala). There was a direct relationship between ammonia concentration and accumulation of glucose and lactate in serum. The decrease in tissue glycogen was greater in major carp species than in murrels or catfish.

Topics: Ammonia; Animals; Blood Glucose; Fish Diseases; Fishes; Fresh Water; Glycogen; Lactates; Water Pollutants; Water Pollutants, Chemical

Hydrocortisone treatment caused a hyperglycaemic state in Clarias batrachus within an hour. The blood glucose values remained significantly increased for 6 days. An initial increase in liver glycogen was followed by a decrease below the normal value. The muscle and brain glycogen levels remained unaffected. A mild degranulation of B cells was seen in the early hours and a conspicuous vacuolation and necrosis of both A and B cells appeared 72-96 h after treatment. Administration of thyroxine resulted in hyperglycaemia within 15 h but a distinct hypoglycaemic condition was seen 4 days after the treatment. Considerable drain in the liver glycogen deposits was noticed between 24 and 72 h while the muscle glycogen showed an increase. The brain glycogen did not change noticeably. Islets of the fishes autopsied between 72 and 96 h contained severely damaged B cells. The A cells remained unaffected. It is suggested that, in addition to several other hormones, hydrocortisone and thyroxine play an important role in carbohydrate metabolism and blood sugar homoeostasis in C. batrachus.

Topics: Animals; B-Lymphocytes; Blood Glucose; Brain; Fish Diseases; Fishes; Glycogen; Hydrocortisone; Hyperglycemia; Islets of Langerhans; Liver Glycogen; Muscles; Thyroxine

Histological changes in the wall of the copulatory sac of normal adult female thorny skates, Raja radiata, were compared with those naturally infected with Trichodina oviducti. The parasites were associated with extensive defoliation of the copulatory epithelium and in some instances had penetrated the submucosa resulting in petechiae. An excessive exudated that appeared at the vent was made up of mucus, sloughed cells and parasites. It is speculated that shedding of the copulatory epithelium may be due to a hyaluronidase-like enzyme. Furthermore, the restriction of T. oviducti to adult skates may be dependent on the presence of certain mucopolysaccharides that are very low or absent in immature skates.

Topics: Animals; Ciliophora; Epithelial Cells; Epithelium; Female; Fish Diseases; Fishes; Glycogen; Glycosaminoglycans; Histocytochemistry; Protozoan Infections; Protozoan Infections, Animal

Topics: Animals; Bird Diseases; Birds; Fish Diseases; Fishes; Glycogen; Starvation; Trematoda; Trematode Infections