Kidney Of Catfish Research Articles

Single-cell transcriptome landscape of the kidney reveals potential innate immune regulation mechanisms in hybrid yellow catfish after Aeromonas hydrophila infection

Aeromonas hydrophila, the pathogen that is the causative agent of motile Aeromonas septicemia (MAS) disease, commonly attacks freshwater fishes, including yellow catfish (Pelteobagrus fulvidraco). Although the kidney is one of the most important organs involved in immunity in fish, its role in disease progression has not been fully elucidated. Understanding the cellular composition and innate immune regulation mechanisms of the kidney of yellow catfish is important for the treatment of MAS. In this study, single-cell RNA sequencing (scRNA-seq) was performed on the kidney of hybrid yellow catfish (Pelteobagrus fulvidraco ♀ × Pelteobagrus vachelli ♂) after A. hydrophila infection. Nine types of kidney cells were identified using marker genes, and a transcription module of marker genes in the main immune cells of hybrid yellow catfish kidney tissue was constructed using in-situ hybridization. In addition, the single-cell transcriptome data showed that the differentially expressed genes of macrophages were primarily enriched in the Toll-like receptor and Nod-like receptor signaling pathways. The expression levels of genes involved in these pathways were upregulated in macrophages following A. hydrophila infection. Transmission electron microscopy and TUNEL analysis revealed the cellular characteristics of macrophages before and after A. hydrophila infection. These data provide empirical support for in-depth research on the role of the kidney in the innate immune response of hybrid yellow catfish.

Interleukin-26 in channel catfish (Ictalurus punctatus): Molecular characterization and immune functional activity

IL-26 is a crucial inflammatory cytokine that participates in defending host cells against infections. We initially cloned and identified the cDNA sequences of interleukin (IL)-26 in channel catfish (Ictalurus punctatus). The open reading frame (ORF) of IpIL-26 was 537 bp in length, encoding 178 amino acids (aa). Constitutive expression of IpIL-26 was observed in tested tissues, with the highest level found in the gill and spleen. To explore the function of IpIL-26 in channel catfish, different stimuli were used to act on both channel catfish and channel catfish kidney cells (CCK). The expression of IpIL-26 could be up-regulated by bacteria and viruses in multiple tissues. In vitro, recombinant IpIL-26 (rIpIL-26) could induce the expression levels of inflammatory cytokines such as TNF-α, IL-1β, IL-6, IL-20, and IL-22 playing vital roles in defending the host against infections. Our results demonstrated that IpIL-26 might be an essential cytokine, significantly affecting the immune defense of channel catfish against pathogen infections.

The Effect of Adding Bacillus NP5 to Feed on Growth, Survival Rate, and Protection Against Aeromonas hydrophila of Catfish (Clarias sp.)

Probiotics are useful organisms in preventing the spread of disease in aquaculture. Therefore this study aims to evaluate the effect of administering Bacillus NP5 on the growth, survival rate, and histology of catfish with Aeromonas hydrophila infection. To achieve this, catfish (7.75 ± 0.02 g) were reared for 45 days with a density of 20 per tank. Furthermore, the study consisted of 4 treatments and 3 replications, namely K+: 0% Bacillus NP5+0.1 mL A. hydrophila injection, K-: 0% Bacillus NP5 + without A. hydrophila injection, A: 0.3% Bacillus NP5, and B: 0.8% Bacillus NP5. The results showed that the addition of probiotics significantly increased the growth and survival rate of catfish (P <0.05) compared to K+. The higher value of specific growth rate was found in treatments A and B (0.22 ± 0.03 and 0.23 ± 0.03% day-1, respectively) and the lowest in K+ (0.14 ± 0.03% day-1). Also, the tissue damage in K+ was higher than in the probiotic treatment. Besides, hyperplasia, congestion, and secondary lamella fusion in the gill tissue were found in the K+, while other treatments were found only in hyperplasia. Melanomacrophages occurred in catfish kidney tissue for all treatments, however, hydropic degeneration was found in the control treatment. The addition of Bacillus NP5 in feed resulted in higher growth, survival, and tissue damage compared to K+. Also, the addition of 0.8% Bacillus NP5 resulted in less catfish tissue damage.

Toxicity bioassay and sub-lethal effects of diazinon on blood profile and histology of liver, gills and kidney of catfish, Clarias gariepinus.

The catfish, Clarias gariepinus, was exposed to different acute concentrations (5-10 mg/l) of diazinon and the Lc50 value was recorded as high as 7.3 mg/l for 96 hours. The fishes exposed to three sub-lethal levels of diazinon (0.73, 1.095 and 1.46 mg/l) for 30 days showed that the pesticide induces changes in different blood parameters. Number of red blood cells (RBC), haemoglobin level and haematocrit values were elevated whereas white blood cells (WBC) count was reduced. Various blood indices like mean corpuscular volume (MCV), mean corpuscular haemoglobine (MCH) and mean corpuscular haemoglobine concentration (MCHC) vary insignificantly in the fish treated with diazinon. Glucose level and activity level of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) was increased in Clarias gariepinus exposed to diazinon. Protein level in plasma of fish treated with pesticide was changed but the change was insignificant. Histological changes in the liver, gills and kidney of fishes exposed to diazinon were apparent when compared to control. Hepatocytes necrosis and bleeding were more distinct in the fishes exposed to pesticide. Glomerulus hypertrophy and bleeding in kidneys; and fusion and degeneration of secondary lamellae and epithelial hyperplasia in gills were also observed in the exposed fish.

Virulent bacteriophage of Edwardsiella ictaluri isolated from kidney and liver of striped catfish Pangasianodon hypophthalmus in Vietnam.

Striped catfish Pangasianodon hypophthalmus farmed in the Mekong Delta, Vietnam, represents an important contribution to Vietnamese aquaculture exports. However, these fish are affected by frequent disease outbreaks across the entire region. One of the most common infections involves white spots in the internal organs, caused by the bacterium Edwardsiella ictaluri. In this study, a virulent phage specific to E. ictaluri, designated MK7, was isolated from striped catfish kidney and liver samples and characterized. Morphological analysis indicates probable placement in the family Myoviridae with a 65 nm icosahedral head and a 147 %%CONV_ERR%% 19 nm tail. A double-stranded DNA genome of approximately 34 kb was predicted by restriction fragment analysis following digestion with SmaI. The adsorption affinity (ka) of the MK7 phage was estimated as 1.6 %%CONV_ERR%% 10-8 ml CFU-1 min-1, and according to a 1-step growth curve, its latent period and burst size were ~45 min and ~55 phage particles per infected host cell, respectively. Of the 17 bacterial strains tested, MK7 only infected E. ictaluri, although other species of Edwardsiella were not tested. E. ictaluri was also challenged in vitro, in both broth and water from a striped catfish pond and was inactivated by MK7 for 15 h in broth and 51 h in pond water. Thus, initial characterization of phage MK7 indicates its potential utility as a biotherapeutic agent against E. ictaluri infection in striped catfish. This is the first report of a lytic phage specific to an important striped catfish pathogen.

DETEKSI BAKTERI GENUS VIBRIO SEBAGAI CAUSATIVE AGENT PADA IKAN LELE SANGKURIANG (CLARIAS GARIEPINUS VAR. SANGKURIANG) DI KOTA TASIKMALAYA

Sangkuriang catfish (Clarias gariepinus var Sangkuriang) is the main commodity that widely cultivated in Tasikmalaya City. However, farmers have difficulty because of the disease which causes death in fish. High mortality is suspected as a vibriosis disease by genus Vibrio because redness wounds on dead fish. The purpose of this study is to know the genus Vibrio which causes of disease in Sangkuriang catfish. 10 samples of fish were taken from Sangkuriang catfish pond culture in Kelurahan Kersanagara Tasikmalaya City which were potentially suspected of vibriosis disease. Isolation of bacteria were done on TCBS medium. Bacterial isolates were collected from fish lesion on the body surface, liver, and kidneys of catfish. Isolation were able to gained 21 isolates and then 5 isolates (VK1, VK5, VK7, VK17, and VK21) were selected based on colony morphology and Postulates Koch’s were tested. The results showed that the clinical symptoms of catfish infected by vibriosis were redness lesions/ulcers on the body surface, hemorrhagic, fluid inside stomach, and fin eroded with redness wound. Bacterial identification through biochemical test revealed the causative agent of catfish disease at brackish pond area were bacteria of the genus Vibrio (VK 1, VK 5, and VK 7), Vibrio vulnificus (VK 17 and VK 21).

Acute Cadmium Toxicity Induced Impairments in the Liver and Kidney of Freshwater Catfish, Heteropneustes fossilis (Bloch)

Background/objective: The heavy metal, Cadmium enters aquatic environment through natural / anthropogenic sources and exerts deleterious effects in fish. Hence, the present study is aimed at investigating the acute Cd toxicity induced histological alterations in the liver and kidney of catfish, Heteropneustes fossilis. Methods: The bioassay was performed in a static renewal regime with H. fossilis exposing to varying acute toxicity concentrations viz., 18.45, 36.9, 73.7, 147.4 and 294.8 mg/l for 96 h. The LC50 was determined to be 44.13 mg/l. Since 100 % mortality occurred in the highest concentrations after 96 h, liver and kidney tissues were collected from fish exposed to the first three lower concentrations. Standard histology protocol was followed to study the histological alterations. Findings: The histological alterations like increased kupffer cell and pycnotic nucleus, ruptured hepatic tissue and nucleus, cellular necrosis and focal necrosis were observed in the liver of fish exposed to Cd. Similarly, vacuolation, increased periglomerular and peritubular space, shrunken glomerulus, melanomacrophages and loss of cytoplasm were observed in the kidney of fish treated with Cd. The intensity of the histological alterations in both liver and kidney was found to be concentration and duration dependent. Hepatic tissues were found to be ruptured in the liver of fish exposed to all the three concentrations viz., 18.45, 36.9 and 73.7 mg Cd/l. The appearance of melanomacrophage aggregates is a generalized non-specific marker, indicating environmental stress. In the present study, melanomacrophages were observed in kidney of fish exposed to 36.9 and 73.7 mg Cd/l. Our present observations on histological alterations in the liver and kidney of H. fossilis were in conformity to the histological observations made in the liver and kidney of various fish species exposed to different toxicants. Applications: The histological alterations in liver and kidney H. fossilis induced by Cd suggest that Cd can be a potential toxicant and hence these alterations can be used as biomarkers to monitor aquatic pollution. Keywords: Acute Toxicity, Cadmium, Histology, Heteropneustes fossilis, Kidney, Liver

Stenotrophomonas maltophilia as an opportunistic pathogen in cultured African catfish Clarias gariepinus (Burchell, 1822)

Indian catfish production is increasing over the years so as the frequency of diseases. In this report, the isolation of Stenotrophomonas maltophilia from the kidney of Clarias gariepinus juvenile with distended abdomen along with its phenotypic, molecular and phylogenetic characteristics was described. The diseased catfish juveniles in an earthen pond (1500m3) with high stocking density (≈60nos/m3) had body discoloration, fin/tail rot, focal cutaneous hemorrhage, distended abdomen, inflammation of internal organs and visceral hemorrhage. The abdominal cavity was filled with transparent jelly-like mass. The bacterial strain isolated from the kidney of catfish formed a monophyletic group with other strains of S. maltophilia based on genotypic characters and phylogenetic analyses. The strain S. maltophilia SK1 (NCBI accession number KP898215) was alpha-hemolytic, protease and lipase positive and weakly pathogenic to C. gariepinus juveniles. It caused only 35±5% mortality at a level of 1.40×107 cells/fish via intraperitonial injection. While the intramuscular injection caused only 10% mortality. The dead fish up on challenge had distended abdomen with jelly-like mass. Understanding the pathology and pathogenesis of this emerging pathogen in cultured catfish would help manage the disease. Statement of relevance1Stenotrophomonas maltophilia is considered as an opportunistic pathogen of human and fish.2This species is emerging as a pathogen in cultured catfish Clarias gariepinus (Burchell, 1822).3Understanding the pathology and pathogenesis of this species would help manage the disease.

Using 1-D 1H and 2-D 1H J-resolved NMR metabolomics to understand the effects of anemia in channel catfish (Ictalurus punctatus)

Anemia is a widespread hematological disorder in vertebrates. In channel catfish (Ictalurus punctatus), anemia is a persistent problem in culture environments, however, its causes and physiological impacts are not well understood. To better understand the symptoms and characterize associated biomarkers of anemia, 1-D 1H and 2-D 1H J-resolved NMR were used to analyze metabolite changes in healthy and anemic channel catfish kidney and liver tissue. Additionally, standard physiological analytical techniques were used to analyze blood plasma. NMR analyses revealed energy sources such as glucose were depleted and many metabolites associated with anaerobic metabolism or alternative energy pathways such as lactate, creatine, alanine, acetate and myo-inositol had changed. Energy demanding processes were reduced, such as muscle function, as indicated by reductions in taurine and inosine, and protein synthesis. Stress and oxidative stress related metabolites changed, with increases in valine, leucine and isoleucine and decreases in glutathione. Inhibitory neurotransmitters such as 4-aminobutyric acid (GABA) increased, and excitatory neurotransmitters such as glutamine and glutamate generally decreased, although there were tissue-specific differences. Immune function also decreased in anemic fish. Blood analyses revealed decreased respiratory gas transport capabilities through reductions in erythrocytes and hemoglobin-markers. Taken together, these tissues and analytical techniques produced complementary results, and metabolite expression in anemic channel catfish was similar to that observed in other vertebrates exposed to anoxia, severe hypoxia or experiencing oxidative stress from deficiencies in iron homeostasis.

Depletion of melamine and cyanuric acid in kidney of catfish Ictalurus punctatus and trout Oncorhynchus mykiss.

A risk assessment conducted in 2007 identified significant knowledge gaps about tissue residues of melamine and related triazine analogs such as cyanuric acid in animals that had eaten contaminated food. The USFDA subsequently designed studies to determine residue levels in muscle, serum, and kidneys of catfish and trout given a single gavage dose of 20mg/kg body weight (BW) of melamine, cyanuric acid, or 20mg/kg BW of both compounds simultaneously. Renal triazines were determined by LC-MS/MS at postdose days 1, 3, 7, 14, 28 (and day 42 for trout). When dosed individually, melamine and cyanuric acid kidney residues depleted much faster than those in fish given both compounds together. Combined dose residue depletion was punctuated by extreme outliers due to the formation of persistent renal melamine cyanurate crystals.

Acute toxicity and histological changes in gills, liver and kidney of catfish, Heterobranchus bidorsalis exposed to cypermethrin concentration

Fingerlings of Heterobranchus bidorsalis (mean weight 11.88 g) were exposed to various sub-lethal concentrations of cypermethrin (0.032, 0.034, 0.036, 0.038 and 0.040 ml/L), a toxicant, and the histological effects were recorded. The 96 h bioassays were also conducted to determine the lethal concentration (LC50) of cypermethrin on the test fish. The 96 h LC50 of H. bidorsalis exposed to Cypermethrin was 0.036 ml/L. The physical reactions observed in the fish were: discolorations of the skin, erratic swimming, loss of reflex, hyperactivities, surfacing, and these effects increased with increasing concentration of the toxicants and duration of exposure. The pH and dissolved oxygen of the test media showed slight decrease from lowest concentration (0.032 ml/L) to the highest concentration (0.040 ml/L) while the temperature increased slightly with increasing concentration (0.032, 0.034, 0.036, 0.038 and 0.040 ml/L). The histological examination of the gills, kidney, livers of the fish after 96 h showed pathological changes and alterations such as gills infiltration, inflammation of the livers, vacuolation and necrosis. There was excessive necrosis degeneration in higher concentrations (0.038 and 0.040 ml/L) and there was increase in mortality as the concentrations increased. Key words: Histology, cypermethrin, xenobiotic, Heterobranchus bidorsalis, acute toxicity, LC50.

Oxidative enzymes in tissues of the catfish (Clarias gariepinus) exposed to varying levels of cadmium

The activities of some oxidative enzymes (aldehyde oxidase, AO, EC 1.2.3.1; xanthine oxidase, XO, EC 1.17.3.2; sulphite oxidase, SO, EC 1.8.3.1; and monoamine oxidase, MO, EC 1.4.3.4) were investigated in the liver, gill, kidney, brain and muscle of a variety of African catfish (Clarias gariepinus) after 7 and 21 days of exposure to 0.1, 0.2 and 0.4 ppm cadmium (Cd) in ambient water. MO, SO and AO activities were significantly (p < 0.05) decreased in a dose-dependent manner in the liver, kidney and gill in the 7-day Cd-exposed fish when compared to control. Conversely, brain MO, AO and SO activities were significantly (p < 0.05) elevated in a dose-dependent manner in the same fishes relative to control. As in the 7-day Cd-exposed fish, the activities of MO, AO and SO were significantly (p < 0.05) decreased in a dose-dependent manner in the gill, kidney and liver of catfish exposed for 21 days. Same is true for XO in these organs after both duration of exposure, except in the liver where no significant change was observed relative to control. The inhibition of these oxidative enzymes in the liver, gill and kidney of catfish may interfere with their biotransformation function, and ultimately the survival of the fish may be compromised.

Bioaccumulation of cadmium and its biochemical effect on selected tissues of the catfish (Clarias gariepinus)

The present study examines the pattern of accumulation of cadmium (Cd) and its biochemical effects on selected tissues of a variety of African catfish (Clarias gariepinus), after exposure to various doses of Cd. The results obtained indicate that at the end of 21 days of exposure, the total tissue organ cadmium concentration followed the pattern kidney > gill > liver > muscle for each of the exposure concentrations. The levels of Cd in these organs were higher than those in ambient water. Moreover, while the rate of uptake of Cd increased with time in the kidney, liver and muscle, it decreased in the gill. Superoxide dismutase (SOD) was significantly elevated only in the kidney of catfish treated with 0.2 and 0.4 ppm of Cd for 7 days compared with the control. Conversely, gill SOD was significantly decreased in the same concentrations of Cd-treated catfish relative to the control. Statistically similar levels of SOD were observed in the liver, brain and muscle with all the treatments after the same duration of treatment. In the fish exposed for 21 days, SOD activity was significantly decreased in the kidney with a corresponding increase in lipid peroxidation (LPO), but it manifested only with the 0.2- and 0.4-ppm Cd treatment relative to the control. In the liver, however, Cd exposure significantly increased SOD in the 0.2- and 0.4-ppm treatments of the same duration. In conclusion, the present study indicates that the accumulation of Cd and its effect on SOD and LPO in C. gariepinus is dependent on concentration, tissue and time.

Induction of lauric acid hydroxylase activity in catfish and bluegill by peroxisome proliferating agents

In mammals, sensitivity to peroxisome proliferation by peroxisome proliferating agents (PPAs) appears to be correlated with inducibility of lauric acid hydroxylase activity. Bluegill and catfish have been shown to respond to PPAs by induction of lauric acid hydroxylase immunoreactive proteins (Haasch, 1996). In this investigation, induction of lauric acid hydroxylase activity was confirmed by HPLC and mass spectral analysis of specific hydroxylation products and possible species-specific differences in metabolism were investigated. Male bluegill, channel catfish and rat, were administered the model PPAs, clofibrate (200 mg kg −1, i.p.), ciprofibrate (100 mg kg −1, i.p.), or olive oil as vehicle control (both sexes of catfish), 48 h prior to hepatic, trunk kidney (catfish only) or kidney (rat) microsome preparation. In general, total metabolism of lauric acid was similar in all species, but female catfish metabolize lauric acid to a greater extent than males. Ciprofibrate treatment produced significant induction of ω- and ω-6 hydroxylation in male catfish kidney. In male bluegill liver, ω-, ω-4 and ω-5 hydroxylations were significantly induced by clofibrate treatment. The data indicate that induction of lauric acid hydroxylase cytochrome(s) P450 occurs in PPA-exposed fish which may be a consideration for environmentally-exposed responsive species.

Induction of CYP2M1 and CYP2K1 lauric acid hydroxylase activities by peroxisome proliferating agents in certain fish species: Possible implications

In many higher vertebrates, species and gender-specific sensitivity to peroxisome proliferating agents (PPAs) and their toxic effects has been described. Sensitivity may correlate with the induction of lauric acid hydroxylase (LAH) activity. In rainbow trout ( Oncorhynchus mykiss) LAH has been identified with at least two cytochromes P450, CYP2M1 and CYP2K1. Previously, bluegill ( Lepomis macrochirus) and catfish ( Ictalurus punctatus) had been shown to produce CYP2M1 and CYP2K1 immunoreactive protein induction upon treatment with PPAs. The current research extends that observation by demonstration of the associated lauric acid hydroxylase activities after exposure to PPAs. Male bluegill and catfish were treated using a single i.p. injection with olive oil vehicle or ciprofibrate (a model PPA; 100 mg kg −1) or clofibrate (less potent PPA) 48 h prior to microsome preparation. Olive oil-treated female catfish liver and kidney microsomes metabolize lauric acid to a greater extent than male microsomes (83 vs 40% and 77 vs 5%, respectively). Male bluegill liver and male catfish kidney exhibit significant induction of specific LAH after PPA treatment. These observations, taken together with previous work in mammals, may portend possible adverse consequences to sensitive fish species exposed to environmental chemical contamination by PPAs.

Induction of anti-trout lauric acid hydroxylase immunoreactive proteins by peroxisome proliferators in bluegill and catfish

Various chemicals such as phthalate esters, hypolipidemic drugs, solvents like trichloroethylene, and certain herbicides have been identified as peroxisome proliferating agents (PPAs). In many vertebrates, species- and even gender-specific sensitivities to peroxisome proliferation (PP) and toxicity, have been described and may correlate with inducibility of lauric acid hydroxylase activity. Little is known about PP in fish. The rainbow trout does not appear to be inducible for lauric acid hydroxylases (LMC1 and LMC2; CYP2M1 and CYP2K1, respectively) in response to the hypolipidemic drug, clofibrate. Fish other than trout, such as bluegill and catfish, are more acutely sensitive to phthalate ester toxicity. In this study, bluegill and catfish were examined for inducibility of anti-trout LMC1 and LMC2 immunoreactive proteins, 48 h after intra-pentoneal (i.p.) administration of olive oil vehicle, 200 mg/kg clofibrate, or 100 mg/kg ciprofibrate. In control animals, immunoreactive proteins were recognized in a sex-specific manner in both bluegill and catfish liver, and in catfish kidney. In treated animals, male immunoreactive proteins were induced to a greater extent than female, and ciprofibrate was the more potent inducer. The response of bluegill and catfish, therefore, is similar to the response of PPA-sensitive species.

Non-specific cytotoxic activity of teleost leukocytes

The existence of lymphoid cells with “natural” killer activity in mammals and birds has been known for some time. Several previous reports have demonstrated similar activity in carp and catfish kidney leukocytes. However, the activity previously reported was directed towards established mammalian cell lines. In this report we confirm the existence of spontaneous killer activity in other species of teleosts, including salmonids. This spontaneous cytotoxic activity is directed towards several established teleost, as well as mammalian, cell lines. Cytotoxic activity appears to be optimal at 20°C in an 8 hour 51Cr release assay. The RTG-2, AS, GS and EPC cell lines of teleost origin are susceptible to lysis by kidney, spleen, and blood leukocytes of Salmo salar , Salmo gairdneri , and Notemigonus crysoleucas . Furthermore, the susceptibility of the RTG-2 and AS teleost cell lines to killing by kidney leukocytes of both S . salar and S . gairdneri was significantly enhanced by preinfection of the target cells with infectious pancreatic necrosis virus.

Body Fluid Pools, Kidney Function, and Acid-Base Regulation in the Freshwater Catfish Ictalurus Punctatus*

ABSTRACT Resting catfish excreted a urine with electrolyte concentrations about that of blood, with very low concentrations of ammonia and lactic acid, only slightly acid pH, and a small resultant net base excretion. At 26 °C, the intracellular pH was normally 0·51 units lower than the extracellular pH. Both were depressed following the onset of hypercapnia, but there was compensation for both by 24 h, so that pHi was near control values. Consequently the whole body CO2 pool increased from 195 to 4·77 m-equiv kg−1 during hypercapnia, with about 1·50 m-equiv by active means, and the other 1·32 by passive (non-bicarbonate) buffering. The renal response to hypercapnic acidosis was to switch from a small net base excretion to a net acid excretion, which persisted for up to 10 h, and accounted for about 14% of the total active bicarbonate compensation. There was no statistically significant renal response to an infused HC1 load, but the whole body base excretion rate declined so as to indicate that about 25 % of the infused load was excreted in the first 2 h, presumably by the gills. The catfish kidney appears to participate in acid-base regulation in a sig- nificant, but quantitatively minor way, implying that the gills are the principal site of ion transfer in regulating the whole body SID.