Effects of cypermethrin and carbofuran on certain hematological parameters and prediction of their recovery in a freshwater teleost, Labeo rohita (Hamilton)

Assessing haematological parameters and probable toxicity analysis in two coastal fish species at harbouring areas of Digha coastal belt, West Bengal, India

Coastal ecosystems are vital for maintaining the biodiversity and human livelihoods, but they are increasingly subjected to anthropogenic pressures, including pollution from various sources. Present work intends to assess the possible threats in coastal ecosystem as well as coastal fish species, in particular, through haematological parameters caused due to exposure of environmental contaminants like polycyclic aromatic hydrocarbons (PAHs), potentially toxic metals (PTMs), etc. This study analysed the haematological parameters and probable toxicity levels in two important coastal fish species, viz., Mystus sp. and Mugil sp. widely available in Digha coastal belt. Different haematological parameters, such as WBCs (White Blood Cells), Lym (Lymphocytes), Gran (Granulocytes), Mid (Monocytes), RBCs (Red Blood Cells), HCT (Haematocrit) value, MCV (Mean Corpuscular Volume), MCH (Mean Corpuscular Haemoglobin), MCHC (Mean Corpuscular Haemoglobin Concentration), RDW- CV (Red Cells Distribution Width-Co-efficient of Variation), RDW- SD (Red Cells Distribution Width-Standard Deviation), PLT (Total Platelet Count), MPV (Mean Platelet Volume), PDW- SD (Platelet Distribution Width-Standard Deviation), PDW- CV (Platelet Distribution Width-Co-efficient of Variation), PCT (Plateletcrit), PLCR (Platelet Large Cell Ratio), PLCC (Platelet Large Cell Count) and many others were measured directly through Erba H360 Haematology Analyser, simultaneously air dried blood smear was stained by Haematoxylin-Eosin(H-E) and Giemsa stain for assessing morphometric alterations of RBCs, WBCs, platelets as well as to determine the differential counts of WBCs by observing through Leica DM2000 microscope. Evidence of several abnormalities in the erythrocyte's nucleus (ENAs) and the abundance of abnormal celled erythrocytes (ECAs), carcinoma (lymphoproliferative disorder, polycythaemia vera, Hodgkin lymphoma and non-Hodgkin lymphoma), elevation of WBCs content, Lym %(Lymphocyte percentage), Eo(Eosinophils), monocytes, HCT and gross depletion of Ne(Neutrophils), basophils, and PLCR levels indicated a sign of major impact of contamination to two intoxicated fishes which may also affect the human being through food chain and may result into leukaemia in mammalian species, finally. However, comprehensive evaluation of the long-term impacts of the contaminants like PAHs and/or PTMs, etc., on fish populations, human health risk and coastal ecosystem is required to be addressed.

Cypermethrin: An Emerging Pollutant and Its Adverse Effect on Fish Health and some Preventive Approach-A Review

Pesticides are substance that are used to manage pests, such as aquatic weeds, plant diseases and insects. It has been shown that these substances are highly hazardous to fish as well as other organisms that are part of the food chain. The presence of cypermethrin in food and groundwater has raised environmental concerns, there is a need to develop economical, rapid, and reliable techniques that can be used for field applications Many studies have shown that Cypermethrin (CYP) can cause toxic effect in various animals including fishes. But the molecular mechanism behind the toxicity mediated Cypermethrin (CYP) at genome levels and proteome levels is still need to be studied. However, there is a gap in emerging and undeveloped nations to begin to use these methods and several other recently developed approaches to inhibit the negative consequences and enhance health which may be profitable. The toxicological information currently available might be used to gain a clear understanding of the possibilities of these synthetic pyrethroid insecticides causing various health hazards to environmental and provides insight for future research evaluating the toxic effects of pyrethroid insecticides. This present review article is concerned with the toxicological effects of pesticides and a brief overview of sources, classification of pesticides with an emphasis on the effects of Cypermethrin (CYP) on fish as well mode of toxicity and the mechanism of action (CYP) and toxicity signs in several fish species have been illustrated. The primary controls and appropriate preventive measures that must be adopted are also discussed.

Poison in the water: Arsenic's silent assault on fish health

Arsenic occurs across the world in freshwater and marine environments, menacing the survival of aquatic organisms. Organic and inorganic forms of this substance can be found, in which the inorganic form is more hazardous than the organic form. Most aquatic bodies contain inorganic arsenic species, but organic species are believed to be the dominant form of arsenic in the majority of fish. Natural and anthropogenic both are the sources of water contamination with arsenic. Its bioaccumulation and transfer from one trophic level to another in the aquatic food chain make arsenic a vital environmental issue. Continuous exposure to low concentrations of arsenic in aquatic organisms including fish leads to its bioaccumulation, which may affect organisms of higher trophic levels including large fishes or humans. Humans can be exposed to arsenic through the consumption of fish contaminated with arsenic. Hence, the present review facilitates our understanding about sources of arsenic, its bioaccumulation, food chain transfer, and its effect on the fish health. Also, "Poison in the Water: Arsenic's Silent Assault on Fish Health" serves as a wake-up call to recognize the pressing need to address arsenic contamination in water bodies. By understanding its devastating impact on fish health, we can strive to implement sustainable practices and policies that safeguard our precious aquatic environments and ensure the well-being of both wildlife and human communities that depend on them.

Effect of glyphosate-based herbicide roundup on hemato-biochemistry of Labeo rohita (Hamilton, 1822) and susceptibility to Aeromonas hydrophila infection

In the present study, comprehensive research was executed to investigate the salient toxic effects of glyphosate herbicide in static water system by evaluating the haemato-biochemical profiles of Labio rohita. A challenge study against Aeromonas hydrophila was conducted to determine disease susceptibility of the fish, treated to varying concentrations of commercial-grade glyphosate herbicide. A static range finding bioassay and definitive test revealed that the 96-h LC50 value of glyphosate was 10.16 mg L-1. The experimental fish were subjected to three sub-lethal concentrations of 2.06, 1.03, and 0.63 mg l-1 for 28 days and changes were documented bi-fortnightly to study haemato-biochemical alterationsin the fish. Significantly (p < 0.05) low values in red blood corpuscles (RBC), hemoglobin (Hb), and hematocrit value (Hct) were documented. In contrast, a significant (p < 0.05) escalation in white blood corpuscles (WBC) was documented in comparison to the control. Biochemical and stress markers such as blood glucose, total protein, and alkaline phosphatase (ALP) were significantly (p < 0.05) low, whereas serum glutamate pyruvate transaminase (SGPT) and serum glutamate oxaloacetate transaminase (SGOT) escalated significantly (p < 0.05). Chronic exposure to glyphosate, on the other hand, had the least effect on the Na+ and K+ ions. Further, a challenge assay against A. hydrophila at three sub-lethal glyphosate concentrations demonstrated a synergistic impact that reduced the fish survivability. The findings conclude that persistent low glyphosate concentrations in aquatic ecosystems show significant pathophysiological changes in L. rohita, with increased vulnerability to infections. Altogether, our findings indicate the need to further study the possible assessment for a sustainable bio-remediation technique, mitigation of the detrimental effects of glyphosate exposure in fish, and recommendation of an acceptable residue concentration of the glyphosate in aquatic ecosystem.

Toxicological effects of meloxicam on physiological and antioxidant status of common carp (Cyprinus carpio)

BACKGROUND

Fish in aquatic environments are end consumers of the food chain and are widely used for the evolution effects of environmental pollution and their interactions in aquatic ecosystem.

OBJECTIVE

In the present study, common carp (Cyprinus carpio) fingerlings were selected to assess the potential risk and aquatic toxicity of meloxicam as a non-steroidal anti-inflammatory and a commonly used pharmaceutical drug.

METHODS

In order to evaluate meloxicam toxicological effect on haematological, antioxidant status, enzymological and histological parameters, based on its LC50 24 h acute toxicity (10.05 mg L-1 ), fish fingerlings were exposed to four doses of meloxicam including; 0 (control), 0.1 (low), 1 (medium) and 2 mg L-1 (high) under static bioassay method for 28 days.

RESULTS

The results showed that sublethal doses of meloxicam significantly decreased alanine aminotransferase, alkaline phosphatase, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) levels in comparison with the control group after 28 days (p < 0.05). However, red blood cell, haematocrit, haemoglobin and malondialdehyde values in fish exposed to meloxicam significantly increased alongside its concentration (p < 0.05) more than the control group after 28 days. SOD, CAT and GPX mRNA expression levels in gill, liver, kidney and brain organ of fish under meloxicam treatment were significantly down-regulated compared to the control group (p < 0.05). Histopathological assessment showed the increased vacuolation in hepatocytes in liver of fish exposure to medium and high doses of meloxicam.

CONCLUSION

In conclusion, meloxicam induces oxidative stress in common carp which results a disruption of physiological and health status of this species based on our current findings.

Variations in the Behaviour, Survival, Haematology, and Biochemistry of Ctenopharyngodon idella (Grass Carp) After Exposure to Commercial Grade Atrazine

The current study assessed the harmful effects of Atrazine (ATZ) herbicide on haematology and biochemistry of the freshwater fish Ctenopharyngodon idella, a commercially significant fish in Pakistan. C. idella (13 ± 8.4 cm; 132 ± 5.6 g) was exposed to graded levels of ATZ, and its 96-hour LC₅₀ value at 25°C was calculated to be 150.5 µl/L. After exposure to ATZ, fish displayed rapid movements, a loss of balance in position and equilibrium, anxious swimming patterns, colour changes, and increased mucous production. The MCHC, MCH, RBCs, and Hb in C. idella decreased significantly (P < 0.05), whereas the MCV, Ht, and WBCs were significantly increased (P < 0.05). At different time intervals (24, 48, 72, and 96 h) following ATZ administration (50, 100, 150, and 200 µl/L), biochemical analysis significantly decreased (P < 0.05) triglyceride, total protein, cholesterol, and albumin levels, whereas glucose levels significantly increased (P < 0.05). We concluded that ATZ is toxic to C. idella, altering their haematology and blood biochemistry even after only a brief exposure.

Toxicological effect of endocrine disrupting insecticide (deltamethrin) on enzymatical, haematological and histopathological changes in the freshwater iridescent shark, Pangasius hypothalamus

This study investigated the deltamethrin (DMN) induced harmful effects on Pangasius hypophthalmus using enzymatic activity, haematological, and histopathological changes. LC₅₀ value was 0.021mg/L at 96h, and sublethal toxicity was tested for 45 days at two `concentrations (i.e., 1/5^th and 1/10^th of LC₅₀). Haematological parameters and enzymatic activities significantly changed between DMN-exposed and control groups (p<0.05). Histopathologically, both DMN doses induced liver hyperemia, hepatic cell rupture, necrosis, hypertrepheoid bile duct, shifting nuclei, vascular haemorrhage, and hepatocyte degeneration, while in gill, secondary lamellae destruction, a fusion of adjacent gill lamellae, hypertrophy, hyperplasia, adhesion, and fusion were noticed. Kidney developed melanomacrophages, increased periglomerular and peritubular space, vacuolation, decreased glomerulus, hyaline droplets in tubular cells, loss of tubular epithelium, distal convoluted segment hypertrophy, and granular layer in brain pyramid and Purkinje cell nucleus. But, limiting pesticide impacts on freshwater fish and their habitat requires a holistic, cradle-to-grave approach and toxicological studies.

Toxic effects of the synthetic pyrethroid permethrin on the hematological parameters and antioxidant enzyme systems of the freshwater fish Cyprinus carpio L

This study investigated changes in hematological and antioxidant parameters of carp exposed to two different doses of synthetic pyrethroid permethrin (control, vehicle, 10 ppm, and 20 ppm) for two different periods (4 days and 21 days). Hematological analyses were then performed on a veterinary Ms4 (Melet Schloesing, France) blood counter using commercially available kits (Cat. No. WD1153). Buege and Aust for MDA, Luck for CAT, McCord and Frivovich for SOD, Lawrence and Burk methods for GSH-Px were used to determine antioxidant parameters. Decreases in RBC count, Hb amount, Hct value, granulocyte ratios, and increases in total WBC and lymphocyte ratios were statistically significant in both dose groups treated with permethrin compared to the control group (p < 0.05). However, there was no statistically significant difference in monocyte ratios (p > 0.05). Overall, permethrin exposure caused an increase in MDA levels in the liver and gill tissues of carp in both dose and duration groups compared to the control group. Also, no statistically significant difference between the two dose groups in the liver tissue was observed in terms of duration (p > 0.05). Nonetheless, the increase in MDA levels in PERM10 and PERM20 dose groups in the gill tissues over 21 days was statistically significant (p < 0.05). Furthermore, permethrin exposure increased CAT, SOD, and GSH-Px enzyme activities in the gill tissue, while impacting in the opposite direction the liver tissue. Finally, regarding MDA, CAT, SOD, and GSH-Px levels, the control, and control acetone dose groups of all experimental groups were observed to be similar (p > 0.05). As a result, permethrin produced a toxic effect on Cyprinus carpio, triggering changes in blood parameters and inducing the antioxidant enzyme system.

A detailed look at the impacts of biofloc on immunological and hematological parameters and improving resistance to diseases

The innate immunity of invertebrates serves as a critical trait that provides a valuable foundation for studying the common biological responses to environmental changes. With the exponential growth of the human population, the demand for protein has soared, leading to the intensification of aquaculture. Regrettably, this intensification has resulted in the overuse of antibiotics and chemotherapeutics, which have led to the emergence of resistant microbes or superbugs. In this regard, biofloc technology (BFT) emerges as a promising strategy for disease management in aquaculture. By harnessing the power of antibiotics, probiotics, and prebiotics, BFT offers a sustainable and eco-friendly approach that can help mitigate the negative impacts of harmful chemicals. By adopting this innovative technology, we can enhance the immunity and promote the health of aquatic organisms, thereby ensuring the long-term viability of the aquaculture industry. Using a proper carbon to nitrogen ratio, normally adding an external carbon source, BFT recycles waste in culture system with no water exchange. Heterotrophic bacteria grow along with other key microbes in the culture water. Heterotrophs play a major role in assimilating ammonia from feed and fecal waste, crucial pathway to form suspended microbial aggregates (known as 'biofloc'); while chemoautotrophs (e.g. nitrifying bacteria) oxidize ammonia into nitrite, and nitrite into nitrate promoting a healthy farming conditions. By using a highly aerated media and an organic substrates that contain carbon and nitrogen, protein-rich microbes are able to flocculate in culture water. Several types of microorganisms and their cell components have been studied and applied to aquatic animals as probiotics or immunostimulants (lipopolysaccharide, peptidoglycan, and 1-glucans) to enhance their innate immunity and antioxidant status, thereby enhancing their resistance to disease. In recent years, many studies have been conducted on the application of BFT for different farmed aquatic species and it has been observed as a promising method for the development of sustainable aquaculture, especially due to less use of water, increased productivity and biosecurity, but also an enhancement of the health status of several aquaculture species. This review analyses the immune status, antioxidant activity, blood and biochemical parameters, and level of resistance against pathogenic agents of aquatic animals farmed in BFT systems. This manuscript aims to gather and showcase the scientific evidences related to biofloc as a 'health promoter' in a unique document for the industry and academia.

Toxicological effect of endocrine disrupting heavy metal (Pb) on Mekong silurid Pangasius catfish, Pangasius hypophthalmus

The current study aimed to investigate the effects of lead nitrate exposure on the enzymatical, haematological, and histological changes in the gill, liver, and kidney of Pangasius hypophthalmus. The fish were divided into six groups and treated with different Pb concentrations. The LC₅₀ value of Pb was 55.57 mg/L at 96 h for P. hypophthalmus, and sublethal toxicity was assessed for 45 days at 1/5th (11.47 mg/L) and 1/10th (5.57 mg/L) of LC₅₀ concentration. Enzymes such as aspartate aminotransferase (AST), alanine aminotransferase (ALT) levels, alkaline phosphate (ALP), and lactate dehydrogenase (LDH) content increased significantly during sublethal toxicity of Pb. The reduction of HCT and PCV indicates an anemic condition due to the toxicity of Pb. Differential leucocytes, lymphocytes, and monocytes and their % values significantly decreased, indicating Pb exposure. The main histological changes observed in the gills were the destruction of secondary lamellae, the fusion of adjacent gill lamellae, primary lamellae hypertrophy, and severe hyperplasia, while in kidney exposed to Pb showed melanomacrophages, increased periglomerular, peritubular space, vacuolation, shrunken glomerulus, destruction of tubular epithelium, and hypertrophy of distal convoluted segment. The liver showed severe necrosis and rupture of hepatic cells, hyper trepheoid bile duct, shifting of nuclei, and vascular hemorrhage, while in the brain, binucleus, mesoglea cells, vacuole, and ruptured nucleus were observed. In conclusion, P. hypophthalmus, which has been exposed to Pb has developed a number of toxicity markers. Consequently, prolonged exposure to higher Pb concentrations may be harmful to fish health. The findings strongly suggest that the lead had a detrimental impact on the P. hypophthalmus population, as well as on the water quality and non-target aquatic organisms.

Drinking Water Sources along the Banks of Buriganga River of Bangladesh are Polluted and Possess Serious Health Risks: A Comprehensive In Vivo Analysis

Background

The river Buriganga, one of the major dumping zones of industrial wastes in Bangladesh, is responsible for contaminating the drinking water sources along its length. This study aimed to assess the water quality from these sources by monitoring the changes in hematological, biochemical, and histological parameters caused in healthy rats due to their consumption.

Methods

Using ethylenediaminetetraacetic acid (EDTA) as an anticoagulant agent, hematological and biochemical analyses of Sprague-Dawley rat models were executed in this study. Following blood sampling, the rats were sacrificed, and the heart, lungs, kidneys, liver, and spleen were separated to carry out the histological analysis. Later, to perform the statistical analysis, SPSS, V.25.0 was utilized.

Results

A significant rise (p < 0.02) in body weight was recorded due to increased protein synthesis, inflammations; increased lymphocyte, white blood cell (WBC), and neutrophil count but hemoglobin (20.0 ± 1.39 g/dL vs. 15.25 ± 0.36 g/dL; p) and red blood cell (RBC) count ((6.24 ± 0.45) × 106/µL vs. (5.47 ± 0.34) × 106/µL)) decreased due to infections and hematopoietic stem cell poisoning by pathogens in water samples. Elevated (p < 0.01) serum urea, creatinine, alanine, and aspartate aminotransferase levels indicated kidney malfunction and hepatic tissue necrosis. Histological analysis revealed gross lesions, internal hemorrhages in the brain; inflammations, granulomas, migrating macrophages in the spleen; fibrosis (resulting in hypo-perfusion), and collagen formation in cardiac muscles.

Conclusions

The findings in this study provide comprehensive evidence, based on in vivo analysis, that the water bodies around the Buriganga river are likely to be contaminated with toxic chemicals and microbial entities making them unfit for human consumption.

Acute and sublethal effects of acrylamide on the freshwater fish Anabas testudineus (Bloch, 1792)

Acrylamide, a synthetic compound, has a wide range of industrial applications that find multiple ways to reach aquatic ecosystem. The median lethal concentration of acrylamide determined using probit analysis in the fish Anabas testudineus was 132 µg L^-1 concentration together with altered behavioral patterns. Hematological and antioxidant status was evaluated at a sublethal concentration (one-tenth of LC₅₀-96 h), i.e., 13.2 µg L^-1 concentration for 24, 48, 72, and 96 h. A reduction in erythrocytes count, hemoglobin content, and packed cell volume with a significant (P < 0.05) increase in leukocyte counts and differential counts were observed. Erythrocyte indices like mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) increased, whereas the mean corpuscular hemoglobin concentration (MCHC) showed a significant (P < 0.05) decrease when compared with control groups. The activities of superoxide dismutase, catalase, and glutathione reductase in gill tissues showed significant (P < 0.05) reduction, whereas the levels of hydrogen peroxide and lipid peroxidation increased significantly (P < 0.05) indicating oxidative stress. The findings suggest that acrylamide at sublethal concentration caused alteration in hematological parameters and induced oxidative stress in gill tissue of the fish A. testudineus. Hence, restrictions on the use of acrylamide in food and industrial products are recommended since humans are the direct consumer of fish products.

Impact of sublethal phenol in freshwater fish Labeo rohita on biochemical and haematological parameters

Phenol, an aromatic chemical commonly found in domestic and industrial effluents, upon its introduction into aquatic ecosystems adversely affects the indigenous biota, the invertebrates and the vertebrates. With the increased demand for agrochemicals, a large amount of phenol is released directly into the environment as a byproduct. Phenol and its derivatives tend to persist in the environment for longer periods which in turn poses a threat to both humans and the aquatic ecosystem. In our current study, the response of Labeo rohita to sublethal concentrations of phenol was observed and the results did show a regular decrease in biochemical constituents of the targeted organs. Exposure of Labeo rohita to sublethal concentration of phenol (22.32 mg/L) for an epoch of 7, 21 and 28 days shows a decline in lipid, protein, carbohydrate content and phosphatase activity in target organs such as the gills, muscle, intestine, liver and kidney of the fish. The present study also aims to investigate the toxic effects of phenol with special reference to the haematological parameters of Labeo rohita. At the end of the exposure period, the blood of the fish was collected by cutting the caudal peduncle with a surgical scalpel. And it was observed that the red blood corpuscle count (RBC), white blood corpuscle (WBC), haemoglobin count (Hb), packed cell volume (PCV), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) values showed a decline after exposure to phenol for 7 days, while white blood corpuscle (WBC) shows an increased count. At 21 days and 28 days, all the haematological parameters showed a significant decrease.

Blood biomarkers as diagnostic tools: An overview of climate-driven stress responses in fish

Global climate change due to anthropogenic activities affects the dynamics of aquatic communities by altering the adaptive capacities of their inhabitants. Analysis of blood provides valuable insights in the form of a comprehensive representation of the physiological and functional status of fish under various environmental and treatment conditions. This review synthesizes currently available information about blood biomarkers used in climate change induced stress responses in fish. Alterations in informative blood-based indicators are used to monitor the physiological fitness of individual fishes or entire populations. Specific characteristics of fish blood, such as serum and plasma metabolites, cell composition, cellular abnormalities, cellular and antioxidant enzymes necessitate adapted protocols, as well as careful attention to experimental designs and meticulous interpretation of patterns of data. Moreover, the sampling technique, transportation, type of culture system, acclimation procedure, and water quality must all be considered for valid interpretation of hemato-biochemical parameters. Besides, blood collection, handling, and storage time of blood samples can all have significant impacts on the results of a hematological analysis, so it is optimal to perform hemato-biochemical evaluations immediately after blood collection because long-term storage can alter the results of the analyses, at least in part as a result of storage-related degenerative changes that may occur. However, the scarcity of high-throughput sophisticated approaches makes fish blood examination studies promising for climate-driven stress responses in fish.

Analyses of the health status, risk assessment and recovery response of the nutritionally important catfish Clarias batrachus reared in coal mine effluent-fed pond water: a biochemical, haematological and histopathological investigation

The present field study evaluates the health status of the catfish Clarias batrachus reared in coal mine effluent (CME)-fed pond water at Rajrappa mining complex using biochemical, haematological and histopathological parameters. Simultaneously, risk assessment along with recovery response of the CME intoxicated fish following their treatment with CME-free freshwater was also studied. The CME-fed pond water fish revealed significant decrease in biomolecules concentrations and considerable increase in activities of several enzymes along with metallothionein level as compared to control. The impaired regulation of metabolic function was also revealed by blood parameters showing significant decrease in haemoglobin content (8.78 ± 0.344 g/100 mL) and red blood cells count (1.77 ± 0.12 × 106 mm3) while substantial elevation in white blood cells (187.13 ± 9.78 × 103 mm3). The histopathological study also confirmed the changes including hypertrophy of club cells of skin, swelling of secondary lamella of gills, extensive fibrosis in liver and glomerular shrinkage with increased Bowman's space in kidney. Potential health risk assessments based on estimated daily intake and target hazard quotient indicated health risks associated with the consumption of such fishes. The CME-contaminated fish when transferred to CME-free freshwater exhibited decreased metal content accompanied by eventual recovery response as evident by retrieval in biochemical and haematological parameters. Withdrawal study also revealed restoration in the activity of different marker enzymes in fish tissues including blood as well as recovery in their cellular architecture. The results of the present study validate the depuration process as an effective practice for detoxification of fish contaminated with effluent.

Synergistic Effects Between Dietary Zinc Form Supplementation and Dietary Protein Levels on Performance, Intestinal Functional Topography, Hemato-biochemical Indices, Immune, Oxidative Response, and Associated Gene Expression of Nile Tilapia Oreochromis niloticus

The present study investigates the effect of different dietary protein levels suboptimum level (25%) and optimum level (35%), different Zn forms bulk zinc oxide (BZnO) or nanoparticles zinc oxide (NZnO), and their interaction on performance, intestinal topography, hematology, serum biochemical, antioxidant-immune responses, and related gene expression of Nile tilapia. Six experimental diets were formulated to contain approximately 25% and 35% crude protein and supplemented with Zn forms with 0 (normal level in ingredients), 60 mg kg^-1 BZnO and 60 mg kg^-1 nanoparticles of NZnO. Nile tilapia, Oreochromis niloticus, fingerlings (7.53 ± 0. 06 g) were fed on one of tested diets in triplicates with 5% of total biomass three times a day for 84 days. Results showed that, fish fed diet containing 35% crude protein and supplemented with NZnO form recorded the highest final body weight (FBW), weight gain (WG), and specific growth rate (SGR). However, no significant (P > 0.05) differences were recorded in FBW, WG, SGR, feed conversion ratio (FCR), and protein efficiency ratio (PER) between fish fed diet containing 35% crude protein without Zn supplementation and fish fed diet containing 25% crude protein supplemented with NZnO form. Either fish fed diet containing 25% or 35% crude protein and supplemented with NZnO exhibited the highest values of villi height/width. The highest absorption surface area (ASA) was obtained in fish fed diet containing 25% or 35% crude protein and supplemented with BZnO. Hemoglobin (Hb), hematocrit (Hct), and red blood cell count (RBCs) highest values were obtained for fish fed diet containing protein level 35% supplemented with NZnO. Fish fed diet containing protein level 35% and supplemented with NZnO had the lowest value of alanine amino transferase (ALT) and aspartate amino transferase (AST). The highest globulin value was recorded for fish provided with diet containing 35% crude protein and supplemented with BZnO followed by those fed diet containing 35% crude protein and supplemented with NZnO. Fish fed diet containing protein level 25% with NZnO supplementation recorded the highest super oxide dismutase (SOD), catalase (CAT), glutathione reductase (GSH), and glutathione peroxidase (GP_X), with decreasing malondialdehyde (MAD) values. The highest values of immunoglobulin g (IgG), immunoglobulin M (IgM), complement 4 (C4), and complement 3 (C3) were obtained for diet containing 35% crude protein and supplemented with NZnO form. Growth hormone gene (GH) was upregulated in fish fed 25% dietary protein without Zn supplementation, while it was downregulated in fish fed 25% dietary protein and supplemented with NZnO. Transcription of insulin-like growth factor-1 (IGF-I) gene recorded the highest value for fish fed 35% crude protein and supplemented with BZnO. This is although the diet of 35% crude protein + NZnO induced significant (IGF-I) gene expression compared with 25% crude protein with or without BZnO. Therefore, nano zinc is useful as a feed supplement for Nile tilapia (Oreochromis niloticus).

Fish feed can show genotoxic damage

The present study was carried out to evaluate the genotoxic potential of nutritional quality of feed, using erythrocytic nuclear abnormalities assay in Nile tilapia and its correlation with available nutrients and common fish growth biomarkers. For this, ten feeds commercialized in Brazil were assessed on digestibility and performance assays with triplicate groups. Venipuncture of the caudal vein for abnormalities analyzed was performed 102 days after the fish were fed with the commercial feed twice a day, to apparent satiation. Nuclear abnormalities were analyzed in blood smears. Principal component analysis and correlation matrix were used to carry out an exploratory analysis of correlation between frequency of abnormalities and performance parameters or available nutrients. The frequency of abnormalities in erythrocytes of Nile tilapia, fish performance, and digestibility were feed-dependent. It was observed correlations between the frequency of most abnormalities and performance parameters or content of nutrients. The frequency of kidney-shaped (6.23 ± 4.14), bud nuclei (2.99 ± 1.95), bridge nuclei (0.53 ± 0.50), and binuclei (0.43 ± 0.59) was the highest in fish that also presented the worst performance among all treatments and correlated with digestible methionine. Micronucleus frequency (0.33 ± 0.49) was higher in fish from the same group that presented depressed feed intake and lower available zinc. Only one group presented vacuolated nuclei and the frequency of this abnormality was correlated with available phosphorus. The frequency of abnormalities in erythrocytes is a fish sensitive indicator of health and plays an important role as a complementary tool in the assessment of fish feeding. The variation in the frequency of nuclear abnormalities in erythrocytes obtained among fish fed with the different feeds allows the assertion that they contained genotoxic factors.

Chlorpyrifos and dichlorvos in combined exposure reveals antagonistic interaction to the freshwater fish Mrigal, Cirrhinus mrigala

Toxicity imposed by organophosphate pesticides to the freshwater cultivable fish species mrigal (Cirrhinus mrigala) was assessed under laboratory conditions. Healthy juveniles were exposed to chlorpyrifos, dichlorvos, and their equitoxic mixture in geometric series. Median lethal concentrations of chlorpyrifos were found to be 0.906 (0.689-1.179), 0.527 (0.433-0.633), 0.435 (0.366-0.517) and 0.380 (0.319-0.450) mg/L and dichlorvos were found to be 38.432 (33.625-47.866), 22.477 (19.047-26.646), 12.442 (9.619-14.196) and 11.367 (9.496-13.536) mg/L after 24 h, 48 h, 72 h and 96 h of exposure respectively. Surprisingly, the joint toxicity of these organophosphates in the binary mixture was less than additive during most of the exposure periods. Behavioral changes exhibited by individual as well as mixture pesticide treatments were loss of schooling behavior, aggregating at corners of the test chamber, elevated opercular beatings, surplus mucus secretion, slight color changes and sudden and rapid body movements before death. Loss of fish equilibrium was noticed only in chlorpyrifos treated fish, whereas sluggish behavior was noticed only in mixture pesticide treatment. Such behavioral studies can be applied as a non-invasive bio-monitoring tool for water quality assessment for fish growth and development. Despite the same mode of action of both pesticides, the antagonistic action in the binary mixture is an interesting outcome of this research that requires further investigation for a lucid understanding of the joint toxicity mechanism of such pesticides.

Toxic effects of chlorpyrifos on the growth, hematology, and different organs histopathology of Nile tilapia, Oreochromis niloticus

Chlorpyrifos is a widely applied insecticide that permeates on most waterways and affects aquatic organisms. The growth performances, hematological and histological impacts on Nile tilapia, Oreochromis niloticus following a 60 day of exposure to varying concentrations of chlorpyrifos 20 EC (T₁ 08 µgL⁻¹, T₂ 16 µgL⁻¹, and T₃ 32 µgL⁻¹) were compared to a control T_c 0 µgL⁻¹. The 96-hour LC50 of chlorpyrifos 20 EC was calculated as 46.80 μgL⁻¹. The water quality parameters were recorded regularly. The value of dissolved O₂ and NH₃ stayed rather steady, although temperature varied considerably. It was revealed that as chlorpyrifos levels go up, the percentage of weight gain (WG %), specific growth rates (SGR), and survival rate decreases. The control group T_c had the highest percentages of SGR weight (1.16 ± 0.58) and the T₃ group had the lowest percentages of SGR weight (0.25 ± 0.77). The hematological assessment showed significant differences of hemoglobin concentration, white blood cell counts and red blood cell numbers between chlorpyrifos treatment and control group (P < 0.05). Histological alterations in the liver, gills, and muscle tissues reported to be worse for T₃ as compared to others. There were no statistical differences in GSI, HSI values between control and treatment groups. The chlorpyrifos 20 EC was shown to be highly toxic to O. niloticus at sub-lethal dosages.

Toxicity evaluation and oxidative stress response of fumaronitrile, a persistent organic pollutant (POP) of industrial waste water on tilapia fish (Oreochromis mossambicus)

The study was designed to determine the impact of acute toxicity of fumaronitrile exposure through tissue damaging, oxidative stress enzymes and histopathological studies in gills, liver and muscle cells of freshwater tilapia fish (Oreochromis mossambicus). In gill, liver, and muscle cells, biochemical indicators such as tissue damage enzymes (Acid Phosphatase (ACP), Alkaline Phosphatase (ALP), and Lactate Dehydrogenase (LDH)) and antioxidative enzymes (Superoxide Dismutase (SOD); Catalase (CAT); Glutathione-S-transferase (GST); Reduced Glutathione (GSH); Glutamate oxaloacetate transaminase (GOT) and Glutamate pyruvate transaminase (GPT) were quantified in the time interval of 30, 60 and 90 days exposure to the fumaronitrile. After 90 days, under 6 ppb exposure conditions, the acid phosphatase (ACP) levels of fish increased significantly in the gills (3.439 μmol/mg protein/min), liver (1.743 μmol/mg protein/min), and muscles (2.158 μmol/mg protein/min). After 90 days of exposure to the same concentration and days, ALP activity increased significantly in gills (4.354 μmol/mg protein/min) and liver (1.754 μmol/mg protein/min), but muscle cells had a little decrease in ALP activity (2.158 μmol/mg protein/min). The LDH concentration in gills following treatment with fumaronitrile over a period of 0-90 days was 3.573 > 3.521 > 2.245 μmol/mg protein/min over 30 > 60 > 90 days. However, at the same dose and treatment duration, a greater LDH level of 0.499 μmol/mg protein/min was found in liver and muscle cells. Histopathological abnormalities in the gills, liver, and muscle cells of treated fish were also examined, indicating that fumaronitrile treatment generated the most severe histological changes. The current study reveals that fumaronitrile exposure has an effect on Oreochromis mossambicus survival, explaining and emphasising the risk associated with this POP exposure to ecosystems and human populations.

Toxicological effect of sumithion pesticide on the hematological parameters and its recovery pattern using probiotic in Barbonymus gonionotus

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Sumithion induced hematoxicity and their recovery pattern in Barbonymus gonionotus was measured.

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Sumithion induces severe formation and prevalence of micronuclei and significantly (p< 0.05) increased white blood cells.

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Blood glucose, red blood cell, hematocrit, and hemoglobin were found to be decreased after the exposure of sumithion.

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In recovery experiment, the recovery rate was significantly higher in probiotic treated groups than other treatments.

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Fish micronucleus and hematology is an effective biomarker for toxicity test of an organophosphate.

The experiment was conducted to clarify sumithion induced hematoxicity in silver barb (Barbonymus gonionotus) through in vivo exposures (25 % and 50 % of LC₅₀ of sumithion) and subsequent recovery patterns using normal and probiotic treated feed were also assessed. Three treatments each incorporating three replications were used in the experiment for different days (1, 7, 14, 21, and 28). Treatment T₁ was control (0 mg/L), and two concentrations, such as 2.61 mg/L (25 % of 96 h LC₅₀), 5.21 mg/L (50 % of 96 h LC₅₀) were used as Treatment T₂ and T₃, respectively. After 28 days of exposure to pesticide half of the fishes of T₂ and T₃ were reared in sumithion free water with normal (T₂N, T₃N) and probiotic treated feed (T₂P, T₃P). The median lethal concentration (50 %) for 96 h was 10.42 mg/L. In pesticide-treated groups, values of each hematological parameter (blood glucose, red blood cell, hematocrit, and hemoglobin) decreased but prevalence and severity of micronucleus and white blood cells increased significantly (p< 0.05) with concentration and time duration. Other blood indices including mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) were correspondingly changed in comparison to the control. In the recovery experiment, the silver barb recovered spontaneously, but the recovery rate was significantly higher in probiotic treated groups than normally treated groups in time and duration reliant fashion. In conclusion, persistent sublethal dosages of sumithion caused hematological abnormalities in silver barb. Probiotic supplement can recover the damage but only 28 days of recovery is not enough to recover the total alterations.

Sublethal toxicity of carbofuran in cattle egret (Bubulcus ibis coromandus): hematological, biochemical, and histopathological alterations

This study was aimed to investigate Carbofuran (CF)-induced pathological changes in cattle egret. Two hundred cattle egrets were reared and equally divided into four groups and given different CF concentrations (0.03 mg/L, 0.02 mg/L, 0.01 mg/L and 0 mg/L (control group)). Hematology, serum biochemistry, histopathology, and immunological markers were studied. Our results confirm that CF induces anemic conditions, leukocytosis, elevated liver enzymatic activity, and alterations in renal biomarkers. Moreover, specific microscopic lesions such as multifocal necrosis, pyknotic nuclei, hemorrhages, congestion, and inflammatory cell proliferation were observed in the liver, kidney, spleen, and thymus. These findings suggest that CF can induce harmful effects, so the application of this pesticide in the field must be strictly monitored to mitigate the possibility of exposure to non-target species.

Malathion-Induced Hematoxicity and Its Recovery Pattern in Barbonymus gonionotus

An experiment was conducted to assess malathion-induced hematological responses of Barbonymus gonionotus (silver barb) and its recovery patterns in malathion-free water. Fish (45 days old) were exposed to two sublethal concentrations, namely, 25% and 50% (i.e., 3.78 and 7.56 ppm) of LC₅₀ (15.13 ppm) of malathion for 28 days, followed by a postexposure recovery period for the same time. The hematological parameters were examined after 1, 7, 14, 21, and 28 days of exposure as well as after the postexposure recovery time. Except in the case of the control group (0% of malathion), the obtained results revealed that malathion exposure resulted in significantly (p < 0.05) higher prevalence and severity of micronucleus and lower values of Hb, PCV, and RBC and significantly higher values of WBC in a concentration- and time-dependent manner. The values of blood glucose, MCV, MCH, and MCHC showed mixed trends during the experiment. During the recovery period, all blood parameters (micronucleus, glucose, Hb, PCV, RBC, WBC, MCV, MCH, and MCHC) partially recovered, which means that the recovery period was not long enough for the organisms to recover from the previous exposure. The study thus confirms that hematology is a sensitive indicator for fish to detect toxicity caused by different chemicals. Changes in these parameters can provide useful information about environmental conditions and risk assessment of aquatic organisms.

Determination of Median Lethal Concentration (LC50) for Endosulfan, Heptachlor and Dieldrin Pesticides to African Catfish, Clarias gariepinus and Their Impact on Its Behavioral Patterns and Histopathological Responses

Pesticides such as endosulfan, heptachlor and dieldrin persist in aquatic environments as a result of their resistance to biodegradation. However, there is no adequate information about the toxicity of endosulfan, heptachlor and dieldrin to the aquatic organism, African catfish (Clarias gariepinus)-a high valued widely distributed commercially interesting species. The current experiment was performed with the aim to determine the median lethal concentration (LC50) of endosulfan, heptachlor and dieldrin to African catfish (Clarias gariepinus); their behavioral abnormalities and histopathological alterations in several vital organs. A total of 324 juvenile fish were exposed for 96 h to six concentrations of endosulfan and dieldrin at 0, 0.001, 0.002, 0.004, 0.008 and 0.016 ppm, and to heptachlor at concentrations of 0, 0.02, 0.04, 0.08, 0.16 and 0.32 ppm for dose-response tests. The study demonstrated that the species is highly susceptible to those contaminants showing a number of behavioral abnormalities and histopathological changes in gill, liver and muscle. The 96-h LC50 value of endosulfan, dieldrin and heptachlor for the African catfish was found as 0.004 (0.001-0.01) mg/L, 0.006 mg/L and 0.056 (0.006-0.144) mg/L, respectively. Abnormal behaviors such as erratic jerky swimming, frequent surfacing movement with gulping of air, secretion of mucus on the body and gills were observed in response to the increasing exposure concentrations. Histopathological alterations of liver, gill and muscle tissues were demonstrated as vacuolization in hepatocytes, congestion of red blood cells (RBCs) in hepatic portal vein; deformed secondary lamellae and disintegrated myotomes with disintegrated epidermis, respectively. These findings are important to monitor and responsibly manage pesticide use in and around C. gariepinus aquacultural areas.

Dietary valine improved growth, immunity, enzymatic activities and expression of TOR signaling cascade genes in rainbow trout, Oncorhynchus mykiss fingerlings

This study was conducted to determine the effects of dietary valine (Val) on growth, hemato-biochemical parameters, immunity, enzymatic activities, antioxidant status and expression of target of rapamycin (TOR) and 4E-BP genes in rainbow trout, Oncorhynchus mykiss (1.57 ± 0.03 g; 5.10 ± 0.34 cm). Six isonitrogenous (450 g kg⁻¹) and isoenergetic (20.90 kJ 100 g⁻¹_, gross energy) diets were designed to represent varied Val levels (10.5, 13.0, 15.5, 18.0, 20.5 and 23.0 g kg⁻¹ dry diet basis). Growth parameters improved significantly (P < 0.05) with the amelioration of dietary Val level up to 18.0 g kg⁻¹. Highest (P < 0.05) body protein content was noted at 18.0 g kg⁻¹ dietary Val. Significant differences in hematological, intestinal enzymatic activities and antioxidant parameters were noted. However, plasma variables did not show any significant differences except aspartate transaminase and uric acid. Total protein content increased significantly, while the albumin and globulin content did not show any significant (P > 0.05) difference. Moreover expression of TOR mRNA and elF4E-binding protein (4E-BP) was observed higher (P < 0.05) at 18.0 g kg⁻¹ Val. On the basis of results, optimum dietary Val requirement for maximal growth of rainbow trout was determined to be 18.19 g kg⁻¹ of dry diet, corresponding to 40.42 g kg⁻¹ of dietary protein.

Growth, serum biochemical parameters, salinity tolerance and antioxidant enzyme activity of rainbow trout (Oncorhynchus mykiss) in response to dietary taurine levels

This study evaluated the effect of dietary taurine levels on growth, serum biochemical parameters, salinity adaptability, and antioxidant activity of rainbow trout (Oncorhynchus mykiss). Four diets were formulated with taurine supplements at 0, 0.5, 1, and 2% w/v (abbreviated as T₀, T_0.5, T₁, and T₂, respectively). Rainbow trouts (initial weight of 80.09 ± 4.72 g) were stocked in tanks (180 L capacity), and were fed these diets for six weeks and subsequently underwent salinity acclimation. Physiological indicators were determined before salinity acclimation at 1, 4, 7, and 14 days afterwards. Results showed that there were no significant differences in growth performance (final mean weight ranged from 182.35 g to 198.48 g; percent weight gain was between 127.68% and 147.92%) of rainbow trout in freshwater stage, but dietary taurine supplement significantly increased serum-free taurine content. After entering seawater, the Na⁺-K⁺-ATPase activity of T₂ group returned to its freshwater levels, and the serum cortisol content was significantly higher than T₀ and T_0.5 groups. At the end of this experiment, the liver superoxide dismutase activity in the T₀ and T_0.5 groups was significantly lower than in the T₁ and T₂ groups, and the liver catalase in the T₀ group was the lowest whereas that in the T₂ group was the highest. Muscle malondialdehyde content was the highest in the T₀ group, and the lowest in the T₂ group. Based on the results of this study, supplement of dietary taurine (0.5-2%) enhanced the salinity tolerance in rainbow trout, which increased with the higher taurine concentration.

Assessment of the potential threat of nickel(II) oxide nanoparticles to fish Heteropneustes fossilis associated with the changes in haematological, biochemical and enzymological parameters

The present study has been conducted to evaluate the potential threat of NiO nanoparticles (NiO NPs) on an edible fish Heteropneustes fossilis. Fishes selected for the study were exposed to four concentrations of NiO NPs (12, 24, 36 and 48 mg/l) for the period of 14 days, and various haematological, biochemical and enzymological changes in the exposed fishes were examined. Results revealed that maximum fluctuations were seen in 48-mg/l-exposed fishes when compared with the control in terms of the haematological parameters (RBC count, WBC count, Hb content, Ht% and O₂ carrying capacity of blood), enzymatic activities (AST, ALP, ALT and LDH) and biochemical parameters (level of cholesterol, triglycerides, glucose, total protein, albumin, globulin, bilirubin and creatinine). However, 12 mg/l treatment to the fishes showed its least impact on aforesaid parameters. Furthermore, Ni accumulation and changes in cortisol level in the blood were also noticed in all the treated fishes. Structural changes, such as membrane and nuclear disintegration, micronucleus, deformed and vacuolated cells, and enucleation were also observed in RBCs of NiO NP-treated fishes. Conclusively, our study provides useful information and insight for the possible ecotoxicity of NiO NPs on aquatic organisms and emphasizes upon the importance of treatment of effluents containing nanoparticles before their release into the aquatic system.

Morphometric, hematological and oxidative stress changes in Clarias gariepinus following sub-chronic exposure to tramadol

Tramadol is among the most famous analgesic drugs used for the management, treatment and relief of moderate to severe pain conditions. The present study investigated the effects of tramadol on the behavior, mortality, morphometric, hematology and oxidative stress parameters of C. gariepinus juveniles. The 96 h LC₅₀ value of tramadol determined by probit analysis was 88.76 mg/L. Based on this value, fish were exposed to sublethal concentrations of 4.44, 8.88, 17.75 mg/L tramadol and 0.0 mg/L (control) for the period of 15 days and allowed to recover for 5 days. Fish exposed to tramadol showed some abnormal behavioral responses and mortality increased with increase in the exposure duration and concentrations except for the control. There were variations in hepatosomatic index (HSI) and condition factor (CF) in fish exposed to tramadol. Exposure of C. gariepinus to tramadol elicited reduction in the values of white blood cell (WBC), red blood cell (RBC), hemoglobin (Hb), packed cell volume (PCV) and mean corpuscular volume (MCV) while the values of mean corpuscular hemoglobin (MCH) and the mean corpuscular hemoglobin concentration (MCHC) increased. The values of catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR), reduced glutathione (GSH) and lipid peroxidation (LPO) increased significantly in the exposed fish compared with the control. The values of glutathione peroxidase (GPx) however decreased. The results of the present study demonstrate that tramadol is toxic to fish and its use should be monitored in the aquatic environment.

Assessment of biochemical, hematological and behavioral biomarkers of Cyprinus carpio on exposure to a type-II pyrethroid insecticide Alpha-cypermethrin

This study assessed some important physiological biomarkers of freshwater edible fish Cyprinus carpio following exposure to 10 % (T1) and 20 % (T2) sublethal concentrations of Alpha-cypermethrin (A-cyp) over a total period of 45 days. Behavioral responses were noticed and Kaplan-Meier survival curves were prepared during acute toxicity study. Total serum protein concentration, total erythrocyte count, hemoglobin, packed cell volume, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and total leukocytes count were decreased significantly (p < 0.05), while the blood glucose, total serum lipid concentration, and clotting time were increased significantly (p < 0.05) over control. The most affected fish group and most significantly altered biomarker under toxic stress of A-cyp were identified using integrated biomarker response (IBR). The biomarker response index (BRI) values measured the overall health status of the treated fish and indicated that moderate adverse effects were exerted on the fish group exposed to T2 for 45 days.

Impact of copper and zinc mixture on haematological parameters of rainbow trout (Oncorhynchus mykiss): acute exposure and recovery

Significant changes in composition of rainbow trout Oncorhynchus mykiss blood cells types were induced after 4-days exposure with mixture of Cu²⁺ and Zn²⁺ at 0.25, 0.125 and 0.06 parts of LC₅₀ in comparison to control group. The highest concentration of metal mixture (0.25 of LC₅₀) significantly induced elevation of the number of monocytes and poly-segmented neutrophils. Treatment with 0.125 parts of LC₅₀ concentration increased the number of thrombocytes, monocytes and non-segmented neutrophils. The most diluted mixture resulted in significant induction of thrombocytes, monocytes, non- and poly segmented neutrophils. Analysis of leucocyte cell types in the O. mykiss blood samples after 4-days of exposure at all applied mixture parts showed signs of monocytosis and neutrophilia. Comparison of different types of leucocytes' percentages (leukogram) in fish after 4-days exposure to metal mixture and after 4, 8, and 12-days recovery periods showed that, values of neutrophils even after the 12-days recovery period at all tested parts of LC₅₀, and monocytes after exposure with the highest (0.25) used part of LC₅₀ were not restored to control group levels. Depuration and recovery processes in treated fish are concentration and recovery period dependent.

Distortion of micronuclei and other peripheral erythrocytes caused by fenitrothion and their recovery assemblage in zebrafish

The experiment was explicated to investigate the fenitrothion persuaded genotoxicity in the peripheral erythrocytes of zebrafish (Danio rerio) through in vivo exposures (10 %, 20 % and 40 % of LC50 of fenitrothion, i.e., 0.8, 1.6, and 3.2 mg/L, respectively) for variable periods (1, 3, and 7 days) and its subsequent post-exposure recuperation array in pesticide-free water for similar intervals was also evaluated. With the exception of the control group (0% of fenitrothion), the obtained results pointed out that with the promotion of time and concentrations, fenitrothion induced significantly (p < 0.05) higher prevalence and severity of erythrocytic nuclear abnormalities (ENA) such as- notched, micronucleus, nuclear bridges, blebbed, binucleated, nuclear bud and also erythrocytic cellular abnormalities (ECA) such as - echinocytic, elongated, tear-drop, crescentic, twin, fusion, and spindle-shaped cells. Recuperation data stated that zebrafish cured spontaneously and aberrated erythrocytic anomalies in all treatments were renormalized according to the concentration and duration dependence. Hence, we concluded that fenitrothion has a dangerous effect on the zebrafish, and this technology can be used to anticipate the sensitivity of aquatic animals to environmental pollution.

Adverse effects of atrazine on blood parameters, biochemical profile and genotoxicity of snow trout (Schizothorax plagiostomus)

This study was conducted to evaluate the adverse effects of atrazine on hematology, biochemistry and genotoxicity of snow trout (Schizothorax plagiostomus). Almost all treated groups presented considerably (P < 0.05) lesser values of hematocrit, hemoglobin, WBC, RBC, MCH, MCHC, monocytes and lymphocytes while significantly higher values of HCT and platelets are observed. A Significant decrease is observed in sodium, calcium, potassium, phosphorous, triglycerides, creatinine, urea, and total protein contents whereas, a significant increase is observed in cholesterol and glucose level. Significant (P < 0.05) alterations are observed in enzyme activities of all treated groups. DNA damage was observed at the concentrations (2-4 ppm). Results showed that Comet assay is reliable for evaluating the toxicity and is helpful in environmental monitoring programs.

Influence of IP-injected ZnO-nanoparticles in Catla catla fish: hematological and serological profile

This study reports an effort to synthesize biocompatible zinc oxide nanoparticles using sol-gel method and its influence on hematological and serological profile of Catla catla fish. Hexagonal wurtzite structure and crystallite size of ZnO-NPs was identified by using XRD in the range of 19 to 20 nm. Moreover, the irregular and non-uniform surface of these NPs was found using SEM. The different stretched and vibrational mode (ZnO, OH, CO, and H-O-H) was identified by using FTIR analysis. UV-visible spectroscopy confirmed absorbance of the blue shift in the range 340 nm. Bioassay of ZnO-NPs on Catla catla was performed and nano ZnO was given through intraperitoneal injections at 0, 25, 50, 75, and 100 μg/g body weight doses. Analysis of fish blood samples indicated an increase in WBCs and leukocytes while the differential effect on monocytes. On the other hand in response to varying ZnO concentrations, an increase in RBCs, hemoglobin, and HCT was evident. Serum analysis revealed an increase in urea concentration while a reduction in creatinine, ALT, and AST. In an overall assessment, nano-ZnO supplementation at 25 to 100 μg/g body weight differentially affected hematological and serum biochemical profile of thaila fish. Graphical abstract.

Carbofuran toxicity and its microbial degradation in contaminated environments

Carbofuran is one of the most toxic broad-spectrum and systemic N-methyl carbamate pesticide, which is extensively applied as insecticide, nematicide and acaricide for agricultural, domestic and industrial purposes. It is extremely lethal to mammals, birds, fish and wildlife due to its anticholinesterase activity, which inhibits acetyl-cholinesterase and butyrylcholinesterse activity. In humans, carbofuran is associated with endocrine disrupting activity, reproductive disorders, cytotoxic and genotoxic abnormalities. Therefore, cleanup of carbofuran-contaminated environments is of utmost concern and urgently needs an adequate, advanced and effective remedial technology. Microbial technology (bacterial, fugal and algal species) is a very potent, pragmatic and ecofriendly approach for the removal of carbofuran. Microbial enzymes and their catabolic genes exhibit an exceptional potential for bioremediation strategies. To understand the specific mechanism of carbofuran degradation and involvement of carbofuran hydrolase enzymes and genes, highly efficient genomic approaches are required to provide reliable information and unfold metabolic pathways. This review briefly discusses the carbofuran toxicity and its toxicological impact into the environment, in-depth understanding of carbofuran degradation mechanism with microbial strains, metabolic pathways, molecular mechanisms and genetic basis involved in degradation.

Blood biomarkers of herbicide, insecticide, and fungicide toxicity to fish-a review

Pesticides are widely used in the world agriculture, and they may adversely affect non-target organisms, including fish. The present 2000-2019 literature review summarizes hematological and blood biochemical effects of various herbicides, insecticides, and fungicides in fish. The observed changes usually indicate anemia and inflammation, as well as hyperglycemia, hypoproteinemia, increase in cortisol concentration and activities of hepatic aminotransferases that are typical for intoxication and stress. Other changes that are also sometimes observed such as increase in red blood parameters indicate compensatory response. The often-noted symptoms of immunosuppression show an adverse effect of pesticides on immune system and possible immunosuppression. Pathophysiological changes in fish induced by pesticides depend on many factors, such as active compound and its concentration, exposure duration, fish species, environmental conditions, etc. Hematological and blood biochemical parameters appear to be useful biomarkers for evaluation of physiological state of fish exposed to pesticides; however, they are not specific markers of intoxication.

Transcriptional response of zebrafish larvae exposed to lindane reveals two detoxification genes of ABC transporter family (abcg5 and abcg8)

Lindane is a highly toxic organochlorine pesticide and widely exist in water with harmful effects on fish. Although some genes have been found to be regulated by lindane in fish, the transcriptional response of fish exposed to lindane is still unknown. In this research, the transcriptional changes of zebrafish larvae exposed to 0.2 mg/L lindane from 96 to 120 hpf were studied by RNA sequencing. Our transcriptome identified 554 up-regulated and 118 down-regulated genes and the differentially expressed genes were closely related to the neuromast development, RNA silencing genes, ion transport, and response to estrogen. In addition, we characterized two sensitive and novel lindane-induced ABCG (ATP binding cassette G subfamily) transporter genes- abcg5 and abcg8. Abcg5 and abcg8 genes are located on chromosome 13 of zebrafish and contain 1956/2024 bp open reading frame. The polypeptide deduced by CDS amplification contains 652/676 amino acids and has most of the functional domains and key residues defined in human and mouse ABCG5/Abcg5 or ABCG8/Abcg8. Only when the co-expression of Abcg5 and Abcg8 enable them to transport to the cell membrane surface in 293T cells. In addition, lindane can induce the transcriptional expression of abcg5 and abcg8 genes, and overexpression of Abcg5 and Abcg8 significantly reduced the toxicity of lindane to zebrafish larvae, which means that zebrafish Abcg5 and Abcg8 are potential efflux transporters of lindane. Therefore, these findings provide useful insights for further understanding the zebrafish larvae's transcriptional response and detoxification ability after acute exposure to lindane.

Effects of chlorpyrifos on the crustacean Litopenaeus vannamei

Shrimps can be used as indicators of the quality of aquatic systems exposed to a variety of pollutants. Chlorpyrifos is one of the most common pesticides found in environmental samples. In order to evaluate the effects of chlorpyrifos, adult organisms of Litopenaeus vannamei were exposed to two sublethal concentrations of the pesticide (0.7 and 1.3 μg/L) for four days. The LC₅₀ (96-hours) value was determined and Lipid oxidation levels (LPO) and the activities of catalase (CAT), glutathion peroxidase (GPx), glutathion-S-transferase (GST) were assessed on the muscle, hepatopancreas and gills from the exposed organisms. In addition, inhibition of acetylcholinesterase (AChE) was determined in the brain. LC₅₀ (96-hours) was 2.10 μg/L of chlorpyrifos. Catalase activity and LPO were elevated in the three tissues, whereas a decrease of AChE activities in the brain and an increase of GST activity in the hepatopancreas were observed.

Quercetin-induced amelioration of deltamethrin stress in freshwater teleost, Channa punctata: Multiple biomarker analysis

We aimed to ascertain whether ubiquitous plant-based polyphenolic flavonoid compound quercetin (Q) was capable of alleviating deltamethrin (DM) stress in a freshwater teleost, Channa punctata, with emphasis on levels of acetylcholinesterase (AChE), reduced glutathione (GSH), glutathione-S-transferase (GST), DNA/RNA contents and hematological parameters. We measured these parameters in various tissues of fish at 7 and 21 days of exposure to DM doses (0.03 and 0.15 μL L^-1), Q (0.14 g L^-1) and their combinations (0.03 μL DM L^-1 + 0.14 g Q L^-1 and 0.15 μL DM L^-1 + 0.14 g Q L^-1). Both the DM doses altered blood parameters, lowered DNA/RNA contents, AchE activities, GSH levels and augmented GST activities as a mark of neurotoxicity and oxidative stress in fish tissues. We found that 0.14 g L^-1 Q ameliorated oxidative stress and AchE inhibitory effects, recovered DM-induced nucleic acid damage and alterations in blood parameters, with some tissue specificity and in duration-dependent manner. Thus, the results indicated that Q was capable of neuroprotection and enhancing the function of antioxidants in fish, which could be predicted to be useful for providing better protection to fish under aquaculture settings with improved Q-rich diets. Through this study with multiple biomarkers in several tissues of fish, valuable information for devising better strategies regarding pesticide risk assessment was obtained and it was recognized that an appropriate dose of Q was essential for its better functioning.

DNA damage, acetylcholinesterase activity, and hematological responses in rainbow trout exposed to the organophosphate malathion

Effects of sub-lethal concentrations (0 (control), 0.009, 0.014, and 0.023 ppm) of the organophosphate insecticide "malathion" to rainbow trout (Oncorhynchus mykiss) after the determination of LC₅₀-96 h value (0.093 ppm) were evaluated. Changes in biomarkers of neurotoxicity (acetylcholinesterase (AChE) activity), genotoxicity (DNA damage), and hematological parameters (red (RBC) and white (WBC) blood cell count, hemoglobin (Hb), hematocrit (Hct), mean cell hemoglobin (MCH), mean cell volume (MCV), and mean cell hemoglobin concentration (MCHC)) were assessed for a 15-day exposure. A significant time- and dose-dependent reduction in AChE activities of gill, muscle, brain, and liver tissues was found. However, the AChE activity was less affected by malathion concentration than by exposure time. DNA damage of erythrocytes at different malathion concentrations increased by increasing the experimental time up to the fourth day. A decrease in the count of WBC, RBC, and Hct and an increase in the number of MCH and MCV were observed by increasing malathion exposure dose and time (p < 0.05). An increase in the malathion concentration and exposure time significantly resulted in a decrease in Hb and an increase in MCHC. A significant improvement in AChE activity; DNA damage; and RBC, Hb, Hct, MCV, and MCH indices was detected during a 30-day recovery period, but the WBC count changed insignificantly. The recovery pattern based on 100% water exchange with clean water could be a successful strategy to improve the biomarker responses of rainbow trout habituating in contaminated aquatic environments.

Relationship between arsenic accumulation in tissues and hematological parameters in mullet caught in Faro Lake: a preliminary study

The authors investigated the arsenic (As) accumulation in different tissues (muscle, gill, liver, stomach, and intestine) and the possible correlation between tissue concentration and hematological parameters in mullet (Mugil cephalus Linnaeus, 1758) caught in Faro Lake (Messina, Sicily, Italy). On all fish, hematological analyses of blood samples, measurement of biometric indices, and the removal of the muscles, gills, liver, stomach, and intestine for the determination of arsenic concentration were performed. A hemogram was performed to find effects of arsenic concentration in tissues on hematological variables. One-way analysis of variance showed significant differences of arsenic concentration in different tissues, with higher values in the gill. The correlation between hematological parameters and tissue arsenic concentration showed a statistical significance for red blood cell (RBC), hemoglobin concentration (Hb), and hematocrit (Hct) with the liver As concentration. Biometric indices (weight, length, and fork length) showed a significant correlation with As concentration of the muscle and liver also. Our results indicate the role of some hematological parameters as biomarkers useful to monitoring anthropogenic load of arsenic in water and sediment, because variations of these parameters represent one of the effects that arsenic exposure can have on fish.

Haemato-immunological studies in ZnO and TiO2 nanoparticles exposed euryhaline fish, Oreochromis mossambicus

The present study was aimed to analyze the effect of ZnO and TiO₂ nanoparticles (NPs) on Haemato-immunological parameters in adult Tilapia, Oreochromis mossambicus. The nanoparticles size found as 47 nm and 30 nm for ZnO and TiO₂ respectively. The acute toxicity (96 h) of ZnO (LC50: 100-110 ppm) and TiO₂ (LC50: 80-90 ppm) NPs were identified by using probit analysis. RBC, Hb and HCT levels decreased in nanoparticles exposed groups resulted in decreased oxygen carrying capacity of RBC and other erythrocyte indices (MCH, MCV, MCHC). Increased WBC, neutrophils & monocytes and decreased lymphocyte levels were observed as increased concentration of the nanoparticles. The results were found as statistically significant (p < 0.05). In conclusion, the present study depicts that ZnO NPs exhibits more toxicity than TiO₂ NPs. Nanoparticles presence even in low concentration (ppm) cause damage to the connective tissues of fish, so the existing permissible levels of these nanoparticles in water are need to be revised.

Antioxidant activities of Moringa oleifera leaf extract against pendimethalin-induced oxidative stress and genotoxicity in Nile tilapia, Oreochromis niloticus (L.)

To assess the ameliorative effects of Moringa oleifera (MO) leaf extract on haematological and biochemical changes, liver DNA damage and oxidative stress biomarkers in Nile tilapia (Oreochromis niloticus) exposed to a sublethal concentration (0.52 mg/l) of pendimethalin (PM). Tilapia fish were allocated into four equal groups in tri-replicates as follows: first group was the control group, second group was treated with MO (20 ml/30 l water), third group was exposed to 0.52 mg PM/l and fourth group was exposed to 0.52 mg PM/l and treated with MO leaf extract (20 ml/30 l water) for 28 days. At the end of this period, blood and liver tissue samples were collected and haematological and biochemical changes, hepatic DNA fragmentation and oxidative stress biomarkers were analysed. Pendimethalin caused significant reduction in haematological profile [White blood cells (WBCs) and red blood cells (RBCs) counts, haemoglobin (Hb) concentration and haematocrit (Ht) level]; meanwhile, serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), creatinine, uric acid, glucose, cortisol, cholesterol and lactate dehydrogenase (LDH) were significantly increased. On the other hand, serum total protein, albumin, globulin and acetylcholinesterase (AChE) were decreased. Significant reduction in hepatic superoxide dismutase (SOD), catalase (CAT), total antioxidant capacity (TAC) and glutathione peroxidase (GSH-Px) levels and marked increments of hepatic malondialdehyde (MDA) and DNA fragmentation were observed in PM-exposed fish compared to the control group. The addition of Moringa oleifera leaf extract into the water could overcome the negative impacts of pendimethalin and normalise the examined parameters nearly to the control values. Moringa oleifera was used for the first time to protect tilapia fish against PM-induced toxicity. The present study revealed that Moringa oleifera has potent antioxidant and antigenotoxic actions against pendimethalin toxicity.

Exposure to herbicide linuron results in alterations in hematological profile and stress biomarkers of common carp (Cyprinus carpio)

Phenylurea herbicides such as linuron are commonly applied in agriculture. Common carp juveniles were subjected to 31.5 µg/L of linuron for 14 days, and then to 30 days of purification. Peripheral blood was sampled after 1, 3, 7 and 14 days of exposure and 7, 14 and 30 days of purification and hematological parameters were evaluated: erythrocyte (RBCc) and leukocyte (WBCc) counts, hematocrit (Ht), hemoglobin concentration (Hb), mean cell volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC) and differential leukocyte count. For evaluation of cortisol and catecholamine concentrations blood was sampled after 3, 6 and 12 h, after 1, 3 and 14 days of exposure, and after 30 days of purification. Linuron caused mainly transient increase in RBCc, Ht and MCV values and increase in WBCc and percentage of juvenile neutrophils. The herbicide caused persistant increase of cortisol and catecholamine concentrations. The results indicate that exposure to low concentration of linuron induced a stress response in common carp.

Acute exposure to boron in Nile tilapia (Oreochromis niloticus): Median-lethal concentration (LC50), blood parameters, DNA fragmentation of blood and sperm cells

Recently, Boron (B) contamination of aquatic ecosystem has received considerable critical attention due to its toxic effects at high concentrations on plants as well as animals. Previous studies on toxic effects of B have not dealt with DNA damages in blood and sperm cells of Nile tilapia (Oreochromis niloticus), together with blood parameters. This study consisted of two successive experiments purposes to determine these findings, including the median-lethal concentration (LC₅₀) of B for Nile tilapia. In the first one, at 96 h, LC₅₀ of B for Nile tilapia was 141.42 mg L^-1 B. In the second one, Nile tilapia were treated with five elevated B concentrations (1, 5, 25, 50 and 100 mg L^-1 B) and hematological, serum biochemical parameters, and DNA damages of Nile tilapia in these treatments were determined comparing with the control after 14 days of exposure. Hematological parameters (red blood cell count, hematocrit, and hemoglobin) were similar to each other in all groups while serum biochemical parameters (glucose, total protein, cholesterol, alkaline phosphatase, glutamic oxaloacetic transaminase, and glutamic pyruvic transaminase) in B treatments, especially in 50 and 100 mg L^-1 B groups, were found significantly higher (P < 0.05). DNA fragmentation was detected in all blood cells in ≥25 mg L^-1 B treatments, while all sperm cells in 100 mg L^-1 B treatments. These results demonstrated the harmful effects of B at high concentration (50 and 100 mg L^-1 B) on the DNA integrity of blood and sperm cells, and also the serum biochemical parameters.

Toxicity assessment of cypermethrin nanoparticles in Channa punctatus: Behavioural response, micronuclei induction and enzyme alteration

A comparative toxicity assessment was performed to evaluate the effect of cypermethrin nanoparticles (CypNPs) and cypermethrin (Cyp) on murrel, Channa punctatus. Size variation and shape morphology of nanoparticles were confirmed by scanning electron microscopy, UV-Vis absorption spectroscopy and transmission electron microscopy. CypNPs presented shoulder band at a wavelength of 277 nm and size range between 29.23 nm and 49.28 nm. The individuals of C. punctatus were exposed to two sublethal doses of LC₅₀ viz 1/20th (S₁) of LC₅₀ and 1/10th (S₂) of LC₅₀ of CypNPs (20.54 mg/L) and Cyp (4 μg/L) for 15 days. Micronucleus assay was used to assess the genotoxicity while enzyme activity was evaluated by using alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP). The percentage of micronuclei was increased significantly at different doses in Cyp compared to CypNPs. The AST value of Cyp was significantly different from CypNPs at both doses while ALP level at the S₂ dose (p < 0.05). Increased levels of ALT, AST, and ALP in blood serum caused tissue impairment cellular damage in liver in the fish exposed to Cyp compared to CypNPs which indicated that CypNPs is least toxic than the conventional form of Cyp. AST and ALT also acted as indicators of stress and altered physiological condition in C. punctatus.