Apurba Ratan Ghosh

Biochemical effects of glyphosate based herbicide, Excel Mera 71 on enzyme activities of acetylcholinesterase (AChE), lipid peroxidation (LPO), catalase (CAT), glutathione-S-transferase (GST) and protein content on teleostean fishes.

Effects of glyphosate based herbicide, Excel Mera 71 at a dose of 17.20mg/l on enzyme activities of acetylcholinesterase (AChE), lipid peroxidation (LPO), catalase (CAT), glutathione-S-transferase (GST) and protein content were measured in different tissues of two Indian air-breathing teleosts, Anabas testudineus (Bloch) and Heteropneustes fossilis (Bloch) during an exposure period of 30 days under laboratory condition. AChE activity was significantly increased in all the investigated tissues of both fish species and maximum elevation was observed in brain of H. fossilis, while spinal cord of A. testudineus showed minimum increment. Fishes showed significant increase LPO levels in all the tissues; highest was observed in gill of A. testudineus but lowest LPO level was observed in muscle of H. fossilis. CAT was also enhanced in both the fishes, while GST activity in liver diminished substantially and minimum was observed in liver of A. testudineus. Total protein content showed decreased value in all the tissues, maximum reduction was observed in liver and minimum in brain of A. testudineus and H. fossilis respectively. The results indicated that Excel Mera 71 caused serious alterations in the enzyme activities resulting into severe deterioration of fish health; so, AChE, LPO, CAT and GST can be used as suitable indicators of herbicidal toxicity.

Histopathological alterations in gill, liver and kidney of common carp exposed to chlorpyrifos

Histopathological alterations in gill, liver and kidney of common carp, Cyprinus carpio, intoxicated with sub-lethal concentrations of chlorpyrifos (O,O,-diethyl-O-3,5,6-trichloro-2-pyridyl phosphorothioate) pesticide (1 and 100 μg/L) for a period of 14 days were analyzed under light microscope. Gill exhibited hyperplasia and hypertrophy of gill epithelium, blood congestion, dilation of marginal channel, epithelial lifting, lamellar fusion, lamellar disorganization, lamellar aneurysm, rupture of the lamellar epithelium, rupture of pillar cells and necrosis. Alterations in hepatocytes were more pronounced, including nuclear and cellular hypertrophy, cellular atrophy, irregular contour of cells and nucleus, cytoplasmic vacuolation, cytoplasmic and nuclear degeneration, cellular rupture, pyknotic nucleus, necrosis and melanomacrophages aggregations. Histopathological lesions in kidney were cellular and nuclear hypertrophy, narrowing of tubular lumen, cytoplasmic vacuolation, hyaline droplet degeneration, nuclear degeneration, occlusion of tubular lumen, tubular regeneration, dilation of glomerular capillaries, degeneration of glomerulus and hemorrhage in Bowmans space. The most significant conclusion drawn from this study was that with the increased concentration and duration the toxicosis of chlorpyrifos would be enhanced as shown through the analysis of mean assessment value (MAV) and degree of tissue changes (DTC) also.

Effects of almix herbicide on profile of digestive enzymes of three freshwater teleostean fishes in rice field condition

The present investigation was carried out to compare the alterations of digestive enzymes like amylase, lipase, and protease activities in three teleostean fishes viz., Anabas testudineus, Heteropneustes fossilis and Oreochromis niloticus after application of almix herbicide for 30 days at rice field concentration i.e., 8 g/acre. Highest amylase activity was observed in intestine of A. testudineus (300.76%) and lowest in intestine of H. fossilis (103.89%), while maximum lipase activity was found in stomach of O. niloticus (203.27%) and lowest in stomach of H. fossilis (109.65%). Protease activity was also highest in liver of O. niloticus (270.47%) but lowest in stomach of H. fossilis (114.04%). Changes in the enzymes’ activity were different in respect to fishes and their tissues. According to this analysis, A. testudineus and O. niloticus were more sensitive. So, it can be inferred that long-term exposure of almix even at environment-friendly concentration may cause alterations in the digestive functions.

Histopathological and ultramicroscopical changes in gill, liver and kidney of Anabas testudineus (Bloch) after chronic intoxication of almix (metsulfuron methyl 10.1%+chlorimuron ethyl 10.1%) herbicide

Present study aimed to investigate the effects of almix herbicide on histopathological and ultrastructural changes in freshwater teleostean fish, Anabas testudineus (Bloch) under field and laboratory conditions with a dose of 8 g/acre and 66.7 mg/L respectively for 30 days. In field experiment fish species were reared in special type of cage submerged in pond. Cellular alterations of the concerned organs namely gills, liver and kidney were observed through light, scanning and transmission electron microscopy (SEM and TEM). Gill showed hypertrophy and oedema in secondary gill epithelium, and epithelial lifting under laboratory condition but in field condition hyperplasia was prominent. SEM study revealed necrosis, hyperplasia, excessive secretion of mucus and loss of microridges; while TEM study depicted degenerative changes in mitochondria and chloride cells and severe cytoplsmic vacuolation but the changes were comparatively less under field study. In liver, damage in acinar cells of hepatopancreas, degenerative changes in zymogen granules and detachment of hepatopancreatic acinar cells under laboratory condition were the serious changes, but in field condition fatty deposition is prominent. TEM study depicted dilated, degranulated and vesiculated rough endoplasmic reticulum, dilation and swelling of mitochondria and vacuolation in hepatocytes, but under field condition dilation of mitochondria and appearance of vacuolation were well marked. Kidney showed shrinkage of glomerulus, damaged and hypertrophied proximal convoluted tubule, loss of haematopoietic tissues under light microscopy; while ultrastructural changes like degenerative changes in mitochondria, deformed nucleus, dilation, fragmentation and vesiculation of rough endoplasmic reticulum, severe vacuolation in cytoplasm and necrosis were of very serious concern under laboratory condition, but in field condition epithelial cells showed less damage. Responses depicted that symptoms of lesions were more pronounced under laboratory than field condition and the degree of responses in different tissues were different under these two conditions. Therefore, evaluation of these histopathological lesions in concerned tissues may be established as symptomatic indicators for toxicity study in aquatic ecosystem.

Evaluation of Metabolic Enzymes in Response to Excel Mera 71, a Glyphosate-Based Herbicide, and Recovery Pattern in Freshwater Teleostean Fishes

Metabolic enzymes such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) were evaluated in Indian teleostean fishes, namely, Anabas testudineus (Bloch) and Heteropneustes fossilis (Bloch), for an exposure to 30 days of Excel Mera 71 (17.2 mg/L), a glyphosate formulation, and subsequent depuration under Liv.52, a plant extract at a dose of 187.5 mg/d/250 L for the same period in the same tissues under laboratory condition. ALT activity was significantly increased (P < 0.05) in all the tissues and raised up to 229.19% in liver of A. testudineus (229.19%) and 128.61% in liver of H. fossilis. AST also increased significantly (P < 0.05) and was maximum in liver of H. fossilis (526.19%) and minimum in gill of A. testudineus (124.38%). ALP activity was also raised highly in intestine of H. fossilis (490.61%) but was less in kidney of H. fossilis (149.48%). The results indicated that Excel Mera 71 caused alterations in the metabolic enzymatic activities in fish tissues and AST showed the highest alteration in both the fishes, while lowest in ALP and ALT in A. testudineus and H. fossilis, respectively. During depuration under Liv.52, all the enzyme activities came down towards the control condition which indicated the compensatory response by the fish against this herbicidal stress and it was in the following order: AST > ALT > ALP, in A. testudineus, while H. fossilis showed the following trend: ALT > AST > ALP. Therefore, these parameters could be used as indicators of herbicidal pollution in aquatic organisms and were recommended for environmental monitoring for investigating the mechanism involved in the recovery pattern.

Toxic effects of glyphosate-based herbicide, Excel Mera 71 on gill, liver, and kidney of Heteropneustes fossilis under laboratory and field conditions

The effects of glyphosate-based herbicide Excel Mera 71 under field and laboratory conditions were investigated to evaluate the pathological symptoms through light and electron microscopic study in the gill, liver, and kidney of Heteropneustes fossilis (Bloch) for a period of 30 days. Histological alterations like hypertrophy and fusion in secondary lamellae, damage in chloride cells were more prominent in laboratory conditions under light microscopy. Topological changes such as complete loss of microridges, swelling, and irregular arrangement of microridges in the gills were prominent under scanning electron microscopic study under laboratory conditions. Transmission electron microscopy (TEM) study depicted vacuolation and degeneration in chloride cells, dilation in rough endoplasmic reticulum (RER), and mitochondria in gill epithelium. The liver showed enlarged and pyknotic hepatocytes, vacuolation, excess fat deposition, and necrosis under laboratory conditions, while enlarged acentric nuclei, increased sinusoidal space, and less vacuolation in cytoplasm were observed under field conditions. TEM displayed cytoplasmic vacuolation and a reduced number of endoplasmic reticulum and glycogen droplets in the laboratory, but this was less pronounced under field conditions. In the kidneys, loss of hematopoietic tissue, degenerative changes in glomeruli, proximal and distal convoluted tubule, and epithelial cell lining of the renal tubules were comparatively less prominent under field conditions. Under TEM, epithelial cell necrosis, endoplasmic reticulum fragmentation, and mitochondrial degeneration were more prominent under laboratory conditions. The present study evaluated the comparative toxicity under field and laboratory conditions under long-term exposure to glyphosate herbicide and identified pathological responses as indicators in monitoring the herbicidal contamination in aquatic ecosystems.

A scanning electron microscopic probe into the cellular injury in the alimentary canal of Notopterus notopterus (Pallas) after cadmium intoxication.

Microanatomical changes attributable to cadmium poisoning have been observed in the various regions of the alimentary tract of Notopterus notopterus after exposure to sublethal concentrations (75.54 mg CdCl2 liter-1) of the metal. In the buccopharynx, the major changes following treatment with cadmium were shrinkage of the stratified epithelial cells with shriveling of the microridges and loss of lateral contacts between neighboring epithelial cells. But the most pronounced effect was the aggravated secretion of mucin. The damage to the round or oval stratified epithelial cells in the esophagus was manifested by formation of an even sheet of microridges. In the stomach, the most conspicuous changes were the patchy necrosis of the columnar epithelial cells, fragmentation of microridges, and vigorous secretion of mucus from the apical portion of epithelial cells. Owing to cadmium treatment intestinal ceca exhibited disrupted mucosal folds with loss of the normal rectangular box-shaped arrangement. The columnar epithelial cells were found to lose their regular arrangement with an irregular positioning of the microridges within the cells after cadmium exposure. The mucosal folds of the anterior intestine became intensively disrupted with appreciable damage to the columnar epithelial cells. In the middle intestine the surface epithelial cells were adversely torn and the microvilli of the epithelial cells facing the lumen were heavily damaged. After cadmium exposure accelerated mucous cell activity in the intestine was distinct. No conspicuous changes were observed in the rectal portion after cadmium exposure, except for the disintegration of columnar epithelial cells and a concomitant release of large amounts of mucus into the lumen. All these findings suggest impaired digestion and absorption through the alimentary tract of the aforementioned fish.

Histopathological and Ultrastructural Alterations in Anabas testudineus Exposed to Glyphosate-Based Herbicide, Excel Mera 71 under Field and Laboratory Conditions

Present study aimed to investigate the effects of glyphosate-based herbicide, Excel Mera 71 on histopathological and ultrastructural changes in freshwater teleostean fish, Anabas testudineus (Bloch) under field (750 g/acre) and laboratory (17.20 mg/l) conditions for 30 days. In field experiment, fish were reared in special type of cage submerged in pond. Cellular alterations in stomach and intestine were observed through light, scanning and transmission electron microscopy (SEM and TEM). Lesions at the cellular and subcellular levels under field and laboratory conditions were compared. Responses under light microscopy depicted that the symptoms of lesions were more pronounced under laboratory condition than field. Ultrastructural examination also confirmed the observations through SEM and TEM study and the degree of responses in concerned tissues were different under these two conditions. Therefore, evaluation of these histopathological lesions in the concerned tissues may be established as symptomatic indicators for toxicity study in aquatic ecosystem.

Effects of Almixî Herbicide on Oxidative Stress Parameters in ThreeFreshwater Teleostean Fishes in Natural Condition

Background: Aquatic pollution by pesticidal application, in recent times, has gained much attention throughout the world, as they ultimately reach to the aquatic bodies through agricultural runoff or by aerial spraying and finally, impair the health status of fish. The aim of the present study was to evaluate the toxicological responses of Almix® herbicide on oxidative stress parameters in three Indian freshwater teleosts namely, Anabas testudineus, Heteropneustes fossilis and Oreochromis niloticus in natural condition. Methods: Almix® herbicide was applied at field concentration (8 g/acre) used for rice cultivation to evaluate the oxidative stress responses in freshwater teleostean fishes for a period of 30 days. Special type of cage was installed in pond for culturing the fish species. Results: Acetylcholinesterase (AChE) activity was increased significantly in all fish tissues (p<0.05) and highest enhancement was observed in spinal cord of A. testudineus, but minimum activity was observed in spinal cord of H. fossilis. Significant increased (p<0.05) lipid peroxidation (LPO) level in all tissues was observed after Almix® exposure; highest in muscle of O. niloticus and lowest in brain of H. fossilis. Catalase (CAT) activity also showed significant enhancement (p<0.05), and was maximum in gill of O. niloticus and minimum in liver of O. niloticus, while glutathione-Stransferase (GST) activity was reduced significantly in liver (p<0.05), and in particular, highest reduction was observed in case of H. fossilis. Protein content also showed significant reduction (p<0.05) after Almix® exposure in all fish tissues. Conclusion: Long-term exposure of Almix® herbicide even at environment friendly concentration caused significant induction on oxidative stress parameters and these responses could be considered as useful tools for monitoring herbicidal contamination in freshwater ecosystem.

Histopathological Study in Stomach and Intestine of Anabas testudineus (Bloch, 1792) under Almix Exposure

The aim of the present study was to investigate the histopathological alterations in the stomach and intestine of Indian freshwater teleost, Anabas testudineus (Bloch, 1792) after Almix® exposure both under laboratory and field conditions. The field (dose 8 g/acre) and laboratory (dose 66.67 mg/l) experiments was carried out for 30 days. Special type of cage was prepared and installed in the pond for the field experiment. Pathological alterations in the concerned fish organs namely stomach and intestine were assessed through light microscopy, scanning and transmission electron microscopy. Lesions observed under light microscopy also endorsed the findings of ultrastructural observations both under laboratory and field conditions. Cytopathological alterations observed under light and electron microscopy revealed that the degree of responses were different in different fish tissues as well as under conditions, here in particular effects in stomach were more prominent in laboratory condition. The overall responses registered in the fish tissues under laboratory condition were more pronounced than field condition. Therefore, these symptoms and/or alterations in the present study due to almix intoxication could be considered as biomarkers in toxicity study in aquatic ecosystem.