Haematotoxic effect of linear alkyl benzene sulphonate (LAS) in fish,Heteropneustes fossilis

It was observed that clotting time decreased with the increased concentrations of LAS. However, the decrease was more pronounced at LC50 for 24 h and at the end of 96 h LC50, it was very close to control values.     

Impact of linear alkyl benzene sulphonate (LAS) on phosphatase activity in testis of the teleostean fish,Heteropneustes fossilis (Bloch)

Fishes are sensitive indicators of pollutants present in water.These pollutants cause various physical and physiological alterations in fishes. In the present work alteration in the activity of acid and alkaline phosphatase was evaluated in testicular tissue of fresh water fish Heteropneustes fossilis exposed to LC50 value of linear alkyl benzene sulphonate (LAS) for different exposure periods [24 h, 48 h, 72 h and 96 h] With increase in the concentration of chemical LAS, the activity of acid phosphatase (ACP) was reported elevated while a significant fall in the activity of alkaline phosphatase (ACP) was recorded for same exposure period. Elevated activity of ACP, one of the important hydrolases of lysosomes, is quite suggestive of bringing about gross necrosis and dysarchitecture. ALP is involved in various metabolic activities including gonadal maturation and as such decreased activity of this enzyme is definitely one of the important causative factors for reproductive impairment of the fish.     

Effect of linear alkyl benzene sulphonate on erythrocyte sedimentation rate of teleost fish,Heteropneustes fossilis

ESR increased at all concentrations and exposures to LAS. However, increases were more pronounced at LC50 for 24 h and minimum at the end of 96 h.     

Histopathological changes in liver of Heteropneustes fossilis exposed to cypermethrin

Cypermethrin was administered to Heteropneustes fossilis in chronic concentration to determine lesion of liver as indicators of tissue damage. The cypermethrin dose used was 1/4 of 96 hr LC50. Histopathological changes in liver ranged from vacuolization, necrosis, fibrosis of perivascular region and disposition of yellow brown grains at different time of exposure viz; 20th, 30th, 40th and 60th days.     

Alterations in serum electrolyte levels after dimethoate exposure and recovery in the freshwater air-breathing catfish,Heteropneustes fossilis (Bloch)

Dimethoate, a moderately toxic insecticide, has a wide range of agricultural and domestic applications. Like other organophosphates, dimethoate has anticholinesterase activity. Fish are non-target organisms, inadvertently exposed to pesticides and their metabolic products. The present study includes short-term (96 h) and long-term (36 d) effects of dimethoate exposure on some serum electrolytes Ca²⁺, Mg²⁺, and Pi in the freshwater air-breathing catfish Heteropneustes fossilis. The concentration of dimethoate for short-term exposure was 2.24 mg L^?1 (75% of 96 h LC₅₀) and for long-term exposure 0.75 mg L^?1 (25% of 96 h LC₅₀). The study includes the recovery pattern in serum electrolytes after placing the fish in pesticide-free water. Fish show hypocalcemia, hypermagnesemia, and hyperphosphatemia after short-term and long-term exposure to dimethoate. When placed in pesticide-free water, these electrolytes exhibit recovery towards normalization, indicating significant (p < 0.05) recovery.     

Behavioural changes in freshwater fish, Cirrhinus mrigala (Hamilton) exposed to cypermethrin

The toxicity of insecticide cypermethrin to the freshwater fish, Cirrhinus mrigala was studied using static bioassay method. The 96 h LC50 was found to be 5.13 microg/l. Increase in opercular movement, loss of equilibrium, increase in surface behaviour, change in body colour, increase secretion of mucus, irregular swimming activity, rapid jerk movement, 'S' jerky, partial jerk, and aggressiveness were observed in fish exposed to lethal concentration of cypermethrin. But in sub lethal concentration changes were observed from that of lethal and with the approach of 14 and 21 day, fish attained to normalcy.     

Bioaccumulation of cobalt,digestive enzyme activities,and growth of freshwater catfish,Heteropneustes fossilis (Bloch), fed cobalt-supplemented diets

Experiments were conducted to determine the effects of excess dietary cobalt (Co) on its bioaccumulation, on digestive enzyme activities, and on the growth of freshwater catfish Heteropneustes fossilis (Bloch). Four isonitrogenous diets (average crude protein: 32.7%) were formulated to prepare a control diet (T1) with no Co, and three Co-supplemented diets with 0.05 (T2), 0.1 (T3), and 1.0 (T4)% Co. The results showed that H. fossilis fed with T3 diet showed maximum apparent protein digestibility, feed conversion, protein utilization, and growth. Protease and lipase activities were also maximum in T3 diet. Accumulation of Co in different soft and hard tissues of the fish did not show any correlation with the level of Co in the diet. The concentration of Co in the water increased with its dietary level, being at an alarming level at 1.0% dietary Co. It is concluded that an additional supply of dietary Co up to a level of 0.1% is a viable option to augment growth of the catfish H. fossilis, but at higher levels of Co it may be detrimental to the fish and the aquatic ecosystem.     

Impact of endosulfan on the profiles of phospholipids at sublethal concentration in the male Heteropneustes fossilis (Bloch)

Male Heteropneustes fossilis were exposed for 30 days at sublethal concentration (0.002 ppm) during different phases of its annual reproductive cycle. Its impact on total phospholipids (TP), phosphatidylcholine (PC), phosphatidylserine (PS), phosphatdylinositol (PI) and phosphatidylethanolamine (PE) were measured in liver, plasma and testes. During preparatory phase, in general, the levels for TP, PC, PS, PI and PE decreased after endosulfan exposure in the above tissues. During prespawning and spawning phases, the phospholipids also showed decreasing trend. The postspawning phase, exhibited decline in hepatic levels of PS and PI only and remained unaffected in the other two tissues. During the resting phase too, the hepatic levels of TP, PS and PI declined and remained unaltered in others. The present results indicate that endosulfan have very selective effects on phospholipids classes during different phases of the annual reproductive cycle interfering with the production of lipid deprived energy i.e. vitellogenin. In general, endosulfan has inhibitory role during reproductive growth affecting phospholipid biosynthesis via hepatic enzyme systems as well as by hormonal imbalance.     

Devicyprin induced gonadal impairment in a freshwater food fish, Channa punctatus (Bloch)

Synthetic pyrethroids are the recent major class of broad spectrum, photostable, organic insecticides used in agricultural, domestic and veterinary applications and now account for more than 30% of global insecticide use. Cypermethrin is metabolized and eliminated significantly more slowly by fish than by mammals or birds, which may explain this compound's high toxicity in fish compared to other organisms. The present communication deals with histoanatomical alterations in the gonads of a local fresh water food fish, Channa punctatus exposed to 0.033 ppm (96 hr LC50 X 1/10) concentration of a synthetic pyrethroid, devicyprin (cypermethrin 25%) in aquatic medium of aged tap water for 15, 30 and 45 days respectively. In testis, exposure dependent histological damage has been observed in terms of vacuolization, condensation of spermatogonic cells, distortion of tubular epithelium, shrinkage of interstitial cells and general inflammatory responses. Longest exposure of 45 days has resulted in peculiar starry-sky appearance of the testicular tissue. Gross histo-anatomy of ovarian tissue reveals epithelial lesions, inflammatory responses, stromal hemorrhage, increased interstitium and shrinkage of yolk vesicles towards periphery These findings are quite suggestive of reproductive impairments leading to delayed gonadal maturity and adversely affecting processes of sperm production and ovulation and thus, the fish production.     

Influence of a botanical pesticide,azadirachtin, on ultimobranchial gland of the freshwater catfish Heteropneustes fossilis

Freshwater catfish, Heteropneustes fossilis, were subjected to 42 mg L^?1 of azadirachtin for short-term exposure (96 h) and to 10.5 mg L^?1 for long-term exposure (28 days). Six fishes were sacrificed on each time interval from control and experimental groups after 24, 48, 72, and 96 h in the short-term exposure and after 7, 14, 21, and 28 days in the long-term experiment. The calcium regulating endocrine gland, viz. the ultimobranchial gland, was fixed for histological studies. Up to 72 h of azadirachtin treatment, there was no histological alteration in the UBG (ultimobranchial gland) of H. fossilis. After 96 h exposure, the ultimobranchial cells stain feebly and the nuclear volume of these cells were slightly decreased. No histological alterations have been observed in the UBG cells up to 14 days following azadirachtin exposure. After 21 days, the cytoplasm of ultimobranchial cells was feebly stained and the nuclear volume exhibits a decrease. The nuclear volume of these cells was further decreased and the gland shows vacuolization and degeneration at certain places after 28 days azadirachtin treatment. Hence, it can be concluded that azadirachtin severely affects the physiology of calcium homeostasis in H. fossilis. Therefore, the botanical pesticides should be used carefully near aquatic reservoirs.     

Fecundity of the freshwater fish Channa punctatus (Bloch) from three aquatic bodies

The fecundity studies on Channa punctatus revealed that there is a relationship between length of the fish with fecundity, weight of the fish and ovary with fecundity. The length and fecundity exhibit curvilinear relationship and a straight line relationship is observed between fecundity and body weight. Fecundity and ovary weight also exhibited linear relationship. The comparative degree of fecundity of the fish is Jagat tank > Kadaganchi tank > Kagina river. Although fish collected from Jagat tank exhibits higher fecundity, all the other three aquatic bodies provide proper environmental conditions for the growth and reproductive activity of the fish.     

Effect of pH and salinity on pathogenicity of Flavobacterium columnare and Myxobacterium sp. in Indian cat fish, Clarias batrachus (Linn.) and Heteropneustes fossilis (Bloch.)

Flavobacterium columnare (FC) and Myxobacterium sp. recorded persistently associated in fish hatchery and culture system of Himalayan and Sub - Himalayan regions were found to be pathogenic. The pH and salinity played a significant role on the pathogenicity of these potent pathogens in case of Clarias batrachus and Heteropneustes fossilis. LD50 value of FC was 10(4.5) CFU in both the fishes and those of Myxobacterium sp it was 10(6) CFU ml(-1) fish(-1). Fish challenged with F. columnare and Myxobacterium sp. (@ 0.2 ml fish(-1)) individually consisting 10(5-6) cfu ml(-1) exhibited explicit symptoms of columnaris disease and marked with ulceration and saddle back lesion on the dorsal side of body. Maximum reisolation of inoculated bacteria was recorded at pH 7.0 and 7.5 and at 0.0-0.5 (F. columnare) and 0.0-1.0% (Myxobacterium sp.) salinity. Foregoing results elucidated that F. columnare was more sensitive to salinity in comparison to Myxobacterium sp. and their pathogenicity significantly (p<0.05) depends on the salinity and pH that might be one of the physical factors to control their proliferation.     

Histopathological alterations in hepatopancreas of Gafrarium divaricatum exposed to xylene, benzene and gear oil-WSF

Gafrarium divaricatum were exposed to xylene (4.25 and 8.50 mg l(-1)), benzene (4.35 and 8.70 mg l(-1)) and gear oil-WSF (1 and 2%) for 30 days. Chronic exposure of clams to the pollutants resulted in loss of bubbling epithelium, reduction in cytoplasm volume and density, fusion of cell membranes and nuclei forming darkly stained area at basal part of the cells. Disintegration of basement membrane due to damaged epithelial cells, disruption of inner lining of tubule, formation of necrotic spaces, separation of epithelial cells from basement membrane, increase in internal luminar area, complete necrosis of epithelial cells as well as occurrence of cell debris in between the tissue were also observed in the clams due to chronic exposure of the toxicants.     

Effects of estradiol-17beta and 17alpha, 20beta-dihydroxy-4-pregnen-3-one on different phospholipids metabolism and histological changes in ovary during reproductive growth in the catfish, Heteropneustes fossilis (Bloch)

Effect of cumulative doses of estradiol -17beta (E2-7, 14 and 28 mg/kg body weight) and 17alpha, 20beta-dihydroxy-4-pregnen-3-one (17alpha,20betaP-7, 14 and 28 mg/kg body weight) on total phospholipids (TP) and various phospholipids- phosphatidylcholine (PC), phosphatidylserine (PS), phosphatidylinositol (PI) and phosphatidylethanolamine (PE) on liver plasma and ovary were investigated during the reproductively active preparatory and prespawning phases of the annual reproductive cycle in the freshwater female catfish, H. fossilis. The effect of E2 on TP was generally stimulatory and has pronounced effect than 17alpha,20betaP during both the phases. The levels of PC was promoted high during prespawning phase by E2 comparatively very less than by 17alpha, 20betaP in studied tissues during both the phases. The levels of PS after E2 treatments was maximum in all tissues during prespawning phase whereas 17alpha,20betaP was effective only in liver during this phase. The PI was elevated in liver during preparatory phase but its elevation was in all studied tissues during prespawning phase after E2 treatments. The levels of PI was most effective in ovary during preparatory phase in response to 17alpha,20betaP. The levels of PE was declined in liver but elevated in ovary after E2 treatments during both the phases. Treatments of E2 during preparatory phase showed greater number of vitellogenic oocytes as compared to 17alpha,20betaP treatments. The present finding has demonstrated that estradiol-17beta has more pronounced effects than the 17alpha,20beta P in regulation of different phospholipids and ovarian recrudescence during reproductively active phases and among the phospholipids the PC is the main phospholipids of vitellogenin/ovarian lipids in H. fossilis.     

Development and growth of eggs and larvae of Mytilus edulis exposed to a linear dodecylbenzenesulphonate,LAS

The fertilization and growth of eggs and larvae of Mytilus edulis L. were studied under the influence of an important ingredient in washing powders, linear dodecylbenzenesulphonate (LAS). Observable effects occurred in concentrations as low as 0.05 ppm. The length attained by the larvae was affected even by concentrations of 0.1 ppm. The possible ecological consequences of these effects are discussed.     

Haematological responses to exposure to sublethal concentration of cadmium in air breathing fish, Channa punctatus (Bloch)

The effect of sublethal concentration (29 mg/l) of cadmium on haematological parameters of Channa punctatus after the exposure periods of 7, 15 and 30 days were studied. In treated groups of cadmium exposed fish have been found to significantly decreased in total erythrocyte count, haemoglobin content, packed cell volume, mean corpuscular haemoglobin concentration and oxygen carrying capacity of blood, and at the same time the white blood cell count, mean cell volume and mean corpuscular haemoglobin were found to significantly increased. Both increasing and decreasing of the above mentioned haematological characteristics of blood cells of cadmium intoxicant are mainly with time dependent effects. With regard to the pathological characteristics of blood cells of cadmium intoxicant fish shows fragility and rupture of erythrocytic membrane and leads to haemolysis, which are very severe on 30 day of exposure group.     

Growth inhibition and DNA damage in the earthworm (Eisenia fetida) exposed to perfluorooctane sulphonate and perfluorooctanoic acid

An artificial soil method was applied to study the effects of perfluorooctane sulphonate (PFOS) and perfluorooctanoic acid (PFOA) on earthworms (Eisenia fetida). Survival, growth inhibition and damage to DNA of earthworms were detected after 14 d acute exposure. The 14 d-LC₅₀ of PFOS and PFOA was 478.0?mg·kg^?1 dw and 759.6?mg·kg^?1 dw, respectively, indicating that they were of low toxicity. Both PFOS and PFOA could significantly inhibit the growth of earthworms after 14 d exposure, and growth inhibition rates increased with the greater concentrations of PFOS or PFOA, showing a dose–response relationship (PFOS: r?=?0.951, P r?=?0.962, P?P?50 of PFOS was lower than that of PFOA, the growth inhibition rate of earthworm exposed to PFOS was higher than that exposed to PFOA at the same concentration level, and the median values of TL, CL and OTM in PFOS treatments were also higher than those in PFOA treatments. In conclusion, both these fluorine compounds were moderately toxic to earthworms, but the PFOS effect was greater than that of PFOA.     

Alterations in plasma electrolyte levels of a freshwater fish Cyprinus carpio exposed to acidic pH

The impact of acidification (Low pH 5.0) on plasma electrolytes (Na⁺, K⁺, Cl^?, Ca²⁺, and Mg²⁺) in a freshwater fish Cyprinus carpio was studied for a 35 day (long term) exposure period, while control groups were maintained at neutral pH (7.3). During long-term (35 days) exposure periods, plasma K⁺ and Mg²⁺ levels were increased (77.8% and 16.0%) in the low pH (5.0) treated fish. On the other hand, plasma Na⁺, Cl^?, and Ca²⁺ levels were decreased (12.4%, 18.4% and 31.3%, respectively). The loss of plasma Na⁺, Cl^?, and Ca²⁺ indicates the displacement of Ca²⁺ from tight junctions. The increased plasma K⁺ ion might have resulted from acidosis, because intracellular K⁺ is released from muscle as H⁺ enters. The elevated level of plasma Mg²⁺ might be due to inhibition of active transport of magnesium across the kidneys resulting in the accumulation of this ion in the plasma. Ionic alteration takes place upon exposure to acidic pH and can be considered as a potential tool for detecting environmental stresses caused by acidification.     

Observations on the histological alterations in various tissues of EUS affected fish, Channa striatus (Bloch)

Histopathological investigations have been made on the skin, liver, kidney and intestine of, (EUS) affected fish, Channa striatus and following anomalies have been observed. Varying degree of degeneration has been observed in the epidermis, dermis, hypodermis and underlying musculature. In all the cases, the skin lost the scales and epidermis completely at the site of infection. The dermis along with hypodermis showed the signs of necrosis. Necrosis also took place in subcutaneous layer underlying the hypodermis. Necrotization and formation of granulomas can clearly be seen in circular and longitudinal muscle layers. The liver exhibited the loosening of tissue and distension in cell bodies. While in case of kidney, shrinkage took place in all the components. Similarly, the intestinal villi got necrotised alongwith their constituent elements.     

Growth inhibition in Japanese medaka (Oryzias latipes) fish exposed to tetrachloroethylene

A recent study in our laboratory has demonstrated that tetrachloroethylene (TCE) is acutely toxic to Japanese medaka (Oryzias latipes) larvae with a 96 hr-LC50 of 18 (17-19) mg/mL (Spencer et al., 2002). In the present study we hypothesize that TCE exposure induces a developmental effect in Japanese medaka. Growth and age specific sensitivity of Japanese medaka larvae were studied with four age groups (7, 14, 21 and 28 days old) to determine tetrachloroethylene effects on these parameters. The medaka larvae were exposed for 96 hours in a single concentration (10 mg/mL) of TCE. The toxic endpoints evaluated were larvae weight, length, water content and protein concentration. The study revealed that exposure of medaka larvae to this sub-acute concentration of TCE significantly reduced length and weight in the treated group. The difference in growth between control and treated groups was more obvious in age versus length, than in age versus weight. The dry weight-fresh weight ratio (dw/fw) was shown to be higher in the control group. Water content in TCE-treated medaka was higher than in the control group, and younger fry had more water content than older ones. A higher protein concentration was also observed in TCE-treated medaka compared to the control group. These results indicate that TCE has a profound effect on the growth and development of Japanese medaka larvae.