Alterations in liver marker enzymes and recovery ability of cyprinids as indicators of aquatic pollution.

Information on the detection of pesticides in fresh water Lakes of Kashmir (Dal and Mansbal) through GC-MS technique is scarce, and also the recovery in biochemical parameters (AST, ALT and ALP) of fish after transferring them to clean media has not been reported yet. The water samples were collected from three sites and analyzed for their pesticide profile by dispersive liquid-liquid micro extraction (DLLME) followed by GC-MS. Influence of pesticides on liver marker enzymes of Cyprinus carpio and Carassius carassius was also investigated. The results obtained showed the presence of three main pesticides viz. chlorpyrifros, dimethoate and dichlorvos in waters of Dal Lake whereas no pesticide was detected in waters of Mansbal. The higher values for AST, ALT and ALP activities and decrease in protein content were obtained in the samples from the Dal Lake compared with those from Mansbal Lake (p < 0.05). These data when compared with the values found in C. carpio and C. carassius from both the Dal Lake and Mansbal Lake kept under laboratory conditions after 15, 30, 45 and 60 days of maintenance in clean media found that during depuration, all the enzyme activities came down significantly (p < 0.05) indicating the compensatory response by the fish against the pesticide stress. Therefore, these parameters could be used as indicators of pesticide pollution in aquatic organisms and were recommended for environmental monitoring for investigating the mechanism involved in the recovery pattern.

Dimethoate Induced Behavioural Changes in Juveniles of Cyprinus carpio var. communis under Temperate Conditions of Kashmir, India.

The present study was designed to investigate acute toxicity of dimethoate on juvenile Cyprinus carpio var. communis. Fishes weighing 10 ± 2 gms were selected and mortality data was statistically evaluated by Finney's Probit Method. The 96-hour LC50 value for Cyprinus carpio was found as 1.1 ppm in static bioassay system. Mean values of physicochemical parameters of aquarium waters determined during bioassay depicted slight variation indicating that the mortality in aquarium fishes occurred due to pesticide exposure and not suffocation. Lab. temperature ranged from 12 to 13°C; water temperature ranged from 11 to 12°C; dissolved oxygen ranged from 3.90 to 4.56 mg/L; pH ranged from 6.90 to 7.05; total dissolved solids ranged from 2.66 to 3.0 × 10(3) mg/L, while CO2 remained at a constant value of 2.0 mg/L. The fishes elicited various behavioural responses such as uncoordinated movements, convulsions, excessive mucus secretion, and imbalanced swimming which ended in a collapse to the bottom of the aquarium. Prior to death, the clinical signs like scale erosion, pale body colour, and hemorrhagic patches over the body were noticed which became more vivid up to the termination of experiments. Results of the study indicate potential toxicity of dimethoate in fingerlings of common carp for which the natural waterbodies must be continuously monitored to reduce its impact across food chains.

Complete mitochondrial genome organization of Schizothorax esocinus (Heckel, 1838).

The complete mitochondrial genome of Schizothorax esocinus, an endemic coldwater fish of Himalayas, was determined for the first time. The genome is 16,583 bp in length and consists of 13 protein-coding genes, 22 tRNAs, 2rRNA genes and 1 putative control region. The gene organization and its order were similar to other vertebrates. The overall base composition was; A 29.8%, G 17.8%, C 27%, T 25.4%, A + T content 55.2% and the G + C content 44.8%. The control region was also consisted of a microsatellite locus (TA) 13 between 16,463 to 16,488 bp. The present study will provide the rationale for the management and conservation of S. esocinus.

Complete mitochondrial genome organization of Schizopyge niger (Heckel, 1838).

The complete mitochondrial genome of Schizopyge niger, an endemic coldwater fish of Himalayas was determined for the first time. The genome is 16,585 bp in length and consists of 13 protein-coding genes, 22 tRNAs, 2rRNA genes and 1 putative control region. The gene organization and its order were similar to other vertebrates. The overall base composition was; A: 29.9%, G: 17.7%, C 27.1%, T 25.3%, A + T content 55.2% and the G + C content 44.8%. The control region was also consisted of a microsatellite locus (TA)13 between 16,471 to 16,496 bp. The present study will provide the rationale for the management and conservation of S. niger.

Complete mitochondrial genome organization of Schizothorax labiatus (McClelland, 1842).

The complete mitochondrial genome of Schizothorax labiatus, an endemic coldwater fish of Himalayas was determined for the first time. The genome is 16,582 bp in length and consists of 13 protein coding genes, 22 tRNAs, 2rRNA genes and one putative control region. The gene organization and its order were similar to other vertebrates. The overall base composition was; A: 29.8%, G: 17.7%, C 27%, T 25.5%, A+T content 55.3% and the G+C content 44.7%. The control region was also consisted of a microsatellite locus (TA)12 between 16,467 and 16,490 bp. The present study will provide the rationale for the management and conservation of S. labiatus.