جستجوی مقالات مرتبط با کلیدواژه « سموم کشاورزی » در نشریات گروه « شیلات »

Agricultural pesticides are important chemical pollutants which are extensively used worldwide. In this study, the effects of sub-lethal concentrations of Chlorpyrifos were investigated on haematological parameters of Grass Carp. In the present experiments, first the lethal concentration (LC50) of Chlorpyrifos was calculated, then the effects of different concentration of LC50 (10, 20 and 30 %) were studied on cortisol, glucose, RBC, hematocrit, hemoglobin, WBC and some other blood factors of Grass carp (C. idella) during 14 days. Blood sampling was performed at 12hr, 24hr, 96hr, 7d and 14d and blood factors were measured using standard methods. Result showed that with the increase in pesticide concentration, a significant increase was observed in the concentrations of glucose, cortisol, RBC, Ht, Hb, MCV, MCH and MCHC at 12hr and 24 hr, and then the mentioned parameters decreased at the end of the experiment period. In addition, WBC, lymphocyte and eosinophil significantly increased at high concentrations of pesticide, and monocyte and basophil decreased. According to the results, Chlorpyrifos have shown the intensive effects on physiological and immunological characteristics of the carp. Additionally, blood factors, especially the amount of RBC and WBC, can be introduced as health bio-indicator of Grass carp and aquatic environment.

Presence of azinphos methyl and diazinon was reported in Gorganrod and Gharesou River. In present study the effect of sub-lethal concentration of these pesticide on some blood biochemical and hematological parameters of Caspian Roach (rutilus rutilus) was investigate. The result of this study showed that, both of pesticide caused increase of ALT, AST and ALP in treated groups. Also, comparison between tow pesticides showed that diazinon has more effect on these enzymes activity. With regards the results, after exposure to azinphos methyl and diazinon, RBC and Hb decreased but in contrast, WBC increase. Also the results showed that after treatment with both pesticides, blood indices such as MCV, MCH AND MCHC significantly decreased in compare to control group but haven’t different between azinphos methyl and diazinon. Due to results of this study it can be said that sub lethal concentration of azinphos methyl and diazinon that are approximately close to their concentraions in environment, lead to adverse effects on a broad range of hematological parameters.

In the present study, we investigated the effects of short –term exposure (96 h) and sub-lethal concentrations of diazinon on energetic (glucose, lactate) and osmotic parameters (chloride cells number, cortisol, total protein, blood plasma ions) of Persian sturgeon juveniles (Acipenser persicus) during salinity adaptation to seawater. 500 fish were distributed in twelve 100 L tanks at density of 40 fish per tank. The experimental treatments were: (1) 0.3 ppm (%10 LC50 96 h) diazinon, (2) 0.9 ppm (%30 LC50 96 h) diazinon (3) 1.5 ppm (%50 LC50 96 h) diazinon. Also, one diazinon-free group was considered as control. The experiment was conducted in two stages including: 96 h exposure in freshwater (FW) and 24 h exposure in brackish water (BW: 12 ppt salinity). After each stage, blood and gill tissue samples were taken. The results that diazinin can affect energetic and blood osmotic parameters of Persian sturgeon juveniles before and during the salinity adaptation period, especially in high concentrations (including 0.9 and 1.5 ppm). These effects includes: (a) 96 h exposure in FW: increase in cortisol, glucose, lactate and number of chloride cells (only in 0.3 ppm group) and decrease of ions. (b) 24 h exposure in BW: increase in cortisol, glucose and ions. In conclusion, our study showed that sub-lethal concentrations of diazinon (especially 0.9 and 1.5 ppm) reduce the potential of osmoregulation of the Persian sturgeon juveniles during salinity adaptation to seawater. These effects were: decreases in number of chloride cells, increases in stress indices (cortisol and glucose), changes in permeability of gills tissue and causing anaerobic condition which can affect the success of rebuilding the reserves of this precious species.

Aquatic environments are often contaminated by various industrial, agricultural and domestic sewage, while different pesticides have markedly different effects on aquatic life. Scenedesmus spp. are often used as an indicator to show changes in physico-chemical and environmental conditions of the aquatic ecosystems. This study aimed to investigate the effects of different concentrations of pesticides, fungicides tilt(propiconazole) and benomyl on the population of green algae (Scenedesmus quadricauda) and to determine 96 hour EC50 for it. The study was conducted in a completely randomized design at 96 hours with 4 treatment (four levels of pesticide and control)and three replications in medium BBM (Bold Basal Medium) in accordance with O.E.C.D as standard method. The highest mortality rate occurred at 2.5 mg/L and is 28.40 µg/L of fungicides Benomyl and tilt, respectively. Also, 96 hours EC50 determined 0.834 mg/L for benomyl and 6.612 µg/L for tilt. Statistical analysis showed the significant differences in daily growth rate between some concentrations of studied toxin, as the cell density decreased with increasing toxin consebtration. Overall results indicated that fungicide benomyl with Degree of toxicity very high toxicity(dangerous) existing in the water bodies has an influencing effect on cell destruction of green algae (S. quadricauda). Also the results suggested using such species (S. quadricauda) as an indicator for biomonitoring of aquatic ecosystems because of its rapid response to contaminants.

Chlorpyrifos is one of the organophosphate pesticides that are commonly used to control insects in domestic activities and many agricultural farms that are located in close to water sources. Hence, the present study, investigate the lethal toxicity of this pesticide. In this study, fish were treated in groups of 21 with different concentrations of chlorpyrifos (Aria brand with active ingredient 40/8% EC) for 96 hours and mortality was recorded. Toxicity tests were determined by Probit statistical analysis in software SPSS, version 16. At the end of 24 hours, mortality was 100% in fish with a concentration of 200 mg/l chlorpyrifos. LC50-96h this pesticide was calculated 83.2 mg/l. However, mortality was observed 100% for diazinon and deltametrin at the end of 96 hours. LC50-96h diazinon and deltametrin were less than chlorpyrifos that shows diazinon and deltametrin have more toxicity in comparing with chlorpyrifos. Finally, Carassius auratus is a suitable model of Cyprinidae that constitute a big group of rearing fish and because of chlorpyrifos lower toxicity, seems to using of this pesticide stead other common pesticide had been low danger in agricultural fields.