Recognizing of Ichthyophon and investigation of feeding and effects of water temperature, salinity and electrical conductivity on the population dynamic of Barbus grypus in the Dalaki and Helle river

This study was carried out for recognized ichthyophon and investigation of feeding and effects of water temperature, salinity and electrical conductivity on the population dynamic of Barbus grypus in the Dalaki and Helle river. In the study period, 2949 Barbus grypus was cached. The most of total length frequency was 200 to 300 mm and 2 to 3 years old. The oldest fish was8 years old with 756 mm total length. Fecundity was 950 upto 57400 oocyt per fish. Station no. 6 and 7 showed more temperature, fecundity and GSI than other stations. Females adulated before then males. Multiple stepwise regression of fecundity and RE (reproduction effort) showed significant correlation. Fishes of the upper parts of stream was more L than down stream stations. Condition factor of males was more than female, and for down stream stations was better than the other stations. Barbus grypus is omnivorous. Ichthyophon of Dalaki river include 4 family and 9 species that Capoeta capoeta intermadia was more than others species, but in the Helle river was 5 family and 9 species, that Liza abu zarudni was more than others

A histo-morphological characteristics of gonads in Mudskipper, Periophthalmus waltoni Koumans, 1941 from Helleh estuary, Southwestern Iran

In this study, the morphological and histological studies of male and female gonads in mudskipper, Periophthalmus waltoni Koumans, 1941 from Helleh estuary (Bushehr Province, southwestern Iran) were performed to determine its gonadal development stages and histo-morphological characteristics. Sampling was done from April 2010 to March 2011 and a total of 81 individuals were collected by hand net. The gonads of specimens were removed, their sexes determined and then fixed in 10% formalin solution after checking their morphology and measuring their weights, lengths and widths. Six stages of gonadal development in females and four stages in males were determined based on macroscopic and microscopic observations and reproductive indices. In female, increasing of the ovary size is occurred because of the accumulation of yolk materials in oocytes, and in the last stages, little folding in ovary was observed. Formation of zona radiata and yolk granules in the third stage, and increasing thickness of this layer and yolk granules were observed from stage three to stage six. In male, gradual developments of the sperm cells were observed from stage one onward

Data onmetallevelsintheinletandoutlet wastewatertreatmentplantofhospitals in Bushehrprovince,Iran

In thispaper,wemeasuredthelevelsofmetalsincludingPb,Cr, Cd, Ni,Hg,Fe,andCuintheinletandoutletwastewaterofhos- pitals. ThesamplesweretakenfromwastewaterinBushehr's provincehospitals,Iran.Afterthecollectionofsamples,thecon- centration levelsofmetalsweredeterminedbyusinggraphite furnace absorptionspectrometer(AAS)method(Varian,SpectrAA 240, Australia).Statisticalanalysisofthedatawascarriedoutusing Special PackageforSocialSciences(SPSS16)

Incidence of Lernaea (Crustacea: Copepoda) parasitic in the Mashkid River Basin, Southeast of Iran

In the present investigation, Lernaea parasite was reported in the examined fish species, collected from the Mashkid River basin, Southeast of Iran in 2012 and 2013. Lernaea parasites were isolated from the external surface of eye, fins, operculum and body of the Bangana dero, Cyprinion microphthalmus, Gonorhynchus diplocheilus (Cyprinidae), Aphanius dispar (Cyprinodontidae), Channa gachua (Channidae) in different water bodies. The highest infection was found in native fish, B. dero with nine parasites in single specimen. The exotic fishes were not infected

A new approach for designing a hypolimnetic oxygenation system to improve the water quality in tropical reservoirs

Background: One of the most important problems of dams is thermal layering which directly affects the water quality. This study was performed to propose a solution to increase the water quality of the Esteghlal Dam reservoir in Minab, Hormozgan. Methods: The water quality of Esteghlal Dam was evaluated from 2016 to 2018. During this period, 18 samples were collected from three different points of the dam. The parameters of water temperature, electrical conductivity, total dissolved solids, total suspended solids, dissolved oxygen (DO), pH, nitrate, phosphate, turbidity, biochemical oxygen demand, chemical oxygen demand, total hardness, anions and cations, total phosphorus, physicochemical, and microbial parameters were measured according to the method recommended in the standard method book. The obtained data were used as the input for the model of reservoir water quality (CE-QUAL-W2) to simulate reservoir water quality and predict the thermocline cycle. Finally, by plotting hypolimnion oxygen content against time and finding the slope of regression line using the data, the hypolimnetic oxygen demand (HOD) was obtained. Results: The findings showed that the anaerobic condition occurred in the hypolimnion layer during summer. Furthermore, it was revealed that the HOD of Esteghlal Dam is about 6 g of oxygen per square meter per day in the current situation. Conclusion: Considering the dam’s conditions and its anaerobic problems, a hypolimnetic oxygenation system is proposed as a structural solution for this reservoir. Then, conductivity-temperature-depth (CTD) profiles and monitoring data were used for the oxygen supply model of plume. The reservoir was predicted after calculating the amount of oxygen required using the equations governing linear oxygen supply systems and the plume model. Keywords: Anaerobiosis, Oxygen consumption, Water quality, Phosphorus, Ammoni

A histo-morphological characteristics of gonads in Mudskipper, Periophthalmus waltoni Koumans, 1941 from Helleh estuary, Southwestern Iran

In this study, the morphological and histological studies of male and female gonads in mudskipper, Periophthalmus waltoni Koumans, 1941 from Helleh estuary (Bushehr Province, southwestern Iran) were performed to determine its gonadal development stages and histo-morphological characteristics. Sampling was done from April 2010 to March 2011 and a total of 81 individuals were collected by hand net. The gonads of specimens were removed, their sexes determined and then fixed in 10% formalin solution after checking their morphology and measuring their weights, lengths and widths. Six stages of gonadal development in females and four stages in males were determined based on macroscopic and microscopic observations and reproductive indices. In female, increasing of the ovary size is occurred because of the accumulation of yolk materials in oocytes, and in the last stages, little folding in ovary was observed. Formation of zona radiata and yolk granules in the third stage, and increasing thickness of this layer and yolk granules were observed from stage three to stage six. In male, gradual developments of the sperm cells were observed from stage one onward