Qualitative assessment of Caspian kutum (Rutilus frisii kutum Kamensky 1901) stocks in Iranian waters of the Caspian Sea (1991-2011)

The main objective of the present study was qualitative assessment of Caspian kutum (Rutilus frisii kutum Kamensky 1901) stocks by using indicators of overfishing, condition factor and relative weight in Iranian waters of the Caspian Sea during a long period (1991- 2011). Three fisheries indicators in catch were: 1) percentage of mature fish, with 100% as target; 2) percent of specimens with optimum length, with 100% as target; and 3) percentage of mega-spawners, with 0% as target, and if no upper size limit exists, 30-40% as representative of reasonable stock structure. Over this period, the condition factor and relative weight had a decreasing trend. The range of length with optimum yield was between 40 and 48 cm. The mega-spawner measured as fish a size larger than 48 cm. According to these three indicators, the percentage of mature (fork length>40cm), optimum size and mega-spawners were 62.0, 40.9 and 12.5% in 1991-92 which decreased less than 50, 38.2 and 8%, in the years 1992-2011, respectively. The length structure is a matter of concern. Therefore, for reservation and rebuilt of kutum in the Caspian Sea, the target was to let all (100%) fish spawn at least once, using bigger mesh size in cod end (e.g. 35mm, during whole fishing season). The aim was also to implement a fishing strategy that result no (0%) mega-spawners being caught, and the main catch focus on optimum length

Cauda equina entrapment in a pseudomeningocele after lumbar Schwannoma extirpation

Incidental or intentional durotomy causing cerebrospinal fluid (CSF) leakage, leading to the formation of a pseudomeningocele is a known complication in spinal surgery. Herniation of nerve roots into such a pseudomeningocele is very rare, but can occur up to years after initial durotomy and has been described to cause permanent neurologic deficit. However, cauda equina fiber herniation and entrapment into a pseudomeningocele has not been reported before. Here, we present a case of symptomatic transdural cauda equina herniation and incarceration into a pseudomeningocele, 3 months after extirpation of a lumbar Schwannoma. A 59-year-old man, who previously underwent intradural Schwannoma extirpation presented 3 months after surgery with back pain, sciatica and loss of bladder filling sensation caused by cauda equina fiber entrapment into a defect in the wall of a pseudomeningocele, diagnosed with magnetic resonance imaging. On re-operation, the pseudomeningocele was resected and the herniated and entrapped cauda fibers were released and replaced intradurally. The dura defect was closed and the patient recovered completely. In conclusion, CSF leakage can cause neurological deficit up to years after durotomy by transdural nerve root herniation and subsequent entrapment. Clinicians should be aware of the possibility of this potentially devastating complication. The present case also underlines the importance of meticulous dura closure in spinal surgery

Study on the growth status of mullets with viral nervous necrosis disease in the southern Caspian Sea

Mullet and mullet products have considerable economic importance at a regional level, especially around the Caspian Sea. The leaping mullet constitutes an important part of their production. This study is the first detailed work on the age and growth of the leaping mullet (Liza saliens) from September 2012 to March 2013 in the Southern coast of the Caspian Sea. Age and growth determinations were based upon the scale samples taken from 102 fish. Marginal increment analysis was used to validate age determination. The back-calculated lengths stage estimated from the scale showed no differences between in this study. The maximum age of leaping mullet in the Southern coast of the Caspian Sea was 5 years for males and 6 years for females. The von Bertalanffy growth functions were Lt=30.415(1-e-0.275(t+0.645)) for males and Lt=34.832(1-e 0.211(t+1.009)) for females. A large spread and length overlap characterized the age groups. The estimated Length Weight relationships were common for the two sexes (W=0.079L3 ). The slope (b) values of the length-weight relationship showed that weight of leaping grey mullet in Mazandaran increased associated with length in isometric. The mean condition factor for males, females and all specimens were determined as 0.908, 0.900 and 0.897, respectively. According to sex groups, the mean condition factor of males was slightlyhigher than that of females. The total length for leaping grey mullet was determined as 23.3 cm

Determination of sediment nutrients in the cage fish culture area (before breeding) of the southern Caspian Sea (Mazandaran coast-Kelarabad)

This study was conducted to determine phosphorous and nitrogen species at the surface sediment in the southern Caspian Sea (Mazandaran Coast, Kelarabad). Surface sediments samples were collected at three stations from autumn of 2011 to winter of 2012. All samples were prepared by digesting and extracting processes and then phosphorous and nitrogen species concentrations determined using spectroscopy instrument. Results of this study showed that annual mean of Loosely-P, Fe-P, Al-P, Bioava.-P, Ca-P, TIP, Rese.-P and TP was obtained as 5.06±0.33, 55.11±2.52, 42.38±3.74, 102.52±5.68, 172.91±7.12, 275±9.12, 333.30±28.52 and 608±52 µg/g.dw, respectively. The results also showed that inorganic phophorous was less than organic phophorous during different seasons, however, mean percentage of residue-P containing organic compounds and non-degradable compounds was more than 50 percent. Percentage of Ca-P was higher than 60, whereas Bioava.-P was less than 40 percent. In addition, Fe-P and Loosely-P attained the maximum and minimum values, respectively, among the bioavailable phophorous. The order of different forms of phosphorous were recorded as Org-P>Ca-P>FeP>Al-P>Loosely-P. Annual mean of NH4/N, NO2/N, NO3/N, TIN, TON and TN were observed as 4.23±0.50, 0.06±0.01, 0.74±0.12, 5.02±0.53, 2.48±0.63 and 7.53±0.51 µg/g.dw, respectively. Annual percentage of TIN was two folds than TON and concentration of NH4/N was also four times than NO3/N. As a conclusion, the results revealed that main causes of Bioava.-P adsorption and desorption were temperature, Eh and pH. Also, the form of NH4+/N was of a high percentage because of anaerobic condition in the sediments. According to the high ratios of nitrogen/phosphorous of sediments to nitrogen and phosphorous of bottom water, it finds that released of those from the sediments to water will be happened with high rates. Therefore, it is expected that the establishment of fish farming cages should be carried out with more precautionary approaches which not leads to increased algae bloom

Preparation instructions micro-algae cultivate and concentrate it for use in silver carp feed and training necessary

According to the importance of micro-algae in aquatic feed such as fish in this study have been investigated Preparation of useful algae powder or concentrate for breeding silver carp , their impact on the growth of silver carp , rate per unit area and estimate n economic Development. Different algal species were isolated from hydrothermal fish farms, then were purified and mass culture . The next step microalgae were dried and powdered by spray dryer and were examined the fish feeding on them. During this study, 6 species of chlorophyt( Scenedesmus obliquus, Scenedesmus acuminatus, Chlorella vulgaris, Pediastrum boryanum, Pandorina morum, Ankistrodesmus falcatus) ,3 species of cyanophyta ( Anabaena flosaquae, Oscillatoria agardhi and Spirulina platensis) and 1 species of Bacillariophta ( Cyclotella meneghiniana were isolated from.Green algae and Blue -green algae were cultured in Zaindr medium, diatoms were cultured in Zaindr medium but with water of Anzali logoon and also in F2 medium with artificial sea water and spirulina was cultured in Zarouk medium. Microalgae were cultures then concentrated.Then the impact was examined on fish silver carp 2 to 3 grams. The results showed that Cyclotella has a greater role in the growth of silver carp and Anabaena floes aquae and Spirulina platensis tend to growth less than cyclotella. Scenedesmus obliquus and Scenedesmus acuminatus were respectively next algae that showed the greatest impact on fish growth. Scenedesmus obliquus feed rate was greater than any other algae for Daphnia

Study and relocation of corals in developing area of Shahid Beheshty port, Chabahar

The conservation of coral colonies is very vital for marine organisms and human. In Chabahar Bay, the coral reefs are in danger of destruction due to the development program of Shahid Beheshti Port. In this project, over 30,000 hard corals were transported to coast of Hotel Lipar an area at a distance of 3.5-4 kms far from Shahid Beheshti Port. Also, the new techniques were used for coral reattachment and transportation. The operation has done within expert divers and consultancy of Prof. Dr. Maikle Risk. Four methods performance as pailots. Since the corals are very sensitive to turbidity and suspended sediments from land reclamation and dredging projects, therefore appropriate measures should be conducted for conservation and recovery of them.37 patches in size 5×10 meters has built with concerete. Diffent sizes of corals were separated by mechanical tools and transported to new sites and reattachment on artificial sea bottom.Three monthes after the last reattachments monitored showed that %96.93 of corals were in good health. This success was the important achievement because of innovating coral carrier and mass coral relocation. At present, the coral relocation is suggested as a good method for recovery of coral reefs after a disturbance in condition of their native habitats

The effects of slurry on larviculture of Rutilus frisii kutum and chienes carp yield and determination of efficient concentration for increasing of production

Rutilus frisii kutum is one of the important fish of Caspian Sea which has significant economical role in the region .The objective of this project is a comparative study on traditional culture of fishes versus slurry. This survey were conducted on nine pound of 1.7 hec triplicate with their treatment with stocking densities of 1.7 million fish larva at Dr yousefpoor center (Affiliated of Shahid Beheshti culture and propagation) at Siakal village , 32 km far from Rasht city in North of Iran, the first treatment considered as control which practice traditionally (using concentrated food plus grinded kilka fish) .In the second treatment for 13 days the pound supplied only by slurry then followed by concentrated fish food only .The tired treatment started with slurry for 13 days and followed by slurry plus concentrated food. The physical and chemical parameters of water, plankton, biometry of fish, growth indices such as daily weight growth (DWG), daily length growth (DLG) as well as specific ratio (SGR) were monitored weekly. The result indicate that net fish production was 1.7 to 2 times higher in slurry than traditional treatment also the survival rate were 1.7 times higher in slurry treatment . The treatment of slurry follow by addition of concentrated food plus slurry showed higher yield camper to others. Slurry with several active substances is more effective and can promote the growth of zooplanktons which is the food of larval stage of rutilus frisi kutum. In second phase of this project the effect of slurry was surveyed on Chinese carp. This experiment was conducted in triplicate with two treatment (one treatment is control which use cow manure plus chemical fertilizer and second treatment was conducted with slurry) and stocked with 2375 N/hec (Silver carp 60%, Big head 15%, common carp 17% and grass carp 8%) at June. In this survey common carp and grass carp were feed with concentrate food and fresh grasses respectively. Chemical factors were measured once for each two week and density of plankton was determined when it was necessarily. Nutritional content of phosphorous, nitrogen, calcium, potassium and magnesium after anaerobic fermentation as well as protein and lipid content with 1.4and 1.9 times respectively were higher in slurry treatment than control. The results showed that survival rate and yield were higher in slurry than control. The increasing percent of yield were 13.5, 2.6, 18.4 and 85.3 in Silver carp, Big head, common carp and grass carp respectively. The survival rate of grass carp was twice higher in slurry treatment than control. Zooplankton abundant in slurry pounds was more but blue- green algae density was less than control. Protein and lipid analysis reviled no significant difference between control and slurry. In general the result indicate that the slurry with higher nutritional content is more effective on the survival and growth rate of fishes and also is more efficient in proliferation of plankton in particular zooplankton

Stock enhancement and estimation of growth rate of green tiger prawn (Penaeus semisulcatus) and banana shrimp (Fenneropenaeus merguiensis) released in the Persian Gulf

Present study was conducted in the Persian Gulf (Iranian waters) from 2009 to 2012. The main objective of the research was economical evalution of the stock enhancement of banana prawn (Fenneropenaeus merguiensis) and green tiger shrimp (Penaeus semisulcatus) in the studied area. Also tagging effects on the growth and mortality of tagged shrimp were studied. In banana prawn, broodstock shrimps were hatched in June. In July 2010 and 2011some of the juvenile of this species were marked by red fluorescent liquid injection and released were made at night in the estuaries of Tiab, Kolahi and Koolgan in the Hormozgan province. 84000 juveniles of banana prawn in 2010 and about 50000 in 2011 were released in this area. In Bushehr province waters, adults shrimp were reared and when juveniles reached to optimum size, some of them were tagged by red and blue coloures and were released in the coastal waters of Bandargah and Delvar. Tagging and releasing program of green tiger prawn was performed in 2010 and 2012. A total number of 8000 prawn in 2010 and about 30000 juveniles prawn in 2010 were released. Activities for recaptured shrimps were informed by posters describing the tagging program that were distributed to local peoples, as well as local magazines, and a tagging program awareness film was broadcast on national television three times prior to the shrimp fishing season and during catch season. To encourage people to report recaptures a reward of two handered thousent riales was paid for the return of each marked shrimp accompanied by information. Economical evaluation of banana prawn was performed based on releasing and recaptured program in 2011. As it mentioned in this year 50000 of juvenile shrimp were tagged and released. At the same time 4700000 of unmarked shrimp were released in this area. In the shrimp season 11 (./022%) of tagged shrimp were recaptured. Movements of tagged shrimp were northwesterly to released area. Weight average of tagged prawns was 1.2 gram. Mean weight of the recaptured prawns was 22.06±4.9 gram. Body weight Growth of the recaptured prawns was between 16-26 grams with the growth speed of 0.88-1.41 per week. The number of recaptured prawn to the released prawn was 0.022 percent. Based on the released prawns (4700000) to the recaptured percent (./022%), about 103400 of released shrimp with mean weight of 2.5 tones were observed in the Hormozgan shrimp catch. The average price of shrimp in the studied year in the local market was 85000 Rials per kilogram. These results showed that the ratio of profit is 210 milion riales. In the taggiing program of green tiger prawn in the Bushehr waters only one recaptured shrimp was observed in the catch season (2012). Total weigth and total length of this prawn was 99 gram and 22 centimeter respectively .given the small percentage of the recaptured, economical analyses was not performed on this species. The effects of tagging on the growth and mortality of green tiger prawn were studied. The present study was carried out in the shrimp research station in Bandargah and Abzistan shrimp Hatchery Company in Delvar during 2010 and 2012. The accuracy of the study was more rialable in 2012. In this year growth and mortality of juveniles that was marked by red and blue coloures, were studied in both area Bandargah and Delvar. In Bandargah, three tanks of 300 l each with 30 specimens were used for untagged shrimp as a control group, and tagged with injected liquid fluorescent during 98 days. Length and weigh of 10 specimens were measured evenly in different times. ANOVA results (α = 0.1 and α = 0.5) showed no significant differences between length growth of tagged shrimp and control group. The mortality of two groups was evaluated by numbering of remained shrimps and the average of survival was 52 percent in the tagged and 44.5 percent in tagged shrimps. In the Delvar station, Abzistan Company, the specimens were kept in the 9 tanks each 300 l that included of 30 untagged shrimps, 30 blue tagged shrimps and 30 red florescent tagged shrimp. The growth and mortality of this station were evaluated during 110 days. The growth rate of the specimens were measured and recorded evenly. The results of ANOVA (α = 0.1 and α = 0.5) showed no difference significantly in the weight growth of tagged and control groups. The mortality rates among the control group, red tagged and blue tagged were 63 percent, 59 percent and 40 percent. The mortality of the groups was differences in the two stations and it seems the management and environmental conditions were more affected on the mortalities. The results of the study show that the ratio of profit to the coast is 0.46 that is covering half of the coasts, so that the expenditures are two times more than profit. This result is the minimum of economical value of stock enhancement of shrimp. The results of study showed that the injected tags into the body tissue of shrimp has no affected on the growth rate and mortality