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Showing 26 results for Alizadeh
H. Hosseinzadeh , Sh. Masaeli , H. Negarestan , M. Alizadeh ,
Volume 20, Issue 3 (10-2011)
Abstract
In this research, controlled changes of rainbow trout muscular composition cultured in brackish water (14.1ppt) and freshwater (4.3ppt) was compared. Some 180 juvenile rainbow trout with a weight of 47.2±0.1g each were released in 6 polyethylene tanks with a capacity of 1.5m³. During the experiment, water temperature was kept constant. Feeding fish was conducted using common Faradaneh food and considering water temperature and fish biomass. After 126 days, fishes attained around 320±20g of weight, were sampled and taken to laboratory and the amount of protein, fat, ash, minerals and moisture in their muscle tissue were measured. Results showed amount of fat and dry matter in brackish water cultured fishes is less than those cultured in freshwater. The average percentage of protein and minerals in brackish freshwater cultured fishes were significantly different and the average percentage of moisture in brackish water cultured fish was higher than those of the freshwater fish.
S. Shirvan , B. Falahatkar , H. Noveirian , A. Abasalizadeh,
Volume 22, Issue 3 (10-2013)
Abstract
The present study was designed and performed to investigate the eefect of long-term some feeding
strategies (starvation, restricted feeding at rate of 1% biomass per tank and satiate feeding as control)
on growth performance and body composition of juvenile Siberian sturgeon (Acipenser baerii Brandt
1869) for 8 weeks. In this regard, 270 juveniles Siberian sturgeon (average weight 54 ± 6/27 g and
density 1.5 g/l) were distributed in three treatments (with three replicates) in 9 fiberglass tanks (1050
l). For all fish in each tank, body weight and total length were individually recorded at a biweekly
interval. At the termination of the experiment period, five fish per replicate were caught randomly for
proximate composition. Results showed that growth performance of Siberian sturgeon was affected
significantly by starvation and restricted feeding periods. Moisture and lipid contents were differed
significantly in all treatments which the highest moisture and lipid contents were observed in starved
and control fish, respectively. Protein content in starved fish was significantly lower than other groups,
whereas ash contents were not significantly different among the treatments. In general, weight loss and
other growth factors of juveniles siberian sturgeon during the food shortage were refered to mobilizing
the body lipid reservesand then body protein sources and replacing with water. In fact, juvenile
Siberian sturgeon can conserve body protein stores better than lipids during the food shortage period
S. Dehghan , G. Zarshenash, S. Sabzalizadeh, M. Nilsaz , A. Motallebi , Y. Mayahi ,
Volume 24, Issue 1 (4-2015)
Abstract
The monitoring of the harmful Alga blooms (Red tide) in the the Khuzestan coastal waters Provinces was carried out monthly at 5 stations during 2010 to 2011. The results revealed that, Coclodinum polykrikoides blooms was not occurred during investigation times , Phytoplankton composition species were included of 45 species of diatoms (%91), 9 species of Dinoflgellates (7. 52%) and Cyanophytes with one species (1.88%).. Furthermore significant different values of nutrients were recorded. Different values of NH4 were measured for different months. In total, the measured ratio of N: P in all months were lower than Redfield Ratio (16:1) in which subsequently the environmental condition was not suitable for bloom of C. polykrikoides.
M.h. Khanjani , M.m. Sajjadi , M. Alizadeh , I. Sourinejad,
Volume 24, Issue 2 (7-2015)
Abstract
In this study, effect of different feeding levels on water quality, growth performance and survival of western white shrimp Litopenaeus vannamei post larvae were studied in biofloc rearing system. Shrimp postlarvae of PL10 with mean weight of 3±0.7 mg and mean length of 4.4± 0.93 mm were fed for three weeks in fiberglass containers with 200 liters volume of water and density of 10 post larvae per liter in four tretments including one control with water exchange and three biofloc treatments at different feeding levels of 25, 20 and 15% of body weight. According to the results, in the values of water quality parameters including temperature, salinity, dissolved oxygen and pH, no significant differences were observed among the groups (P>0.05). The highest increase in body weight (58.42 mg), growth rate (2.78 mg per day), specific growth rate (15.09 %/day), biomass (84020 mg) and survival rate (71.9%) were obtained in biofloc treatment at 25% feeding level .The highest feed conversion ratio (2.05) and the lowest feed efficiency (48.62%) were obtained in water exchange treatment without floc, showing significant difference compared to the other treatments (P <0.05). The results from this study reveals that by using biofloc rearing technology can decrease the amount of water exchange and feed utilization compared to body weight in culture of western white shrimp post larvae. Moreover, the presence of biofloc improves growth performance and production of L. vannamei post larvae in biofloc rearing system.
Mohammad Hossein Khanjani, Morteza Alizadeh, Mir Masoud Sajjadi, Iman Sourinejad,
Volume 24, Issue 3 (10-2015)
Abstract
Eeffect of different dietary carbon sources on water quality, growth performance and survival of
western white shrimp Litopenaeus vannamei post larvae was investigated in zero-water exchange
system. Shrimp postlarvae with mean weight of 98.47±8.60 mg and mean length of 22.39± 1.70
mm were fed for 32 days in fiberglass containers with 130 liters volume of water and density of 1
individual per liter in five treatments including one control with water exchange and four biofloc
treatments with adding different carbon sources including molass, starch, wheat flour and mixture
of them at equal weight ratios with 15% to 9% of body weight. In the values of water quality
parameters including temperature, salinity, dissolved oxygen and pH, no significant differences
were observed among the biofloc treatments (P>0.05). Maximum pH (8.27 ± 0.09) and maximum
dissolved oxygen (6.37 ± 0.56 mg/lit) was in water exchange treatment. Maximum and
minimum level of ammonia was 0.43± 0.34 and 0.09± 0.07 mg/lit in water exchange treatment
without floc and biofloc treatment with adding starch of carbon sources, respectively and showed
significant difference between treatments (P <0.05). The highest increase in body weight
(1640.43± 231.28 mg), growth rate (51.26± 7.23 mg per day), specific growth rate (8.97± 0.42
%/day) and biomass (190.29± 26.83mg) was observed in biofloc treatment with adding molass
and the highest survival rate (90± 0.77%) was obtained in biofloc treatment with adding mixture
of carbon sources. The highest feed conversion ratio (1.52±0.23) and the lowest feed efficiency
(66.81±7.95) were obtained in water exchange treatment without floc, showing significant
difference compared to the other treatments (P <0.05). The results showed that using biofloc
technology with zero- water exchange system and adding carbonaceous organic matter could help
to recycle waste and improve the water quality. Moreover, the presence of biofloc improved
growth performance, feed utilization and production of western white shrimp in zero water
ecxhange rearing system.
H.r. Alizadeh Sabet , M.r. Kalbassi , M. Pourkazemi , M. Sadeghizadeh,
Volume 25, Issue 1 (4-2016)
Abstract
Out of considerable environmental factors, temperature and its possible effects on life stages of Caspian trout investigated by natural incubation (8 ͦC) condition simulation comparing with cold (4 ͦC) and warm (12 ͦC) constant incubation temperatures in 3 well equipped incubators by water recycling systems. Green eggs triple treatments of wild and F1 cultured brooders were incubated. Incubation implemented in dark by using REDD water and DO–pH –temperature digital monitoring ended to yolk sac absorption and entering larval stage. Numbers and diameters of white fiber muscles measured and significant differences considered between three thermal treatments (P<0.05) in both wild and cultured stocks. The numbers of white fiber muscles in warm treatment by highest means (72.54) and lowest diameter (8.46 micrometer) compared with Cold treatment white fiber muscles diameter (20.59 micrometer) and numbers (50.72) which were the highest diameter and lowest numbers means between treatments. Hatching success stated considerable mortality for cold treatments and 8°C incubator improved the best temperature in wild treatment. Incubation temperature induced significant effect on white fiber muscles stated considerable index for flesh precursor muscles condition which is subject of natural stocks rehabilitation and domestication projects considerations.
M. Alizadeh , R. Razieh Ansari , Sh. Dadgar , M. Hafezieh ,
Volume 25, Issue 1 (4-2016)
Abstract
This research was done in a trout farm in Kohkiloyeh and Boyer- Ahmad province. The main object of this study was comparing of two sources of astaxanthin (synthetic or algae) in feed on astaxanthin content of egg in rainbow trout. It was considered seven groups consisting six treatments (T1-T6) in two different astaxanthin sources and a control (C) (without astaxanthin). So, algal astaxanthin (haematococcus pluvialis) in the three levels of 2.67, 3.55 and 8gr/kg food (T1,T2, T3); and synthetic astaxanthin in three levels of 40, 80 and 120mg/kg food in diet (T4, T5, T6) examined on 140 trout broods (3-4 years) for 4 months, before the spawning season. Astaxanthin content of obtained eggs from all treatments in spawning season was measured by HPLC apparatus. The highest and the lowest amount of egg astaxanthin were observed in T3 and C respectively. In each astaxanthin group, a significant difference was obtained between averages in treatments (P <0.05), as T3 was the highest between them. No significant difference was observed between synthetic astaxanthin treatments (T4, T5 and T6) and T1 (the lowest level of algal astaxanthin). Treatments T2 and T6 also had the same function in term of saving astaxanthin in eggs. It also concluded that natural astaxanthin (Haematococcus pluvialis) for the reason that contains supplementary nutritious, is extraordinary preferable than synthetic astaxanthin to improve astaxanthing content of egg in rainbow trout.
M. Hashemimofrad , M. Sattari, M. Khoshkholgh , A. Shenavar Masuoleh, A. Abasalizadeh ,
Volume 25, Issue 2 (7-2016)
Abstract
M. Alizadeh, M.h. Khanjani, R. Ansari, A. Rafieipour,
Volume 25, Issue 4 (1-2017)
Abstract
In present research, effect of dietary astaxanthin levels in sources of synthetic and algal on vitamins A and E content of egg rainbow trout broodstock was investigated, totally for 120 days. It was considered seven groups consisting six treatments (T1-T6) in two different astaxanthin sources and control (C). According to experiment design, treatments were arranged as algal astaxanthin (Haematococcus pluvialis) in the three levels of 2.67, 3.55 and 8gr/kg food (T1, T2, T3); and synthetic astaxanthin in three levels of 40, 80 and 120mg/kg food (T4, T5, T6). Egg vitamins A and E content in obtained eggs from all treatments during spawning season was measured. The highest (280.88± 22.51 ng) and the lowest (147.82± 12.71ng) amount of vitamin A were observed in T2 and control group, respectively. The highest (19.71± 2.92µg) and the lowest (5.27± 0.51µg) amount of vitamin E were obtained in T3 and control group, respectively. By increasing level of astaxanthin in both sources of algal and synthetic, content of vitamin E in egg increased but the effect of algal source on these indices was more perfect. In general present study show that, feeding broodstock affected on quality content of egg, It also concluded that natural astaxanthin (Haematococcus pluvialis) for the reason that contains supplementary nutritious, is extraordinary preferable than synthetic astaxanthin to improve vitamins content of egg in rainbow trout.
M. Alizadeh Nozari, M. Shapoori,
Volume 26, Issue 4 (11-2017)
Abstract
This experiment was conducted to examine the effect of dietary alphamion probiotic on growth, hematological indices and body composition of Huso huso fingerlings. A basal diet supplemented with 0 (control), 0.5, 1, 1.5 and 2 percent probiotic to formulate five experimental diets. Each diet was randomly allocated to triplicate groups of fish with initial average weight of approximately 192±3.2 g. After 8 weeks of feeding trial, fish fed diets with probiotic showed the highest final weight and SGR, and lowest in fish fed the control diet (P < 0.05). The feed conversion ratio (FCR) was better when the fish were fed diet with 2 percent prebiotic. There were significant differences in cortisol and lysozyme in fish fed by dietary probiotic (P < 0.05). At the end of feeding trial, the fish fed 1% diet showed higher whole body protein. The fish fed 2% diet exhibited lower levels of lipid and ash. The results suggest that administration of dietary alphamion probiotic at 1-2 percent exerted positive effects on growth, hematological indices and body composition in Huso huso.
A. Shenavar Masouleh, M. Pourkazemi, M. Soltani, M. Yarmohammadi, M.a. Yazdani, M. Alizadeh, J. Jalilpour, S. Bazari Moghaddam, M. Masoumzadeh, S.h. Hosseinifar, P. Esmaeili, Y. Baniesmaeili,
Volume 27, Issue 5 (1-2019)
Abstract
Caspian Sea sturgeons, are the most valuable species due to the production of meat and caviar. Sturgeon cultures as like other fish rearing, the outbreak of all kinds of infectious diseases in the farms can be expected and in this regard, isolation, identification and consumption of the local probiotics can be very important in the health promotion and growth indices. For this purpose, sampling has been done from 38 fish, in addition to culturing and counting aerobic and facultative anaerobic bacteria (AFAB) on Triptic Soy Agar, and lactic acid bacteria (LAB) were also isolated and counted on MRS Agar. In Siberian sturgeon, the average number of LAB were 2.72±0.11 (Log CFU g-1) and the average of AFAB were 6.79±0.19 (Log CFU g-1). Through 16SrRNA gene sequencing, LAB including Weissella confusa, Lactococcus lactis, and L. garvieae were molecular identified in the Siberian sturgeon intestines. Complete laboratory and field studies for use of these bacteria as probiotics is required.
M. Tavol Koteri, H.r. Alizadeh Sabet,
Volume 27, Issue 6 (3-2019)
Abstract
Considering the importance of estuaries as sensitive ecological areas and temporary habitat of many aquatic animals and also importance of Chironomidae larvae in the food chain and fish feeding, density and distribution of the chironomid larval and their relationship with environmental factors in Cheshmeh Kileh estuary of Tonekabon (South Caspian Sea basin) were investigated. Bimonthly from November 2014 to September 2015, in three stations (S1 in the river environment, S2 in estuary environment and S3 in the marine environment) samples were collected using Van Veen grab (0.03 m2) and Surber (0.1 m2, 0.2 mm-mesh size) with three replicates. Environmental factors of water including temperature and salinity and sediment relevant factors such as grain size and total organic matter percentage (TOM) were measured. In the present study, three subfamilies were identified, including Chironominae (5 genera), Orthocladinae (4 genera) and Tanypodinae (1 genera). 10 genera were reported from the river and estuary of cheshmeh Kileh for the first time. Among identified genera, the highest and lowest average densities were related to Orthocladius (235 ind. m-2) and Eukiefferiella (45.5 ind. m-2), respectively. Results of monthly distribution showed that the highest and lowest densities of chironomid larval were in March (320±133 ind. m-2) and in September (33.3±11 ind. m-2) respectively which were significantly different, by Duncan's test (p<0.05). Among sampling stations, river station (S1) showed higher density (248.3±93.6 ind. m-2) than estuary station (S2) (90.5±29.6 ind. m-2) and marine station (S3) (0±0 ind. m-2) which were significantly different (p<0.05). A significant Pearson correlation (p<0.05) between the density of chironomid larvae and environmental factors of water and sediment was found.
I. Sarhadi, E. Alizadeh Doughikollaee, E. Ahmadifar, H. Adineh,
Volume 28, Issue 2 (7-2019)
Abstract
The present study was conducted to evaluate the effects of dietary Artemisia annua extract on the hematological and blood serum indexes of common carp ( Cyprinus carpio). Fish with average initial weight (90.32± 1.12) were fed diets supplemented with graded levels 0, 0.5, 1 and 1.5 % of extract (T1, T2, T3 and T4) for 60 days. At the end of this period, The results showed that growth rate increased significantly (P<0.05) in fish fed diet containing plant extract in T3 (143.70± 10.62 g) compared with the control (130.63± 5.99 g). Results indicated that RBC, Hb and MCHC were higher in fish fed diets containing A. annua compared with the control. WBC, PCV and MCH had no significant change (P>0.05) in experiment groups compared with the control. Serum biochemical parameters showed that glucose levels were significantly increased in extract fed treatments. There was no significant difference in albumin levels between experimental treatments. The results of liver enzymes showed that fish fed diets had no significant difference (P>0.05) in activity of alanine transaminase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) compared with control. The addition of A. annua extract in the diet of common carp compared to control can be an acceptable effect on fish health status, but does not affect the liver enzymes.
S. Behzadi, Gh. Akbarzadeh, M. Darvishi, A. Salarpouri, M.s. Mortazavi, M. Barani, E. Alizadeh,
Volume 28, Issue 2 (7-2019)
Abstract
Four components were used to identification the effective physical-chemical factors of water on the variations of dominant fish families. The total variation of the variables was concluded 94/17 % and 90/5%, related to the loaded components in artificial reefs of Bandar-E-Salakh and Bandar-E-Bostaneh respectively.Assessment of the loaded factors in each of the components were identified that nitrate, nitrite, phosphate and chlorophyll a factors with positive load and temperature and salinity with negative factor load as the most important factors affecting the demographic changes of some fish families. Temperature, pH, nitrate, nitrite and phosphate were diagnosed parameters for water quality in two areas based on PCA results. The results of this study showed that nutrients (nitrate, nitrite, phosphate and chlorophyll a) had great influence on structure of fish in artificial reefs, that together with the physical-chemical parameters of water to impact on the chain and food web of fish and fauna of these ecosystems, ultimately.
Kh. Minabi, I. Sourinejad, M. Alizadeh, E. Rajabzadeh,
Volume 28, Issue 6 (2-2020)
Abstract
Effects of using various ratios of C:N in biofloc system on growth performance, feeding indices and culture water quality of common carp with mean weight of 14.17±0.36 g were investigated during 90 days in experimental treatments including control (no extra carbon source) and four treatments with different C:N ratios of 11, 15, 19 and 23 each with 3 replicates. The increase in C:N ratio had a significant effect on growth and feeding indices of cultured common carp in treatments (p<0.05). The highest final weight and weight gain, the lowest FCR and the highest SGR were observed in C:N ratio of 19. No significant difference was observed in survival rate among different treatments indicating that the culture condition was suitable for common carp in this biofloc system. Hepatosomatic and visceral indices did not show significant differences between treatments with different C:N ratios (p> 0.05). Water quality indices including DO, pH, TDS, EC, TSS, FV, TAN, nirtite and nitrate showed significant differences in biofloc system with different C:N ratios (p<0.05). The mean values of FV and TSS in biofloc system increased with increasing C:N ratio. The variation pattern of the mean TAN and nitrite were the same as each other and reverse to the trend of TSS and FV showed a decreasing trend with increasing C:N ratio. These trends indicate the significant removal of nitrogenous compounds by bioflocs. In conclusion, using C:N ratio of 19 with molasses as carbon source in biofloc system could be recommended to improve water quality, growth and feeding performance of cultured common carp.
Niki Nadalizadeh Tabari, Saeid Meshkini, Amir Tukmechi,
Volume 29, Issue 3 (8-2020)
Abstract
Lactobacillus is the most common probiotic bacteria. The aim of this study was to isolate and evaluate the probiotic properties of rainbow trout (Oncorhynchus mykiss) intestinal Lactobacillus and to improve the digestive tract of this fish. After preparation of 75 rainbow trout, their intestinal contents were cultured in MRS broth medium and 56 Lactobacillus colonies were identified by biochemical tests. Lactobacillus strains were identified by biochemical tests and polymerase chain reaction (PCR), and their antibacterial activity, susceptibility to antibiotics, bile resistance and acidic conditions (pH=3) was evaluated. A total of six Lactobacillus strains Lactobacillus acidophilus, Lactobacillus reuteri, Lactobacillus animalis, Lactobacillus fermentum, Lactobacillus leishmania and Lactobacillus delbrueckii were identified. The antibacterial activity of Lactobacillus leishmania against Yersinia ruckeri was significantly (p˂0.05) higher than the antibiotic Enrofloxacin. (p˂0.05). All isolates were resistant to oxacillin and vancomycin antibiotics and were sensitive to tetracycline. Lactobacillus animalis, Lactobacillus acidophilus and Lactobacillus delbrueckii showed the highest resistance to bile (p˂0.05), respectively, and Lactobacillus acidophilus showed the highest resistance to acidic conditions. According to the results there are probiotic Lactobacillus in the rainbow trout digestive tract, and among them Lactobacillus acidophilus, Lactobacillus reuteri and Lactobacillus delbrueckii have better probiotic properties.
Ahmad Podineh, Ebrahim Alizadeh Doughikollaee, Mohsen Shahriari Moghadam, Ehsan Ahmadifar,
Volume 29, Issue 5 (12-2020)
Abstract
The use of absorbent pads in packaged products caused the quality maintains and increase of marketability. But the nutrients accumulation in the adsorbent pad provides a environment growth for the microorganisms that cause spoilage. Therefore, the use of antimicrobial compounds in the adsorbent pad is essential for controlling the microorganisms growth. The aim of this study was to investigate the effect of absorbent pad containing Zataria multiflora leaf essential oil on chemical and microbial properties of Hypophthalmichthys molitrix fillet during storage in refrigerator. 10 ml of Zataria multiflora leaf essential oil 1.5 % were added to pad and fish fillets in different treatments, then packed and stored in a refrigerator (4˚C). The chemical (pH, Peroxide value (PV), thiobarbituric acid (TBA) and total volatile base nitrogen (TVB-N)) and microbial parameters (total viable count (TVC) and psychrotrophic count (PTC)) were measured on days 0, 3, 6, 9, 12 and 15. A significant difference (P <0.05) was observed between the pH of the treatments containing the essential oil and the control in the last days of storage. The results showed that the PV, TBA and TVB-N values of treatments increased during storage. So that the least increase was observed in the fillet containing essential oil, pad containing essential oil and control respectively. The TVC and PTC count of treatments significantly increased during storage (P <0.05). But this increase was less in the fillets containing essential oil than the other treatments. According to the results of this study, it can be concluded that the absorbent pad containing Zataria multiflora leaf essential oil cause the quality preservation and shelflife increase of Hypophthalmichthys molitrix fillet during refrigerated storage.The use of absorbent pads in packaged products caused the quality maintains and increase of marketability. But the nutrients accumulation in the adsorbent pad provides a environment growth for the microorganisms that cause spoilage. Therefore, the use of antimicrobial compounds in the adsorbent pad is essential for controlling the microorganisms growth. The aim of this study was to investigate the effect of absorbent pad containing Zataria multiflora leaf essential oil on chemical and microbial properties of Hypophthalmichthys molitrix fillet during storage in refrigerator. 10 ml of Zataria multiflora leaf essential oil 1.5 % were added to pad and fish fillets in different treatments, then packed and stored in a refrigerator (4˚C). The chemical (pH, Peroxide value (PV), thiobarbituric acid (TBA) and total volatile base nitrogen (TVB-N)) and microbial parameters (total viable count (TVC) and psychrotrophic count (PTC)) were measured on days 0, 3, 6, 9, 12 and 15. A significant difference (P <0.05) was observed between the pH of the treatments containing the essential oil and the control in the last days of storage. The results showed that the PV, TBA and TVB-N values of treatments increased during storage. So that the least increase was observed in the fillet containing essential oil, pad containing essential oil and control respectively. The TVC and PTC count of treatments significantly increased during storage (P <0.05). But this increase was less in the fillets containing essential oil than the other treatments. According to the results of this study, it can be concluded that the absorbent pad containing Zataria multiflora leaf essential oil cause the quality preservation and shelflife increase of Hypophthalmichthys molitrix fillet during refrigerated storage.
Gholamreza Bakhtiari, Ebrahim Alizadeh Doughikollaee, Mohsen Shahriari Moghadam, Mohsen Samimi,
Volume 29, Issue 6 (2-2021)
Abstract
The quality of fish flesh is affected by several factors including slaughtering methods and pre-slaughter conditions. In this study the effect of main operational variables such as fasting time (Xt), density (Xn) and fish weight (Xw) in the TBA value of common carp fillet has been evaluated and analyzed using the response surface method and Box-Behnken model. A numerical optimization model was performed to obtain the minimum amount of TBA in the fillets. Adapted fish treated by fasting time, density and weight and then harvested after 1, 4 and 7 days, slaughtered by smothering out of water and then fillet. The results showed that the lowest TBA value on the second-order model was obtained at low level of (Xn) (4 fish numbers), low level of (Xw) (500 g) and high levels of (Xt) (7 days fasting time). The optimal TBA value was determined 0.6842 by model which was measured 0.701 after the practical validation test in optimal condition which indicating the high accuracy of the model to determine the optimum pre-slaughter. Therefore, the results of this study showed that using the response surface method is appropriate to optimize pre-slaughter conditions of common carp and also the second-order model can be used to predict the response variable in difference conditions of pre-slaughter.
Maboud Alizadeh Noudeh, Jamileh Pazooki,
Volume 29, Issue 6 (2-2021)
Abstract
The present study aimed to identify, introduce and compare pseudoparasites in wild fish (Rutilus kutum and Mugilidae) and cage culture rainbow trout (Oncorhynchus mykiss) in the southern coast of the Caspian Sea. Wild fish specimens were collected from four stations in Anzali, Kiashahr, Chalus, Mahmoudabad and rainbow trout in three cages of Kiashahr, Abbasabad and Si-Sangan. After transferring the specimens to the laboratory, they were bioassayed and parasitological examination was performed on all internal and external organs. Free-living nematodes, pine pollen, pollen grain, protozoa, fungal spores, plant seeds, and filaments were isolated from fish as pseudoparasites. The highest percentage of pseudoparasites belonged to Pine pollen and was found in almost all fish organs. Free-living nematodes were isolated from the stomach, intestine, gills and Pollen grain from the liver, spleen, and kidneys of fish. Pseudoparasites are widespread in addition to they may be transmitted by food or randomly to fish. Pseudoparasites do not cause infection and disease in their host. Investigating and understanding them because of their importance in the parasitology can be useful for parasitologists and fish farmers to avoid the futile consumption of pharmaceuticals.
Sayed Ali Mousavi Golsefid, Shahram Abdolmalaki, Mohammad Reza Behrouz Khoshghalb, Jalil Jalilpour Roudkoli, Ali Hallajian, Mehdi Alizadeh Roudposhty, Mir Hamed Seyed Hassani,
Volume 30, Issue 2 (7-2021)
Abstract
The catch of the sturgeon has declined severely in the last two decades in the Iranian waters of the Caspian Sea. One of the methods for restocking and rehabilitation of the sturgeon stock, is releasing fingerlings and juveniles fish into the rivers leading to the Caspian Sea. In the present study, in order to a quantitative and qualitative evaluation of the sturgeon fingerlings released into the Sefidrood River, which included: stellate sturgeon (Acipenser stellatus), Persian sturgeon (Acipenser persicus) and Ship sturgeon (Acipenser nudiventris), growth indices, weight frequency percentage, growth rate, condition factor, average daily growth and survival percentage of released juveniles were studied during 2017-2018. The total of 1865506 fingerlings of sturgeon released in 2017 from Shahid Dr.Beheshti Sturgeon Restoration and Genetic Conservation Center which comprised Persian sturgeon with 69.3% and the average weight of 2.3±1.01 g, stellate sturgeon with 23.4% and the average weight of 2.34±1.06 g, and Ship sturgeon with 7.3% and the average weight of 5.61±2.56 g, and the total of 1609448 sturgeon fingerlings released in 2018 which included Persian sturgeon with 68% and the average weight of 1.65±0.75 g, stellate sturgeon with 25.5% and the average weight of 2.68±1.4 g, and Ship sturgeon with 6.5% and the average weight was 11.6±4.34g. Based on the Pearson correlation analysis, there were a negative correlation between the number of culture days for two species of Persian sturgeon and stellate sturgeon released during the years 2017-2018 in Sefidroud River and growth coefficient, condition factor, specific growth rate and daily growth rate at the end of rearing period (p<0.05). Also, the mean daily growth rate and specific growth rate of Persian sturgeon and stellate sturgeon fingerlings in 2017 were significantly higher (p<0.05) compared to 2018 and even in stellate sturgeon were higher than in Persian sturgeon.
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