Showing 10 results for Falahatkar
Sahar Biukani, Ali Safarpour, Bahram Falahatkar,
Volume 2, Issue 1 (6-2013)
Abstract
Fish fauna at three stations along the Gamasiab River, Kermanshah Province, were investigated for 9 months. Samples were caught using electroshocker and cast net of 1.5 cm mesh size and had their 20 morphometric and 10 meristic characteristics recorded. Twenty three species and subspecies in 14 genera and 5 families were identified, including: minnows (Cyprinidae), sisorid catfishes (Sisoridae), bagrid catfishes (Bagridae), river loaches (Balitoridae) and spiny eels (Mastacembelidae). The highest number of species (18, 78.3%) and genera (10, 71.4%) belonged to Cyprinidae, while 2 species (8.7%) in 1 genus (7.1%) belonged to Balitoridae; the other three families each contained 1 genus and 1 species (4.3%). The lowest species diversity (9 species) was observed in upstream station while the highest diversity (16 species) was in downstream station. Among the identified fish, only Pseudorasbora parva was recognized as exotic and the others were native.
Bahram Falahatkar, Samaneh Ghaderi,
Volume 2, Issue 2 (9-2013)
Abstract
Aquaculture production is often accompanied by some stressors which undesirable effects on growth and physiological function. Music is one of the cases that could eliminate or reduce the effects of stressors. The purpose of this study was to determine the effect of Iranian traditional music on growth, reproduction and behaviour of zebra cichlid (Pseudotropheus zebra). Fish with an average weight 5.5 0.18 g were put under both music and silence treatment with the number of 2 fish/aquarium with 3 replicates for 4 weeks. Fish under music treatment were put twice a day and every 30 minutes under the Iranian traditional music. At the end of this period, suitable conditions for fish were created to spawning. The results showed no significant differences in growth parameters, but 50 percent of fish during the 2-week were spawned in music treatment. However, only 16.6 percent of fish under silent treatment were spawned. Of eggs and spawn time, significant differences were observed between two groups. When is music being played, the fish were found mainly along approach the speakers, while the distribution of fish treated silence was uniform. The results of present study showed that use of music can affect physiological function of fish, which have more tranquility and less stress on fish.
Mohammad Sadegh Alavi-Yeganeh, Bahram Falahatkar,
Volume 2, Issue 3 (12-2013)
Abstract
Length-weight relationship, age range and fecundity of 40 specimens of the Russian sturgeon, Acipenser gueldenstaedtii, collected from two fishing stations in the southeastern Caspian Sea, were determined. Average length (TL) and weight were 129.5 cm and 12.7 kg for males and 145.8 cm and 22.15 kg for females, respectively. Absolute fecundity was 184000 in average and condition factor calculated 0/58 and 0/7 for male and females, respectively. Average age for males and females was 12.7 and 14.6 years, respectively. All these factors were lower than previous records from the Volga river estuary. Length-weight relationships results demonstrated isometric growth pattern with average slope of 2.978 and 2.822 for males and females respectively. These values were not statistically different between sexes (p> 0.05), but using this relationships for each sex separately will be useful for more reliable results especially in broodstock studies.
Mohammad Alavi-Yeganeh, Bahram Falahatkar,
Volume 3, Issue 1 (6-2014)
Abstract
Length-weight relationships and fecundity of 93 individual female Acipenser persicus broodstocks were investigated. The specimens were caught during 2001-2005 from Golestan, Mazandaran and Guilan provinces along the southern coast of the Caspian Sea. Total length and weight of each fish was measured to the nearest 1cm and 100 g, respectively. Age determination was carried out by using transects of the first ray of pectoral fin. The absolute fecundity was assessed by egg count per weight unit of all eggs existed in the body. The specimens were from 13 to 20 years old, of which the 16 years old had the highest proportion with 23.7%. Range of total length and weight were 132.5 to 211 cm and 14 to 42 kg, respectively. Mean absolute fecundity was estimated 267810 ± 92570. Total length, weight and absolute fecundity of fish increased with age in all cases, showed a significant positive correlation (p <0.01). The slope of the length-weight relationship (b) was equal to 2.745 and isometric growth pattern was determined in this species.
Z. Ghaderi , B. Falahatkar, H. Allaf Noveirian , A. Rahdari ,
Volume 8, Issue 1 (Winter 2019)
Abstract
The aim of the present study was to investigate the effects of ascorbic acid and density on reproductive performance and steroid hormones in rainbow trout (Oncorhynchus mykiss). In this regard, six treatments were considered included three diets containing 0, 100, and 1000mg ascorbic acid as L-ascorbyl-2-polyphosphate per kilogram of food in contrast to two densities 4.33kg/m3 and 2.16kg/m3. Triplicate groups of fish were fed one of the test diets for 16 weeks. A total of 81 females with an average weight of 812.1±1.5g were introduced to tanks (910 liters). At the end of the 16th week and when preparing fish for spawning, from each replication of high and low densities, 4 and 2 fish after bleeding of fish to measure the concentrations of progesterone, testosterone, and estradiol were spawned. After that, reproductive parameters such as work fecundity, ova per gram, and ova diameter were measured and then fertilized. During the incubation period, fertilization and mortality rates were recorded. The results showed the interaction between ascorbic acid and density and also the significance of this effect in reproductive parameters (number per gram of egg, oocyte diameter, coagulation, and fertilization percent; p<0.05). In the case of steroid hormones, the effect of treatments on the amount of each of the three hormones and their interaction on the level of estradiol and testosterone were significant (p<0.05), but the effect of density and diet on progesterone was not significant (p>0.05). The results of this study confirm the use of higher levels of ascorbic acid in breeders compared to grow-out period and also the positive role of this vitamin in reproductive indices.
M Abbasi, B Falahatkar, A Bani, B Heidari,
Volume 9, Issue 2 (Spring 2020)
Abstract
Temperature is the main environmental factor affecting the development of fish eggs. In this study, the effect of incubation temperature on fertilization rate, hatching rate and growth in goldfish (Carassius auratus) was investigated. Egg and sperm production were obtained by ovaprim injection and artificial propagation. Eggs were incubated at four temperatures (21, 24, 27 and 30 °C) with 3 replicates for each treatment and cultured for 40 days at the same temperature. The larvae were grown in the same aquarium that had been hatched under the same temperature condition for 40 days. The results showed that there was no significant difference in fertilization rate of incubated eggs at different temperatures, but the highest (97%) and lowest (94%) fertilization rates were observed at 24 °C and 21 °C, respectively. The maximum incubation time was recorded at 21 °C and the minimum time required at 30 °C (P < 0.05). The highest percentage of hatching (74.4%) was observed at 24 °C and it decreased with increasing water temperature (P < 0.05). Although, the temperature of 30 °C showed the highest value of length, weight and specific growth rate of larvae in comparison to other temperature treatments, but the highest anomalies (13%) were observed in this treatment, too. The best temperature of incubation and growth of larvae is 24°C and 27°C for goldfish, respectively.
Sara Pourhosein Sarameh, Bahram Falahatkar,
Volume 10, Issue 4 (12-2021)
Abstract
Targets:The objective of this study was to control the reproductive cycle and increasing the efficiency of the production of pikeperch (Sander lucioperca) through determining the effects of different photoperiods on reproductive performance and egg and larval quality.
Methods: Pikeperch broodstock with mean weights 1367 ± 55.3 g were exposed to three different photoperiods with light intensity 630 lux including constant light (24L), constant darkness (24D), and 12 h of light, 12 h of darkness (12L:12D) with three replicates for 40 days.
Results: The results showed that the pikeperch reproductive performance was affected by photoperiod. Broodstock under 24L spawned earlier than those of the other photoperiods. The highest spawning were observed in the morning in 24L (66.7 ± 3.5%) and the lowest spawning belonged to the 24D and 12L:12D that never spawned at night. Although fertilization rate and number of eggs per gram did not show any significant difference in various photoperiods, the timing of spawning and the egg quality exhibited remarkable difference.
Conclusion: The results of this study pointed out to effective application of photoperiod on changing the spawning time, reproductive and induction of out-of-season spawning of pikeperch broodstock. Additionally, these results unequivocally prove that the reproductive performance of pikeperch can be considerably improved and stimulated by an effective photoperiod.
Faezeh Mortezaei, Bahram Falahatkar, Mir Masoud Sajjadi, Roghieh Safari,
Volume 12, Issue 4 (12-2023)
Abstract
The objective of this study was to evaluate the performance of nutritional programming on growth and hematological indices of sterlet sturgeon (Acipenser ruthenus) during the larval stage by partial replacement of fish meal (FM) with soybean meal (S). Sterlet sturgeon with initial mean weight of 0.32 ± 0.01 g were randomly distributed into twelve circular concrete tanks (260 fish per each tank) and fed four experimental diets with substitution levels of 0 (control/FM), 15% (S15), 30% (S30) and 45% (S45) of fish meal with soybean meal during three phases in three replicates. In phase 1 (programming), fish were fed four different diets for 28 days. All the groups were then fed with FM during phases 2 (intermediate) and S45 at phase 3 (challenge) for 28 days. At the end of each phase, growth indices were measured. Hematological indices including red blood cell, hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration were assessed at the end of the challenge phase. The growth performance was not significantly different in either phases 1 or 2 (P > 0.05); however, final weight, weight gain, specific growth rate, and average daily growth were significantly higher in S45 than FM during phase 3 (P < 0.05). Moreover, no significant difference was indicated among the groups in hematological indices (P > 0.05). According to the obtained results, early nutritional programming could effectively enhance the adaptation of sterlet sturgeon to plant-based protein later in life.
Erfan Akbari Nargesi, Bahram Falahatkar, Daniel Zarski, Danial Gorouhi,
Volume 13, Issue 4 (11-2024)
Abstract
The present study aimed to investigate the effects of injecting different hormonal agents on sex steroids levels and biochemical parameters of the blood plasma in females Caspian roach (Rutilus caspicus). In order to perform the experiment, groups of five fish were injected intraperitoneally as follows: 1) two injections of Ovaprim (Ova), 2) two injections of Ovopel (Ovo), 3) a priming dose of Ovopel with a resolving dose of Ovaprim (Comb1), 4) a priming dose of Ovaprim with a resolving dose of Ovopel (Comb2), and 5) sterile 0.9% saline. According to the observations, the highest concentrations of progesterone and estradiol were measured in control group and concentrations of these hormones sharply declined after spawning in the experimental treatments (P < 0.05). Moreover, the lowest testosterone concentration was observed in the control group and after spawning, its concentration showed a significant increase in hormone-induced treatments (P < 0.05). The highest plasma glucose concentration was obtained in the control group, and the lowest concentration was observed in the Comb1 treatment (P < 0.05). No significant difference was observed between experimental treatments in the concentration of plasma biochemical parameters (P > 0.05). Overall, the present study showed that hormonal agents can significantly affect the levels of sex steroids in the blood plasma of Caspian roach breeders. These results showed the need to consider the proper induction strategies and welfare conditions of Caspian roach breeders in captivity.
Volume 23, Issue 4 (10-2023)
Abstract
Self-compacting concrete (SCC) is known for its outstanding characteristics such as superior mechanical and durability properties. Corrosion of rebar due to penetration of chloride ions in the reinforced concrete elements is of particular importance. Therefore, this issue in the SCC must be investigated. Pozzolanic materials could be used in the SCC to increase the resistance of concrete against chlorine ion penetration. In this research, effects of pozzolanic materials including micro silica, nano silica, fly ash, rice husk ash, as well as limestone powder on the mechanical and durability characteristics of self-compacting concrete placed in chloride environment have been studied. The results show that nano-silica increases the mechanical and durability characteristics of self-compacting concrete. Moreover, the SCC containing combination of nano-silica and pozzolanic materials has better properties than the one containing nano-silica.
