علوم زیستی دریا
Ashkan Banan; Mohammad Reza Kalbasi Masjidshahi; Mahmoud Bahmani; Mohammad Ali Yazdani Sadati
Abstract
The present study aimed to investigate effects of colored light and tank color on stress response of juvenile beluga, Huso huso, including the measurement of some sero-haematological parameters (Hemoglobin, hematocrit, cortisol, glucose, etc.) and carcass chemical analysis. The study was conducted at ...
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The present study aimed to investigate effects of colored light and tank color on stress response of juvenile beluga, Huso huso, including the measurement of some sero-haematological parameters (Hemoglobin, hematocrit, cortisol, glucose, etc.) and carcass chemical analysis. The study was conducted at International Sturgeon Research Institute in Rasht, Gilan, using 64 specimens for colored light treatments with initial weight 98.83 ± 1.42 (mean ± SE) g which were reared (in groups of 8) under white, red, green and blue light and using 48 specimens for tank color treatments with initial weight 98.46 ± 1.17 (mean ± SE) g which were reared (in groups of 8) in white, black and blue tanks, all for 12 weeks. Based on the obtained results, cortisol levels in fish reared under red and green lights were significantly higher so much so that in addition to stress and light color effects, their interaction was also significant (P< 0.05). The results also depicted that cortisol levels in fish reared in black tank were significantly lower so much so that in addition to stress and tank color effects, their interaction was also significant (P< 0.05). However, in regard to the other parameters- hemoglobin, hematocrit and carcass chemical analysis- no significant differences were observed. Reviewing the obtained results demonstrates that blue light and black tank by establishing comfort in beluga juveniles have positive significant effects on physiological conditions and spell better stress response.
علوم زیستی دریا
m t; m k; m a
Abstract
Esox lucius Linnaeus1758 is one of the economically valuable species of Caspian Sea. Genetic diversity of marine resources is of vital important in their management and protection. ; seven microsatellite loci were used to investigate the genetic variation of 60 samples of Esox in Amir and Anzali wetlands ...
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Esox lucius Linnaeus1758 is one of the economically valuable species of Caspian Sea. Genetic diversity of marine resources is of vital important in their management and protection. ; seven microsatellite loci were used to investigate the genetic variation of 60 samples of Esox in Amir and Anzali wetlands of Gilan. Results showed conspicuous genetic variation in regions using Fst, AMOVA and a relatively high level of gene flow was found among populations.The average observed and expected heterozygosity was 0.626 and 0.662 respectively. Assessment of Hardy-Weinberg equilibrium showed that all samples of studied showed significant deviations from Hardy-Weinberg equilibrium (p ≤ 0.05).There were evidences for genetic bottleneck in the populations. Cluster and molecular variance analysis showed two completely distinct population in these wetlands, and this subject must be considered by fishery organization to resource management of this species.
Ali Taheri; Mohammad Reza Kalbassi; Abdul Mohammad Abedian
Volume 11, Issue 2 , November 2012, , Pages 16-24
Abstract
Effect of transportation of rainbow trout gametes under moist oxygen packing at 1-2 °c on fertilization was studied. Gametes were transferred in polyethylene bags (20×18cm) containing 0, 25, 50, 75 and 100 % moist oxygen (in its free volume) and ten hours after transfer in a Styrofoam box with ...
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Effect of transportation of rainbow trout gametes under moist oxygen packing at 1-2 °c on fertilization was studied. Gametes were transferred in polyethylene bags (20×18cm) containing 0, 25, 50, 75 and 100 % moist oxygen (in its free volume) and ten hours after transfer in a Styrofoam box with thermo gel bags, fertilization were conducted in 25 treatments (in 3 replicates) and fertilized eggs were transferred to an incubator designed for rainbow trout with recirculation system (10°c). Percentage of fertility, eyed eggs, and hatching rate were calculated as an indicator for determination of optimum level of oxygen during transportation. The best results were obtained from fertilization of eggs transported at 100% oxygen and sperm transported at 75% oxygen with 95.01 ± 1.2% fertility, 78±4.21% eyed eggs and 75±3.88% hatching rate which were significant different (p<0/05) compared to the control (treatment without oxygen). As in fish breeding programs, gamete transfer is simpler and inexpensive than brood stock transfer, and hence this method could be applied for short term transferring of rainbow trout gametes as a simple and applicable method.
Iman Sourinejad; Mohammad Reza Kalbassi
Volume 11, Issue 2 , November 2012, , Pages 45-57
Abstract
Conservation of genetic diversity of juveniles used for restocking of natural populations requires serious attention in artificial breeding protocol of the Caspian brown trout Salmo trutta caspius. Unbalanced contribution of male and female breeders to progeny in present artificial breeding has resulted ...
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Conservation of genetic diversity of juveniles used for restocking of natural populations requires serious attention in artificial breeding protocol of the Caspian brown trout Salmo trutta caspius. Unbalanced contribution of male and female breeders to progeny in present artificial breeding has resulted in the reduction of effective population size in breeders. Equalization of milt volume did not also result in balanced contribution of breeders. With regard to the possible effect of sperm concentration on contribution of breeders to production of progeny, effective population size in breeders and genetic diversity of progeny were determined in mixed milt fertilization of 6 male and 2 female breeders with equal sperm concentration and ova number. Parentage assignment was performed using exclusion method in FAP program by analyzing 9 microsatellite loci and choosing the 3 most polymorphic ones, Str 58, Str 73 and Str 591, in breeders. More than 91% of progeny were assigned to their parents. Effective population size was calculated as 5.24 (0.65) and the number of alleles and expected heterozygosity decreased in progeny (6.67 and 0.726 ± 0.011) compared to parents (7.33 and 0.808) significantly (P>0.05). In conclusion, equalization of sperm concentration of male breeders did not result in the balanced contribution of male breeders to ova fertilization and production of progeny in mixed milt fertilization of Caspian brown trout and genetic diversity of progeny remained significantly decreased.