علوم زیستی دریا
Ebrahim Alizadeh Doughikollaee; Mohammad Nouri; Naser Agh
Volume 11, Issue 2 , November 2012, Pages 1-7
Abstract
Effect of salinity levels on density and population growth of parthenogenetic Artemia were studied. Cysts were hatched and 200 nauplii were transferred into cylindro-conical containers (1.5 liter) containing one-liter water at different salinities (50, 100, 150, 200 and 250 ppt) and cultured until maturity. ...
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Effect of salinity levels on density and population growth of parthenogenetic Artemia were studied. Cysts were hatched and 200 nauplii were transferred into cylindro-conical containers (1.5 liter) containing one-liter water at different salinities (50, 100, 150, 200 and 250 ppt) and cultured until maturity. After maturity, 3 female parthenogenetic Artemia wereselected randomly from each of the five levels of salinity and cultured in 4 replicates for 12 weeks. The growing Artemia were categorized into four population groups (1) nauplii and meta-nauplii, (2) juvenile Artemia (3) pre-adult Artemia, and (4) adult Artemia and were counted once a week. Results showed that the density of adults, nauplii and meta-nauplii were higher in 100 ppt. The maximum population of pre-adult and juvenile Artemia were found at 50 ppt. The density of adult Artemia increased while density of other categories decreased during culture period. Based on our findings, an inverse relationship between salinity and population of parthenogenetic Artemia were observed. Results indicated that lower salinities are more suitable for population growth of parthenogenetic Artemia.
Ali Reza Shamoradi; Mohammad Ali Salari-Aliabadi; Seiied Mohammad Bagher Nabavi; Ahmad Savari; Abdolali Movahedinia
Volume 11, Issue 2 , November 2012, Pages 8-15
Abstract
The goals of this study were identification and ecological survey on macrobenthic bivalves in the Khark Island. This study has been done during four seasons through 2010-2011 in five sites around the Khark Island. In each five sites, three separated transects including supralittoral, eulittoral and sublittoral ...
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The goals of this study were identification and ecological survey on macrobenthic bivalves in the Khark Island. This study has been done during four seasons through 2010-2011 in five sites around the Khark Island. In each five sites, three separated transects including supralittoral, eulittoral and sublittoral zones have been selected. At each sampling time and site environmental factors such as temperature, salinity and total organic maters (TOM) have been measured. Collected samples were analysed and according to the results, Maximum and minimum water temperatures have recorded in summer (35.94 ± 0.28) and in winter (18.34 ± 0.39) and the Maximum and minimum rates of salinity have recorded in winter (44.6 ± 0.14) and spring (37 ± 0.18) respectively. Maximum and minimum percentages of total organic maters (TOM) have observed in summer (9.63 ± 0.71) and winter (3.39 ± 0.15) respectively. Twelve bivalve species belonging to seven families were identified that are: Barbatia lacerate, Pinctada radiate, Ostrea sp.1, Crossostrea gigas, Sacosstrea cucullata. Diplodonta ravaiyensis, Venus sp.1, Circentia callypyga, Callista sp.1, Gari roseus, Tellina capsoides, Angulus adensis. The maximum and minimum density and distribution have been found in spring and summer respectively. In our study the most frequent bivalve species in all seasons was Barbatia lacerate.
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.
Samaneh Poursaeid; Bahram Falahatkar; Iraj Efatpanah
Volume 11, Issue 2 , November 2012, Pages 25-35
Sara Jorjani; Abdolmajid Hajimoradloo; Afshin Ghelichi; Noor Mohammad Makhdoomi; Rezvanollah Kazemi
Volume 11, Issue 2 , November 2012, Pages 36-45
Abstract
Microscopic structure of intestine of beluga was studied from hatching until releasing to sea. Larvae were fixed in bouin’s solution, dehydrated and embedded in paraffin wax. Sections of 5-7 μm thick were produced and stained according to standard histological techniques: Hematoxylin-Eosin ( ...
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Microscopic structure of intestine of beluga was studied from hatching until releasing to sea. Larvae were fixed in bouin’s solution, dehydrated and embedded in paraffin wax. Sections of 5-7 μm thick were produced and stained according to standard histological techniques: Hematoxylin-Eosin ( HαE ) and Periodic Acid Schiff ( PAS ). One day old larvae possessed a primordial intestine, which is lined by a simple columnar ciliated epithelium. At 3 days after hatching, an oblique furrow of the digestive tube wall started to develop on the dorsal- posterior region of the yolk sac and divided the alimentary canal into two differentiated regions: the future stomach and intermediate intestine. At this time spiral valve started to differentiate. Granules of embryonic pigment accumulated in the spiral valve lumen forming the melanin plug. At 7 days after hatching intermediate gut and spiral gut were lined by a columnar ciliated epithelium. The terminal section of the digestive tract was differentiated into a short rectal duct lined with a cuboidal epithelium. The urinary bladder connected with rectum at this time. At 13 days after hatching the number of vacuoles filled with lipid increase in intermediate gut and spiral gut. Between 17-19 days post hatching beluga larvae have a period of mixed nutrition. At 25 days after hatching cells of intermediate gut showed long microvilli. At 36 days after hatching the number of goblet cells increased in spiral gut. At 43 days after hatching several intestine glands were visible in connective tissue of intermediate gut which was lined by a simple columnar ciliated epithelium. Between 57-75 days after hatching the number and size of mucosal folds increased in intestine. This information may be useful to improve rearing efficiency of beluga and the other sturgeons.
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.
Mohammad Zakeri; Peseta Kochanian; Jasem Marammazi
Volume 11, Issue 2 , November 2012, Pages 58-66
Abstract
The crude protein content and amino acid compositions of muscle from wild and cultured of male and female Acanthopagrus latus were determined by HPLC. There were quantitative differences between individual amino acids in the tissues investigated, depending on the sex and location. It was noted that, ...
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The crude protein content and amino acid compositions of muscle from wild and cultured of male and female Acanthopagrus latus were determined by HPLC. There were quantitative differences between individual amino acids in the tissues investigated, depending on the sex and location. It was noted that, among all the samples studied in tissues, sexes and locations, lysine and isoleucine were the principal essential amino acid (EAA) and glutamic acid was mainly for non-essential amino acid (NEAA). Lysine and isoleucine of male muscles had a significantly higher (P<0.05) amount than female muscles. The crude protein content in male and female muscles was not found to be significantly different. Depending on location, the percentages of arginine, leucine, isoleucine, lysine, serine, glycine, alanine and tyrosine were significantly different (P<0.05) in muscles of wild and cultured fish. The wild seabream possessed considerably higher protein content than cultured seabream muscle. The results showed that wild male fish muscle contained a higher (P>0.05) level of EAA than other groups. The results indicate that the Acanthopagrus latus is a healthful component of the human diet.