علوم زیستی دریا
Shahram Behmanesh; Bagher Amiri Mojazi; Abdolmajid Haji Moradlo; Mahmoud Bahmani; Fereidoon Chakmehdouz Ghasemi; Sohrab Dejandian
Abstract
The ovarian histological characterization of European Catfish on Anzaly lagoon was investigated. 154 female’s specimen in different size were caught by trap, ovarian were fixed in bouin׳s liquid. Samples were fixed, dehydrated, clarified, embedded and stained by H&E method. The tissues were ...
Read More
The ovarian histological characterization of European Catfish on Anzaly lagoon was investigated. 154 female’s specimen in different size were caught by trap, ovarian were fixed in bouin׳s liquid. Samples were fixed, dehydrated, clarified, embedded and stained by H&E method. The tissues were supplied on 0.5µ size and analyzed by light microscope. The ovaries had six maturity stages which were as follow: Immature, Early Developing, Late Developing, Ripe Ovary, Running Ripe Ovary and Spent. Oocyte diameter was measured for 123 female’s specimen in the 2 to 5 maturity stages. In this study, the mean egg diameter, in stage II of gonad maturation was 1/4 mm and gradually increased in the later stages of development, in the fifth stage of the maturation process the average diameter reached to 2/36 mm and again in the sixth stage decreased the oocyte diameter. Also according the present study the type of gonad in this species under the climatic condition of Guilan Province was found on Group Synchronous and spawning in longer period.
علوم زیستی دریا
Mehrdad Sarkheil; gholamreza rafiee; mehrdad farhangi
Abstract
In this study, effects of four concentrations of waterborne calcium (8, 25, 50, 100 mg/l) on eyed egg percentage, hatching percentage and ions (Ca, K, Cu and Mn) uptake of rainbow trout eggs in a water recirculating system were determined. Twelve experimental units, with the capacity of holding 45 liter ...
Read More
In this study, effects of four concentrations of waterborne calcium (8, 25, 50, 100 mg/l) on eyed egg percentage, hatching percentage and ions (Ca, K, Cu and Mn) uptake of rainbow trout eggs in a water recirculating system were determined. Twelve experimental units, with the capacity of holding 45 liter of water were used and 21g egg introduced in each one. Different concentrations of ions (Ca,Na,K,Mg,P,Fe,Cu,Zn,Mn) in treatments were prepared by adding analytical salts (Merck) into double-de-ionized distilled water. Dissolved oxygen and water temperature variations during incubation were 9.80-11.11mg/l and 7.5-9 ºC respectively. The eyed egg percentage was not significantly (P>0.05) different among treatments. The hatching percentage of eggs were significantly (P
Samaneh Poursaeid; Bahram Falahatkar; Bagher Mojazi Amiri
Volume 12, Issue 1 , April 2013, , Pages 90-105
Abstract
The objective of this study was to examine the effects of triiodothyronine (T3) implantation on the performance of physiology of cultured great sturgeon (Huso huso). Three treatments with 5 fish for each treatment were considered. The experimental treatments included: control (capsules containing cocoa ...
Read More
The objective of this study was to examine the effects of triiodothyronine (T3) implantation on the performance of physiology of cultured great sturgeon (Huso huso). Three treatments with 5 fish for each treatment were considered. The experimental treatments included: control (capsules containing cocoa butter alone), low level of T3 (T1; 1 mg T3/kg body weight + cocoa butter), and high level of T3 (T10; 10 mg T3/kg body weight+ cocoa butter). The capsules containing hormones and cocoa butter were intraperitoneally implanted to 3-year-old pre-vitellogenic stage female fish (mean initial body weight 6999.7±100.9 g) every 6 weeks over a six month period from January 2009 to June 2010. The serum levels of some hormone (T3, cortisol, ACTH) and biochemical parameters (glucose, cholesterol and calcium) were determined at the initial time and three weeks after each implantation. Growth indices (WG, SGR and CF) were determined at the end of the experiment. The results showed that fish treated with the high and low T3 doses produced significant changes in thyroid hormone levels (P<0.05). Serum cortisol was significantly higher in T3- implanted fish than in control fish (P<0.05). Serum glucose and calcium concentrations were significantly greater in fish treated with the high T3 doses compared to the other two experimental groups (P<0.05). Significant differences were observed in serum ACTH and cholesterol concentrations among treatments in the last and second sampling time, respectively (P<0.05). Final weight was the highest in T1-implanted fish; intermediate in those implanted the high T3 dose, and lowest in controls (P<0.05). These results indicated that the long-term implantations of T3 hormone influence the physiological parameters of great sturgeon and promote the somatic growth in a physiological dose.