Majidreza Khoshkholgh

Department of Fisheries, Faculty of Natural Resources, University of Guilan, Sowmeh Sara,Guilan, Iran.

[ 1 ] - Contribution to the molecular systematics of the genus Capoeta from the south Caspian Sea basin using mitochondrial cytochrome b sequences (Teleostei: Cyprinidae)

Traditionally, Capoeta populations from the southern Caspian Sea basin have been considered as Capoeta capoeta gracilis. Study on the phylogenetic relationship of Capoeta species using mitochondrial cytochrome b gene sequences show that Capoeta population from the southern Caspian Sea basin is distinct species and receive well support (posterior probability of 100%). Based on the tree topologie...

[ 2 ] - Expression of growth hormone gene during early development of Siberian sturgeon (Acipenser baerii)

The mRNA expression of growth hormone (GH) gene in early development stages of Siberian sturgeon was investigated using RT-PCR method. Samples were collected from unfertilized eggs up to 50 days post hatched (dph) larvae in 11 different times. Ribosomal protein L6 (RPL6) transcripts were used as the internal standard during quantification of GH mRNA expression. The results showed that the GH mR...

[ 3 ] - Genetic variation in the narrow-clawed crayfish (Astacus leptodactylus) populations as assessed by PCR-RFLP of mitochondrial COI gene

The genetic variation and population structure of narrow-clawed crayfish (Astacus leptodactylus) was examined by means of polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) analysis of the cytochrome oxidase subunit I (COI) of mitochondrial DNA. A total of 194 adult specimens were collected from seven sample sites including, two in the south Caspian Sea and one each...

[ 4 ] - Transcription of growth hormone mRNA as a molecular marker of egg quality in Siberian sturgeon (Acipenser baerii)

The Siberian sturgeon (Acipenser baerii) is an economically important species. Sturgeon stockassessment during fingerling production is considered to be one of the most difficult phases ofhatchery rearing. The present study investigated the expression of growth hormone (GH)mRNA in unfertilized eggs, fertilized eggs, eyed eggs (2 day before hatching), non-viable eggsand newly-hatched Siberian st...

[ 5 ] - تأثیر کاشت هورمون 11-کتوتستوسترون بر پارامترهای بیوشیمیایی و هماتولوژیک فیل ماهی (Huso huso) پرورشی در مرحله پیش زرده سازی

درک و فهم نحوه تنظیم فرآیند تولیدمثل ماهیان خاویاری یکی از پیش‌نیازهای تکثیر مصنوعی این ماهیان می‌باشد. هر چند هورمون 11-کتوتستوسترون (11-KT) در خون جنس ماده برخی ماهیان شناسایی شده ولی اهمیت این هورمون آندروژنی در فیل ماهی ماده تاکنون بررسی نشده است. به این منظور، اثر 11-KT در فیل‌ماهی‌های ماده مرحله پیش زرده ­سازی مطالعه شد. مجموعاً 12 ماهی با وزن متوسط 165±5580 گرم به 2 گروه تقسیم شده و در تا...

[ 6 ] - مقایسة خصوصیات اندازشی و شمارشی سیاه‌ماهی (Capoeta capoeta; Güldenstaedt, 1773) در بالادست و پایین‌دست سد منجیل و سد تاریک در رودخانة سفیدرود

این مطالعه به منظور مقایسة تفاوت‌های اندازشی و شمارشی سیاه‌ماهی Capoeta capoeta در سه نقطه در طول رودخانة سفیدرود که سدهای منجیل و تاریک در آن احداث شده‌اند به اجرا درآمد. در مجموع 100 قطعه ماهی شامل 40 قطعه مربوط به ایستگاه بالادست سد منجیل، 27 قطعه مربوط به ایستگاه پایین‌دست سد منجیل (بالادست سد تاریک)، و 33 قطعه مربوط به ایستگاه پایین‌دست سد تاریک با الکتروشوکر صید شدند. در این مطالعه 36 صفت...

[ 7 ] - The effect of dietary oxymetholone on growth, survival and reproduction of guppy (Poecilia reticulata)

To check the ability of guppy fish (Poecilia reticulata) to receive high dietary doses of oxymetholone hormone and its effects on growth parameters, survival and reproduction, 300 fish at the age of 10 weeks, with an average weight of 0.38 ± 0.09 g were randomly assigned to 5 treatments and 3 replications in 15 glass aquaria (100 liters volume). Hormone levels were considered as 5 different dos...

[ 8 ] - Effects of the color of the bedding of cultivated aquariums on growth, nutrition and biochemical body composition in freshwater prawn postlarvae (Macrobrachium rosenbergii(

In this study, the effect of the color of the bedding of cultivating aquariums (white, black, green, blue) on growth performance, nutrition and biochemical composition of the body of large freshwater shrimp (Macrobrachium rosenbergii) post larvae was investigated. All laboratory and experimental stages of this study were carried out in the fall of 1397 and for 60 days in an ornamental fish plan...