Analysis of sturgeon fishes reproduction statistics on the northern part of Alborz region

Out put of sturgeon fish hatcheries on the Northern provinces analyzed. Unfortunately, for many reasons such as decreasing of brood fishes ,unsuitable and unprofessional managements, lack of sufficient financial supports, ageing of laboratory and incubation instruments, unemployment of energetic expertise sturgeon propagation and restocking programmes get decreasing trends. Thus managers must planning for activating of sturgeon restocking and propagation subjects

The study of aquaculture potential of Bojnord and Jajarm cities (Northern Khorasan province)

This study investigates the potential of Bojnord and Jarjam cities (Northern Khorasan province) for developments of Aquaculture. First of all, the current condition of Aquacture and fish farms were montiroed and recorde. Then, the information on geology, weather and climate as well as water resources data were gathered and evaluated. Climatology, geology and distribution of water reseources (i.e. reviers, springs, wells, and aqueducts) were prepared using GIS software. Evaluation of selected water resources in study area revealed suitability for culture of cold water fishes. Potentialities of the water resources for aquacture production were determined according to the latest guidline of Shilat organization. The maps of production potentialities were prepared for each water resources

The study of annual cycle of gonads developments and sex steroids of gray mullet, Mugil cephalus in Golestan Province

Grey mullet, Mugil cephalus is one of the most famous and valuable fish on the fisheries and aquaculture industry. This species is the most suitable to introducing the southern, northern and central regions of our country due to high resistant to large variation of water salinity and temperature. On the monthly sampling period biometric data including total length and total weight recorded and length and weight classes for every sex were determined. To understanding of physiological functions and sexual development of reproductive organs, this investigation carried out with Grey mullet imported from Hong Kong by 1993. Findings of this research can be used for management of artificial breeding of this species. Daily variation of pond water temperature was recorded. Sex steroid hormones and other plasma metabolites such as Ca^2+, cholesterol, triglycerides and total proteins were measured by blood sampling. Gonad samples were prepared in order to histological studies. Oocyte growth was studied by measurement of egg diameters. Measured values of cholesterol, triglycerides of blood plasma revealed that these metabolites have seasonal variation and severely deposited on the summer and mobilized on the spawning seasons. Findings of this research suggested that egg diameters, values of sex steroid hormones (estradiol and progesterone) and Calcium concentrations of fish blood plasma shortening increased a long with day length shortening