In this study the correlation between water physicochemical (EC, pH, salinity, hardness) andionic (Na+, K+, Ca2+ and Mg2+) parameters with growth indicators in Rutilus frisii kutum within 3 monthson 7 ponds (2 hectar) in Sijoval area in Golestan province were investigated. The range of water ioniccomposition were included (230-447.5 Mmol/l) Na+, (11.5-28.8 Mmol/l) K+, (0.04-22.44 mgr/dl) Ca2+and (12.47-22.45 mgr/dl) Mg2+. The pearson results were showed that there were significant correlationbetween first weight with Na+ and salinity (p<0.05), growth ratio with second weight (p<0.05), waterpH with k⁺, Na⁺, Mg²⁺ (p<0.01) hardness with hardness, Na⁺ and Ca²⁺ (p<0.01), salinity with k⁺ andNa⁺ (p<0.01) and Na⁺ with K⁺ (p<0.05). So, between water physicochemical and ionic parameters withgrowth indicators, significant correlation was showed that with management and regulation these factorsin suitable culture range, are caused growth increasing in R. frisii kutum.

Rutilus frisii kutum --- water physicochemical and ionic parameters --- growth

The effects of the composition of ceolomic fluid and sperm function are not well understood inteleostean fish species. The aim of the present study was to determine the concentration of the majorinorganic ions (Na⁺, K⁺, Ca²⁺+, Mg²⁺, Cl^-), organic composition (glucose and total protein) and pH ofovarian fluid in Prussian carp Carassius gibelio (Bloch, 1782), and to determine if the composition ofthese fluids influences sperm motility trait (percentage and duration of motility). In this purpose, spermmotility traits in 3 medium (ovarian fluid, fresh water + ovarian fluid and fresh water alone) were tested.The ovarian fluid was composed of sodium 133.1 ± 3.8 mM L^-1, potassium 2.4 ± 0.28 mM L^-1, calcium0.56 ± 0.28 mM L^-1, magnesium 0.65 ± 0.23 mM L^-1, chloride 135.4 ± 3.92 mM L^-1, total protein3.3 ± 0.46 gdL^-1, glucose 3.57 ± 0.48 mM L^-1 and pH 8.22 ± 2.9. The results suggested that spermmovement duration was significantly higher in ovarian fluid than fresh water and fresh water + ovarianfluid during spawning season. The percentage of motile spermatozoa did not differ significantly amongovarian fluid, fresh water + ovarian fluid and fresh water in spawning periods. As a conclusion, theresults of this study recommend the use of ovarian fluid, it is useful as an activation medium toimproving sperm motility parameters of Prussian carp.

Ceolomic fluid --- sperm motility --- Prussian carp --- season spawning

The aim of this study was evaluate the effects of dietary vitamin E on growth factors, survival,reproductive performance and sex ratio in guppy. Guppies were divided into 5 treatments with triplicategroups and fed with one of 5 diets for 20 weeks. The experimental vitamin E diets were formulated tocontain 100, 300, 500 and 1000 mg kg^-1 vitamin (treatment 1, 2, 3 and 4 respectively) with 1 controlgroup (Treatment 5). The data obtained from the trial were subjected to one-way analysis of variance(ANOVA) to test for effects of dietary treatments. In vitamin E treatments the body weight increase(BWI), percent body weight increase (PBWI), specific growth rate (SGR), daily growth rate (DGR) andreproductive performance of guppies were increased significantly with increasing the amounts of vitaminE (P<0.05) and highest BWI, PBWI, SGR and DGR were observed in treatment 4. There were nosignificant differences observed in survival rate and sex ratio between the treatments. This studyindicates that BWI, PBWI, SGR and DGR and reproductive performance can be improved by dietaryvitamin E supplementations and also may be concluded that the vitamin E requirement of guppies fishfor optimum growth and reproductive performance is 1000 mg kg^-1 of dry diet

Guppy --- vitamin E --- growth --- reproductive performance --- survival --- sex ratio

In this study we observed the influence of royal jelly on sex reversal in zebra fishes (Daniorerio). Experiments were made in the laboratories of aquaculture from Faculty of Animal Science andBiotechnologies, Timișoara in the period 01.03.2010 – 15.05.2010 on 225 individuals. The dinamics ofstandard body weight, the standard length and the maximum body high at all individuals from treeexperimental variants were evaluated. It was indentified the number of males and females by directexamination of the body and microscopic observation of histological samples. In the first experimentalvariant the food was mixed with 0.02 g powdered royal jelly and recorded at the end of the experiment70.76% females and 29.24% males. In the second experimental variant, a double dose of powderedroyal jelly was mixed in the feed, this leading to the increasing of females in the group to 81,19%. Inthe control variant the percentage of females was 50.7% and the percentage of males was 49.3%.

royal jelly --- zebra fish --- sexual inversion --- sex reversal

Access to peer-reviewed literature is often restricted to a limited segment of the target audience.Barriers are in place to prevent open access of information. In the applied research science of aquaculture,these barriers have slowed progress and innovation. Here, I present a case study of how the internet andhobbyists are transforming both access and flow of information from closed circles to open dialogue withinthe field of marine ornamental fish rearing. This open approach is leading to innovation a rate remarkablyfaster and at a lower costs than could have been accomplished by traditional methods. Aquaculturesocieties, aquarium professionals, hobbyists, and scientists pursuing the captive production of speciesshould embrace this movement. Whether production is for profit, conservation, or pure enjoyment, thefree flow of information provides exciting new opportunities.

open access --- marine ornamentals --- aquaculture