Study of fungicidal properties of colloidal silver nanoparticles (AgNPs) on trout egg pathogen, Saprolegnia sp.

Silver nanoparticles (AgNPs) are known to have bactericidal and fungicidal effects. Since, there is few information available on the interaction of colloidal nanosilver with fish pathogens. Hence, the current study investigated the effects of colloidal AgNPs on the in vitro growth of the fish pathogen Saprolegnia sp.. Before the experiments, various important properties of AgNPs were well-characterized. The antifungal activity of AgNPs was then evaluated by determining the minimum inhibitory concentrations (MICs) using two-fold serial dilutions of colloidal nanosilver in a glucose yeast extract agar at 22ºC. The growth of Saprolegnia sp. on the AgNPs agar treatments was compared to that of nanosilver-free agar as controls. The results showed that AgNPs have an inhibitory effect on the in vitro growth of the tested fungi. The MIC of AgNPs for Saprolegnia sp. was calculated at 1800 mg/L, which is equal to 0.18 percent. It seems that AgNPs could be a proper replacement for teratogenic and toxic agents, such as malachite green. In addition, the indirect use of AgNPs could be a useful method for providing new antifungal activity in aquaculture systems

Parentage assignment of progeny in mixed milt fertilization of Caspian brown trout Salmo trutta caspius using microsatellite DNA markers: Implications for conservation

Parentage of a stock of mixed milt produced progeny in current artificial breeding protocol of endangered Caspian brown trout, Salmo trutta caspius, was determined using three microsatellite loci chosen after a primary analysis of genetic diversity at nine microsatellite loci in the eight used breeder individuals. Overall, 98.8% of progeny were assigned to their parents using Family Assignment Program (FAP). Selection of hyper-variable microsatellites in Caspian brown trout to identify unique alleles was effective for unambiguous parentage determination and estimation of genetic diversity in this study. Effective population size of breeder individuals (Ne) was lower than the number of breeder individuals used (Nb) indicating unbalanced contribution of breeder individuals to progeny. Indeed, one of the four male breeder individuals produced about 70 % and the other three produced only from 4.86 % to 18.83 % of progeny. The average observed and expected heterozygosity of progeny (0.723 ± 0.011 and 0.684 ± 0.009, respectively) was significantly lower than that of their parents (0.833 and 0.800, respectively). Our data indicate that the current breeding protocol of Caspian brown trout may not provide equal opportunity for all the breeder individuals to contribute equally to progeny. Therefore, appropriate fertilization designs in the hatchery should be established in order to equalize the genetic contribution of different breeder individualsS

Mixed milt fertilization of endangered Caspian brown trout Salmo trutta caspius influences effective population size of breeders

The maintenance of the endangered Caspian brown trout Salmo trutta caspius populations in Iran depends on its artificial breeding. There is no information on how current hatchery breeding protocol influences effective population size of breeders (Ne), which is a critical parameter to maintain genetic diversity in future generations. The current hatchery protocol (CHP) was comparatively evaluated with a balanced hatchery protocol (BHP), where mixtures of equal amounts of gametes per male and female breeder were used to balance parental contributions to progeny. To evaluate putative differences in viability between families, individual crosses were performed and fertilized ova of different families were mixed to constitute balanced family pools. 1440 alevins were totally sampled in the crosses performed from the 11 breeders. An exclusion-based parentage approach using three polymorphic microsatellite markers unambiguously assigned more than 93% of progeny to a single pair of parents. Significantly different contributions of breeders to progeny were observed in CHP (p<0.05). The primary constraint on Ne in BHP was the unbalanced contribution of males, which seemed a consequence of sperm competition in mixed fertilization caused by differences in sperm quality. Sperm motility duration was positively correlated with the number of sired progeny by each male. The results illustrate the limitations of the BHP in minimizing the loss of genetic diversity observed in CHP. A protocol based on mixture of equal number of fertilized ova from individual male × female crosses emerged as the best alternative for conservation of Caspian brown troutS

Effect of Water Salinity on Acute Toxicity of Colloidal Silver Nanoparticles in Rainbow Trout (Oncorhynchus Mykiss) Larvae

Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 Background and Objectives: Nanotechnology defined as understanding and controlling of materials at dimension between 1-100 nm, which show unusual physical and chemical properties. With Increasing development of nanotechnology, concerns associated with release of materials containing nanoparticles into the environment is rising. The purpose of this study is investigation of salinity effect on the acute toxicity of silver nanoparticles in rainbow trout fry (Oncorhynchusmykiss). Materials and Methods: In order to conduct the toxicity tests, the Caspian Seawater(12&amp;plusmn;0.2 ppt) and (0.4 ppt) as sources of brackish water and freshwater were used, respectively. Toxicity of silvernano particles were evaluated in brackish water and freshwater at concentrations of1, 2, 4, 8, 16, 32and64ppm and&amp;nbsp; 0.12, 0.25, 0.5, 1, 2, 4 and8 ppm, respectively. In addition, in order to investigate the quality of the used silver nanoparticles the Zetasizer, ICP, and TEM method were applied.Results: Results of 96-hour median lethal concentration(LC50 96h), showed that toxicity of silver nanoparticles for rain bow trout fry in brackish water is 12 times less than its toxicity in freshwater.Conclusion: According to the toxicity categories, analysis of the results showed that, for rainbow trout fry (1g), silver nanoparticles are classified as highly toxic agent substances in fresh water, and little toxic in brackish water, respectively. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;

Study of fungicidal properties of colloidal silver nanoparticles (AgNPs) on trout egg pathogen, Saprolegnia sp.

Silver nanoparticles (AgNPs) are known to have bactericidal and fungicidal effects. Since, there is few information available on the interaction of colloidal nanosilver with fish pathogens. Hence, the current study investigated the effects of colloidal AgNPs on the in vitro growth of the fish pathogen Saprolegnia sp.. Before the experiments, various important properties of AgNPs were well-characterized. The antifungal activity of AgNPs was then evaluated by determining the minimum inhibitory concentrations (MICs) using two-fold serial dilutions of colloidal nanosilver in a glucose yeast extract agar at 22ºC. The growth of Saprolegnia sp. on the AgNPs agar treatments was compared to that of nanosilver-free agar as controls. The results showed that AgNPs have an inhibitory effect on the in vitro growth of the tested fungi. The MIC of AgNPs for Saprolegnia sp. was calculated at 1800 mg/L, which is equal to 0.18 percent. It seems that AgNPs could be a proper replacement for teratogenic and toxic agents, such as malachite green. In addition, the indirect use of AgNPs could be a useful method for providing new antifungal activity in aquaculture systems

Study of fungicidal properties of colloidal silver nanoparticles (AgNPs) on trout egg pathogen, Saprolegnia sp.

Silver nanoparticles (AgNPs) are known to have bactericidal and fungicidal effects. Since, there is few information available on the interaction of colloidal nanosilver with fish pathogens. Hence, the current study investigated the effects of colloidal AgNPs on the in vitro growth of the fish pathogen Saprolegnia sp.. Before the experiments, various important properties of AgNPs were well-characterized. The antifungal activity of AgNPs was then evaluated by determining the minimum inhibitory concentrations (MICs) using two-fold serial dilutions of colloidal nanosilver in a glucose yeast extract agar at 22ºC. The growth of Saprolegnia sp. on the AgNPs agar treatments was compared to that of nanosilver-free agar as controls. The results showed that AgNPs have an inhibitory effect on the in vitro growth of the tested fungi. The MIC of AgNPs for Saprolegnia sp. was calculated at 1800 mg/L, which is equal to 0.18 percent. It seems that AgNPs could be a proper replacement for teratogenic and toxic agents, such as malachite green. In addition, the indirect use of AgNPs could be a useful method for providing new antifungal activity in aquaculture systems