Showing 3 results for Nafisi Bahabadi
, Mahmoud Nafisi Bahabadi, , , ,
Volume 5, Issue 2 (9-2016)
Abstract
In the current study, the effect of fresh water and different salinities of 15, 35 and 50 ppt on growth, feeding, body composition, glucose and cortisol in Asian sea bass (Lates calcarifer); were investigated. 180 fingerlings with average weight of 34.36±0.41 gram in 12 circular fiberglass tanks with 300 liter volumes were administered. Feedinng was done to satiation twice a day for 30 days. At the end of the experiment, biometry carried out and plasma and carcass samples were collected for estimating blood biochemical parameters and whole body composition. The obtained results showed that freshwater treatment had a significant difference in growth and feeding performance with other treatments (p < 0.05). Also, the results of carcass analyze showed that freshwater treatment moisture percentage was significantly higher (72.07±0.11) compared to other treatments (p < 0.05). Glucose and cortisol value in 15 ppt treatment were significantly higher at 35, 50 ppt treatment and 35 ppt, freshwater treatment, respectively (p < 0.05). Overall, this study showed this species is able to tolerate changes in salinity in the surrounding medium from seawater to brackish water through a period of 30 days and successfully adapt to freshwater without showing mortality. But, it could not be a good case for culture in fresh water because of using high energy for osmoregulation in fresh water.
Aali Hosseini, Mahmoud Nafisi Bahabadi, Ebrahim Sotoudeh, Yaser Hemmat, Reza Ghorbani Vaghei,
Volume 5, Issue 4 (3-2017)
Abstract
This experiment was conducted to determine the effects of three binding agents, including corn starch, carboxymethyl cellulose (CMC) and urea formaldehyde (UFA) (in diets containing 42% soybean meal) on growth performance, pellet water stability and chemical composition of Litopenaeus vannamei. Shrimps with an average initial weight of 0.73 g stored in polyethylene tanks and fed experimental diets for 52 days (four treatments and three replicates). Biometric measurements of shrimp were carried out in two periods of 15 and 21 days. At the end of experiment results showed that the average final weight of shrimp fed the UFA binder is significantly lower than other treatments (p<0.05). Specific growth rate at three sampling periods (p<0.05) and at the end of experimental (p<0.01) was significantly affected by the type of binder, with the lowest SGR in UFA and highest in shrimps were fed control diet. Statistical analysis showed that chemical body composition of shrimp was not significantly affected by dietary treatments. In general, according to the results of diet stability, growth performance and feed utilization as well as shrimp body composition, corn starch is a good binder for whiteleg shrimp feed.
F. Hosseinpour Delavar , M. Nafisi Bahabadi , M. Mirbakhsh, Kh. Niknam, S.a. Johari, E. Mohammadi Baghmollaii ,
Volume 7, Issue 4 (Fall 2018)
Abstract
The use of environmentally friendly methods is one of the new approaches in combating pathogens in aquaculture systems. The purpose of this research was the possibility evaluation of indirect use of Ag-NPs-coated porous ceramic in water filtration of culture system of shrimp post-larvae to control Vibrio harveyi. In this study, Ag-NPs-coated filters were characterized by various analytical techniques such as FTIR, XRD, ICP, and SEM. In this study, the antibacterial activity of Ag-NPs-coated on porous ceramic against mentioned bacteria via in vitro experiments Zone of inhibition test and Test tub test were determined. Then porous ceramic filter media used for water treatment. Therefore, the performance of the Ag-NPs-coated on porous ceramics in removing pathogenic bacteria was studied in two phases: In the first phase, V. harveyi was inoculated to the water and efficacy of filters of inhibition of bacteria was evaluated via total count of bacteria in the test water; in the second phase, the performance of the Ag-NPs-coated on porous ceramic was tested in the presence of shrimp larvae and efficacy of filters in inhibition of bacteria was evaluated via total count of bacteria, mortality rate, clinical signs, and also hepatopancreas and muscle culture. Based on the results, the highest zone of inhibition obtained in presence of Ag-NPs-coated porous ceramic modified by an aminosilane coupling agent, 3-Amino-Propyl-Triethoxysilane (APTES; the samples were immersed in the silver colloidal solution for 24h). The results of the flow test showed the highest bacteria removal efficiency from water with complete removal of the targeted pathogen. In the second phase, the results indicated a significant difference in decreasing of water bacteria, shrimp mortality and disease symptoms in treatment containing silver compounds compare to controls. According to results, Ag-NPs-coated porous ceramic have a high bacteria removal efficiency for the disinfection of water of culture system of shrimp to control Vibrio harveyi.