فهرست مطالب

علوم آبزی پروری ایران - سال یکم شماره 2 (پاییز و زمستان 1392)

نشریه علوم آبزی پروری ایران
سال یکم شماره 2 (پاییز و زمستان 1392)

  • تاریخ انتشار: 1392/11/20
  • تعداد عناوین: 6
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  • Jafarian H. *, Makhtomii M., Jafaryan S Page 3
    In this study the use of Daphnia sp and Artemia urmiana nauplii as live food for starting feeding of Starry Sturgeon (Acipenser stellatus) was investigated. Experiments were performed to determine the exploitation rate of Daphnia sp and Artemia urmiana nauplii by Starry Sturgeon larvae and to determine the best live food at first feeding stage. This experiment was conducted in a completely randomized design. Fish larvae in three experimental fed by Artemia nauplii¡ Daphnia and blend of Daphnia and Artemia having three replicates were fed based on the 30% of body weight day-1. After a 22-day rearing period¡ the proximate compositions of samples of fish were determined. The highest level of carcass crude protein (75.68%) and food conversion efficiency (41.13%) were obtained by the larvae receiving mixture of Daphnia sp and Artemia urmiana nauplii. At the end of the experiment¡ the larvae fed on Artemia nauplii and Daphnia sp a significantly higher mean weight compared to the other groups. Feeding of the larvae with Artemia urmiana nauplii resulted in a significantly lower carcass crude protein compared with the other treatments. During of experiment¡ among larvae groups¡ the maximum of survival rate (89.5%) was obtained by the larvae fed on Artemia nauplii. The results of the present study demonstrated that the exploitation ability of Acipenser stellatus larvae in using live food was different and the mixture of Daphnia and Artemia nauplii had almost the best feeding efficiency and they can be introduced as a suitable diet for rearing stages of Starry Sturgeon larvae.
    Keywords: Daphnia sp, Artemia nauplii, Starry Sturgeon, crude protein, survival rate
  • Tukmechi A. *, Manaffar R., Noori F Page 16
    Artemia is a good vector for transferring nutrient substances and different compound such as drugs¡ etc¡ into the aquatic larvae. The aim of this study was to optimize the enrichment method of Artemia urmiana nauplii with two probiotic bacteria¡ Lactobacillus rhamnosus and Bacillus subtilis. For the same purpose¡ at first stage¡ the effects of different salinities¡ temperature¡ and number of bacteria on enrichment of Artemia were studied. In the next stage¡ the best concentration of probiotics for enrichment of Artemia nauplii on the basis of first stage observation was investigated. The result obtained from this study revealed that optimum conditions¡ such as salinity¡ temperature¡ time intervals for addition of bacteria and number of probiotics are 30 ppt¡ 32˚C¡ 6 h and 106 CFU/ml for Lactobacillus rhamnosus and 40 ppt¡ 28˚C¡ 9 h and 107 CFU/ml for Bacillus subtilis¡ respectively. The result obtained from this study revealed that optimum conditions¡ depend on bacterial type was alter. On the basis of these findings¡ we conclude that in order to obtain maximum enrichment of a particular probiotic specific enrichment conditions must be provided.
    Keywords: Artemia urmiana, Enrichment, Probiotic, Optimization
  • Ghaderpour S. *, Agh N., Noori F., Ahmadian E Page 26
    In this study¡ the effects of enriching Artemia franciscana nauplii with three concentrations of Canola oil at three density levels were evaluated on survival¡ total length and fatty acids of Artemia franciscana nauplii to determine the optimum concentration oil¡ density of nauplii and optimum time for maximum survival rate and fatty acids and minimum total length of nauplii. Cysts of Artemia franciscana were hatched according to the standard method (Sorgeloos¡ 1986). Artemia franciscana nauplii were then stocked at densities of 50000¡ 100000 and 200000 nauplii L-1 in 7 L cylindrical containers. Canola oil emulsion was added at concentrations of 0.1¡ 0.2 and 0.3 g L-1 at the beginning and 12 hours after the onset of enrichment. Nauplii were sampled at 6¡ 12 and 18 h after onset of enrichment for measuring the survival¡ total length and the concentration of fatty acid. The results of analysis showed that enrichment of Artemia with 0.3 g L-1 Canola oil at 50000 nauplii L-1 for 18 hours was considered as best treatment. Artemia nauplii enriched in this treatment had maximum linoleic and linoleic acids¡ highest survival and minimum total length.
    Keywords: Artemia franciscana, enrichment, Canola oil, fatty acids
  • Rahdari A. *, Gharaei A., Ghaffari M., Pakzad S Page 40
    The present study was carried out to evaluate the effect of dietary lipid levels on growth performance¡ body composition¡ feed efficiency and blood metabolites of snow trout (Schizothorax zarudnyi) fingerlings. Ninety-six fish averaging 5.46±0.85 g were randomly distributed into 12 of 30 L aquariums (8 fish/aquarium). Triplicate groups of fish were fed for 56 days four isonitrogenous experimental diets (34.5% crude protein) comprising 1601-2026.1 kj digestible energy g-1¡ containing 5¡ 8¡ 12 or 15.5% crude lipids. There were significant differences in body weight increase¡ feed efficiency¡ protein efficiency¡ food conversion ratio and specific growth rate (P0.05). Whole body lipid significantly increased in fish fed 15.5% lipid diets than fish fed 5¡ 8¡ 12 and 15.5% lipid¡ but there was no significant difference in protein¡ ash and moisture. Among serum metabolites¡ only triglyseride showed significant differences among the four dietary lipid levels and in 5% diet was lower than others. In conclusion¡ diets with 5-8% lipid are able to provide suitable level of lipid for snow trout fingerlings.
    Keywords: Snow trout, lipid, growth index, blood metabolites
  • Kiani S., Farhadian O.*, Mahboobi Soofiani N Page 51
    The density¡ growth and cellular morphology in green algae Scenedesmus quadricauda (Chlorophyceae) population were investigated at different concentrations of 0¡ 5¡ 10¡ 50¡ 100¡ 200 and 500 mg/l of Cadmium in this study. The experimental conditions for culture of this species were included of culture medium of Bold Basal’s Medium¡ temperature of 25 ºC¡ light regime of 12 hours light: 12 hours dark¡ and light intensity of 60 µmol photons/m2/s. The experiment was carried out as completely randomized design for a 14-day period. Results showed that increment of population density of S. qaudricauda cultured with increase of concentration of Cd¡ significant decrease during experiment. The lowest cellular density (9.33 × 104 cell/mL)¡ minimum specific growth rate (0.009 /day) and maximum population doubling time (79.2 days) were obtained at 500 mg/l of Cd concentration. Cellular morphology (based on cells per colony) of S. qaudricauda population was considerably changed during experiment. The relative colony formation at lower of Cd concentrations dominated by only 1 cell/colony while the cell composition in the higher concentrations were tendency to more than 1 cell/colony. In overall¡ the response of S. qaudricauda to Cd concentrations increasing was to decrease in population.
    Keywords: Algae, Scenedesmus quadricauda, Cadmium, Colony formation, Specific growth rate
  • Dehmarde H.*, Gharaei A., Ghaffari M Page 63
    In this study investigated the effect of different levels of carbohydrate in artificial diets on growth parameters and body chemical analysis of Snow trout juveniles (Shizothorax zarudnyi) in 8 weeks. Hundred fifty Snow trout juveniles with average weight 3.54±1.14 g and length 8.5±2.4 cm fed with five isonitrogenous and isolipidic diets and varying levels of carbohydrates (16.59%¡ 22.2%¡ 26.99%¡ 32.9% and 36.77% ). Ten advanced fry were stocked into each 45-l aquaria with triplicate in five treatments and fed twice daily at 5% body weight rate. Results indicated highest body weight gain (2.83±0.02)¡ specific growth rate (1.05±0.03)¡ average daily gain (5.06±0.05)¡ protein efficiency ratio (0.71±0.01) ¡ feed efficiency ratio (0.25±0.01) and lowest feed conversion ratio (3.94±0.04) observed in D4 treatment that fed by diet containing 32.9% carbohydrate that no significantly difference with D5 treatment that fed by diet containing 36.77% carbohydrate while significantly differences with other treatment (p˃0.05). Also there were no significant differences in wet and ash demand of carcass treatment fed by various levels of dietary carbohydrate¡ while lipid and protein in carcass in treatment that fed by diet containing 32.9% and 36.77% carbohydrate increase and decrease respectively (p˃0.05). Finds of this study indicated that best containing diet carbohydrate for optimal growth and nutrition indexes in Snow trout juveniles is 32.9% to 36.77%.
    Keywords: nutrition, growth, carbohydrate, Snow trout (Shizothorax zarudnyi)