Showing 3 results for N. Mahboobi Soofiani
N. Mahboobi Soofiani, O. Farhadian,
Volume 6, Issue 4 (winter 2003)
Abstract
To determine the effects of spawning frequency and density of incubating eggs on the survival rates of eggs and larvae in rainbow trout, five different groups of broodstocks with varying spawning frequencies were stripped. After fertilization, the percentage of survival at different stages of development, from eying, hatching to free swimming fry stages and also growth rates of larvae were determined. Moreover, the effects of incubating egg density (4000, 7000, 10000 per tray) on the different developmental stages of egg through free swimming larvae for each group of broodstock was studied. The study was carried out in a completely randomized design as a 5*5*3 factorial arrangement with three replicates. The results indicated that survival and growth rates are significantly correlated with spawning frequency (P<0.05) so that, survival and growth rates from fertilization to free swimming fry in broodstocks at their third and fourth spawning period were significantly different from the results obtained for broods in the first, second and fifth or higher spawning periods (P<0.05). Although the holding densities had no significant effects on the growth rate of larvae from different broodstocks, the survival rates from fertilization to free swimming stage was affected by incubating density so that the significantly lower value was recorded for density of 4000 per tray (P<0.05). In general, the results indicate that eggs obtained from broodstocks at their third and fourth spawning years have a better performance than those obtained from younger and older spawners. Also, the low holding density of eggs could decrease the performance of the fertilized eggs during incubating period.
N. Mahboobi Soofiani, S. K. Allameh Fani, Z. Faizi, J. Pourreza,
Volume 7, Issue 1 (spring 2003)
Abstract
The present experiment evaluated the effects of fat (Kilka fish oil) levels (0, 5, 10, 15 and 20%) in the diet (35% constant protein) on performance of rainbow trout. The experiment was performed in a completely randomized design, with 4 replicates, 200 grower fish with an average weight of 200±11 gr, each. They were randomly divided into 20 groups of 10 fish per group reared in separate pens. Fish were acclimated to the experimental conditions for 10 days before treatments began and then the experiment was performed over a period of 8 weeks. Measured criteria were weight gain (WG), specific growth rate (SGR), feed conversion ratio (FCR), condition factor (CF) and flesh chemical composition (fat, protein, ash), and fat stored in liver. Results showed that the diet with 15 percent fat content had significantly (P<0.05) better WG and FCR than other diets, but no significant differences were observed for SGR and CF. Diets with 15 and 20 percent fat contents caused the highest fat content in meat and liver and showed significant differences (P<0.05) with the meat and liver fat content in fish fed fat-free diets. Diet with 15 percent fat content caused significantly (P<0.05) lowest protein content in meat. No significant differences were observed in the ash content of the flesh. From the results of the present study, the level of 15 percent Kilka fish oil is recommended for the rainbow trout diet.
F. Shir-Mohammad, N. Mahboobi Soofiani, J. Pourreza,
Volume 8, Issue 4 (winter 2005)
Abstract
In order to investigate the effect of phytase and copper supplementaion on growth and carcass composition of common carp (Cyprinus carpio L.), in a completely randomized design with 3 ×2 factorial arrangement with three replicates the experimental diets including three levels of phytase 0, 500 and 1000 (FYT) kg-1 and two levels of copper 0 and 15 mg/kg were tested. Diets contained 0.72 percent total phosphorus. One hundred and forty four carps with a mean weight of 207±23 g were selected and allocated in eighteen cages (8 fish per cage). The experiment was carried out for 8 weeks and 2 weeks for acclimatization. Phytase supplementation caused no significant differences in weight gain (WG), feed conversion ratio (FCR), carcass index (CI), protein efficiency ratio (PER), liver, carcass and blood composition but increased apparent phosphorous digestibility (APD) significantly (P<0.04). Copper supplementation also caused no significant differences in WG, FCR, CI, PER, APD, liver copper, carcass composition, cholesterol (Ch), triglycride (TG), phosphorus of serum but decreased liver fat significantly (P<0.004) and increased high density lipoprotein (HDL) of serum (P<0.02). Interactions between phytase and copper on WG (P<0.01), FCR (P<0.04), PER (P<0.03), liver copper (P<0.02) and TG of serum (P<0.001) were significant. This experiment suggests the presence of antagonistic effect between phytase and supplemental copper. Phytase enzyme improved some parameters of growth and carcass composition of common carp without supplemental copper but addition of copper to the diets with phytase enzyme impaired the improved performance of carp.
