Fisheries
seyedeh abedi; mohammad khalesi; Sohrab Eskandari
Articles in Press, Accepted Manuscript, Available Online from 01 December 2013
Abstract
This research aimed at comparison of chromium bioaccumulation patterns in skin, gills, scales, liver and muscle of two widely-consumed fishes: scaled common carp Cyprinus carpio and scaleless catfish Pangasius hypophthalmus. First, lethal concentration (96 h LC50) of chromium as well as its toxicity ...
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This research aimed at comparison of chromium bioaccumulation patterns in skin, gills, scales, liver and muscle of two widely-consumed fishes: scaled common carp Cyprinus carpio and scaleless catfish Pangasius hypophthalmus. First, lethal concentration (96 h LC50) of chromium as well as its toxicity factor (TF) was determined for each species. For bioaccumulation trial, the two species exposed to sublethal concentrations (10% of LC50 values) of Cr at separate triplicate treatments for 15 days. The examined tissues from each species were sampled at days 7 and 15 of the experiment. Following chemical digestion, each tissue was analyzed by atomic absorption unit (Model Thermo) to measure chromium concentration. According to the results, Almost all differences in bioaccumulations between the two species and the controls were significant (p < 0.05). Concentration of chromium in common carp was in the form of gills> liver> skin> scales> muscle, and accumulation in catfish was in the form of liver> muscle> skin> gills. Final entire contents of Cr in the catfish's tissues were 3.65 times, than in the carp’s (excluding the scales). In addition, the catfish's muscle amassed 16.15 times greater amounts of Cr.The results of this investigation indicate that the carp's scaled armature, compared to the scaleless skin of the catfish, adsorbs metal toxicants leading to much lesser metals content in the muscle rendering this tissue rather safer for comestible consumption.
Fisheries
Reza Dehghan; Mohammad Khalesi; Sohrab Kohestan Eskandari
Abstract
Beluga (Huso huso) is one of the most important commercial fish in the Caspian Sea, whose reproduction and breeding, as well as caviar extraction, are of special importance. This study was conducted to investigate the morphological analysis for non-invasive sex determination in this sturgeon species ...
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Beluga (Huso huso) is one of the most important commercial fish in the Caspian Sea, whose reproduction and breeding, as well as caviar extraction, are of special importance. This study was conducted to investigate the morphological analysis for non-invasive sex determination in this sturgeon species to replace the invasive methods in the event of appropriate outcomes. A total of 180 fish were biometried at the Sea Abzigostaran Center, Sari, within 2 weeks. The samples were then photographed and the photos were analyzed by the TPS (transection processing system) technique for sex determination. The ANOVA test showed homogeneity of morphormetric data. Leven's test showed that all the morphometric traits had uniform variances (P ≥ 0.05). The analysis of the distinctive function for morphometric traits indicated that 100% of both male and female beluga samples displayed their characteristics. Overall, the results of this test revealed that on average 100% of the males and females were grouped accurately, which indicates the separation of the sexes based on this test. The UPGMA dendrogram for morphological traits based on the mean correlation showed that the samples of beluga were partially distinguished from each other by gender. However, the TPS technique could distinguish the male and female beluga samples, thus, it could be considered a non-invasive method for the sex determination of sturgeon fish.
