Showing 3 results for Rutilus Caspicus
Sajad Fatahi, , , , ,
Volume 4, Issue 2 (9-2015)
Abstract
The effect of different levels of betaine and tryptophan on growth and resistance to salinities in the Caspian roach was investigated. Fish (1.90 ± 0.04 g body weight) were divided into 9 groups (4 treatments groups containing betaine (0.5 and 1), tryptophan (0.25 and 0.5), betaine and tryptophan mixtures (0.25- 0.5, 0.25, -1, 0.5-0.5 and 0.5- 1), and control group). After recording the growth factors, the fish were exposed to salinities (12, 16 and 20 ppt) and clinical symptoms and mortality rate were recorded. No mortality occurred in 12 ppt salinity. At 16 ppt, the lowest mortality (16.66%) was recorded in the treatment containing 1% betaine and 0.5% tryptophan, while the highest mortalty (59.98%) occurred in the control group. At 20 ppt salinity, 100% mortality occurred within 6 hours in the control, while in the other treatments 100%-mortality occurred after 24 hours. Behavioral symptoms, such as jerky movements, ataxia, increased respiratory rate, were more prominent in higher salinities. Tryptophan did not reduce food consumption meaningfully. Increaesd food consumption as the result of betaine did not show significant effect on the fish growth rate.
S. Ghorbani, D. Haghighi, H Maghsoodieh Kohan, D. Parvaneh Moghadam, S.m. Salavatian,
Volume 7, Issue 4 (12-2018)
Abstract
This study was carried out to evaluate the effects of dietary protein levels on growth performance and body composition of Caspian Roach (Rutilus caspicus) fingerling. Four experimental diets were formulated to contain protein levels of 30, 35, 40, and 45%. Triplicate groups of 300 Roach (Average weight, 2.65±0.17g) were stocked in 100L-fiberglass tanks (25 fish/tank) and were fed based on 3% of their biomass for 57 days. The results showed that weight gain (WG%), specific growth rate (SGR), food conversion ratio (FCR), condition factor (CF) and survival (SR%) were not affected by dietary protein level but the protein efficiency ratio of protein levels containing 30 and 35% CP was significantly higher than other dietary treatments (p<0.05).The body compositions were affected by dietary protein levels. Body protein significantly decreased with increasing dietary protein levels but body lipid increased when protein increased to 40% level. The results of the present study indicated that growth enhancement of fish was not significant when the diets protein levels were increased from 30 to 45%, but fish fed a diet containing 30% CP had greater protein efficiency values when compared to those fed with other diets.
Negin Amin, Seyedeh Ainaz Shirangi, Hadiseh Kashiri, Hojatollah Jafaryan, Hossein Adineh,
Volume 11, Issue 1 (3-2022)
Abstract
Because of the importance of osmoregulation in success of the juvenile Caspian Roach (Rutilus caspicus) release, maintenance and their restoration, this study was performed with the aim of the evaluation of these fish (average weight of 1.4 g± 0.018 g) to the salinity tolerance of the Caspian Sea by abrupt and gradual transfer methods on two different occasions of short-term (24 hours) and long-term (21 days). For this reason, 360 juvenile roaches were distributed to 9 different experimental treatments (each of them with 3 replicates) with 1) increased abrupt salinity (direct transfer to the Caspian Sea water), 2) increased gradual salinity (3 ppt for every 24 hrs) and 3) the Control group (freshwater). In order to evaluate the ion regulation, osmolality, Na+, K+ and Cl- were measured in fish. Some immune responses related to the increased salinity (immunoglobulin and lysozyme) and stress indices (cortisol and glucose) were also measured. Based on the obtained results, the fish in both treatments of increased salinity showed high percentage of survival. All parameters related to ion regulation were decreased after a primary increase. Furthermore, the trend of cortisol and immunoglobulin changes were negatively correlated showing decreased stress response and increased immune system for both salinity transfer methods. Thus, the roach juveniles (1-2 g) are able to be transferred into the Caspian Sea directly.
