Rahim Peyghan; Ala Enayati; Mostafa Sabzevarizadeh
Volume 4, Issue 3 , September 2013, , Pages 175-178
Abstract
Thyroid hormones (T3, T4) have marked effect on body metabolism and in controlling osmoregulation activity in fish. The aim of this study was to determine the effect of water salinity changes on thyroid hormones level and thyroid-stimulating hormone (TSH) of grass carp. For this purpose 120 grass carp ...
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Thyroid hormones (T3, T4) have marked effect on body metabolism and in controlling osmoregulation activity in fish. The aim of this study was to determine the effect of water salinity changes on thyroid hormones level and thyroid-stimulating hormone (TSH) of grass carp. For this purpose 120 grass carp were divided randomly in to four groups (10 fish in each group and three replicates per treatment). Three groups were held in three different salinities at concentrations of 4, 8 and 12 g L-1. The fourth group was reared in fresh water and considered as control. After three weeks blood samples were collected from the caudal peduncle vein. Then serum was separated and serum thyroid hormones and TSH were measured by LISA on Microwell plates. Our results indicated that the average of T3 levels in 4, 8 and 12 g L-1 groups were 0.43 ± 0.11, 0.22 ± 0.04 and 0.21 ± 0.04 μg dL-1, respectively. T3 levels in all experimental groups were significantly lower than those of control group (p < 0.05). Serum T4 level in 4, 8 and 12 g L-1 groups were 0.29 ± 62955/40.06, 0.24 ± 43129/50.05 and 2.85 7958/± 05768/40.55 μg dL-1, respectively. Thyroxine level was significantly higher only in 12 g L-1 group in comparison with the control and other experimental groups (p < 0.05). Thyroxine level in other groups had not any significant difference with the control group (p > 0.05). The level of TSH in salinities of 4 and 8 g L-1 groups was significantly higher than that of control group (p < 0.05). The results showed that increasing water salinity can have significant effect on thyroid activity by decreasing T3 and increasing T4 level in serum of grass carp in experimental condition.
Ala Enayati; Rahim Peyghan; Ahmad Ali Papahn; Gholam-Hosain Khadjeh
Volume 4, Issue 1 , March 2013, , Pages 49-53
Abstract
In this study the effects of salinity on the electrocardiogram and some of blood serum minerals in grass carp were investigated. For this purpose, grass carp were exposed to concentrations of 4, 8 and 12 g L-1 salinities and electrocardiogram of all fish was recorded. Blood samples were also collected ...
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In this study the effects of salinity on the electrocardiogram and some of blood serum minerals in grass carp were investigated. For this purpose, grass carp were exposed to concentrations of 4, 8 and 12 g L-1 salinities and electrocardiogram of all fish was recorded. Blood samples were also collected from all fish and serum minerals were measured. Our results indicated that mineral level in the studied groups was significantly different. The average of heart rate per minute in control group and 4, 8 and 12 g L-1 were 10.15, 10.06, 12.17 and 7.79 beat per min, respectively. In 8 g L-1 group only the average of QT and ST segment decreased significantly in comparison with the control group (p < 0.05). In 12 g L-1 group the average of heart rate per minute decreased significantly in comparison with 8 g L-1 group (p < 0.05) and no difference in the average of heart rate per minute was observed in all groups. The average of RR, PT and ST segment in the 12 g L-1 group were significantly more than the other groups (p < 0.05). The results showed that water salinity level increased to concentrations above 8 g L-1 can have significant effect on the electrocardiogram and mineral level of blood serum in grass carp. These changes are probably can be considered as one of the causes of impairment of health and death of this fish species in the salinities more than 8 g L-1 due to ion imbalance and cardiovascular disorders.