The present study was to investigate the effects of different salinities (0 (control), 3, 6, 9, 12, 15‰) in striped catfish (Pangasianodon hypophthalmus) at larvae stage. Four-hundred individuals were randomly distributed to each 500-L composite tank (containing 250-L water) in triplicates. After 60 days, fish was sampled to determine survival rate, growth performance, hematological parameters, stress response indicators, and enzymatic activities. The results showed that the survival rate was highest in 6‰ (60.9%) and lowest in 15‰ (1.25%) (p<0.05). Fish exposed to salinities from 0 to 9‰ showed an increasing trend in growth. The osmolality of fish reared in 9 and 12‰ was significantly higher than that in the lower salinities (p<0.05). Similarly, concentrations of Na+, K+, and Cl- increased remarkably at high salinities. Chymotrypsin and trypsin activities were reduced by increased salinities (p<0.05), which were lowest at 15‰ (69.2±2.46 U/min/mg protein and 1.46±0.01 mU/min/mg protein, respectively). Stress indicators such as glucose and cortisol concentrations were not significantly depended on the salinity in the range of 0 to 12‰. Striped catfish larvae showed an adaptable response to high salinity and the appropriate salinity range for larvae rearing was below 6‰.
This study aimed to evaluate the effects of temperature on the growth and survival of mud crab (Scylla paramamosain) larvae in two stages including zoea-1 to megalopa (the first experiment) and megalopa to crablet-1 (the second experiment). Each experiment was conducted in a completely randomized design with four temperature levels (27, 30, 33, and 36℃) in triplicate. Stocking density of 200 ind./L for the first experiment and 4 ind./L for the second experiment. Fiberglass tanks of 500-L (containing 300-L and 250-L of 25‰ water for the first and second experiment, respectively) were used in the experiments. The results showed that S. paramamosain larvae at zoea-3 and zoea-4 died at 33℃ or above, while the highest survival rate of this stage was found at 27℃ (11.5%). The growth and larval stage index during the zoea to megalopa stage were significantly higher in 30℃ (p<0.05) compared to those in the 27℃ treatment. In the second experiment, the survival rates of crablet-1 were highest (72.9%) at 27℃ and lowest (34,7%) at 36℃. The growth rate of crablets at this stage increased with increased temperature. The highest carapace width and weight (3.41 mm and 0.030 g, respectively) were recorded at 36℃. The findings of this study suggested that mud crab larvae should be reared at the temperature range of 27-30℃ to maximize their production.
The effects of temperature on growth performance, survival rate, digestive enzymatic activities, and physiological responses of striped snakehead (Channa striata) at fry stage were evaluated. The study consisted of two trials including (1) determination of temperature threshold and (2) effects of different temperatures (24°C, 27°C (control), 30°C, 33°C and 36°C) on growth performance, survival rate, digestive enzyme activities and physiological parameters of striped snakehead fry stage for 90 days. The growth experiment was conducted in 500-L tank (250-L water) with triplicates. The stocking density was 300 individuals per tank. Striped snakehead at fry stage showed a high tolerance to temperature ranging from 10 to 40ºC. After 90 days, fish reared in 30°C performed the greatest weight and survival rate (13.1±3.12 g/fish and 15.5±4.63%, respectively). The number of red blood cells and hemoglobin concentrations increased with the increase in temperature. It was discovered that different temperatures (from 27 to 36°C) did not significantly influence the number of white blood cells, osmolality, and ion concentration of fish. Glucose and cortisol concentrations increased with temperature rises and peaked in fish reared at 36°C, while temperatures of 30oC and 33oC showed higher digestive enzyme activities. It proves that 30°C is the optimal level for striped snakehead fry rearing.
With the changing culture and abrupt shifts in the socio-economic and political layouts of our globalized world, the religious situation, too, undergoes major changes. The article analyzes the phenomenon of New Religious Movements (NRM) in its current socio-cultural and political context. After defining the guiding terminology relevant to NRM, we proceed to (1) show the historical roots of this new religious trend, (2) expose the existing diversity of NRM, (3) define their characteristic traits, and philosophical assessment of the phenomenon as a whole (rather than its specific beliefs or practices). The article ends with identifying potential social, psychological, and political impacts of the NRM, calling for epistemological humility on the side of philosophers, and critical openness and cautiousness on the side of governmental institutions.
Effects of guava (Psidium guajava L.) and bhumi amla (Phyllanthus amarus Chum et Thonn) on haematology and thermal stress mitigation of striped catfish (Pangasianodon hypophthalmus) were investigated. In a 42-day trial, fish were administered 4 diets as control (without extract), 0.2% P. guajava (Pg0.2), 0.5% P. amarus (Pa0.5), and a mixture of Pg0.2 and Pa0.5 (Mix). Fish were then subjected to temperatures of 27°C, 31°C, and 35°C for another 42 days. Haematological parameters were highest at 35°C, but these parameters were not significantly different from values recorded at 31°C on day 14 post-temperature challenge. The Pg0.2 diet modified red blood cells, haematocrit, and haemoglobin (p<0.05). The lowest glucose concentration was recorded in Pg0.2 (57.4±1.34 mg/100 mL) and Mix (58.9±1.87 mg/100 mL) groups after 14 days of thermal exposure. Glucose concentration surged on the third-day post-temperature challenge, then declined, and was maintained at 35°C until the end of the experiment which was not significant if compared to those at 27°C. Pg0.2 and Mix diets significantly reduced lipid peroxidation and enhanced catalase in gill and liver after 42 days. In the case average water temperature in the Mekong Delta remains below 35°C, the feeding diets for P. hypophthalmus administered Pg0.2 or...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2025 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.