Studies On The Ingestive Physiology And Metabolic Physiology Of Cyclina Sinensis And Its Enegy Budget

The ingestion rate, filtration rate, absorption efficiency, respiration rate and excretion rate are measured under different temperature, salinity, pH and food concentration conditions, the energy budget equations were built. The main results were as follows:1. The effects of temperature on the feeding physiology, metabolic physiology and energy budget of Cyclina sinensis with varied dry tissue weightThe ingestion rate, filtration rate, respiration rate and excretion rate had been measured at four levels of temperature (20, 25, 30 and 35℃) and the energy budget equations were built. The results showed that the effects of dry tissues weight on both ingestion rate and filtration rate were significant(P<0.01). The peak of ingestion rate and filtration rate appeared at 30℃. The maximum values of ingestion rate of three body sizes were 20.61±1.61mg/g.h, 11.30±1.14mg/g.h and 6.31±0.97mg/g.h respectively; the maximum values of filtration rate of three body sizes were 4.90±0.38 L/g.h, 2.68±0.27L/g.h and 1.50±0.23L/g.h respectively. Both respiration rate and excretion rate increased with the raising of temperature but decreased with the increasing body size. Relationship between respiration rate, excretion rate and dry tissue weight were expressed as: Y=aWb, the mean values for b were 0.598±0.063 and 0.554±0.024, respectively.The equations which dry tissue weight was 0.06±0.01g were as follows: 20 ℃: 100025.61R+1.48U+23.19F+49.72P 25℃: 100C=20.38R+1.37U+17.58F+60.68P 30℃: 100C=39.50R+1.89U+28.59F+30.02P 35℃: 100C=75.75R+3.64U+51.23F-30.62PThe equations which dry tissues weight was 0.238±0.045g were as follows: 20℃: 100C=29.15R+1.57U+24.54F+44.73P25℃: 100C=24.86R+1.42U+17.83F+55.89P 30℃: 100C=33.53R+1.77U+31.34F+33.35P 35 ℃: 100C=78.13R+3.90U+46.24F-28.27PThe equations which dry tissue weight was 0.601±0.093g were as follows: 20℃: 100C=30.06R+1.56U+24.25F+44.13P 25℃: 100C=29.26R+1.59U+18.38F+50.77P 30℃: 100C=34.47R+1.76U+33.51F+30.25P 35℃: 100C=74.67R+3.19U+45.03F-22.89P2. The effects of salinity on the feeding physiology, metabolic physiology and energy budget of Cyclina sinensisThe ingestion rate, filtration rate, respiration rate and excretion rate had been measured at four levels of salinity (14, 23, 32 and 41) , and the energy budget equations were built. Ingestion rate reached the maximum value of 18.37±1.92 mg/g.h at salinity 32, then decreased sharply. Filtration rate reached the maximum value of 5.10±0.10 L/g.h at salinity 23. The peak of respiration rate appeared at salinity 32 as well as the excretion rate, the value were 3.70±0.40mg/g.h and 10.26±1.48umol/g.h respectively. Respiration rate decreased sharply if the salinity exceeded 32, excretion rate was the same as respiration rate but decreased smoothly.The energy budget equations at four levels of salinity (14, 23, 32 and 41) were listed as follows:14: 100C=12.24R+0.67U+34.69F+52.40P 23: 100C=14.37R+1.04U+21.48F+63.12P 32: 100C=20.38R+1.37U+17.58F+60.68P 41: 100C=l 1.32R+0.98U+54.30F+33.40P3. The effect of food concentration on the feeding physiology of Cyclina sinensisThe ingestion rate and filtration rate had been measured at five levels of food concentration (1.12±0.31, 2.01±0.43, 4.25±0.34, 6.94±0.81 and9.28±1.47mg/L) , the results showed that the increase of food concentration caused the increase in both ingestion rate and filtration rate. The ingestion rate and filtration rate reached the maximum values of 27.45±1.83mg/g/h and 14.27± 1.48L/g/h when the foodconcentration was 9.28±1.47mg/L. The relationship between ingestion rate , filtration rate and food concentration were expressed as: IR=6.66 C0 0.65 (R2 = 0.89); FR = 1.43 C01.08 (R2=0.88).4. The effect of pH on the metabolic physiology of Cyclina sinensisThe respiration rate and excretion rate had been measured at six levels of pH(6.6, 7.1, 7.6, 8.1, 8.6 and 9.1) , the respiration rate showed two peaks whichappeared at pH 7.1 and pH 8.6, and the two values were 3.43±0.24mg/g.h and4.70±0.48mg/g.h respectively. The excretion rate increased with the pH 6.6-8.6, andthe maximum value was 8.04±0.35umol/g.h, then deceased from pH 8.6- 9.1.5. The effect of salinity on asphyxiation point of Cyclina sinensis.The samples are collected at various times(0, 2, 6, 12, 36, 48, 72, 144, 216 and 288h) under different salinity conditions (14, 23, 32 and 41) . The pH, dissolved oxygen and asphyxiation point had been measured. Asphyxiation point were 1.232mg/L at salinity 14, 0.832mg/L at salinity 23, 0.758mg/L at salinity 32, 0.652mg/L at salinity 41. The earlier Cyclina sinensis started to die, the higher the dissolved oxygen level in Asphyxiation point, the dissolved oxygen at the salinity of 41 is almost twice as much as that at salinity 23.