| In this paper, I used the Chinese crocodile lizard (Shinisaurus crocodilurus) which is preserved as the first class protected animal in China as a model animal to study the trait of thermal ecology and its breeding technique. The main results and conclusions are summarized as the following:I. Thermal requirements in Shinisaurus crocodilurusResults showed that in the wild, active body temperature (Tb) of Shinisaurus crocodilurus was higher than substrate temperature (Tc) and air temperature (Td) regardless of population or individual, or the whole active period or months. The active body temperature of the ?lizard in wild showed the monthly difference, and not difference among ages or between sexes. In laboratory of 15℃-30℃, the body temperature in resting (Tb) was positively correlated with ambient temperature (Ta): Tb =12.450 +0.5641 Ta (F1, 110 =11.34, r2 =0.997, P <0.001). In the environment with thermal gradients, there was significant diel variation in body temperature, air temperature and substrate temperature, but the body temperatures were significantly higher than air temperature and substrate temperature. In the environment without thermal gradients, there was significant diel variation in body temperature, air temperature and substrate temperature, but there were no significant differences in daily means of body temperature, air temperature and substrate temperature. The RMR showed no difference between sexes, and it increased with ambient temperature (Ta). Further analysis indicated that the thermoregulation of Chinese crocodile ?lizard was conducted by both behavioral and physiological, and both thermoregulation and the resting metabolic rates of Chinese crocodile ? lizard were accorded with the thermal biology of ectotherm. The capability of physiological thermoregulation of Chinese crocodile ?lizard was relatively higher than these of other more active lizards. The thermoregulation of Chinese crocodile ?lizard was accorded with its behavioral characteristics that spent the most time on rest. The selected body temperatures (Tsel) and resting metabolic rates (RMR) of the Chinese crocodile lizard were different among different ages. The higher Tsels and RMRs were chosen in gravid females, one-year-old juveniles and two-year-old juveniles. However, Tsels and RMRs were not significantly different among males, non-gravid females and three-year-old juveniles. It was presumed that for Chinese crocodile lizard, it would cost about 3 years before mature. It was suggested that an optimal thermal environmental conditions should be maintained for the gravid females and the juveniles for better growth and development under artificial condition.Body temperatures affected food passage time, daily food intake, apparent digestive coefficient (ADC) and assimilation efficiency (AE). Food passage time decreased as the body temperature increase range from 22℃to 34℃. Daily food intake, ADC and AE were lower at 22℃than these at any other temperature. The Locomotor performances showed no difference between sexes. The one-year-old juveniles show more faster sprint speed, more stops in the racetrack and more length of continuous locomotion while there no different between the juveniles and the adults. Sprint speed of adults increased with body temperature within the range from 20℃to 28℃, and then decreased at 28℃. Sprint speed of juveniles increased with body temperature within the range from 20℃to 30℃, and then decreased at 30℃. Sprint speed of one-year-old juveniles increased with body temperature within the range from 20℃to 34℃. Swimming stamina of adults and juveniles were better than gravid females and one-year-old juveniles. Swimming stamina of gravid females and one-year-old juveniles increased with body temperature within the range from 22℃to 30℃, and then decreased at 30℃. But swimming stamina of adults and juveniles increased with body temperature within the range from 22℃to 34℃.II. Specific dynamic action in Shinisaurus crocodilurusThe experimental animals were divided into 4 groups, including Group A feeding Tenebrio molitor larvae, Group B feeding Pheretim a, Group C feeding Pheretim a double times and the control group. In the single meal experiment, two different types of food were fed, food ingested by Shinisaurus crocodilurus of the two experimental groups differed significantly in wet mass, dry mass and energy content. Food passage time of Shinisaurus crocodilurus feeding Tenebrio molitor larvae (Group A) and Pheretim a (Group B) was 81.15±3.82 h and 50.41±3.91 h, respectively. Food passage time of Group A was significantly longer than that of Group B. Temporal variation in oxygen consumption over 96 h after feeding was evident in the ingesting lizards but not in the unfed controls, suggesting that feeding exert an effect on metabolic rate (and thus, SDA) in Shinisaurus crocodilurus. Oxygen consumption was significantly higher in the Group A (feeding Tenebrio molitor larvae) than in the control ones within the time interval from 8 h- 31 h after feeding. Group B (feeding Pheretim a) consumed significantly more oxygen than did control group during the period between 8 and 24 h following feeding. The duration of the SDA was significantly longer in Group A (feeding Tenebrio molitor larvae) than in Group B (feeding Pheretim a). The Peak VO2 of SDA, factorial increase, total oxygen consumed of SDA and total energy expended of SDA all differ significantly between Shinisaurus crocodilurus feeding the two different types of food, but these difference was absent when the influence of variation in ingested energy was removed. Time to peak VO2 and SDA coefficient both not differ significantly between Shinisaurus crocodilurus feeding the two different types of food.In the double meal experiment feeding Pheretim a, temporal variation in oxygen consumption over 96 h after the initial feeding was evident in the Group C (double meal) but not in the control ones. The first peak metabolic rate occurred at 8 h after the initial feeding, whereas the second peak metabolic rate at 32 h. Oxygen consumption was significantly higher in the Group C (double meal) than in the control ones within the time interval from 4-54 h after the initial feeding. Lizards in the double meal experiment ingested more energy and hence had a prolonged duration of the SDA effect than did those in the single meal experiment, but the magnitude of the SDA effect did not significantly differ between both experimental treatments when the influence of variation in ingested energy was removed.These results show that food type and feeding frequency have different influence on the SDA of animals, but the magnitude of the SDA effect remained nearly constant when the influence of variation in ingested energy was removed. Therefore the energetic cost associated with ingestion is mainly determined by energy content of food ingested by animals. When comparing these data with the corresponding data collected in other species, we find that the time to reach a peak of SDA, duration of SDA, the peak of SDA and SDA coefficient differ considerably among species.III. The breeding technique of Shinisaurus crocodilurusThe breeding technique of Shinisaurus crocodilurus is very important to its conservation. An adequate water supply, a favorable temperature and humidity, a quiet environment and ample food were indispensable for breeding Shinisaurus crocodilurus. It should be fed separately and scientifically in accordance with its different development stage and different experimental purposes. At the same time, we should control breeding density, accelerate the establishment of development records for Shinisaurus crocodilurus and intensify the prevention of epidemics.
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