限食、复食对獭兔体温、体重和消化系统重量的影响

选择20只健康獭兔进行短期禁食复食的补偿生长试验,研究禁食后复食对獭兔体温、体重以及消化系统的影响。结果表明,对照组的体温保持在39～40℃之间,限食组体温在38—40℃之间;对照组的体重随饲喂时间的延长而明显增加,限食组体重增加缓慢：第一阶段对照组和限食组内脏器官重量差异不大,第二阶段限食组的重量始终低于对照组。本次试验结果属于部分补偿生长。     

Changes in ghrelin levels of plasma and proventriculus and ghrelin mRNA of proventriculus in fasted and refed layer chicks

This is a test-report of ghrelin levels in plasma and proventriculus, the glandular portion of the avian stomach, by using a specific radioimmunoassay for acylated ghrelin, as well as the expression of the ghrelin gene in the proventriculus after a 12-h fasting period followed by a 6-h feeding period with 6-day-old layer chicks. After fasting, the plasma ghrelin levels increased from 21.3 ± 4.5 to 32.9 ± 5.0 fmol/ml, but once refed it returned to the control value. After fasting, the ghrelin mRNA and the peptide levels in the proventriculus increased, and ghrelin mRNA levels remained high but once refed the ghrelin content returned to the control level. Furthermore, in order to examine the effect of increased circulating ghrelin on food intake, a bolus intravenous injection of 500 pmol of chicken ghrelin was given to 8-day-old chicks. The ghrelin injection did not cause any significant changes in food intake. These results indicate that the levels of ghrelin and its mRNA with layer chicks are altered according to the feeding state and this in a similar manner as has been observed in mammals. Unlike in mammals, an increase in circulating ghrelin does not cause the promotion of food intake in chicks.     

周期性饥饿对点带石斑鱼摄食和生长的影响

[目的]研究周期性饥饿对点带石斑鱼摄食和生长的影响。[方法]对点带石斑鱼幼鱼（初始体重23.97±3.97g）进行周期性饥饿＂饥饿1d喂食5d＂（S1F5）、＂饥饿1d喂食7d＂（S1F7）,对照组持续喂食。各组日投饵量占体重的2%,试验共进行48d。[结果]S1F5组和S1F7组的湿重特定生长率（SGRw）和增重率（WGR）均小于对照组,S1F5组的饵料湿重转化率（FCEw）低于对照组,而S1F7组的FCEw略高于对照组。[结论]周期性饥饿降低点带石斑鱼幼鱼的SGRw和试验结束时体重,而且饥饿频率越高越明显。点带石斑鱼幼鱼在周期性饥饿过程中的生长属不能补偿生长。