Effects of salinity on feeding rhythm and feces excretion time of Monopterus albus.
盐度对黄鳝摄食节律和排粪时间的影响

An indoor experiment was conducted to study the effects of different salinity (0, 2, 4, 6, 8, 10 and 12 g x L(-1)) on the feeding rhythm and feces excretion time of feeding-domesticated Monopterus albus. The results showed that salinity had no significant effects (P > 0.05) on the feeding rhythm of M. albus, but the proportions of food consumption by M. albus were significantly different (P < 0.01) during different time sections. M. albus only had one peak of food consumption during the whole day, and its feces excretion was in batches which varied with salinity. There were three batches of feces excretion at salinity of 0, 2, 8, 10 and 12 g x L(-1), while four and five batches at salinity of 4 and 6 g x L(-1), respectively. At different salinities, the time of the same batch feces excretion was significantly different (P < 0.01), e.g., in control group, the time of first three batches feces excretion was delayed for 4-25 h, compared with that in other groups. These research results would provide theoretic basis for feeding management and water quality control in M. albus culture in saline-alkaline and bottomland water area.