Study on Toxicity Tests of Net Protozoa to Brachionus Plicatilis

LIU Qing; SUN Zhixin; GAO Xin; LI Shuangyu; ZHANG Ying; GAO Mengchan

Abstract：This test through net protozoa to Brachionus Plicatilis via acute and chronic toxicity tests to study the net protozoa of Brachionus Plicatilis survival,growth and reproduction by protozoa.The test results show:net protozoa of Brachionus Plicatilis of 24hLC50 value is 422.63ug/L,48hLC50 value is 302.86ug/L,and through Turubell formula derived its security concentration 46.66ug/L.Brachionus Plicatilis protozoa total reproductive capacity reduces when net concentration increased,the number of days of survival decreases as the concentration increases,the number of days of prenatal development increases with the concentration of prolonged,average reproductive times and the numbers of each reproductive increased with the concentration increases.The total amount of reproduction in each test group has a significant different (P＜0.05) from the comparison group;except for survival for several days 10ug/L group,other groups has significant different from the comparison group (P＜0.05).Intrinsic growth rate rm,net reproductive rate R0 and the finite rate of λ is reduced as the concentration increases,generation periodicity T increases as the concentration increases.Each test group of rm,λ and R0 has significant different (P＜0.05) from the comparison group;The group of T low concentrations has no significant differences (P＞0.05) from the comparison group,more than 30ug/L concentration group has significant different (P＜0.05) from the comparison group.Research indicates:The net protozoa of 10ug/L low concentrations has little influence on number of days of survival Brachionus Plicatilis,prenatal development time,the average number of reproductive and each number of reproductive.That is:there is no significant differences (P＞0.05) from the comparison group,but it has influence on total amount of reproductive,intrinsic growth rate,net reproductive rate and finite rate,etc.differences between the comparison group was significantly (P ＜ 0.05).