抗生素利福平对萼花臂尾轮虫生命表参数的影响

以萼花臂尾轮虫(Brachionus calyciflorus)为受试动物,研究了在不同斜生栅藻(Scenedesmus obliquus)密度(1.0×10⁶,2.0×10⁶,4.0×10⁶个/mL)下,不同浓度(2.0,4.0,6.0,8.0,10.0μg/mL)的利福平溶液对萼花臂尾轮虫实验种群增长参数的影响.结果表明,与空白对照组及助溶剂对照组相比,1.0×10⁶个/mL藻密度下,各浓度的利福平显著提高了轮虫的后代混交率;2.0×10⁶个/mL藻密度下,2.0,4.0,10.0μg/mL的利福平显著提高了轮虫的內禀增长率,各浓度的利福平均提高了轮虫的后代混交率;4.0×10⁶个/mL藻密度下,各浓度的利福平均显著提高了轮虫的內禀增长率和后代混交率.藻密度为1.0×10⁶个/mL时,利福平浓度与轮虫的生命期望、世代时间、平均寿命和后代混交率间具有显著的剂量-效应关系;藻密度为2.0×10⁶个/mL时,利福平浓度与轮虫的后代混交率间具有显著的剂量-效应关系;藻密度为4.0×10⁶个/mL时,利福平浓度与轮虫的世代时间、净生殖率、內禀增长率和后代混交率间有显著的剂量-效应关系.

Effects of rifampicin on life table demography of Brachionus calyciflorus under different Scenedesmus obliquus densities

By means of life-table technique, the effects of rifampicin at 2.0, 4.0, 6.0, 8.0, and 10.0μg/mL on the population growth parameters of Brachionus calyciflorus under three Scenedesmus obliquus densities (1.0×10⁶, 2.0×10⁶and 4.0×10⁶cells/mL) were studied. The results showed that compared to the controls, rifampicin at all the test concentrations obviously promoted the proportion of sexual offspring under the algal density of 1.0×10⁶cells/mL (P < 0.05). When algal density was 2.0×10⁶cells/mL, rifampicin at 2.0, 4.0 and 10.0μg/mL increased the intrinsic rate of population increase (P < 0.05), and rifampicin at all the test concentrations also increased the proportion of sexual offspring. When algal density was 4.0×10⁶cells/mL, rifampicin at all the test concentrations obviously promoted the intrinsic rate of population increase and the proportion of sexual offspring (P < 0.05). There were significant dose-effect relationships between rifampicin concentration and the life expectancy at hatching, the generation time, the average lifespan, and the average lifespan of the rotifers fed on the 1.0×10⁶cells/mL of algae. When algae density was 2.0×10⁶cells/mL, there were significant dose-effect relationships between the concentration of rifampicin and the proportion of sexual offspring. When algal density was 4.0×10⁶cells/mL, there were significant dose-effect relationships between the rifampicin concentration and the generation time, the net reproductive rate, the intrinsic rate of population increase as well as the proportion of sexual offspring.