Hayashi-Martins L H, Mansano A S, Hisatugo K F, Rocha O, Seleghim M H R
Laboratório de Ecologia de Microrganismos Aquáticos - LEMA, Departamento de Ecologia e Biologia Evolutiva - DEBE, Universidade Federal de São Carlos - UFSCar, Rodovia Washington Luís, SP 310, Km 235, CEP 13565-905, São Carlos, SP, Brazil.
Laboratório de Limnologia, Departamento de Ecologia e Biologia Evolutiva - DEBE, Universidade Federal de São Carlos - UFSCar, Rodovia Washington Luís, SP 310, Km 235, CEP 13565-905, São Carlos, SP, Brazil.
Braz J Biol. 2017 Nov;77(4):840-847. doi: 10.1590/1519-6984.02716. Epub 2017 Mar 16.
Cladocerans occupy an important position among the bacterial consumers in freshwater food webs, being relatively non-selective filter feeders that can exert a strong impact on microbial populations. We evaluated the bacterivory potential of three cladocerans species of subtropical and tropical occurrence (Ceriodaphnia silvestrii, Daphnia gessneri and Ceriodaphnia cornuta) at different life stages, by scanning electron microscopy (SEM) and by the quantification of their bacterial consumption rates using fluorescently labeled bacteria (FLB). All species showed filter mesh sizes sufficiently narrow to retain bacteria. The largest distance between setules was found in primiparous C. cornuta, and the smallest in neonate D. gessneri. The lowest ingestion (IR) and removal (RR) rates were observed in primiparous C. silvestrii and the highest values were observed in adults of D. gessneri. We conclude that bacteria may be considered an important food supplement, particularly for neonates who presented smaller intersetular distances and higher filtration rates than the other life stages.
枝角类动物在淡水食物网中的细菌消费者中占据重要地位，它们是相对无选择性的滤食者，能够对微生物种群产生强烈影响。我们通过扫描电子显微镜（SEM）以及使用荧光标记细菌（FLB）对三种亚热带和热带地区出现的枝角类动物（西尔维斯特仙达溞、格斯纳水蚤和角突仙达溞）在不同生命阶段的噬菌潜力进行了评估，并对它们的细菌消耗率进行了量化。所有物种的滤网尺寸都足够窄以保留细菌。在初产的角突仙达溞中发现刚毛之间的最大距离，而在新生的格斯纳水蚤中最小。在初产的西尔维斯特仙达溞中观察到最低的摄食率（IR）和清除率（RR），而在格斯纳水蚤成虫中观察到最高值。我们得出结论，细菌可被视为一种重要的食物补充，特别是对于新生个体而言，它们的刚毛间距比其他生命阶段更小，过滤率更高。
