The effect of particle size on feeding rates in the rotifer Brachionus manjavacas
Major
Biology
Submission Type
Poster
Area of Study or Work
Biology
Expected Graduation Date
2022
Location
CNS Atrium, Easel 18
Start Date
4-9-2022 11:15 AM
End Date
4-9-2022 12:30 PM
Abstract
Rotifers are small planktonic animals that occur in marine and freshwater environments. Swimming and feeding by rotifers is accomplished by two bands of ciliated cells that surround the mouth. To understand how the rates of particle capture change with particle size, rotifers (Brachionus manjavacas) were exposed to 4.5 and 1.0 micrometer (μm) polystyrene beads (∼18,633 beads/mL for 4.5 μm beads; ∼50,000 beads/mL for 1.0 μm beads). After a 10-minute incubation period, the specimens were preserved and examined with transmitted light and fluorescence microscopy, and the number of beads present within the digestive tract of each rotifer counted. These data were used to calculate the clearance rate of each individual (mL of water processed per hour). During separate exposures, the average clearance rates of 4.5 μm beads were significantly lower than that of 1.0 μm beads. When B. manjavacas were simultaneously exposed to beads that differ in size and concentration, the clearance rates did not differ. There was no significant difference between the clearance rates of 4.5 μm beads measured separately or in a mixture. However, the clearance rates of 1.0 μm beads were significantly lowered when measured in the presence of the larger beads. These results suggest that there may be alternative mechanisms employed by rotifers to capture food particles differing in size.
The effect of particle size on feeding rates in the rotifer Brachionus manjavacas
CNS Atrium, Easel 18
Rotifers are small planktonic animals that occur in marine and freshwater environments. Swimming and feeding by rotifers is accomplished by two bands of ciliated cells that surround the mouth. To understand how the rates of particle capture change with particle size, rotifers (Brachionus manjavacas) were exposed to 4.5 and 1.0 micrometer (μm) polystyrene beads (∼18,633 beads/mL for 4.5 μm beads; ∼50,000 beads/mL for 1.0 μm beads). After a 10-minute incubation period, the specimens were preserved and examined with transmitted light and fluorescence microscopy, and the number of beads present within the digestive tract of each rotifer counted. These data were used to calculate the clearance rate of each individual (mL of water processed per hour). During separate exposures, the average clearance rates of 4.5 μm beads were significantly lower than that of 1.0 μm beads. When B. manjavacas were simultaneously exposed to beads that differ in size and concentration, the clearance rates did not differ. There was no significant difference between the clearance rates of 4.5 μm beads measured separately or in a mixture. However, the clearance rates of 1.0 μm beads were significantly lowered when measured in the presence of the larger beads. These results suggest that there may be alternative mechanisms employed by rotifers to capture food particles differing in size.