A high-throughput method to quantify feeding rates in aquatic organisms: A case study with Daphnia

Jessica L. Hite, Alaina C. Pfenning-Butterworth, Rachel E. Vetter, Clayton E. Cressler

Research output: Contribution to journalArticle

Abstract

Food ingestion is one of the most basic features of all organisms. However, obtaining precise—and high-throughput—estimates of feeding rates remains challenging, particularly for small, aquatic herbivores such as zooplankton, snails, and tadpoles. These animals typically consume low volumes of food that are time-consuming to accurately measure. We extend a standard high-throughput fluorometry technique, which uses a microplate reader and 96-well plates, as a practical tool for studies in ecology, evolution, and disease biology. We outline technical and methodological details to optimize quantification of individual feeding rates, improve accuracy, and minimize sampling error. This high-throughput assay offers several advantages over previous methods, including i) substantially reduced time allotments per sample to facilitate larger, more efficient experiments; ii) technical replicates; and iii) conversion of in vivo measurements to units (mL-1 hr-1 ind-1) which enables broad-scale comparisons across an array of taxa and studies. To evaluate the accuracy and feasibility of our approach, we use the zooplankton, Daphnia dentifera, as a case study. Our results indicate that this procedure accurately quantifies feeding rates and highlights differences among seven genotypes. The method detailed here has broad applicability to a diverse array of aquatic taxa, their resources, environmental contaminants (e.g., plastics), and infectious agents. We discuss simple extensions to quantify epidemiologically relevant traits, such as pathogen exposure and transmission rates, for infectious agents with oral or trophic transmission.

Original languageEnglish (US)
Pages (from-to)6239-6245
Number of pages7
JournalEcology and Evolution
Volume10
Issue number13
DOIs
StatePublished - Jul 1 2020

Keywords

  • Daphnia
  • High-throughput
  • aquatic herbivore
  • consumer–resource
  • environmental contaminants
  • exposure rates
  • feeding rates
  • ingestion rates
  • predator–prey
  • transmission

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Ecology
  • Nature and Landscape Conservation

Fingerprint Dive into the research topics of 'A high-throughput method to quantify feeding rates in aquatic organisms: A case study with Daphnia'. Together they form a unique fingerprint.

  • Cite this