title: Automated zebrafish chorion removal and single embryo placement: optimizing throughput of zebrafish developmental toxicity screens.
abstract: The potential of the developing zebrafish model for toxicology and drug discovery is limited by inefficient approaches to manipulating and chemically exposing zebrafish embryos-namely, manual placement of embryos into 96- or 384-well plates and exposure of embryos while still in the chorion, a barrier of poorly characterized permeability enclosing the developing embryo. We report the automated dechorionation of 1600 embryos at once at 4 h postfertilization (hpf) and placement of the dechorionated embryos into 96-well plates for exposure by 6 hpf. The process removed ≥95% of the embryos from their chorions with 2% embryo mortality by 24 hpf, and 2% of the embryos malformed at 120 hpf. The robotic embryo placement allocated 6-hpf embryos to 94.7% ± 4.2% of the wells in multiple 96-well trials. The rate of embryo mortality was 2.8% (43 of 1536) from robotic handling, the rate of missed wells was 1.2% (18 of 1536), and the frequency of multipicks was <0.1%. Embryo malformations observed at 24 hpf occurred nearly twice as frequently from robotic handling (16 of 864; 1.9%) as from manual pipetting (9 of 864; 1%). There was no statistical difference between the success of performing the embryo placement robotically or manually.
authors.affiliation: Oregon State University, Corvallis, OR, USA.
authors.forename: David
authors.initials: D
authors.lastname: Mandrell
authors.forename: Lisa
authors.initials: L
authors.lastname: Truong
authors.forename: Caleb
authors.initials: C
authors.lastname: Jephson
authors.forename: Mushfiqur R
authors.initials: MR
authors.lastname: Sarker
authors.forename: Aaron
authors.initials: A
authors.lastname: Moore
authors.forename: Christopher
authors.initials: C
authors.lastname: Lang
authors.forename: Michael T
authors.initials: MT
authors.lastname: Simonich
authors.forename: Robert L
authors.initials: RL
authors.lastname: Tanguay
mesh_terms: D000818:Animals; D057205:Automation, Laboratory; D002823:Chorion / Q000378:metabolism*; D055808:Drug Discovery; D004353:Drug Evaluation, Preclinical / Q000295:instrumentation / Q000379:methods; D047108:Embryonic Development / Q000187:drug effects; D057166:High-Throughput Screening Assays; D012371:Robotics / Q000639:trends; D056826:Single Embryo Transfer / Q000295:instrumentation* / Q000379:methods; D018675:Toxicity Tests; D015027:Zebrafish