title: Incubation at 32.5°C and above causes malformations in the zebrafish embryo.
abstract: Zebrafish embryos are increasingly used for developmental toxicity screening of candidate drugs and are occasionally co-incubated with a metabolic activation system at 32°C for 1, 2 or 4h, depending on their developmental stage. As this temperature is higher than the optimal temperature for zebrafish embryonic development (26-28.5°C), we investigated whether continuous incubation of zebrafish embryos from 2.5 until 96h post fertilization (hpf) at high temperatures (30.5-36.5°C) causes malformations. At 32.5°C tail malformations were observed as early as 24hpf, and these became even more prominent at 34.5 and 36.5°C. Cardiovascular and head malformations, edema and blood accumulations throughout the body were present at 36.5°C. Finally, temperatures higher than 28.5°C accelerated embryonic development except for 36.5°C, at which a lower hatching rate and hatching enzyme activity were observed. In conclusion, incubation of zebrafish embryos at 32.5°C and above from 2.5 until 96hpf causes malformations as early as 24hpf.
authors.affiliation: University of Antwerp, Applied Veterinary Morphology, Universiteitsplein 1, 2610 Wilrijk, Belgium.
authors.forename: Casper
authors.initials: C
authors.lastname: Pype
authors.affiliation: University of Antwerp, Applied Veterinary Morphology, Universiteitsplein 1, 2610 Wilrijk, Belgium.
authors.forename: Evy
authors.initials: E
authors.lastname: Verbueken
authors.affiliation: University of Antwerp, Applied Veterinary Morphology, Universiteitsplein 1, 2610 Wilrijk, Belgium.
authors.forename: Moayad A
authors.initials: MA
authors.lastname: Saad
authors.affiliation: University of Antwerp, Applied Veterinary Morphology, Universiteitsplein 1, 2610 Wilrijk, Belgium.
authors.forename: Christophe R
authors.initials: CR
authors.lastname: Casteleyn
authors.affiliation: University of Antwerp, Applied Veterinary Morphology, Universiteitsplein 1, 2610 Wilrijk, Belgium.
authors.forename: Chris J
authors.initials: CJ
authors.lastname: Van Ginneken
authors.affiliation: University of Antwerp, Veterinary Physiology and Biochemistry, Universiteitsplein 1, 2610 Wilrijk, Belgium.
authors.forename: Dries
authors.initials: D
authors.lastname: Knapen
authors.affiliation: University of Antwerp, Applied Veterinary Morphology, Universiteitsplein 1, 2610 Wilrijk, Belgium. Electronic address: steven.vancruchten@uantwerpen.be.
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Van Cruchten
mesh_terms: D000818:Animals; D001681:Biological Assay; D056668:Cathepsin L / Q000378:metabolism; D004625:Embryo, Nonmammalian / Q000002:abnormalities* / Q000201:enzymology; D013696:Temperature; D013997:Time Factors; D018675:Toxicity Tests / Q000379:methods*; D015027:Zebrafish / Q000002:abnormalities* / Q000378:metabolism; D029961:Zebrafish Proteins / Q000378:metabolism
chemical_list: D029961:Zebrafish Proteins; D056668:Cathepsin L
keywords: Development; Embryo; Hatching enzyme; Malformation; Morphology; Temperature; Zebrafish