Egg microinjections – method experimental viral infections in brook trout Salvelinus fontinalis (Mitchill, 1815) and rainbow brook trout Salvelinus fontinalis ♂ × Oncorhynchus mykiss ♀

Microinjection is a micromanipulation technique that has been used in various fields and in a variety of species, including teleost fish, for over a hundred years. Microinjection is mainly used in genetic, molecular, and toxicological research. The paper describes an experimental study of a microinjection technique for the administration of Infectious Pancreatic Necrosis Virus (IPNV) in fertilized eggs of brook trout, Salvelinus fontinalis (Mitchill), and a rainbow trout Oncorhynchus mykiss (Walbaum) hybrid, Salvelinus fontinalis ♂ × Oncorhynchus mykiss ♀. The oocytes and embryos of these salmonids have complex structures that require modifying the method commonly used in zebrafish, Danio rerio (Hamilton), research. A modular apparatus and technique for injecting brook trout and rainbow brook trout fish embryos with IPNV are described. The modified microinjection method can be used successfully to administer to salmonid eggs infectious substances that simulate the vertical transmission of pathogens.