The promotion of bestiality in "liberal" Judaism traces back to claims in orthodox Jewish writings such as

that before Eve existed Adam had "physical relations" with all the animals in orthodox Jewish writing

that if a Jew has relations with a gentile then they have not committed adultery but bestiality in orthodox Jewish writings

that Gentiles are non human animals created in human form to serve Jews in orthodox Jewish writings

that Gentiles are non human but Jews are permitted to...them