Liberal senator David Van has owned up to interjecting against independent Jacqui Lambie when she was asking a question, but denied he growled or made dog noises.
Labor senator Penny Wong sought to have the remarks withdrawn at the time but no senator claimed responsibility for the noise.
"Gee you're tough aren't you? You're happy to dish it out, but not happy to take responsibility," she said.
"At least 'fess up."
Senator Van later came back to the chamber and owned up but rejected the characterisation of his interjection, inferring he did not make any growling or dog noises.
"I reflected on my behaviour in question time and I acknowledge that interjections are always disorderly," he said.
"I also acknowledge I was making interjections when Senator Lambie was asking a question during question time.
"I commit to holding myself to the highest standards in the future."
Greens senator Sarah Hanson-Young said it was not appropriate for the noises to be made while a female member was on her feet, especially on the same day a damning review into the culture at Parliament House was released.
"If we are going to change culture from the top, that means all of us," she said.
Just hours before the incident, Sex Discrimination Commissioner Kate Jenkins' report into parliamentary culture detailed a leadership deficit, where disrespectful behaviour "comes from the top".
Leader of the Government in the Senate Simon Birmingham said the conduct was "unacceptable".
"There is a standard of conduct everyone (in parliament) should adhere to," he told the ABC.
Greens senator Larissa Waters called for a code of conduct to be implemented for senators but said parliamentarians shouldn't need a code to know not to act in such a manner while a woman was speaking in the chamber.
Australian Associated Press