Many are still open to the public and cannot restrict access in "any meaningful way", the Australian Livestock Saleyards Association has told a state parliament inquiry into the impact of animal rights activism on agriculture.

The group, which represents livestock saleyards including at Bendigo, Echuca, Wycheproof and Kyneton, believes most council yards would have difficulty controlling people's movements.

"They are classified as public sites whereas a number of the privately operated saleyards are classified as private ... which brings into play different trespass rules, a submission to the inquiry from ALSA chairman Stuart McLean stated.

A number of salesyards have dealt with animal activists in recent years, his submission stated.

"Most of these interactions have been relatively easy to manage for our members to date," Mr McLean wrote.

Activists had largely been prepared to operate within saleyards' welfare rules and not disrupted activities like selling and moving stock.

While site inductions could potentially help, "that would not prevent activists accessing the site as .... (it) could not be denied to those parties in a public site", Mr McLean wrote.

Current legal arrangements would not be enough if there was an incident, he wrote, noting that saleyards have become key links for those tracing stock.

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The ALSA wants new rules for those trespassing and for tougher local bylaws.

It also wants courts to hand activists "adequate penalties" if charged with saleyard disruption offences.

Some members of the association have worked with groups like the police and Agriculture Victoria on plans in case of a serious incident, and to lower risks including to animal welfare.

Yet if there is a serious incident, the roles of police, the RSPCA and Agriculture Victoria are not clearly defined, Mr McLean wrote.

"Given this lack of coordination it is likely that a serous incident within saleyards ... (like) interfering with the sales process, would not be managed effectively as possible," he wrote.

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