The Commerce Commission has confirmed it is investigating a complaint against stock and station companies for imposing a new fee at sale yards.
The investigation relates to the national animal identification and traceability scheme (NAIT) introduced for cattle earlier this year. It requires farmers to attach new radio frequency ear tags to cattle and, from next year, to deer as well.
A complaint has been laid by Northland farmer Hugh Rose, a strong critic of the NAIT system.
Mr Rose alleges that stock and station firms have colluded in agreeing to a standard administration fee to cover data collection for NAIT.
He says the 75 cent fee is being imposed on both buyers and sellers of cattle making a total charge of $1.50 a head.
The Stock and Station Agents Association says the extra fee on cattle bought and sold in sale yards is justified, and stock firms have been upfront about it.
The Commerce Commission says it's at the early stage of its investigation.
Meanwhile, Mr Rose is urging farmers who run into difficulties with the NAIT system to inform the company running it.
He says up to 40 farmers turned up at meeting he called in Dargaville on Tuesday and outlined issues including an increasing number of people being injured trying to attach the new ear tags to adult cattle.