The fall out from the Midsummer Sun cobalt case continued on Thursday with stewards issuing a further 52 charges against six people, including trainer Sam Kavanagh.

Kavanagh was already facing eight charges after Midsummer Sun tested positive to cobalt and caffeine in pre-race tests prior to his Gosford Cup win in January.

He has been issued with another 16 alleged offences, including the race day treatment of a further five horses from his stable, among them four-time city winner Centre Pivot.

Flemington Equine Clinic veterinarian Dr Tom Brennan has been asked to answer 11 charges including the supply of two bottles of a substance labelled `Vitamin Complex' which contained cobalt.

Stewards also allege Brennan had knowledge that Midsummer Sun was treated with cobalt prior to winning the Gosford Cup.

Brennan now faces hearings in two states after being charged by Racing Victoria stewards last month in relation to high cobalt levels found in horses trained by Kavanagh's father Mark, and Danny O'Brien.

Aaron Corby, practice manager at Flemington Equine, stablehand Michael O'Loughlin, disqualified harness racing trainer Mitchell Butterfield and fellow harness racing identity John Camilleri have also been charged by Racing NSW stewards in relation to the Midsummer Sun case.

Camilleri is alleged to have sold and supplied race day drenches to Kavanagh while the charges against Butterfield include the administration of a drench to Midsummer Sun on Gosford Cup day.

Four days have been set aside to hear the charges against all six people, starting on July 20.

Kavanagh has been stood down from training since the results of Midsummer Sun's positive drug test came to light.

Meanwhile, trainer David Vandyke will front stewards on Monday after Queen Tara tested positive to the bronchodilator Ipratropium following her second placing at Gosford on April 30.