If using a metal cage to transport dogs, ensure it has a roof to provide shade, and that the sides are well ventilated. 

It is also advisable to cover metal floors of cages, and if tethering, the tray floor, with a surface such as rubber, as metal can heat up quickly. In addition, ensure the cage is the right size to prevent cramping and overcrowding.

When stationary, the vehicle should be parked in the shade and the dog should always be left with water.

Victoria’s Prevention of Cruelty to Animals Act requires dogs travelling in the back of utilities, trailers or open tray trucks to be tethered or caged in a manner that prevents them from falling from the vehicle, the only exemption being when dogs are actively moving stock.

The tether should be only long enough to permit the dog to stand, lie down and move about but not so long in length that it could potentially let the dog fall off the vehicle. Tethering dogs should always be regarded as a short-term method of restraint.

For further advice contact the RSPCA, your local or DEDJTR Veterinary or Animal Health Officer, or in NSW your Local Land Services.  You can also find information on caring for all animals during hot conditions at http://agriculture.vic.gov.au/agriculture/animal-health-and-welfare.