All of my shepherds would leave food on a command. They had to be trained to do this to protect them to prevent poisoning etc because of their job in police work. They also would not eat until told to do so for the same reason. ..
The borzois- uhh hottie would and femka.. Zubin and Galina- alias the bottomless pits ( sorry the pun) - no WAY would they leave something to eat.. Zubin one day- I was soaking a pan used for frying- it was in the sink.. It had the smell to it of cooked grease- but also had Dawn in it- well he put his nose in the sink- and drank some of the water before I saw it- then spent the next 10 minutes throwing up.. I was like " see boy- that will teach you.. lol.." and yes- he was fine. I called the vet to make sure but he said as long as he was vomitiing and none of the ingredients would really hurt him. He now stays away from the kitchen sink although tall enough to drop his head into it.. loll ( puppies- jeez!)