In general, Ceramic or metal food dishes bowl is the best choice for breeding. Plastic bowl is more easily to get scratches which is a good place to generate and attach baterias and other pathogens. This increases the chance for your dog to get sick. And these scratches are harder to clean than you think, even regular cleaning and disinfection will not guarantee your dog’s health. So the ideal material for dogs’ dishes is food grade ceramic or metal(stainless steel is the best).