While some veterinarians may be against homemade food, it's not necessarily a universal stance. Some veterinarians may be against homemade food for puppies because preparing a balanced and complete diet for a puppy can be difficult, and it requires knowledge of canine nutrition, meal planning, and proper food handling. Puppies have different nutritional needs than adult dogs, and they require a specific balance of nutrients, such as protein, fat, and calcium, that are vital for proper growth and development. Vets are often concerned that homemade diets may not provide the right balance of nutrients that a puppy needs and can lead to nutritional deficiencies and health issues.