Here's why:
* Spoiled food can contain bacteria: Spoiled greens can harbor harmful bacteria like Salmonella and E. coli that can cause food poisoning in dogs, leading to vomiting, diarrhea, lethargy, and even more serious complications.
* Toxicity: Spoiled greens can produce toxins that can be harmful to dogs.
* Upset stomach: Even if the greens are not seriously spoiled, they can still cause an upset stomach in dogs, leading to vomiting or diarrhea.
It's always best to err on the side of caution and avoid giving your dog spoiled food. Instead, offer fresh, healthy treats and food. If you are unsure about a food item, it's always best to consult with your veterinarian.