Here's why:
* Onions and Garlic: Many vinaigrettes contain onions and garlic, which are toxic to dogs. Even small amounts can cause gastrointestinal upset, anemia, and other health problems.
* Vinegar: While vinegar itself isn't inherently toxic, it can cause stomach upset in dogs, especially if they're not used to it.
* Salt: Some vinaigrettes are high in salt, which can be harmful to dogs in large amounts.
Instead of vinaigrette, you can offer your dog plain, cooked chicken.
If you want to make your dog's chicken more flavorful, you can add a small amount of plain, cooked sweet potato or other safe vegetables. However, always consult with your veterinarian before making any significant dietary changes for your dog.