The foods that dogs consume, including vegetables, play a huge role in their health and how long they live. But while some vegetables can improve a dog's health, others contain chemicals that are harmful to canines and can cause minor digestive problems, severe illness or possibly even death. The American Society for the Prevention of Cruelty to Animals (ASPCA) reports that various human foods, some vegetables among them, made the list as one of the top 10 pet poisons in 2009.
The soluble calcium oxalates in rhubarb leaves make this vegetable one of the most dangerous plants for a dog to consume. The chemical can affect a dog's nervous, digestive and urinary systems, and can result in excessive drooling, tremors and kidney failure, according to the Garden Guides website. If these symptoms are not treated quickly, it could cause the dog's death.
Avocado leaves, fruit, seeds and even tree bark contain persin, a chemical that makes dogs suffer from diarrhoea and vomiting. If these symptoms continue, the dog could experience dehydration, according to Garden Guides.
Garlic contains N-propyl disulfide, a toxin that affects dogs in many ways. The side effects include a rapid heartbeat, excessive panting, lethargy and blood in the urine, according to Garden Guides. If a dog continues to consume the herb, the combination of N-propyl disulfide and thiosulphate, another chemical in garlic, can give the dog hemolytic anaemia, an illness that makes the red blood cells circulating in the bloodstream burst, leaving the dog with a low red blood cell count, according to PetInfo's website.
Onions, Chives and Shallots
Onions, chives and shallots also contain a relatively high amount of N-propyl disulfides, as well as sulfoxides, which together can damage red blood cells and cause gastrointestinal irritation, according to Garden Guides. This can occur whether the onions are raw, cooked or in powder form.
While some vegetables are deadly to dogs, there are safe vegetables that carry powerful antioxidants which can slow down a dog's rate of ageing and reduce the possibility of chronic disease. Appropriate vegetables for canines include broccoli, squash, carrots, green beans, cabbage and most other leafy vegetables, according to The Real Owner website. These vegetables also provide dogs with a good source of soluble fibre.