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My 12 kg dog ate a few florets of broccoli that were slimy and left in the fridge for two weeks — is the mold or spoilage the bigger risk?

Dogs · Food safety

Last reviewed: 2026-09-05 · Reference ranges: ASPCA, Pet Poison Helpline & Merck Veterinary Manual

Short answer

The spoilage bacteria and mold are the main risks, not the broccoli itself. Slimy broccoli can harbor bacteria that cause vomiting and diarrhea, usually within 6–12 hours. Mold can produce mycotoxins, which might cause tremors in large amounts, but a few florets likely won't reach that level for a 12 kg dog. Watch for stomach upset: loss of appetite, gurgling belly, or loose stools. Offer plain, fresh water and a bland meal like boiled chicken and rice if he seems hungry later. Call your vet if vomiting starts or if he becomes lethargic.

Broccoli — Food safety facts

Feed with care · Dogs · full breakdown on the linked food page

Safe in small pieces (steamed is gentlest). Stems in bulk can cause gas; the florets contain isothiocyanates that can upset the stomach in large amounts.

Dogs and cats carry the same rating (Feed with care), so the notes below hold for either pet.

Broccoli is not poisonous to dogs, but it is easy to over-feed. Rich fat, salt or seasoning can bring on vomiting or diarrhoea within a day, and repeated large portions are a recognised trigger for pancreatitis.

If it ate some before you noticed, watch for vomiting, diarrhoea, loss of appetite, unusual tiredness or a painful, swollen abdomen over the next 24 hours. A one-off small amount in a healthy adult usually passes with water and rest; repeated exposure, a puppy or kitten, a senior, or a pet with an ongoing illness is a reason to call your vet the same day.

Why these cautions matter

Caffeine overstimulates the heart and nervous system, and pets clear it so slowly that tremors and restlessness drag on far longer than they would in a person.

Broccoli can turn up now and then, but not as a daily habit: keep the rest of the day's food unchanged and watch the next walk and the stool that comes with it.

The full verdict, portion guidance and serving notes are collected on the Broccoli food facts page.

Open the full food page: Broccoli food facts →