https://www.google.co.uk/search?q=broccoli+as+it%27s+poisonous+to+dogs.&ie=utf-8&oe=utf-8&gws_rd=cr&ei=DLqOWdiaOqbJgAaEur7oCg 
  
Broccoli Is Safe in Small Amounts, But It Can Be Harmful. Unlike humans, dogs don't need large amounts of fruits and vegetables to live healthy lives. ... According to Dr. Klein, broccoli florets contain isothiocyanates, which can cause mild-to-potentially-severe gastric irritation in some dogs.15 Jul 2016
 
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