The barkoo knotted bones with spirulina are a healthy natural dog chew treat your dog to something different with tasty chew made from natural beef rawhide with spirulina it lasts for ages and helps your dogs dental hygiene spirula is an algae which is packed full of valuable minerals trace elements vitamins proteins and amino acids barkoo knotted bones with spirulina are made without artificial colours preservatives and aroma they make a great snack and dogs cant get enough of them