Flax seeds can be fed whole. We feed 1/4 cup every feeding and have beautiful healthy coats. Flaxseed is high in Omega 3 which aids in degestion, helps immune system and improves digestion. It can also be ground up prior to feeding but it looses its nutrients very fast once ground (like 20 minutes) so we feed it whole.
People who boil or soak their flax seed often do so because they believe that otherwise the flax might contain harmful levels of cyanide, which is toxic. In truth, while the seeds do contain the two components necessary to create cyanide, they are in different parts of the seed. Ironically, it’s the contact with water that brings the two components together and causes the formation of cyanide. Soaking is actually the most dangerous way to feed flax.
Hope this helps.