Yes, because Samurott has to be a female if you want to get Oshawott. You are only getting Farfetch'd because the parent is female. If you want to get Oshawott with Air Slash see If one of your Farfetch'ds is that you got from the eggs are male, then breed it with a Female Oshawott, Dewott, or Samurott. You can breed your Samurott with a Ditto to get a Oshawott again.
Look at this for help: http://pokemondb.net/mechanics/breeding