D.A.C.H.S.Haund 1

 was a comic book about a bionic dog that Izzy Sinclair once likened to The Six Million Dollar Man. She said the acronym stood for "Dog Activated by Complex Hyper Sircuitry". When the Eighth Doctor noted that circuitry had to be spelled with an s for the acronym to work, she admitted that "it was a bit poor". (BFA: Izzy's Story)

Behind the scenes
It's a bit unclear from the dialogue of Izzy's Story whether Izzy is talking about issue 1 of D.A.C.H.S.Haund, or whether the name of the comic includes the number 1. Since she seems to be talking about a general condition of the dog, however, we've elected to believe that 1 is a part of the title.