Santa's Little Helper prompted satires of contemporary dog culture, from Barbara Woodhouse's authoritarian training methods [in "Bart's Dog Gets an F"] to Lassie's flawless service to the status quo [in "The Canine Mutiny"]." Although cast member Dan Castellaneta occasionally voiced Santa's Little Helper for bit parts, American voice artist Frank Welker most often provided the sounds of the dog and other animals on the show from "Bart's Dog Gets an F", which aired on March 7, 1991, to "Home Sweet Homediddly-Dum-Doodily", which aired on October 1, 1995. He said on his official website in 2007 that he liked portraying Santa's Little Helper because
Helper dependent virus and capsid encoding DNA, plus helper DNA. Every cell that is successfully transfected with all three DNA fragments will produce the necessary proteins to produce infective viruses. These viruses will only have transgenic DNA encapsidated and therefore once they've infected a patient's cell, they will not be capable of reproducing. Helper dependent viruses can also occur in nature without being "gutted". The term satellite virus has been given to a large group of viruses that all require the presence of another virus to replicate. Many of these are plant viruses, but animal viruses can be seen in the case of