Leo Salkin, 80, a writer and animator who worked with such pioneers as Walt Disney, Walter Lantz and Tex Avery. His first film credits were with Lantz on the "Oswald the Rabbit" cartoon series in the early 1930s. He was a Disney animator and continuity writer until 1942, when he went to work at Screen-Gems and then at MGM with Avery's crew. After wartime Navy service he returned to work for Disney, went to New York for Paul Winchell's show during the early days of TV and then again was with Disney for "Lady and the Tramp." In 1974 he directed and animated "The 2,000-Year-Old Man," the CBS TV film based on the Mel Brooks character. On Wednesday in Burbank of congestive heart failure.