which channel did the broadcast?
NBC.
Space Seed
"Space Seed" was first broadcast in the United States on February 16, 1967, on NBC. 
what is space seed? The twenty-second episode of the of the American science fiction television series who were the actors? Ricardo Montalbán, Madlyn Rhue, Blaisdell Makee who directed it? Marc Daniels
wiki:19107142
Space Seed [SEP] Broadcast
"Space Seed" was first broadcast in the United States on February 16, 1967, on NBC. A 12-city overnight Trendex report compiled by Nielsen ratings showed that during the first half-hour, it held second place in the ratings behind "Bewitched" on ABC with 13.12 million viewers compared to "Bewitched"s 14.44 million. The episode beat "My Three Sons" on CBS. During the second half-hour it was pushed into third place in the ratings by the start of the Thursday Night Movie on CBS, the Western film "One-Eyed Jacks" starring Marlon Brando, which received 35.5 percent of the audience share compared to 28 percent for "Space Seed".