newsticker-ticker-interval

newsticker-ticker-interval is a variable defined in `newst-ticker.el'.
Its value is

0.3

Documentation:
Time interval for displaying news items in the echo area (seconds).
If equal or less than 0 no messages are shown in the echo area. For
smooth display (see `newsticker-scroll-smoothly') a value of 0.3 seems
reasonable. For non-smooth display a value of 10 is a good starting
point.

You can customize this variable.