Ant and Duck was short-lived sketch with "Farmer Ant" presenting a pseudo-preschool show teaching children about the countryside and Dec as the aggressively misanthropic Duck.
The sketch would feature a song where Dec would twist the lyrics to lambast the countryside and eventually, be forced by Ant into line with singing threats of calling the Chinese takeaway. Much of the humour came from Dec's attempts to twist the lessons about the countryside; for example, when Ant was talking about (in examples of people living in the country) the aristocrat who owned an estate, Dec replied Big Tony runs the estate! (meaning a council estate).
Duck was done by having Dec sitting on a stool in a duck costume, with fake duck legs on a haystack so it would look like Duck was short and sitting on the hayst