Animal welfare activists have launched an advertising campaign with images of sick and distressed ducks at NSW farms, targeting Sydney's Chinese community, who they claim is fuelling the demand for duck meat.

Animal Liberation wants to raise awareness that millions of the birds are suffering on Australian farms because they are routinely deprived of water to swim or bathe in, it says.

A row of glossy, freshly roasted ducks hanging by their necks in a restaurant.

"Water deprivation is one of the most severe welfare concerns within modern farming practices because ducks are designed for a life on water," campaign manager Emma Hurst said.

"It can lead to lameness, broken bones, breast blisters, loss of their centre of gravity, and skin damage from high ammonia concentrations."