An estimated 8000 European farmers protested in Prague on Thursday to demand higher milk prices and subsidies to boost their incomes.
Farmers from Germany, Austria, Slovakia, Slovenia and Poland marched through the capital. The Czech Republic currently holds the EU presidency.
A similar demonstration was held in the Bulgarian capital, Sofia, on Wednesday.
Milk and manure were dumped at the Agriculture Ministry.
The Czech Agriculture Chamber said milk prices were at their lowest since the Czechs joined the EU in 2004, and small farms are at risk.
Farmers said they wanted 40 euro cents as a minimum price for a litre of milk, double the market price of 20euro cents.
They want direct subsidies to dairy farmers or more buyouts from the EU, which the bloc can do to raise demand and keep up prices.