Here is a description of the game from Spielbox:
The "Fette Kuhe" (Fat Cows) from Stuttgart-based Spielteufel first graced the gaming table in the 1990's. But they've been dead - excuse me, sold old - for a long time. But now, Fette Kuhe 2 is being released!
It's been nine years since a pair of farmers sat down at their favourite table in the local bar and started arguing about who had the fattest cows in the village - naturally, each claimed that honour for himself. In order to finally have peace in the bar again, the bartender made the following suggestion:
Pick a meadow and then have each farmer send a cow-herder along with 4 similar cows there. After no more than 18 days, the decision would be reached as to which farmer had the fattest cows - that farmer would be rewarded with a feast.
Nowadays, the argument has become a tradition and so the player take on the roles of the cow-herders that lead their cows to eat on the meadow. And also bring them lightning-quick into safety, making sure that they don't get sick in the windy and rainy weather. It's logical that the cows will eat as many grass tiles as they can get, since that's the only way that they'll get really fat.