Paraguay is a South-American country member of the Mercosur block. It has an area of 406,752 Km2, limiting with Argentina, Bolivia and Brazil. It is watered by 2 mighty confluent rivers, Paraguay and Parana that conform with their tributaries one of the most important hidric systems in America. The main domestic productive activity is the agriculture and cattle raising. More than 25,500,000 hectares are affected and cattle production almost 50% corersponds to natural pastures, and the other portion to natural forest, cultivates pastures and rivers courses. In these areas, natural (wild) on most part, more than 11,000,000 of the best meat-producing of bovine livestock are raised.