This work integrates toxicological, ecological, clinical and veterinarian aspects to diagnose main causes deathly affecting cattle in livestock areas of Chaco Húmedo, Tarija, Bolivia, producing annual losses of about 2 millions of dollars, obtaining, in a short period of time, novel results to improve the characterization of toxic process in bovine herds, while warnning about the risk which human settlements were exposed to, through food chain and the compsumption of milk and meat from intixicated animals, which represented an important aspect for the Public Health.

This research is the first study undertaken in this far away Bolivian region, with a comprehensive range of the problem, developing a methodology elaborated by the Cuban team. The toxical and epidemiological survey evidenced a rising hematuria picture , with an incidence rate between 7.8% and 10.6% in 6 zones of 3 provinces as well as the presence of another fatal clinical picture, with the oropharynxy obstruction and impediment for feeding and ruminating. The clinical study evidenced anemia and leucopenia in 100% of cases. The botanic study showed contamination levels of Pteridium aquilium of 50 % in pasturelands and the presence of two varieties. The phytochemical study, MPLC, in toxic plant, pointed out the presence of “Ptaquiloside” norsesquiternum in concentrations which justify the process severity.

The food availability analysis showed an overpasture effect, which have contributed to P. Aquiliumm spread and some other weeds. It coul be possible to identify associated factors as the casue of this toxicosis such as the ones dependent on toxic plants, animal associated, man dependent and environment dependent.

This work is supported by a publication in Veterinary Human Toxicology and by its presentation in the 6th International Symposium of Poisonous Plants held in Scotland, as well as its acceptance in Animal Health Journal. It was also presented in the 1st Workshop of Plant Toxics and in the 17th Congress of Veterinarian Sciences held in Panama.