The rapid decline of amphibian populations around the world is widely accepted in the scientific community. Many of these population declines are caused by a disease called chytrid, which is the result of a skin infection caused by the fungus Batrachochytrium (Bd). In this paper we determine the role of the mucosoma (mucosal antibodies, antimicrobial peptides, alkaloids and metabolites) of some species of the families Dendrobatidae and Aromabatidae on the fungus Bd. These families were chosen because it has been found that sometimes they are able to live with the fungus without affectation. four individuals from the following species were used: Rheobates palmatus, Dendrobates truncatus and histrionica Oophaga and preparing their mucosomas was performed by means of extraction and freeze drying of the skin. Same strain of the pathogenic fungus EV001 was reactivated and zoospores an inoculum was made. It was carried out mounting plates 96-well microtiter, which was incubated at 23 ° C and evaluated at 24, 48, 72 and 96 hours on a microplate reader; This allowed estimate the level of growth Bd. The optical density values ​​of a total of 42 samples in which it was found that the mucosoma is a possible source of nutrients for Bd analyzed, since in most cases this it grew by 40% compared to the culture medium tryptone 1% with zoospores. Of the three species was found that the extract of R. palmatus further accelerated growth Bd against those of D. truncatus and O. histrionica. In addition to this it was determined that there is no direct relationship between the weight of the individual's skin and the degree of damage that can eventually cause the mucosoma on chytrid