This manual does not pretend to be a comprehensive treatise on management
of livestock wastes -- which would be an impossible task given the diversity
of economic, social and ecological factors that typify farming systems
in different regions of the world. In fact, a "manual" by definition
is a practical guide to the installation, management and maintenance of
a particular technology. It follows that the authors of such manuals
should be experienced practitioners of the "art" that they propose to demonstrate
and explain to potential adopters of the technology. The authors of the
present manual have been living and working with productive recycling of
livestock wastes for the past five years in Vietnam and, in the case of
one of us (TRP), researching elements of the technology for twenty years.
The manual is based on the personal experiences of the authors and relates
specifically to ecosystems in the humid tropics. Even in these ecosystems
there are many approaches that can be followed and the recommendations
that are made in no way preclude the other alternatives.
TR Preston and Lylian Rodríguez