12 Mo. A retrospective method for estimating demographic parameters in tropical ruminant livestock population. Version 3.1

This document is intended for educational use and is a handbook to be used by researchers, engineers, and technicians of national services, development professionals or students who are dealing with demographic parameters (reproduction, mortality, etc.) of tropical livestock ruminant (cattle, small ruminants and camels). This handbook concerns the retrospective approach and is based on farmers' interviews and their medium- or long-term recall of the herd's demography. 12 mo focuses on livestock populations in traditional tropical farming systems that are non-intensive and where animal production is subject to little or no control. The handbook comprises six chapters. Chapter 1 describes the general protocol for a 12 mo survey; chapter 2 and 3 describes the survey questionnaires and a database interface for entering data collected, in the field. Chapters 4, 5 and 6 go in to the detail of calculating the demographic parameters and provide a numerical example.