[Ecopathological survey on pneumopathies in goats during the dry cold season in Chad: methodological aspects]

The authors describe the methodology used in an ecopathological survey of goat pneumopathies in periurban area of N'Djamena (Chad) during the dry, cold season of 1991-1992. The choice of farms was made after a typology survey. A total of 3,500 small ruminants (85% of goats) belonging to 60 farms were identified and the performance and health of the animals examined from August 1991. The protocol used for collecting information and the strategy applied to the analysis of data were based on conceptual pre-models of analysis corresponding to the 3 observations scales used, i.e. goat, concession flock, day flock. The survey took place from December 1991 to March 1992. The difficulties of the statistical interpretation of the data, are emphasized. The biological significance of the risk factors is discussed. Measures for obtaining improvements should take into account the cost/profit ratio and the technical and financial possibilities of the farmers.