Facteurs favorisant l’apparition de la maladie de Newcastle au Tchad

Abstract

Objective: Each year, Newcastle disease (ND) occurs spontaneously in rural households from October to May. This gives it a seasonal nature. Knowledge of the causes and factors of seasonality of the occurrence of Newcastle disease is an asset for its prevention. Methodology and Results: Annual reports and studies undertaken between 1990 and 2006 have been a basic of documentation. In addition, in 2007 a survey has been conducted in nine (9) cities and their peripheries. The choice of households has been randomly selected and subject to availability of producers. Elaborated survey forms focused on information related to climate, mortality of chickens, period of onset of ND, age of affected birds and livestock practice. Collected data has been analyzed using the software tool "Excel.” The average of monthly temperature varied between 24 and 34 ° C, The occurrence of ND has been seasonal with three periods in the year: two periods of outbreaks (November-February) and (March -June) and a period of lull (JulyOctober). Conclusion and application: The season, livestock density and human behavior are factors favoring the occurrence of ND in Chad. The seasonality of ND is closely related to the high density of chickens (restocking of