Abstract:
Newcastle disease (ND) is a serious infectious disease of the poultry caused by virulent
strains of Avian Paramyxovirus-1 and has greatest impact on villages where people’s
livelihood depends upon poultry farming in several developing countries including Ethiopia.
Thus, the aim of the present study was to estimate individual and household flock level
seroprevalence and associated risk factors of ND in unvaccinated backyard chickens in
Damo Gale and Kindo Koisha districts, Wolaita zone, southern Ethiopia. A cross-sectional
study design coupled with semi-structured questionnaire was conducted. For the study, the
household flocks were sampled as a cluster, then the required number of household flocks
selected randomly; and all backyard chickens within the household flocks with age of greater
than 3 months were sampled. A total of 1017 blood samples were collected from 164
household flocks during the study period. None of chickens enrolled in the study were
vaccinated against ND. Serum samples were tested for ND antibodies using an Indirect Enzyme Linked Immuno Sorbent Assay. The overall seroprevalence of Newcastle disease
virus (NDV) at individual and flock level was 24.2% (95% CI: 21.7-26.9%) and 64.6% (95%
CI: 57.0-71.6%), respectively. A multivarible logistic regression analysis was applied to
assess ND seropositivity and the associated risk factors at individual and flock level. The
odds of ND sero-positivity was significantly higher in backyard chickens belonging to Damot
Gale district in comparison to Kindo Koysha with an odds ratio of 2.4 (95% CI:1.76-3.19; p
< 0.001). The odds of ND seropositivity of crossbreed chickens was significantly higher
compared with local breeds with an odds ratio of 2.15 (95% CI: 1.54-3.00; p<0.001). The
potential household flock level risk factors associated with ND seropositivity in this study
were flock size, chicken house cleaning frequency, water source for chickens, dead chicken
disposal practice, distance to the next neighbor household, mixing with wild birds and
owning pets. In conclusion, the current study generates important information on the
serporevalence and the potential risk factors associated with ND at individual and flock level
in Damot Gale and Kindo Koisha districts of Wolaita zone. Thus, routine ND vaccination
campaign should be launched and raising awareness about the disease through effecve extension programs should be provided
