Sampling technique and Sample Size determination
Multistage sampling technique was employed to select study population by taking ‘district’ as the first stage, ‘pastoral association’ as the second stage, and ‘herd’ as the third stage. Study districts were purposively selected based on higher study population, access to transportation, history of outbreaks and willingness of pastoralists to participate in this research work for seroprevalence determination and assessment of potential risk factors of FMDV. Finally, individual animal from each herd was selected randomly as secondary sampling unit to attain the required sample size. Since there is no previous study conducted on FMD in cattle found in the selected areas, the present study has considered 50% expected prevalence, 95% confidence level and 5% absolute precision or marginal error. Based on these assumptions, the total number of animals to be included in the study got determined using Thrusfield (2007) formula.