The efficacy and residual efficacy of commercial baits, Quick Bayt® (0.5% w/w
imidacloprid) and Agita® (10.0% w/w thiamethoxam) against synanthropic flies were evaluated
under field conditions. Efficacy was evaluated based on knockdown percentage (KD %). The bait
efficacy and residual efficacy evaluation were conducted for a period of 3 weeks and 6 weeks
respectively. Baits were applied onto bait targets and placed on fly-count targets to facilitate the
counting of flies. All baits were applied according to the manufacturer’s recommended application
rate. Three replicate treatments for each type of bait were placed at the study site each week. The
number of flies feeding on baits and the knocked down flies were counted and collected. The
efficacy of Agita® and Quick Bayt® did not differ significantly (t-test, P>0.05) over the 3-week
period, even though Quick Bayt® had a slightly higher KD% than Agita®. In the residual efficacy
evaluation, the (knockdown) KD% of Quick Bayt® was consistent at around 36% for the first five
weeks but dropped to 33.8 ± 0.4% on the sixth week. The KD% for Agita® on the first week was
33.6 ± 12.2% and remained relatively consistent for the first 4 weeks at around 31%. KD% dropped
to 16.7 ± 3.3% on week 5 and to 15.7 ± 1.2% on week 6. The difference in residual efficacy of the
two baits was significant (t-test, p