Efficacy and safety of Diazinon and botanical extracts (Tephrosia vogelii, Cissus quadrangularis) for flea control in chickens: a factorial study under Ethiopian conditions

The limited availability and high cost of synthetic insecticides necessitate the exploration of effective and safe botanical alternatives for ectoparasites control in poultry. This study compared the efficacy and adverse effect profiles of a synthetic acaricide (Diazinon) and two indigenous plant extracts, Tephrosia vogelii and Cissus quadrangularis for flea eradication in chickens. A 3 × 2 factorial experiment in a Completely Randomized Design (CRD) was conducted from April to December 2023. Factors included treatment (three levels: Diazinon, T. vogelii, and C. quadrangularis) and chicken breed (two levels: exotic and local). Each of the six treatment-breed combinations was replicated six times using pens of 10 chickens, totaling 360 chickens sourced from the Burji district. The protocol was approved by the appropriate institution (Ref No. 16.28/2023). Flea load, onset of action, and adverse reactions were meticulously monitored during the trial, and the collected data were entered into Microsoft Excel 2010 and analyzed using SPSS software, version 20. Results indicated a significant difference among treatments (p < 0.001) in eradicating fleas from chickens within 48 h. Diazinon and T. vogelii demonstrated a faster onset of action (mean differences = 6.62 and 12, respectively) compared to C. quadrangularis. Diazinon showed the most severe adverse effects, including blistering, swelling, and diarrhea, occurring in 15% of local and 23.33% of exotic chickens. Exotic breeds showed heightened sensitivity, with a significant treatment-by-breed interaction observed. C. quadrangularis caused moderate irritation (6.7% local, 11.7% exotic) of lower severity and shorter duration (1–2 days) than Diazinon, while T. vogelii showed the minimal adverse effects (1.7% local, 8.3% exotic), limited to transient mild redness with no systemic symptoms. While both botanicals show promise as effective and safer alternatives to synthetic chemicals. The cost-effectiveness analysis showed that Tephrosia vogelii and Cissus quadrangularis are about 88% cheaper ($7 vs. $60) than Diazinon, offering a highly cost-effective, community-based alternative. This finding advocates for the integration of T. vogelii into integrated pest management programs and underscore the critical importance of considering breed susceptibility in treatment protocols. Future research should focus on identifying the active compounds and establishing standardized dosages.