Laboratory Evaluation of Commercial Insecticidal Baits Against Oriental Cockroaches (Blatta orientalis L.) From Pig Farms in Bulgaria

Background: The oriental cockroach (Blatta orientalis L.) is a common pest in livestock farms, posing a risk as a mechanical vector for pathogens. Objectives: This study aimed to evaluate the insecticidal efficacy of four commercially available food baits against B. orientalis collected from seven industrial pig farms in Bulgaria. Methods: A no-choice bait feeding test was conducted under controlled laboratory conditions. Baits tested included indoxacarb gel, imidacloprid + S-methoprene gel, and two inorganic desiccant-based formulations.Results: Indoxacarb gel exhibited a rapid knockdown effect, reaching 100% immobilization by 96 h. The imidacloprid + S-methoprene gel induced early knockdown (66.7% by 48 h) and progressive mortality, achieving 96.7% by 168 h. The inorganic desiccant-based baits did not induce pronounced knockdown (<25%) but also resulted in complete mortality by the end of the test (168 h), although with delayed dynamics. Conclusion: The results highlight the practical value of insecticidal baits as an effective and safer component of integrated pest management programs in livestock production systems, adaptable to diverse conditions and infestation levels, with product selection depending on cockroach density and the desired speed of action.