Food preference of the German cockroach, Blattella germanica (L.) (Dictyoptera: Blattellidae)

Abstract

The German cockroach, Blattella germanica (L.), is a common indoor pest in low-income housing. Cockroaches not only spoil food but also transfer pathogens and cause allergic reactions and psychological distress. The 72 h-starved cockroaches were given choices among eight food items: four carbohydrate–rich foods (bread, biscuit, banana, and potato) and four protein-rich foods (minced meat, cooked cheese, white cheese, and luncheon). Modified fourchamber arenas were used for this food preference experiment. Each kind of food was placed in each chamber of the arena with 20 of starving cockroaches placed at the center. This experiment was done three times, one with the four carbohydrate–rich foods, the other with the four protein-rich foods, and the last with the preferred food from carbohydrate and protein. Another food preference experiment was conducted in the different modified four chamber arenas to determine the food consumption as the Rodgers’s index. The two arenas were observed after 3 days in the laboratory, the first one to estimate percent of attracted adults to different food items, while the second one to calculate the food consumption by using Rodgers’s index. The percentage of adults attracted to carbohydrate foods (biscuit and banana) and protein food (cooked cheese) was significantly higher than (bread and potato) and (luncheon, minced meat and white cheese) at p ≤ 0.05 in both type of food, respectively. Data showed that banana was high attracted to cockroach and gave significant difference between cooked cheese and luncheon and the lowest attracted was seen in biscuit when adults exposed to carbohydrate and protein food items in the same choice arenas. Data showed significance level of variation in food consumption (mg) by German cockroach adults were analyzed with ANOVA, Tukey’s P≤0.05. Data showed that biscuit was avoided food, whereas banana was preferred food item.