There is a need for effective and environmentally sensitive methods of controlling vertebrate pest problems in agriculture and urban environment. Nonlethal natural repellents may meet this need where more traditional methods of control, such as scaring, shooting, and trapping, are either ineffectual or unacceptable. Neem (Azadirachta indica A Juss) extracts: oil, seed and leaf powder and chemicals from cockroach (Blaberus giganteus L.) were tested for their repellent properties. In addition defensive volatiles from B. giganteus were tested in an arena based on choice by smell (cheese or insect volatiles). This arena test used laboratory rats (Rattus norvegicus Berk.); females were more active than males. Both sexes visited the holes with cheese more than holes containing insect's volatiles. However in a feeding test with one choice of food the control did not differ from the treatment. Neem products seem to act as antifeedant on rats: neem seed oil, neem seed powder and neem leaf powder reduced rats feeding respectively at concentration of 15 ml of oil/kg, 15--50 g of seed powder/kg, and 25--50 g of leaf powder/kg of rat chow. Overall neem leaf powder was less effective than seed powder and oil. Neem and insect products may have potential in controlling rats particularly in storage situation, which could lead to an important reduction of post-harvest loss of grains in Sahelian and Asian countries.

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