Neporex fly repellent 5 kg Neporex is an agent that prevents the fly larvae from developing into adult flies. Can be used in pig and cowsheds, poultry houses, as well as to control larvae of the small housefly on mink farms. Neporex has been specifically developed for fly larvae and is therefore not toxic to the fly's natural enemies. Dosage: It can be used in barns with bedding in manure, in poultry houses, and other places where the fly larvae live. Generally, 2 treatments 14 days apart are sufficient to effectively stop the production of flies. 500 grams is enough for approx. 20 m².