[Triatoma brasiliensis Neiva, 1911 (Hemiptera, Reduviidae): observations on dynamics of feeding behavior in an artificial ecotope]

In order to study the behavior of triatomine bugs under artificial ecotopic conditions, an experimental, double-walled poultry coop was built. Its inside walls were made of sun-dried clay blocks which could be broken apart for better access to the insects hiding in their crevices. The coop was subdivided into two main areas of different sizes using wire netting and a wall made of perforated bricks. The chickens, the only food source available for the triatomines, were kept in the larger, rectangular area, further subdivided diagonally. The triatomines were released in the smaller area and were allowed to migrate to the larger one though the holes in the bricks. Information about migration, survival, and hiding places of fourth-stage nymphs of Triatoma brasiliensis was thus gathered. At 30-day intervals, over a period of six months, the inner walls of the house were taken apart and inspected. The nymphs were marked with different colors according to the month and place of capture. It was found that 88.5% of the nymphs were captured near the roost and found engorged. After having taken their first blood meal, they would remain in the vicinity of their food source. The results obtained are considered epidemiologically relevant, and particularly so as pertaining to the control of the vectors of Chagas disease.