[Influence of the temperature and humidity on the biology of Rhodnius neglectus Lent, 1954, in laboratory conditions (Hemiptera, Reduviidae, Triatominae)]. / Influência da temperatura e umidade na biologia de Rhodnius neglectus Lent, 1954 em laboratório (Hemiptera, Reduviidae,Triatominae).

The objective of the present paper was to study the development of R. neglectus in the laboratory under different conditions of temperature and humidity. Three groups were prepared: 33/40 (33+/- 1 degree C and 40% +/-5% UR), 33/70 (33+/- 1 degree C and 70% +/-5% UR), and 28/70 (28+/- 1 degree C and 70% +/-5% UR). All these groups were observed daily to evaluate the eggs' incubation period, the development period of each instar nymph, the mortality rate of each stage, the frequency of feeding and the hatching - adult ecdysis period. The embryonic development showed significant differences between the treatment given, the group 33/40 presented the lowest incubation period. The lowest bloodmeals number was observed in the group 33/40 except for the first instar (group 28/70). The period of nymphal development was significantly reduced in the group 33/40, however, the mortality was high and the specimens did not reach the adult phase.

Influência da temperatura e umidade na biologia de Rhodnius neglectus Lent, 1954 em laboratório (Hemiptera, Reduviidae,Triatominae) / Influence of the temperature and humidity on the biology of Rhodnius neglectus Lent, 1954, in laboratory conditions (Hemiptera, Reduviidae, Triatominae)

O objetivo do presente trabalho foi observar o desenvolvimento de R. neglectus em diferentes condições de temperatura e umidade. Três grupos foram formados:33/40 (33+/- 1ºC e 40% +/-5% UR), 33/70 (33+/- 1ºC e 70% +/-5% UR), e 28/70 (28+/- 1ºC e 70% +/-5% UR). Todos os grupos foram observados diariamente para avaliação do período de incubação dos ovos, período de desenvolvimento dos estádios ninfais, percentual de mortalidade por estádio, número de repastos realizados, e período de desenvolvimento da eclosão a muda imaginal. O desenvolvimento embrionário apresentou diferenças significativas em todos os tratamentos, o grupo 33/40 apresentou o menor período de incubação. O menor número de repastos foi observado no grupo 33/40 exceto para o primeiro estádio (grupo 28/70). O período de desenvolvimento ninfal foi significativamente reduzido no grupo 33/40; entretanto, o percentual de mortalidade deste grupo foi alto, e os insetos não conseguiram realizar a muda imaginal.

The objective of the present paper was to study the development of R. neglectus in the laboratory under different conditions of temperature and humidity. Three groups were prepared: 33/40 (33+/- 1 degree C and 40% +/-5% UR), 33/70 (33+/- 1 degree C and 70% +/-5% UR), and 28/70 (28+/- 1 degree C and 70% +/-5% UR). All these groups were observed daily to evaluate the eggs' incubation period, the development period of each instar nymph, the mortality rate of each stage, the frequency of feeding and the hatching - adult ecdysis period. The embryonic development showed significant differences between the treatment given, the group 33/40 presented the lowest incubation period. The lowest bloodmeals number was observed in the group 33/40 except for the first instar (group 28/70). The period of nymphal development was significantly reduced in the group 33/40, however, the mortality was high and the specimens did not reach the adult phase.

[Development of Rhodnius pictipes Stal, 1872 fed on mice and through a silicone membrane (Hemiptera, Reduviidae, Triatominae)]. / Desenvolvimento de Rhodnius pictipes Stal, 1872 alimentado através de membrana de silicone e em camundongos (Hemiptera, Reduviidae, Triatominae).

Rhodnius pictipes (Hemiptera, Reduviidae) from Serra Norte, State of Pará, Brazil, acclimatized in an insectary at the Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos, Departamento de Entomologia, Instituto Oswaldo Cruz, were fed through a silicone membrane. In order to know the viability and the efficiency of this membrane compared with insects fed on mice, the number of bloodmeals taken, period of development of the five nymphal instars, longevity of adults, average amount of blood intake in each meal and percent of mortality were observed. A total of 310 insects, were used, comprising 50 nymphs of each instar, as well as 30 male and 30 female adults. Insects fed artificially had reduced minimal and maximal periods of development than the group fed on mice. The largest relative increase of body weight was observed in the 2nd instar followed by the 1st, and the amount of blood ingested increased during the development, to the 5th instar for both groups. There were no significant differences between the groups fed artificially and in vivo according to Tukey's test for p > 0.05. The percent of mortality in the 1st instar was 18% for artificially fed and 16% for the group fed on mice; these percentages decreased as insects developed until the 4th instar, without mortality, returning to increase in the 5th instar. R. pictipes was shown to be easily adaptable to artificial feeding, and could be considered as an important and viable experimental model.

[Biology of Rhodnius pictipes Stal, 1872 under laboratory conditions (Hemiptera, Reduviidae, Triatominae)]. / Biologia do Rhodnius pictipes Stal, 1872 em condições de laboratorio (Hemiptera, Reduviidae, Triatominae).

Rhodnius pictipes Stal, 1872 is a silvatic species with a widespread distribution in South America, found in nine Brazilian states, naturally infected by Trypanosoma cruzi and T. rangeli. The individual rearing of this species under laboratory conditions, allowed the following biological aspects to be observed: incubation time, search for first meal after eclosion or moult, time-lapse between presentation of the blood meal and the beginning of feeding, duration of blood meal, time and place of defecation, number of blood meals, duration of each instar and adult longevity, and time required from egg to adult.