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Biologia do Triatoma nitida Usinger, 1939 em laboratório (Hemiptera: Reduviidae)
Galv?o, Cleber;Jurberg, José;Cunha, Vanda;Mello, Rubens Pinto de;
Memórias do Instituto Oswaldo Cruz , 1995, DOI: 10.1590/S0074-02761995000500024
Abstract: triatoma nitida is a wild species occurring in mexico and central america. in order to establish the length of its life cycle and transmission potential, the following parameters were observed: the incubation period, the interval between hatching, or moulting, and the first feeding; the number of blood meals and the time of development. the time-lapse before the bite, the length of feeding and the interval between the end of the blood meal and defecation, as well as the site of defecation were also analyzed. average length of the egg incubation period was 18.2 days. time interval between the food source offering and the bite was less than 4 min in 60//of the analyzed cases, except in the fifth instar, where only 38//of the insects began feeding in less than 5 min. the blood-sucking period was long and rising until the fifth instar, decreasing in adults, and ranging from 1 min to 2 and a half hours. only 26//of the blood meals were followed by defecations within 20 min. the average length of the life cycle was 897.5 days.
Epidemiology of Chagas disease in Guatemala: infection rate of Triatoma dimidiata, Triatoma nitida and Rhodnius prolixus (Hemiptera, Reduviidae) with Trypanosoma cruzi and Trypanosoma rangeli (Kinetoplastida, Trypanosomatidae)
Monroy, Carlota;Rodas, Antonieta;Mejía, Mildred;Rosales, Regina;Tabaru, Yuichiro;
Memórias do Instituto Oswaldo Cruz , 2003, DOI: 10.1590/S0074-02762003000300003
Abstract: a five-year domiciliary collection in the 22 departments of guatemala showed that out of 4,128 triatomines collected, 1,675 were triatoma dimidiata (latreille, 1811), 2,344 were rhodnius prolixus stal 1859, and only 109 were t. nitida usinger 1939. the chagas disease parasite, trypanosoma cruzi, was found in all three species. their natural infection rates were similar in the first two species (20.6%; 19.1%) and slightly lower in t. nitida(13.8%). however there was no significant difference in the infection rates in the three species (p = 0.131). t. dimidiata males have higher infection rates than females (p = 0.030), whereas for r. prolixus there is no difference in infection rates between males and females (p = 0.114). the sex ratios for all three species were significantly skewed. more males than females were found inside houses for t. dimidiata (p < 0.0001) and t. nitida (p = 0.011); a different pattern was seen for r. prolixus (p = 0.037) where more females were found. sex ratio is proposed as an index to show the mobility of t. dimidiata in different populations. t. dimidiata is widely distributed in the country, and is also the main vector in at least ten departments, but r. prolixus with higher vectorial capacity is an important vector in at least two departments.
Epidemiology of Chagas disease in Guatemala: infection rate of Triatoma dimidiata, Triatoma nitida and Rhodnius prolixus (Hemiptera, Reduviidae) with Trypanosoma cruzi and Trypanosoma rangeli (Kinetoplastida, Trypanosomatidae)
Monroy Carlota,Rodas Antonieta,Mejía Mildred,Rosales Regina
Memórias do Instituto Oswaldo Cruz , 2003,
Abstract: A five-year domiciliary collection in the 22 departments of Guatemala showed that out of 4,128 triatomines collected, 1,675 were Triatoma dimidiata (Latreille, 1811), 2,344 were Rhodnius prolixus Stal 1859, and only 109 were T. nitida Usinger 1939. The Chagas disease parasite, Trypanosoma cruzi, was found in all three species. Their natural infection rates were similar in the first two species (20.6%; 19.1%) and slightly lower in T. nitida(13.8%). However there was no significant difference in the infection rates in the three species (p = 0.131). T. dimidiata males have higher infection rates than females (p = 0.030), whereas for R. prolixus there is no difference in infection rates between males and females (p = 0.114). The sex ratios for all three species were significantly skewed. More males than females were found inside houses for T. dimidiata (p < 0.0001) and T. nitida (p = 0.011); a different pattern was seen for R. prolixus (p = 0.037) where more females were found. Sex ratio is proposed as an index to show the mobility of T. dimidiata in different populations. T. dimidiata is widely distributed in the country, and is also the main vector in at least ten departments, but R. prolixus with higher vectorial capacity is an important vector in at least two departments.
A comparative study of the male external genitalia of Triatoma neotomae Neiva, 1911 and Triatoma nitida Usinger, 1939 (Hemiptera: Reduviidae)
Lent, Herman;Juberg, José;
Memórias do Instituto Oswaldo Cruz , 1992, DOI: 10.1590/S0074-02761992000500026
Abstract: the morphological comparative study of the phallus organs, of both species, shown five structures wich may be used as taxonomic characters. they are: parameres (pa), median process pygophore (prp), basal plate (epbi), gonopore (prg) and endosoma process (pren).
Feeding, defecation, and development times of Meccus longipennis Usinger, 1939 (Hemiptera: Reduviidae: Triatominae) under laboratory conditions
Martínez-Ibarra, José Alejandro;Grant-Guillén, Yunuen;Martínez-Grant, Diana Monserrat;
Memórias do Instituto Oswaldo Cruz , 2003, DOI: 10.1590/S0074-02762003000700007
Abstract: aspects related to hatching, time-lapse between presenting the blood-meal and beginning of feeding, feeding time, postfeed defecation delay, mortality, and fecundity for each stage of meccus longipennis life-cycle were evaluated. the bugs were maintained in a dark incubator at 27 ± 1oc and 80 ± 5% rh, were fed weekly and checked daily for ecdysis or death. the hatching rate observed for 300 eggs was 76.7% and the average time of hatching was 19.8 days. mean time-lapse between presentation of the blood meal and the beginning of feeding was under 5 min in nymphal stages and postfeed defecation delay was under 10 min in most stages, except in fourth and fifth stages. mean feeding time was longer than 10 min in most stages, except in fourth stage. one hundred thirty-one nymphs (n) (65.5%) completed the cycle and the average time from ni to adult was 192.6 ± 34.8 days. the average span in days for each stage was 18.1 for ni, 21.4 for nii, 29.5 for niii, 45.5 for niv and 55.9 for nv. the number of bloodmeals at each nymphal stage varied from 1 to 5. the mortality rate was 3.29 for ni, 6.8 for nii, 2.92 for niii 3.76 for niv, and 10.16 for nv nymphs. the average number of eggs laid per female in a 9-month period was 615.6. based on our results, we conclude that m. longipennis has some biological and behavioral characteristics which influence its capacity of becoming infected and transmitting trypanosoma cruzi to human populations in those areas of mexico where it is currently present.
Influence of the blood meal source on the biology of Meccus picturatus Usinger 1939 (Hemiptera: Reduviidae: Triatominae) under laboratory conditions
Martínez-Ibarra, José Alejandro;Novelo López, Mónica;Hernández Robles, María del Rosario;Grant Guillén, Yunuen;
Memórias do Instituto Oswaldo Cruz , 2003, DOI: 10.1590/S0074-02762003000200011
Abstract: aspects related to hatching, time-lapse between presenting the blood meal and beginning of feeding, feeding time, postfeed defecation delay,life time, mortality and fecundity for each stage of meccus picturatus, life-cycle were evaluated and compared in two cohorts of m. picturatus fed on hens or rabbits. the hatching rate observed for each of the two studied groups of eggs was 78.1% (n = 2298) on the group fed on hens and 82.1% (n = 2704) on that fed on rabbits, and the average time of hatching was 20 days. mean time-lapse for beginning feeding was under 3 min in nymphal stages and postfeed defecation delay was under 10 min in all stages, in both cohorts. mean feeding time was significantly (p < 0.05) shorter in triatomines fed on hens than on rabbits. a similar number of nymphs of each cohort, 69 fed on hens (34.5%) and 68 fed on rabbits (34%), completed the cycle. no significantly (p > 0.05) differences were recorded among the average times from ni to adult in the cohort fed on hens (196.8 ± 15.8 days) and the average time in the cohort fed on rabbits (189.5 ± 22.9). the average span in days for each stage fed on hens was not significantly different to the average span for each stage fed on rabbits. the number of blood meals at each nymphal stage varied from 1 to 6 in both cohorts. the mortality rates were higher on fifth nymphal stage, in both cohorts. no significant (p > 0.05) differences were recorded on mortality rates on most nymphal stages of both cohorts. the average number of eggs laid per female from the cohort fed on hens in a 9-month period was 791.1, whereas the average number of eggs in the cohort fed on rabbits was 928.3.
Influence of the blood meal source on the biology of Meccus picturatus Usinger 1939 (Hemiptera: Reduviidae: Triatominae) under laboratory conditions  [cached]
Martínez-Ibarra José Alejandro,Novelo López Mónica,Hernández Robles María del Rosario,Grant Guillén Yunuen
Memórias do Instituto Oswaldo Cruz , 2003,
Abstract: Aspects related to hatching, time-lapse between presenting the blood meal and beginning of feeding, feeding time, postfeed defecation delay,life time, mortality and fecundity for each stage of Meccus picturatus, life-cycle were evaluated and compared in two cohorts of M. picturatus fed on hens or rabbits. The hatching rate observed for each of the two studied groups of eggs was 78.1% (n = 2298) on the group fed on hens and 82.1% (n = 2704) on that fed on rabbits, and the average time of hatching was 20 days. Mean time-lapse for beginning feeding was under 3 min in nymphal stages and postfeed defecation delay was under 10 min in all stages, in both cohorts. Mean feeding time was significantly (P < 0.05) shorter in triatomines fed on hens than on rabbits. A similar number of nymphs of each cohort, 69 fed on hens (34.5%) and 68 fed on rabbits (34%), completed the cycle. No significantly (P > 0.05) differences were recorded among the average times from NI to adult in the cohort fed on hens (196.8 ± 15.8 days) and the average time in the cohort fed on rabbits (189.5 ± 22.9). The average span in days for each stage fed on hens was not significantly different to the average span for each stage fed on rabbits. The number of blood meals at each nymphal stage varied from 1 to 6 in both cohorts. The mortality rates were higher on fifth nymphal stage, in both cohorts. No significant (P > 0.05) differences were recorded on mortality rates on most nymphal stages of both cohorts. The average number of eggs laid per female from the cohort fed on hens in a 9-month period was 791.1, whereas the average number of eggs in the cohort fed on rabbits was 928.3.
Feeding, defecation, and development times of Meccus longipennis Usinger, 1939 (Hemiptera: Reduviidae: Triatominae) under laboratory conditions  [cached]
Martínez-Ibarra José Alejandro,Grant-Guillén Yunuen,Martínez-Grant Diana Monserrat
Memórias do Instituto Oswaldo Cruz , 2003,
Abstract: Aspects related to hatching, time-lapse between presenting the blood-meal and beginning of feeding, feeding time, postfeed defecation delay, mortality, and fecundity for each stage of Meccus longipennis life-cycle were evaluated. The bugs were maintained in a dark incubator at 27 ± 1oC and 80 ± 5% rh, were fed weekly and checked daily for ecdysis or death. The hatching rate observed for 300 eggs was 76.7% and the average time of hatching was 19.8 days. Mean time-lapse between presentation of the blood meal and the beginning of feeding was under 5 min in nymphal stages and postfeed defecation delay was under 10 min in most stages, except in fourth and fifth stages. Mean feeding time was longer than 10 min in most stages, except in fourth stage. One hundred thirty-one nymphs (N) (65.5%) completed the cycle and the average time from NI to adult was 192.6 ± 34.8 days. The average span in days for each stage was 18.1 for NI, 21.4 for NII, 29.5 for NIII, 45.5 for NIV and 55.9 for NV. The number of bloodmeals at each nymphal stage varied from 1 to 5. The mortality rate was 3.29 for NI, 6.8 for NII, 2.92 for NIII 3.76 for NIV, and 10.16 for NV nymphs. The average number of eggs laid per female in a 9-month period was 615.6. Based on our results, we conclude that M. longipennis has some biological and behavioral characteristics which influence its capacity of becoming infected and transmitting Trypanosoma cruzi to human populations in those areas of Mexico where it is currently present.
Madurez ovárica y proteínas del vitelo en hembras de Triatoma Barberi Usinger, 1939 (Hemiptera: Reduviidae, Triatominae) infectadas...
Arturo Ramírez Cruz,Benjamín Nogueda Torres,Ricardo Alejandre Aguilar,Imelda Martínez Morales
Acta zoológica mexicana , 2005,
Abstract: Hembras de Triatoma barberi fueron infectadas experimentalmente con Trypanosoma cruzi a partir del segundo estadio ninfal, con el fin de detectar posibles alteraciones en los ovarios y en las proteínas del vitelo del huevo. En las hembras infectadas y en las hembras testigo, se tomaron en cuenta los cambios morfológicos que se presentaron en los ovarios durante su maduración, así como los patrones electroforéticos de las proteínas del vitelo del huevo. La morfología de los ovarios de Triatoma barberi no fue afectada por la infección con Trypanosoma cruzi; los patrones de crecimiento de los ovarios hasta su madurez fueron los mismos en las hembras testigo y en las infectadas. Las proteínas del vitelo del huevo, en ambos grupos de hembras, no presentaron diferencias en los patrones electroforéticos.
Distribui??o Geográfica e Dispers?o Alti-latitudinal de Alguns Gêneros e Espécies da Tribo Triatomini Jeannel, 1919 (Hemiptera, Reduviidae, Triatominae)
Galv?o, Cleber;Jurberg, José;Carcavallo, Rodolfo U;Segura, Carlos A Mena;Girón, Itamar Galíndez;Casas, Susana I Curto de;
Memórias do Instituto Oswaldo Cruz , 1998, DOI: 10.1590/S0074-02761998000100007
Abstract: geographical distribution and alti-latitudinal dispersion of some genera and species of the tribe triatomini jeannel, 1919 (hemiptera, reduviidae, triatominae) - with the currently known distribution of genera and species of the tribe triatomini jeannel, 1919, maps and diagrams were prepared, showing the geographical area occupied by the species and their respective dispersion in grades of latitude and altitude. two genera are not treated: panstrongylus berg, 1879, already published and triatoma laporte, 1832, that is being published partially in several articles. genus eratyrus stal, 1859, has two species, while dipetalogaster usinger, 1939, mepraia mazza, gajardo & joerg, 1940, paratriatoma barber, 1938 and recently created genus hermanlentia jurberg & galv?o, 1997, have only one each. the study of these maps and diagrams permits a better knowledge about some ecological requirements of chagas' disease vectors and detects gaps in the geographical distribution, where the species were not found but probably they could be prevalent
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