Biology of Triatoma carcavalloi Jurberg, Rocha & Lent, 1998 under laboratory conditions

Abstract

Introduction:Triatoma carcavalloi is a wild species that is found in sympatry with Triatoma rubrovaria and Triatoma circummaculata, which are vectors of Trypanosoma cruzi currently found in rural areas of Rio Grande do Sul, Brazil. Methods: Fertility was assessed and to determine the incubation period, the eggs were observed until hatching. The first meal was offered to 1 st stage nymphs. The intermolt period was also determined. The number of blood meals was quantified at each nymphal stage and the resistance to fasting as the period between ecdysis and death. Mortality was assessed and longevity was determined by recording the time that elapsed from molting to the adult stage and until death. The developmental cycle was assessed by recording the length in days of each stage from molting to adult hood. Results: The average incubation period was 22.7 days. The average first meal occurred 3.1 days after hatching. The 5 th stage nymph to adult intermolting period was the longest at 193.4 days. The average number of feedings during nymphal development was 13.4. The resistance to fasting assay indicated that the 3 rd , 4 th and 5 th stage nymphs presented higher resistance than did adults. The highest mortality rate was observed in the 3 rd stage nymphs (22.2%). The average length of adult survival was 25.6 weeks, and the average total life cycle lasted 503.4 days. Conclusions:This study is the first report on the biology of T. carcavalloi that fed on mice. The presented findings expand the bionomic knowledge of these species.

Life cycle and vectorial competence of Triatoma williami (Galvão, Souza e Lima, 1965) under the influence of different blood meal sources

“…However, it was observed that the duration of N3 was shorter in both groups. This reduction in the third stage was not observed in the cycles of T. arthurneivai (Juarez, 1970), T. dimidiata (Reyes & Angulo, 2009), T.carcavalloi (Cardozo-de-almeida et al, 2014), but it occurred with T.…”

“…The mortality pattern of T.williami in the nymphal stages was irregular as it happens with many other Triatominae species (Braga et al, 1998;Carbajal de la Fuente et al, 2010;Cardozo-de-Almeida et al, 2014;Rodrigues et al, 2007). The cumulative mortality until the fifth nymphal instar of T. williami was higher in BIR group as was also shown by T. klugi (Emmanuelle-Machado et al, 2002), Rhodnius neglectus (Diotaiuti & Dias, 1987), T. brasiliensis, T.…”

“…After the moultings, nymphs and even more the adult of T. williami fasted for longer periods, when compared to T. maculata and T. rubrovaria.The spontaneous fasting period after the moulting of T.williami adults, especially in the BIR group, exceeded the survival period of male and female compulsory fasting of many species such as T. brasiliensis, T. vitticeps, T. nitida, T.rubrofasciata and T.sordida (Cortéz & Gonçalves, 1998;Costa & Perondini, 1973;Galvão et al, 1996;Gonçalves et al, 1989;Juarez & Silva, 1982). According to Cardozo-de-almeida et al (2014), one of the main barriers for the control of insects through the use of insecticides with residual action is the resistance of insects to fasting. This resistance is an important survival strategy when in adverse situations or food privation (Jurberg & Costa, 1989).…”

“…The bionomic characterization of wild species that possibly may invade anthropic environments is important to evaluate the efficiency of these insects as vectors of T.cruzi and also to support the modeling of control strategies (Cardozo-de- Almeida et al, 2014;Durán et al, 2014). In fact, a large number of studies about bionomic and behavioral aspects of the Triatomines suggests an increasing interest in establishing control measures and also reflects their use as an excellent biological models for studies about insect hematophagy and physiology (Lazzari et al, 2013).The life cycle of triatomines varies according to the species, the environmental condition and blood meal source (Carbajal de la Fuente et al, 2010;Schofield, 1985), so the general goals of this study were to describe, for the first time, the biological cycle of T.…”

On triatomines, cockroaches and haemolymphagy under laboratory conditions: new discoveries

“…With the increase in the literature regarding the feeding sources of triatomines over the last 30 years, haemolymphagy has been observed in more than 20 species belonging to the genera Belminus ( Lent & Wygodzinsky 1979 , Sandoval et al 2000 , 2004 , 2010 , 2013 ), Eratyrus ( Miles et al 1981) , Psammolestes ( Carcavallo et al 1998 , Noireau et al 2005a ), Panstrongylus ( Carcavallo et al 1998 , Garrouste 2009) , Rhodnius ( Brumpt 1914 , Marinkelle 1965 , Piñero et al 1988) and Triatoma ( Brumpt 1914 , Ryckman 1951 , Phillips 1960 , Lent & Wygodzinsky 1979 , Salvatella & Calegari 1991 , Salvatella et al 1994 , Lorosa et al 2000 , Ruas-Neto et al 2001 , Vezzani et al 2001 , Emmanuelle-Machado et al 2002 , Freitas et al 2005 , Noireau et al 2005a , Silva et al 2005 , Zeledón et al 2010 , Alves et al 2011 , Pontes et al 2011 , Cardozo-de-Almeida et al 2014) . The ability to use haemolymphagy is suggested to represent an important survival strategy under natural conditions for some species, resulting in optimised use of available nutrition resources and an increase in the probability of survival when vertebrate hosts are absent ( Salvatella et al 1994 , Lorosa et al 2000 , Ruas-Neto et al 2001 , Alves et al 2011) .…”