Detomidine

Rhodnius prolixus used in this study were obtained from a long-established colony in our laboratory (originally collected in Honduras in the 1990s). Insects were fed citrated rabbit blood on a monthly basis obtained from CECAL (Fiocruz, Rio de Janeiro, Brazil) offered through an artificial feeder at 37°C, alternating with blood from anaesthetized chickens [intraperitoneal injections of a mixture of ketamine (20 mg kg⁻¹; Cristália, Brazil) and detomidine (0.3 mg kg⁻¹; Syntec, Brazil)] and mice [intraperitoneal injections of a mixture of ketamine (150 mg kg⁻¹; Cristália) and xylazine (10 mg kg⁻¹; Bayer, Brazil)]. The colony was maintained at 27 ± 1°C, 51 ± 7% RH, and exposed to a natural illumination cycle. All experiments using live animals were performed following FIOCRUZ guidelines on animal experimentation and were approved by the Ethics Committee on Animal Use (CEUA/FIOCRUZ) under the approved protocol number LW 8/17.

The R. prolixus colony used in our study originated from insects collected in Honduras in the 90’s. Insects were maintained by the Vector Behavior and Pathogen Interaction Group at the René Rachou Institute. Experimental bugs were fed citrated rabbit blood obtained from CECAL (Fiocruz, Rio de Janeiro, Brazil) offered through an artificial feeder at 37°C, alternating with blood from anesthetized chickens. Chickens were anesthetized with intraperitoneal injections of a mixture of ketamine (20 mg/kg; Cristália, Brazil) and detomidine (0.3 mg/kg; Syntec, Brazil). The colony was maintained at 26±1°C, 65±10% RH and exposed to a natural illumination cycle.
The T. cruzi CL strain, originally isolated from naturally infected Triatoma infestans [21 (link)] was used to infect the triatomines. Parasites were cultured by twice a week passages in LIT (liver-infusion tryptose) medium supplemented with 15% fetal bovine serum, 100 mg/ml streptomycin and 100 units/ml penicillin. The cultured parasites were passed through triatomines and mice every four months to maintain strain infectivity.

Rhodnius prolixus were obtained from a colony maintained by the Vector Behavior and Pathogen Interaction Group at René Rachou Institute (FIOCRUZ, Minas, Brazil), which was established from insects collected in Honduras around 1990. The colony was maintained under controlled temperature (26 ± 1°C), relative humidity (65 ± 10%), and natural illumination cycle. Insects were consistently fed on diverse sources of blood that included mice, chicken, and a membrane feeder offering citrated rabbit blood at 37°C. Mice and chickens were anesthetized with intraperitoneal injections of ketamine (150 mg/kg; Cristália, Brazil) plus xylazine (10 mg/kg; Bayer, Brazil), and ketamine (20 mg/kg; Cristália, Brazil) plus detomidine (0.3 mg/kg; Syntec, Brazil), respectively. Rhodnius prolixus 4^th instar nymphs starved for 30 days were used in all experiments.