Feeding behavior of Triatoma vitticeps (Reduviidae: Triatominae) in the state of Minas Gerais, Brazil

• Published in: Memórias do Instituto Oswaldo Cruz Vol. 106; no. 1; pp. 16 - 22
• Main Authors: de Souza, Rita de Cássia Moreira, Soares, Adriana C, Alves, Ceres Luciana, Lorosa, Elias Seixas, Pereira, Marcos Horácio, Diotaiuti, Liléia
• Format: Journal Article
• Language: English; Portuguese
• Published: Brazil Fundação Oswaldo Cruz, Fiocruz 01.02.2011; Instituto Oswaldo Cruz, Ministério da Saúde; Fundação Oswaldo Cruz (FIOCRUZ)
• Subjects: Animals; Armadillos; Birds; Brazil; Cattle; cibarial pump; Dogs; feeding behavior; Feeding Behavior - physiology; Gastrointestinal Contents; hematophagic; hemiptera; Humans; Insect Vectors - physiology; Lizards; Opossums; PARASITOLOGY; Rodentia; saliva; Saliva - chemistry; Saliva - physiology; Triatoma - physiology; TROPICAL MEDICINE; Brazil; saliva; cibarial pump; hematophagic; feeding behavior; hemiptera
• ISSN: 1678-8060; 0074-0276; 1678-8060; 0074-0276
• DOI: 10.1590/s0074-02762011000100003

The objective of this study was to evaluate the feeding behavior of Triatoma vitticeps through the identification of its food sources and the characterization of the blood ingestion process. In addition, we aimed to verify if the saliva of this vector interferes with the perception of the host during the feedings by creating a nervous impulse. Here, we demonstrated that the T. vitticeps saliva reduces, gradually and irreversibly, the amplitude of the compound action potential of the nervous fibre, which helps decrease the perception of the insect by the host. The precipitin reaction demonstrated the feeding eclecticism of this vector, with the identification of eight food sources - most of them found simultaneously in the same insect. The analysis of the electrical signals produced by the cibarial pump during meals demonstrated that the best feeding performance of T. vitticeps nymphs that fed on pigeons is mainly due to the higher contraction frequency of the pump. The longer contact period with the host to obtain a complete meal compared with other triatominae species of the same instar could favor the occurrence of multiple blood sources in T. vitticeps under natural conditions, as it was evidenced by the precipitin test.