| Vol. 97(7) October 2002 |
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Feeding and Defaecation Behaviour of Triatoma patagonica (Del Ponte, 1929) (Hemiptera: Reduviidae) Vol. 97(7): 1063-1065, October 2002
Julieta Nattero+, Liliana B Crocco, Claudia S Rodríguez
Cátedra de Introducción a la Biología, Facultad de Ciencias Exactas Físicas y Naturales, Universidad Nacional de Córdoba, Vélez Sarsfield 299, 5000 Córdoba, Argentina
Among the vectors of Chagas disease, Triatoma patagonica is a species in the process of adaptation to the human environment being recently registered in urban and suburban zones. However, its importance as a vector of Chagas disease is unknown. The aim of this work was to evaluate two aspects of vectorial competence: the feeding behaviour and the defaecation pattern. These processes were studied in females of T. patagonica fed ad libitum on a restrained pigeon. The results showed that the blood meal size was negatively correlated with the time of first defaecation (r = -0.42). The first defaecation was emitted before the first 10 min and defaecations during feeding were frequent. A total of 73% of females, defaecated during the first 30 min post-feeding. These results suggest that if this species subsequently colonizes the domicile, it would be capable of transmitting Trypanosoma cruzi.
Key words: Triatoma patagonica - feeding - defecation - peridomestic - Chagas disease vector - Argentina
Among the peridomestic species of Chagas disease vectors, Triatoma patagonica (Del Ponte, 1929) has the most southerly distribution. It is only to be found in Argentina (Lent & Wygodzinsky 1979), 20º to 50º southern latitude and 750 m of altitude (Carcavallo et al. 1999). It was found naturally infected by Trypanosoma cruzi (Chagas 1909) (Lent & Wygodzinsky 1979) and in Río Colorado (province of Río Negro) it was the only peridomestic species found in houses both in urban and suburban areas (Ferrero et al. 1999). These last records, added to the permanence in the peridomicile, point the need to determine how competent T. patagonica is as a vector of Chagas disease, especially in aspects related to feeding and defaecation. These two processes (feeding and defaecation) have been thoroughly analyzed in triatomines as they are closely related to the development and transmission of T. cruzi (Mello 1980, Kirk & Schofield 1987, Trumper & Gorla 1991, Crocco & Catalá 1996). These processes are well known in domestic species like T. infestans (Klug, 1934) (Forattini et al. 1982, Friend & Smith 1985, Trumper & Gorla 1991) and Rhodnius prolixus (Stal, 1859) (Forattini et al. 1982, Friend & Smith 1985). Nevertheless, very little is known about peridomestic species including T. patagonica (Del Ponte, 1929) about which only facts relating to its life cycle and habitats are known (Martínez et al. 1985, Carcavallo et al. 1998). From an epidemiological point of view, it is very important to have knowledge related to feeding and defaecation, the aim of this work is to evaluate the feeding pattern and the defaecation behaviour in adults of T. patagonica.
ACKNOWLEDGMENT
To the Servicio Nacional de Chagas for supplying insects.
Fig. 1 | Fig. 2 | Fig. 3 | Table I | Table II
This work received financial support from Secyt (Argentina). +Corresponding author. Fax: +54-351-433.1056 E-mail: jnattero@efn.uncor.edu Received 10 January 2002 Accepted 22 July 2002 |
