Susceptibility characterization of residual Brazilian populations of Triatoma infestans Klug, 1834 (Hemiptera: Reduviidae) to deltamethrin pyrethroid

INTRODUCTION: Despite years of efforts towards the elimination of Triatoma infestans in Brazil, residual foci still persist in some areas of the States of Bahia and Rio Grande do Sul. The persistence of these T. infestans populations in the country has two different origins of equal concern: operational failures or insecticide resistance. Thus, the objective of this study was to characterize the susceptibility profile of the residual Brazilian populations of T. infestans to deltamethrin. METHODS: The susceptibility reference lineage was derived from Cipein/Argentina. The populations studied were manually collected using a dislodging agent in peridomiciles in the States of Bahia (Novo Horizonte) and of Rio Grande do Sul (Santa Rosa and Doutor Maurício Cardoso). Serial dilutions of deltamethrin were prepared and applied at the dorsal abdomen of first instar nymphs. The control group received only pure acetone. Mortality was evaluated after 72h. Qualitative tests assessed the mortality of a diagnostic dose of 1xLD99 (2.76ng a.i./nymph) determined for the susceptibility reference lineage. RESULTS: The susceptibility profile characterization of the T. infestans populations revealed an RR50 ranging from 1.73 to 3.26. The mortality percentage in response to a diagnostic dose was 100%. The results obtained in the quantitative and qualitative assays corresponded for all populations. CONCLUSIONS: The results of this study indicate that the persistence of residual foci of T. infestans in Bahia and Rio Grande do Sul is not related to insecticide resistance but may be associated with operational failures. In Rio Grande do Sul, we must consider the possibility of continuous reinfestation by Argentinian individuals, which justifies active and efficient epidemiological surveillance.

IMPACTOS DA HIDRELÉTRICA SAMUEL SOBRE AS COMUNIDADES DE PEIXES DO RIO JAMARI (RONDÔNIA, BRASIL)

A Usina Hidrelétrica de Samuel está localizada no rio Jamari, primeiro afluente da margem direita do rio Madeira, cerca de 56 km abaixo de Porto Velho-RO. A hidrelétrica teve sua construção iniciada em abril/1982 e entrou em operação a partir de abril/89. O estudo comparativo da ictiofauna, na área de influência daquela hidrelétrica, nas fases de pré e pós-enchimento do reservatório, mostra que as comunidades de peixes sofreram profundas alterações pelo represamento: houve redução da diversidade no reservatório, bem como o aumento de pira-nha-preta (Serrasalmuts rhombeus),tucunaré (Cichla monoculus),aracu-comum (Schizodon fasciatus)e mapará (Hypophthalmus edentatus);imediatamente à jusante da represa houve um aumento de mandi (Pimelodus blochii)\além disso, houve redução dos peixes detritívoros e frugívoros e aumento dos piscivoros.As comunidades de peixes do canal principal do Jamari parecem ter sido mais influenciadas pelo represamento do rio do que aquelas dos lagos marginais. A atividade pesqueira, antes restrita à foz do Jamari, foi intensificada na área do reservatório e isso vem constituindo-se num sério obstáculo para o manejo da pesca. Estes aspectos são comentados e algumas ações são propostas para melhor gerenciamento da pesca c sustentabilidade dos recursos pesqueiros.

Prodromus plantarum Capensium :quas in promontorio Bonæ Spei Africes, annis 1772-1775 /collegit Carol. Pet. Thunberg.

1800 v.2

Prodromus plantarum Capensium :quas in promontorio Bonæ Spei Africes, annis 1772-1775 /collegit Carol. Pet. Thunberg.

1794a v.1

Biologia Centrali-Americana :zoology, botany and archaeology /edited by Frederick Ducane Godman and Osbert Salvin.

Introduction

Biologia Centrali-Americana :zoology, botany and archaeology /edited by Frederick Ducane Godman and Osbert Salvin.

Mammalia

Biologia Centrali-Americana :zoology, botany and archaeology /edited by Frederick Ducane Godman and Osbert Salvin.

Aves. v. 1. Introduction -- Subclass Aves Carinate. Order Passeres.

Biologia Centrali-Americana :zoology, botany and archaeology /edited by Frederick Ducane Godman and Osbert Salvin.

Aves. v. 2. Subclass Aves Carinate. Order[s]: Passeres (contd.), Macrochires, Pici, Coccyges, Psitta

Biologia Centrali-Americana :zoology, botany and archaeology /edited by Frederick Ducane Godman and Osbert Salvin.

Aves. v. 3. Subclass Aves Carinate. Order[s]: Striges, Accipitres, Steganopodes, Phoenicopteri, Colu

Biologia Centrali-Americana :zoology, botany and archaeology /edited by Frederick Ducane Godman and Osbert Salvin.

Aves. v. 4. Plates.

Biologia Centrali-Americana :zoology, botany and archaeology /edited by Frederick Ducane Godman and Osbert Salvin.

Reptilia and Batrachia

Biologia Centrali-Americana :zoology, botany and archaeology /edited by Frederick Ducane Godman and Osbert Salvin.

Pisces

Biologia Centrali-Americana :zoology, botany and archaeology /edited by Frederick Ducane Godman and Osbert Salvin.

Land and Freshwater Mollusca

Biologia Centrali-Americana :zoology, botany and archaeology /edited by Frederick Ducane Godman and Osbert Salvin.

Arachnida Araneidea