BackgroundVector control can contribute to the development of resistance to insecticides in malaria vectors. As the swamps and wetlands used for some agricultural activities constitute productive breeding sites for many mosquito species, agricultural pest control may increase the selection pressure for insecticide resistance in mosquitoes. Understanding the use of agrochemicals by farmers is important to plan and initiate effective integrated pest and vector management interventions.MethodsA knowledge–attitude–practice study, using questionnaires, was undertaken with 102 rice farmers in Tiassalé and 106 vegetable farmers in Dabou (South Côte d’Ivoire) in order to generate information on pesticide usage. In addition, insecticide susceptibility bioassays were conducted using adult mosquitoes obtained from larvae collected within farms, and the persistence of agricultural pesticides in the farming environment, including sediment and mosquito breeding site water, was investigated by HPLC.ResultsHerbicides and insecticides appeared to be the most frequently used pesticides for both crops. Amino phosphonates (mostly glyphosate) represented the most used herbicides (45 % for rice up to 89 % for vegetables). Pyrethroids appeared to be the most used insecticides (accounting for 90 % of all the insecticide use reported). Approximately 75 % of respondents had not been to school and do not understand product labels. Only about 45 % of farmers respect the recommended pesticide dosage and about 10–15 % of pesticides used for rice and vegetable, respectively, are not recommended for these crops. As per WHO criteria, the mosquito local populations from the two localities were resistant to three of the four insecticides tested, as mortalities were less than 35 % for deltamethrin, DDT and bendiocarb. Higher susceptibility was observed for malathion, although the population was considered resistant in Dabou (80 % mortality) and susceptible in Tiassalé (98 % mortality). With the exception of glyphosate, residues from each of six chemicals tested for were detected in each of the sites visited in the two localities.ConclusionThe study describes the use of insecticides and herbicides on crops and highlights the importance of considering agriculture practices when attempting to manage resistance in malaria vectors. Inter-sectoral collaboration between agriculture and public health is required to develop efficient integrated pest and vector management interventions.Electronic supplementary materialThe online version of this article (doi:10.1186/s12936-016-1481-5) contains supplementary material, which is available to authorized users.

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The present study aims to assess the diversity of fish in the lower basin of the Comoé River. In a specific manner, it comes to doing survey, to identify the factors determining the ichtyological diversity of this river. Data presented are from experimental and artisanal fisheries during eight seasonal campaigns, from June 2014 to May 2017. This study identified 67 fish species divided into 11 orders and 30 families. Of these 67species, 16 are reported for the first time in the river basin. Perciformes (40.30 %), Siluriformes (17.91 %) and Osteoglossiformes (11.94 %) are the most represented. In terms of abundance, the highest value, that is, 2428 out of 7265 specimens captured, or 33.42 %, was recorded at Adjékro and the lowest, that is 583, or 8.02 % at Moossou. From a distribution point of view, the Shannon-Weaver (H ') index and equitability (E) values indicate that the fish populations are generally balanced. The parameters related to mineralization (pH and conductivity) and transparency appear to be the most discriminating in the distribution of fish in the waters.

The lagoons are high biological and economic potential areas exploited by thousands of fishermen. Otherwise, the persistent use of pesticides in fisheries may be perceived as a response of fishermen to lower yields and, consequently, to reduced income from fishing activities. In this context, the hypothesis of a lack of profitability concerning the activity of professional fishermen was therefore raised. To reach this goal, a market survey, investments and fish landings were carried out in order to analyze the profitability and economic performance of this activity. It recorded 5227 catch exits from a sample of 35 fixed fishermen in 7 villages. These were followed 15 times a month for 12 months whenever possible. In practice, approximately 60% of the suspected activity of professional fishermen has been observed. After elaborating the annual operating accounts and calculating the performance ratios, it appears that the lagoon fishing activity of Grand-Lahou is profitable and competitive compared to the alternative economic activities of the study area. However, performance is not homogeneous between villages. This suggests a fishing-related effect on fishers' performance. In addition, it is the Liza falcipinnis and Chrysichthys nigrodigitatus species that significantly influence the value of production and hence income.