Avaliação da presença de Achatina fulica Bowdich, 1822 (Gastropoda: Pulmonata) em Feira de Santana, Bahia, e estudo de parasitos associados

Abstract

The African snail Achatina fulica Bowdich, 1822, is an invasive species that cause environmental and economic damage, as to human and animal health. The aim of this study was to evaluate the occurrence and parasitological aspects of A. fulica in Feira de Santana (BA). To assess the occurrence of A. fulica, sampling was made from January to June 2013 at four points in the urban perimeter of the city. In the laboratory animals were measured as the total length of the shell and the total mass. From these data the degree of development of the population was estimated, and the relationships between morphometric and climatic variables and the condition factor were calculated. During this period were collected 600 snails showing predominant length in the range of 57.0 to 47.6 mm. Results allowed to infer that the population of A. fulica in these sampling points is in decline, since in these areas were found juvenile and young animals. There was no association between climatic and morphometric variables. The relationship between total length and weight showed that A. fulica presented a negative allometric growth. The condition factor presented variations on time over the six months of collection. In order to evaluate parasitological aspects in A. fulica, animals were collected from may 2012-to june 2013 in eight areas in the urban perimeter of the city.The animals were collected early in the morning and transported to the laboratory of the Zoonoses and Public Health Research Group -UEFS. Each clam was analyzed individually using the artificial digestion technique in hydrochloric acid solution with identification of larvae found. The larvae have been identified as Metastrongylidae were submitted to the polymerase chain reaction for the identification of the genus Angyostrongylus. 220 animals were tested and in 28 (12.7; 95: 8.6 -17.9) were found at least one of four morphotypes of nematodes. Angyostrongylus has not been registered in snails examined. There was no association between climatic variables and the presence of larvae. The location of collection and the size of the snail influenced in the larvae of nematodes. Both parasited and not parasitised animals have negative allometric growth. The relative condition factor did not differ significantly between the groups. Nested-PCR has been used to search Cryptosporidium ssp and Sarcocystidae DNA in fecal samples of Achatina fulica. Amplicons compatibles with Cryptosporidium ssp were found in 2 of 223 stool samples analyzed. Of the 223 stool samples analysed, in 58 samples we found the 290 base pair fragment expected for Sarcocystidae, and then subjected to RFLP. Of these, 41 samples were cleaved by enzymes used in this study, producing a profile compatible with T. gondii. The other 17 samples were not compatible with Sarcocystidae. This is the first record of the occurrence of A. fulica in Feira de Santana (BA), with research of association of climatic variables to the biometric parameters of the animals. These results indicate the presence of animal and humana parasites in Achatina fulica in the municipality of Feira de Santana, demonstrating the potential of these animals in the maintenance and spread of these agents in the environment.