Gracienhe Gomes Santos

Bio: Gracienhe Gomes Santos is an academic researcher from Empresa Brasileira de Pesquisa Agropecuária. The author has contributed to research in topics: Species richness & Fish farming. The author has an hindex of 3, co-authored 8 publications receiving 52 citations.

Albendazole, levamisole and ivermectin are effective against monogeneans of Colossoma macropomum (Pisces: Serrasalmidae).

Abstract: This study evaluated the efficacy of albendazole, ivermectin, levamisole, mebendazole and praziquantel on monogeneans of Colossoma macropomum, based on in vitro and in vivo assays. In vitro assays indicated that albendazole (500, 100, 1,500 and 2,000 mg/L), ivermectin (200, 250, 300 and 350 mg/L) and levamisole (50, 75, 100 and 125 mg/L) were 100% effective against Anacanthorus spatulatus, Notozothecium janauachensis, Mymarothecium boegeri and Linguadactyloides brinkmanni, while mebendazole (125, 150, 175 and 200 mg/L) and praziquantel (5, 10, 15 and 20 mg/L) were ineffective. Fish mortality in 24 hr therapeutic baths with 500 mg/L of albendazole was 6.6%, but the behaviour of the animals remained unchanged, while 200 mg/L of ivermectin caused lethargy, signs of hypoxia and 100% mortality within 2 hr, and 125 mg/L of levamisole caused no mortality. The efficacy of 500 mg/L of albendazole was 48.6% in the 24 hr baths, while that of 125 mg/L levamisole was 88.2%. Although ivermectin showed in vitro efficacy, the lowest concentration used in baths was highly toxic to fish. Therefore, we recommend the use of 125 mg/L of levamisole to control and treat monogenean infestations on C. macropomum in fish farming.

Diversity of metazoan parasites in Colossoma macropomum (Serrasalmidae) from the lower Jari River, a tributary of the Amazonas River in Brazil

Abstract: This study investigated the diversity of metazoan parasites in Colossoma macropomum from the Jari River, in the eastern Amazon, northern Brazil. We collected a total of 4966 parasites from 34 fishes, including monogeneans (Anacanthorus spathulatus, Mymarothecium boegeri, Notozothecium janauachensis and Linguadactyloides brinkmanni), nematodes (Spectatus spectatus larvae, Contracaecum sp. larvae andProcamallanus (Spirocamallanus) inopinatus), digeneans (Cladorchiidae metacercariae), acanthocephalans (Neoechinorhynchus buttnerae), crustaceans (Ergasilus turucuyus, Argulus multicolor, Perulernaea gamitanae and Braga patagonica), mites and leeches. The dominance was of monogenean species, found in the gills of the hosts. The parasites exhibited high aggregate dispersion, except Contracaecum sp. and P. (S.) inopinatus, that showed uniform and random dispersion, respectively. The species richness of parasites varied from 1 to 9, the Brillouin diversity index from 0 to 1.52, evenness from 0 to 0.63 and the Berger-Parker dominance index from 0.39 to 1.00. Abundance of parasites was not influenced by host length, but there was significant correlation with host body weight in some cases. The parasite community was characterized by low species richness and moderate diversity, with a predominance of ectoparasites with high prevalence and abundance, as well as the presence of endoparasites in the larval stage.

Parasite fauna of tambaqui reared in net-cages at two stocking densities

Abstract: This study investigated the parasite fauna in Colossoma macropomum reared at two stocking densities in net-cages of a fish farm in the Matapi River, State of Amapa. Before stocking fish in the net-cages for fattening, fish were examined for parasites and also at the end of 90 and 180 days at densities of 50 and 100 fish m-3, respectively. All fish were parasitized by one or more species such as Ichthyophthirius multifiliis, Piscinoodinium pillulare, Anacanthorus spathulatus, Mymarothecium boegeri, Notozothecium janauachensis, Procamallanus (Spirocamallanus) inopinatus and Acarina gen. sp., but the dominance was of I. multifiliis. Parasites presented aggregated dispersion pattern, and there were no differences in the fish relative condition factor between the densities used. There was positive correlation of I. multifiliis abundance and monogenean abundance with length and weight of the hosts. Before fish stocking, the mean intensity and mean abundance of I. multifiliis, A. spathulatus and M. boegeri were lowest when comparing fish at densities of 50 and 100 fish m-3, which were similar to each other. The mean intensity and mean abundance of N. janauachensis was highest in the density of 50 fish m-3 when comparing the fish before stocking and at a density of 100 fish m-³. The mean abundance of P. (S.) inopinatus was highest in fish kept at 100 fish m-3 when compared to fish before stocking and 50 fish m-3. However, P. pillulare and mites occurred only in density of 50 fish m-3. There was a predominance of ectoparasites and few endoparasites, as expected. Therefore, it is necessary the constant monitoring of the parasites, to better implement control strategies aiming to avoid the occurrence of diseases.

Parasites in Loricariidae from Brazil: checklist and new records for fish from the Brazilian Amazon

Abstract: The aim of this study was to investigate the parasites fauna of Ancistrus leucostictus , Hypostomus ventromaculatus , Ancistrus sp. and Hemiancistrus sp. from the Igarape Fortaleza River (Amapa State, Brazil), besides making a checklist of the parasite species in Loricariidae from Brazil. A total of 53 fishes were collected from November 2013 to August 2014. In the hosts, a total of 1,559 parasites of seven taxa were collected: Unilatus unilatus , Trinigyrus mourei , undetermined metacercariae, Genarchella gernachella , Raphidascaris ( Sprentascaris ) sp., Gorythocephalus elongorchis and Proteocephalus sp. Ectoparasite species were frequent in the examined Loricariidae species, which also had larval stages of endoparasites. The hosts with the highest sampled number, H. ventromaculatus and Ancistrus sp., had the highest parasite species richness. Loricariidae species from Brazil are parasitized by species of Protozoa, Monogenea, Nematoda, Digenea, Acantocephala, Cestoda, Crustacea and Hirudinea, but monogeneans, digeneans and nematodes were the predominant taxa.

A new species

Abstract: We redescribe the only previously known species of Myrsidea from bulbuls, M. pycnonoti Eichler. Sixteen new species are described; they and their type hosts are: M. phillipsi ex Pycnonotus goiavier goiavier (Scopoli), M. gieferi ex P. goiavier suluensis Mearns, M. kulpai ex P. flavescens Blyth, M. finlaysoni ex P. finlaysoni Strickland, M. kathleenae ex P. cafer (L.), M. warwicki ex Ixos philippinus (J. R. Forster), M. mcclurei ex Microscelis amaurotis (Temminck), M. zeylanici ex P. zeylanicus (Gmelin), M. plumosi ex P. plumosus Blyth, M. eutiloti ex P. eutilotus (Jardine and Selby), M. adamsae ex P. urostictus (Salvadori), M. ochracei ex Criniger ochraceus F. Moore, M. borbonici ex Hypsipetes borbonicus (J. R. Forster), M. johnsoni ex P. atriceps (Temminck), M. palmai ex C. ochraceus, and M. claytoni ex P. eutilotus. A key is provided for the identification of these 17 species.

Antiparasitic and Antibacterial Functionality of Essential Oils: An Alternative Approach for Sustainable Aquaculture.

Abstract: Using synthetic antibiotics/chemicals for infectious bacterial pathogens and parasitic disease control causes beneficial microbial killing, produces multi-drug resistant pathogens, and residual antibiotic impacts in humans are the major threats to aquaculture sustainability. Applications of herbal products to combat microbial and parasitic diseases are considered as alternative approaches for sustainable aquaculture. Essential oils (EOs) are the secondary metabolites of medicinal plants that possess bioactive compounds like terpens, terpenoids, phenylpropenes, and isothiocyanates with synergistic relationship among these compounds. The hydrophobic compounds of EOs can penetrate the bacterial and parasitic cells and cause cell deformities and organelles dysfunctions. Dietary supplementation of EOs also modulate growth, immunity, and infectious disease resistance in aquatic organisms. Published research reports also demonstrated EOs effectiveness against Ichthyophthirius multifiliis, Gyrodactylus sp., Euclinostomum heterostomum, and other parasites both in vivo and in vitro. Moreover, different infectious fish pathogenic bacteria like Aeromonas salmonicida, Vibrio harveyi, and Streptococcus agalactiae destruction was confirmed by plant originated EOs. However, no research was conducted to confirm the mechanism of action or pathway identification of EOs to combat aquatic parasites and disease-causing microbes. This review aims to explore the effectiveness of EOs against fish parasites and pathogenic bacteria as an environment-friendly phytotherapeutic in the aquaculture industry. Moreover, research gaps and future approaches to use EOs for sustainable aquaculture practice are also postulated.