FRESHWATER SNAIL DIVERSITY IN GROWOUT PONDS OF GIANT GOURAMI REGARDING INTERMEDIATE HOSTS OF TREMATODE LARVAE (CERCARIAE STAGE) IN TIEN GIANG PROVINCE

Nghiên cứu thành phần loài ốc nước ngọt và tỉ lệ nhiễm sán lá song chủ (giai đoạn cercariae) trên ốc trong ao nuôi cá thịt tai tượng ở huyện Châu Thành, tỉnh Tiền Giang được thực hiện vào tháng 10/2020 và tháng 4/2021. Tổng số 4548 mẫu từ 8 loài ốc, 8 giống, 4 họ đã được thu và phân loại dựa theo đặc điểm hình thái. Kết quả cho thấy, ốc Melanoides tuberculata bị nhiễm Xiphidio cercariae và Furcocercous cercariae trong khi ốc Bithynia sp. nhiễm Xiphidio cercariae và Parapleurolophocercous cercariae. Sáu loài ốc còn lại không nhiễm cercariae bao gồm Filopaludina sumatrensis, Pomacea sp., Sermyla tornatella, Sinotaia lithophaga, Tarebia granifera và Thiara scabra. Tỉ lệ ao nhiễm cercariae trong mùa khô cao hơn trong mùa mưa (P>0.05). Cần tiếp tục nghiên cứu dịch tễ học của sán lá song chủ trong ao nuôi cá tai tượng nhằm góp phần phát triển nuôi trồng thủy sản bền vững và an toàn vệ sinh thực phẩm.

Are Freshwater Snails, Melanoides sp. and Invasive Tarebia granifera (Gastropoda: Thiaridae) Suitable Intermediate Hosts for Calicophoron microbothrium (Trematoda: Paramphistomoidea)? An Experimental Study

Prosobranch snails and adult Paramphistomoidea flukes were collected from water bodies and cattle abattoir located in Mpumalanga province of South Africa, respectively. The snails were identified based on morphological characters as well as the ITS-2 and 16S markers as Melanoides sp. and Tarebia granifera, respectively, and the Paramphistomoidea flukes were identified as Calicophoron microbothrium using the ITS-1/5.8S/ITS-2 marker. After confirming identification, the snails were bred to first filial generation (F1) under laboratory conditions. Ninety snails were randomly selected from the laboratory-bred F1 snails and 25 Melanoides sp. and 20 T. granifera were exposed to C. microbothrium miracidia, and the same numbers were maintained as non-exposed controls. Results showed that C. microbothrium successfully established in Melanoides sp. and produced cercariae, and the prepatent period recorded was 21 days. Three snails shed cercariae at day 21 postexposure (PE), and rediae and free cercariae were detected in the soft tissues of one snail on dissection at day 44 PE. The same fluke did not establish in T. granifera. Melanoides sp. started producing offspring at day 7 PE, and T. granifera at day 14 PE. In conclusion, our results showed that Melanoides sp. used in this study is a suitable intermediate host for C. microbothrium under experimental conditions, and given the wide distribution of this snail species, it is important to determine its role in the natural transmission of other Calicophoron species that have been reported in South Africa.

RIESGO EPIDEMIOLÓGICO Y ZOONÓTICO DE LA MALACOFAUNA FLUVIALY TERRESTRE EN EL ÁREA DE SALUD CAPITÁN ROBERTO FLEITES, CUBA

El objetivo fundamental fue identificar el riesgo epidemiológico y zoonótico de la malacofauna fluvial y terrestre en el Área de Salud Roberto Fleites, perteneciente al municipio Santa Clara, provincia Villa Clara, Cuba. Los caracoles fueron muestreados mensualmente durante el 2011- 2012. Las especies de moluscos con mayor frecuencia y distribución fueron: Praticolella griseola, Tarebia granifera y Pseudosuccinea columella. Las especies con mayor interés médico fueron: P. griseola, P. columella, Subulina octona, Physella acuta, Pomacea poeyana y Galba cubensis que son hospederos intermediarios y transmisores de enfermedades parasitarias helmínticas. Se observó una mayor abundancia de moluscos en huertos-organopónicos en relación a los cuerpos de agua muestreados; sin embargo, se obtuvo mayor riqueza de especies de moluscos en los cuerpos de agua que en los huertos-organopónicos. Existe mayor riesgo epidemiológico en huertos-organopónicos, donde el 96,49 % de los moluscos son capaces de transmitir enfermedades al hombre y los animales, mientras que en los cuerpos de agua, solo el 8,32 % de los moluscos son capaces de transmitir enfermedades al hombre y animales. Se evidenció una relación significativa entre las poblaciones de moluscos y la humedad relativa máxima y la precipitación.

Are Melanoides tuberculata and Tarebia granifera (Gastropoda, Thiaridae), suitable first intermediate hosts of Clonorchis sinensis in Vietnam?

Background Two thiarid snail species, Melanoides tuberculata and Tarebia granifera have been reported as first intermediate hosts of the liver fluke Clonorchis sinensis; however, their role as true first intermediate hosts has not been verified. Thus, the present study aimed to clarify the suitability of these two snail species as first intermediate hosts of C. sinensis. This was accomplished by collecting snails from a highly endemic area for C. sinensis in Vietnam, the Thac Ba reservoir, and identifying shed cercariae using molecular techniques. We also conducted experimental infections of five snail species including M. tuberculata and T. granifera with eggs of C. sinensis. Methodology/Principal findings A total of 11,985 snails, representing 10 species were sampled. Five snail species, M. tuberculata, T. granifera, Lymnaea swinhoei, Parafossarulus manchouricus, and Bithynia fuchsiana were found shedding cercariae with an overall prevalence of infection ranging from 0.7% to 11.5%. Seven cercarial types were recorded. Cercariae of C. sinensis were only found in Parafossarulus manchouricus. Using a multiplex PCR approach for detecting C. sinensis infection, the prevalence in P. manchouricus was 4.2%. Additionally, all five snail species were experimentally exposed to C. sinensis eggs, however only P. manchouricus was successfully infected with an infection rate of 7.87%. Conclusions/Significance We confirmed that in the Thac Ba reservoir, Vietnam, the two thiarids, M. tuberculata and T. granifera are not suitable first intermediate hosts of C. sinensis. Only P. manchouricus was found infected by C. sinensis in nature, and was the only species that became infected experimentally.

Invasive Status of Tarebia Granifera Based on Density of Population in River of Gunung Sejuk Village, South Buton Regency

This research was conducted from May to August 2020, located in the Wandoke Watershed, Gunung Sejuk Village, South Buton Regency. This study aims to analyze the invasive status of the alien species Tarebia granifera based on the perspective of its population density in the river of Gunung Sejuk village. This research is intended to examine the dominance of T. granifera species to local gastropod commodities in the typical habitats and niches of the Wandoke river. Determination of the station or location of the observation begins with a preliminary survey, making it easier to select and determine research stations. Determination of research stations using purposive sampling technique or method of designating stations deliberately, based on the presence of invasive alien species populations of T. granifera and T. granifera sampling using simple random sampling or T. granifera sampling is done randomly in a square transect measuring 100 m2 , using a quadratic transect measuring 1 m2, with the assumption that each point in the transect measuring 100 m2 has homogeneous conditions. The population density of T. granifera at each station in the months of May - August (Spatial and Temporal) shows the size is not much different, where the density range is 21 ind/m2- 43.33 ind/m2. The results of measurement and population density analysis of T. granifera in the waters of the Wandoke river, Gunung Sejuk village is the massive empirical evidence of the invasive pattern of the thiaridae snail.

Spatial Distribution of Macrozoobenthos as Bioindicators of Organic Material Pollution in the Citanduy River, Cisayong, Tasikmalaya Region, West Java, Indonesia

The Cisayong area of ​​Tasikmalaya Regency is an area that is passed by the Citanduy River. Citanduy River has received a variety of inputs, that affect the river water quality and cause pollution. Macrozoobenthos can be used as an indicator of water pollution. This research aims to determine the spatial distribution of the macrozoobenthic community as a bioindicator of organic matter pollution in the Citanduy River, Cisayong Tasikmalaya Region, West Java. This research was conducted on January 2 - March 3, 2020. The research method used a field survey method. The data collection technique used purposive sampling by determining 4 stations based on environmental factors and land use around the river flow. The results of the macrozoobenthic spatial distribution along the Citanduy River were different at each observation location. At station 1 several intolerant species Heptagenia sp., Leptophelbia sp., and Hydropsyche sp. Were found, station 2 found several facultative species Melanoides tuberculata, Lymnea sp., Tarebia granifera, Sulcosfira testudinaria, Filopaludina javanica, and Pomacea canalicuta, station 3 found several tolerant species Chironomus sp., and Tubifex sp., station 4 were found several species of facultative and tolerant macrozoobenthos Melanoides tuberculata, Lymnea sp., Tarebia granifera, Sulcosfira testudinaria, Filopaludina javanica, Pomacea canalicuta, and Tubifex sp. The abundance of macrozoobenthos in the Citanduy River ranges from 1460-2540 ind/m2. Diversity index ranges from 1.53 to 1.79. The uniformity index ranges from 0.45 to 0.53. Species deficits at each station are different. The Morisita index ranges from 0.48 to 1.12 representing uniform categories and groups.

Potensi Ekowisata di Bukit Cinta Danau Rawapening Kabupaten Semarang

Indonesia mempunyai berbagai jenis sumberdaya hayati potensial yang dapat dimanfaatkan sebagai objek daya tarik wisata unggul, salah satunya adalah Bukit Cinta Danau Rawapening. Objek wisata tersebut menyajikan landskap alami dan berlokasi di pertemuan Semarang-Solo-Yogyakarta. Potensi sumberdaya dan lokasi yang strategis membuat objek wisata tersebut menjadi salah satu dari 15 danau prioritas nasional, namun demikian masih banyak potensi sumberdaya hayati yang dapat diikembangkan untuk membangun ekowisata di Bukit Cinta Danau Rawapening. Tujuan dari penelitian ini untuk mengidentifikasi sumberdaya biotik terhadap ekowisata dan mengkaji potensi ekowisata di Bukit Cinta Danau Rawapening Kabupaten Semarang. Penelitian ini dilakukan pada bulan September 2018-Maret 2019 dengan mengumpulkan data primer yang meliputi keanekaragaman plankton, makrobenthos, nekton, vegetasi, fisika kimia perairan, potensi objek wisata, dan data sekunder meliputi keanekaragaman burung, jumlah pengunjung. Parameter biotik dianalisis strukturnya sedangkan kualitas air status fisik-kimia. Penilaian potensi daerah wisata menggunakan metode ADO-ODTWA Danau. Berdasarkan hasil penelitian di Bukit Cinta Danau Rawapening dalam aspek biotik memperlihatkan bahwa biota yang mendominasi adalah Melosira sp, Tarebia granifera, Oreochromis niloticus, Eichhornia crassipes, Bubulcus ibis, dan kualitas air masih layak digunakan sebagai tempat wisata. Berdasarkan hasil penilaian identifikasi potensi daerah wisata Bukit Cinta Danau Rawapening termasuk dalam klasifikasi tinggi dengan nilai 6310. Hal ini mengindikasikan bahwa objek wisata Bukit Cinta Danau Rawapening memiliki potensi yang layak untuk dikembangkan menjadi destinasi ekowisata

ASOCIACIÓN DE ALGUNAS VARIABLES CLIMATICAS CON LA FASCIOLOSIS, ANGIOSTRONGILOSIS Y LA MALACOFAUNA FLUVIAL DE LA PROVINCIA VILLA CLARA, CUBA

El objetivo de la investigación estuvo dirigido a determinar la posible incidencia de algunas variables climatológicas sobre las entidades fasciolosis y angiostrongilosis en la provincia Villa Clara, Cuba durante los años 2014 y 2015. Se realizaron seis muestreos por cada año (bimestral) en 329 ecosistemas fluviales de los 13 municipios que conforman la provincia. El método empleado fue el de captura por unidad de esfuerzo durante 15 min. Los moluscos vivos recolectados fueron trasladados al Laboratorio de Malacología Médica de Villa Clara, para su identificación. Se identificaron 21 especies de moluscos; de las cuales, dos se clasificaron como endémica, 12 como locales y siete como introducidas. Las familias mejor representadas y distribuidas resultaron ser Planorbidae, Lymnaeidae y Ampullariidae. Las especies más abundantes y mejor representadas fueron Tarebia granifera, Physella acuta, Galba cubensis y Melanoides tuberculata. Las variables climáticas que mayor incidencia tuvieron sobre la fasciolosis fueron la temperatura media regresada en un bimestre y la precipitación regresada en 4 bimestres, mientras que para la angiostrongilos fue la humedad relativa mínima; para las demás variables no se encontraron correlaciones significativas. Si tenemos en cuenta la elevada riqueza de especies de moluscos de interés sanitario existente en la provincia y la alta incidencia que tienen las varibles climáticas en la fasciolosis y angiostrongilosis, pues es evidente el riesgo potencial que representa para la salud humana y animal de esta provincia la existencia de especies de moluscos con potencialidades para cerrar el ciclo biológico de numerosas especies de tremátodos y nemátodos.

DISTRIBUCIÓN Y ABUNDANCIA DE GASTRÓPODOS FLUVIALES Y TERRESTRES CON VARIABLES METEOROLÓGICAS MEDIANTE LA MODELACIÓN MATEMÁTICA. SANTA CLARA, VILLA CLARA, CUBA

Los moluscos son en apariencia, anatomía, fisiología y ecología un grupo altamente diverso y representa el segundo mayor grupo de invertebrados. El objetivo del presente trabajo consistió en confeccionar un modelo matemático en función de variables meteorológicas, que permita predecir la distribución y abundancia de los gasterópodos fluviales y terrestres en el municipio Santa Clara, Cuba. Para ello se analizaron las cinco áreas de salud del municipio, en el período comprendido entre marzo y julio del 2019. Se colectaron especímenes en los ecosistemas con uso humano de estas áreas de salud, así como datos meteorológicos de la estación que mantiene vigilancia sobre ellas. En el desarrollo del modelo predictivo se empleó la Modelación Objetiva Regresiva (ROR). El área de salud con una mayor abundancia y diversidad de gasterópodos fue Capitán Roberto Fleites, la especie fluvial con una mayor distribución resultó ser Physella acuta (Draparnaud, 1805) y la más abundante, Tarebia granifera (Lamarck, 1816). En el caso de las especies terrestres ambos valores correspondieron a Praticolella griseola (Pfeiffer, 1841). Las variables meteorológicas con mayor influencia sobre los gasterópodos fueron las temperaturas y las precipitaciones; a medida que estas aumentan, disminuyen las cantidades de gasterópodos. El modelo de predicción introdujo a la temperatura mínima y la humedad relativa mínima como variables directamente proporcionales a la cantidad de gasterópodos; por otra parte, introdujo a la precipitación y la presión atmosférica como variables inversamente proporcionales. La influencia predicha del anticiclón del Atlántico resultó ser inversamente proporcional a la cantidad de gasterópodos esperada.