SURVEY OF HELMINTHS IN CLIMBING PERCH (ANABAS TESTUDINEUS) FROM SAN SAI DISTRICT, CHIANG MAI PROVINCE

Abstract. A helminthological study of Anabas testudineus was conducted. Fifty fish were collected from natural water resources in San Sai District, Chiang Mai Province, between July and September 2003. Seven species of helminths were recovered, as follows; one Monogenea species, Trianchoratus sp, was recovered at gill filaments, with a prevalence of 32%. In the intestine, the adult stage Acanthocephala, nematodes, and trematodes were found: Pallisentis sp (22%), Camallanus sp (11%), and Allocreadium sp (2%), respectively. Moreover, metacercarial stages of three species: Stellantchasmus falcatus (88%), Acanthostomum sp (78%), and Centrocestus caninus (70%), were examined in the body portion of the fish (gills, fins, scales, head, and muscles). Two species of metacercarial stage, Centrocestus caninus and Stellantchasmus falcatus, are helminths that can infect humans. plates, and then examined under a compound microscope. The intestine was dissected by needles and the presence of worms was determined using a stereomicroscope. The head and muscles were chopped and digested with crude extract solution of pineapple in a blender. Sequentially, the mixture was transferred into Erlenmeyer flasks, then incubated in a shaking water bath at 37˚C for 2 hours. The metacercariae were isolated using graded sieves and then rinsed with 0.85% sodium chloride solution. The encysted metacercariae were studied and identified with excysted metacercariae under a compound microscope. All of the worms were fixed in 5% formalin, stained with hematoxylin or borax carmine, dehydrated in alcohol series, and mounted with permount. Species identification was carried out by morphological examination, as described by RESULTS Out of 50 climbing perch (Anabas testudineus) collected from natural water sources in San Sai District, 49 were infected with 7 species of helminths. The species with the highest infection rate was Stellantchasmus falcatus (88%) while Acanthostomum sp, Centrocestus caninus, Camallanus sp, Trianchoratus sp, and Pallisentis sp were present in 78, 70, 66, 32, and 22%, respectively. The species with the lowest infection rate was Allocreadium sp (2%), as shown in The result revealed that S. falcatus showed the highest mean intensity, at 59.64 (2,982/50), while Acanthostomum sp and C. caninus were 41 (2,092/50) and 40.82 (2,041/50), respectively. In contrast, the adult stage of the trematode, Allocreadium sp, wa

High prevalence of Haplorchis taichui metacercariae in cyprinoid fish from Chiang Mai Province, Thailand

This study aimed to investigate Haplorchis taichui metacercarial infection in fish collected from the Chom Thong and Mae Taeng districts, Chiang Mai Province during November 2001 to October 2002. A total 617 cyprinoid fish of 15 species were randomly collected and examined for H. taichui metacercariae. All the species of fish were found to be infected with H. taichui. The infection rates were 91.4% (266/290) and 83.8% (274/327), with mean intensities of 242.9 and 107.4 in the Chom Thong and Mae Taeng districts, respectively. The portion of the fish body with the highest metacercarial density was the muscles, and second, the head, in both districts. In addition, the fish had mixed-infection with other species of trematodes, namely: Centrocestus caninus, Haplorchoides sp, and Haplorchis pumilio

High prevalence of Haplorchis taichui metacercariae in cyprinoid fish from Chiang Mai Province, Thailand

This study aimed to investigate Haplorchis taichui metacercarial infection in fish collected from the Chom Thong and Mae Taeng districts, Chiang Mai Province during November 2001 to October 2002. A total 617 cyprinoid fish of 15 species were randomly collected and examined for H. taichui metacercariae. All the species of fish were found to be infected with H. taichui. The infection rates were 91.4% (266/290) and 83.8% (274/327), with mean intensities of 242.9 and 107.4 in the Chom Thong and Mae Taeng districts, respectively. The portion of the fish body with the highest metacercarial density was the muscles, and second, the head, in both districts. In addition, the fish had mixed-infection with other species of trematodes, namely: Centrocestus caninus, Haplorchoides sp, and Haplorchis pumilio