Identification of trichodinids (Ciliophora: Trichodinidae) from red tilapia (Oreochromis niloticus x O. mossambicus) in Pathumthani Province, Thailand

Abstract

Trichodinid ciliates are well-known pathogenic in aquacultures. This study aimed to identify trichodinid species isolated from red tilapia (Oreochromis niloticus x O. mossambicus). Ninety red tilapia (40-152 [mean ± SD: 69.5 ± 26.4] mm) were monthly collected from an earthen pond in Nong Suea Prefecture, Pathumthani Province, Thailand by scoop net. The mucous smear and wet smear of gills were prepared for trichodinid examination. Klein’s silver-impregnation technique was used for the morphological study of trichodinid specimens. Three species of trichodinids (i.e., Trichodina heterodentata, T. centrostrigeata and T. compacta) were isolated and described in this research. Our result revealed the new host and locality record in Thailand. Additionally, the characteristics of these three species are documented based on Thai specimens for the first time.