Molecular detection of Chlamydia spp. and risk factors in farmed siamese crocodile in the mid-northeastern provincial cluster of Thailand

This study surveyed the prevalence of chlamydial infection among farms in the mid-northeastern provincial cluster of Thailand by PCR and phylogenetic analyses of the sequences. Samples from 94 crocodiles were collected from 17 farms in five provinces together with farm management data. Chlamydiaceae was found in 48.94% of the samples (46/94). Of the 17 pooled samples analyzed using 16S rRNA sequencing, four samples exhibited 99.3 to 99.5% nucleotide identity with Chlamydia psittaci, three samples exhibited 99.1 to 99.3% nucleotide identity with C. crocodili, and one sample exhibited similarity to both species. The risk factors related to chlamydial infection included the source of young crocodiles and the frequency of water changes. Chlamydial infection was higher in nonclinical crocodiles than in clinical or dead crocodiles (P=0.003). Pharyngitis, fibrinous pharyngitis, hepatitis, pneumonia, and hydropericardium were commonly found in chlamydial-positive cases of ill or dead crocodiles. C. psittaci and C. crocodili were found in both clinical and nonclinical crocodiles. C. psittaci is a well-known zoonotic pathogen. C. crocodili is a new species found in Siamese crocodiles in Thailand. In conclusion, the source of young crocodiles and frequency of water changes were identified as risk factors for chlamydial infection in crocodile farms. C. crocodili should be further investigated to better understand its implications for crocodile heath

In vitro antifungal activity of Cassia fistula L. against selected pathogenic water molds

Water mold infections in both cultured and wild aquatic animals, caused by members of the genera Saprolegnia, Achlya, and Aphanomyces, have widely occurred worldwide.  Outbreaks in aquatic creatures, especially in aquacultural facilities and fish hatcheries are common problem. Cassia fistula L. has been used as medicinal plant for broad purposes including for fungal infectious diseases remedy, but efficacy against water molds is still not apparently known. The present study was aimed to investigate in vitro antifungal activity of C. fistula stem-bark alcoholic extracts against the selected pathogenic water molds isolated from fish. The results showed that the C. fistula extract was capable to kill hyphae and zoospores of Saprolegnia paracitica NJM 8604 and S. diclina NJM 0005 at levels ranging from 1,000-4,000 microg/mL evidently within 24 h-exposure, while, a level of 500 microg/mL was sufficient to kill the both stages of Aphanomyces invadans NJM 9701. In addition, the antifungal activity of C. fistula absolute alcoholic extract comparing to 50% aqueous alcoholic extract were seemingly not different. Conclusively, the C. fistula stem-bark extracts, both absolute and 50% aqueous alcoholic extractions, were effectively able to inhibit growth and kill the 3 strains of pathogenic water molds by affect throughout the 2 important, zoospore and hyphal, stages