Using ultrasonography method for monitoring ovarian status in freshwater stingray (Potamotrygon sp.)

Freshwater stingray is one of the ornamental fish trade in Thailand. The information of reproductive management has been limited. No studies have been carried out on ovarian status. Therefore, the main objective of this study was to apply and develop techniques for monitoring ovarian status in freshwater stingray by using ultrasonography. The ovarian fecundity varied among species and only the left ovary seemed to be functional. The stingrays were placed in fitted tank with water in ventral recumbency position. The imaging was done in B-mode. The suitable frequency was 6.5 MHz, covered all size of mature female stingrays. There was no statistically significant relationship between body depth and ovarian size (p>0.05). In the TLV view, it was easy to manipulate and differentiate type and appearance of follicles or corpora lutea, meanwhile in the LDV view, estimate amount of the structures can be provided.