Host Fish Suitability for Freshwater Bivalve Anodonta woodiana Breeding Programs

Abstract

The freshwater bivalve Anodonta woodiana is native to China and widely distributed in Asia, Europe, and North America. However, natural populations of A. woodiana in China have dramatically declined recently. Several fish species have been used as potential hosts in breeding programs; nonetheless, the optimal host species is yet to be identified. In this study, we examined the suitability of five potential host fish species (bighead carp, common carp, crucian carp, yellow catfish, and tilapia) for A. woodiana under laboratory conditions. No significant difference was found in the number of glochidia attached to the five fish species; however, tilapia hosted more transformed juveniles than bighead carp, common carp, or yellow catfish (p < 0.05), with bighead carp hosting the least (p < 0.05). Yellow catfish had the highest host capacity index (the number of successfully transformed juveniles/the weight of the host fish × the survival rate of the host fish), 133 times higher than bighead carp and 1.3–2.9 times higher than the other species. The shell length and height of freshly transformed juveniles from yellow catfish were significantly larger than those of other host fish (p < 0.05). The juvenile index (shell length × shell height) of yellow catfish was significantly higher than that of other fish species (p < 0.05). In conclusion, yellow catfish appears to be the most suitable host fish out of the five species tested here.