In Vitro ​Kelp Crab (​Pugettia producta) ​Embryo in Various Salinities with Comparisons to Embryos Raised ​In Vivo

Abstract

Developing embryos of near-shore marine organisms are subject to freshwater influx, which exposes them to low salinity conditions. This experiment tracked embryo development in kelp crabs (​Pugettia producta​)​ exposed to three salinity treatments [32, 23, and 9 parts per thousand (ppt)]. Data from this experiment indicate that the rate of embryo development is not affected by salinity within the range of 9 – 32 ppt. Survival, determined by presence of heart beats, was highest in 32 ppt. No embryos survived after 24 hours in the 9 ppt. treatment. In addition to salinity testing, rates of embryo development were compared between the embryos cultured in dishes (​in vitro)​ and those allowed to develop in the abdomens of live adult females (in vivo​). The results indicate that embryos develop slightly faster when raised ​in vivo​ rather than ​in vitro​, but that embryos can be reared successfully ​in vitro w​ithout the use of antibiotics.