Effects of macroalgae Chaetomorpha sp.on the cultivations of calanoid copepod Pseudodiaptomus ishigakiensis
Jr Siang, Yang
940478jason@gmail.com
Department of Aquaculture, National Taiwan Ocean University, Keelung City, Taiwan (R.O.C)
Copepod is potential live feed in marine larviculture industry. It has competitive nutritional advantages for fish and crustacean larvae when compared to artemia and rotifer. However, the difficulty in mass culture and the risk of pathogen transmission from copepod have created a barrier to their extensive application in larval feeding. One of the approaches for producing copepod with reduced pathogen load could be the co-cultivation with anti-pathogenic macroalgae. The branches of macroalgae could increase copepod habitat surface as well as inhibit the growth of pathogen. This study aims to investigate the effects of macroalgae co-cultivation (Chaetomorpha sp.) and their water extract on the population growth and bacterial load of calanoid copepod Pseudodiaptomus ishigakiensis. Copepods were cultivated in different treatments: co-cultivations with Chaetomorpha sp. branches (10 g/L, 20 g/L and 30 g/L) or additions of macroalgae water extract (2.5%, 5% and 10% extract stock solution: 5 g of branches grinded in 100 mL sterile seawater). The result indicates that 10 g/L co-cultivation and 2.5% water extraction treatments had notably increasing copepod population growth rate and decreasing bacterial load among all treatments. Our preliminary findings have demonstrated the feasibility of using macroalgae co-cultivation and water extract to improve the quantity and quality of copepod production in laboratory condition, mass production trials will be carried out to verify their applicability at industrial scale.
Keywords: copepod, macroalgae, co-cultivation, population growth, bacterial load
