Evaluation of three commercial diets in relation to offspring quality for the culture of the ornamental shrimp "red cherry" Neocaridina davidi

LÓPEZ GRECO, LAURA SUSANA; SGANGA, DANIELA ELIANA

Jornada; IX JORNADAS DE JÓVENES INVESTIGADORES FVET; 2019

Neocaridina davidi is a popular freshwater ornamental species traded worldwide for aquarium keeping. Its culture generally relies on commercially available feeds. Diet composition and nutritional value often affect offspring quality, because crustacean embryos and lecitotrophic larvae or juveniles depend exclusively on the nutrients present in egg yolk which is provided by females. The aim of this study was to evaluate three commercial diets for the culture of N. davidi, in terms of offspring quality. One female and two males of the same age were randomly assigned to each replica and fed 7% with one of the following commercial diets: TetraColor® (Tetra, Melle, Germany), Crusta Sticks® (Tropical, Chorzów, Poland), Basic® (Labcon, Camboriú, Brazil). Immediately after hatching, a random sample of 5 to 10 juveniles I (JI) from each brood was photographed to quantify the area of the perigastric organ occupied by lipid droplets, and weighed. Another random sample of 12 JI from each brood was subjected to a food restriction test, which lasted 32 days. Each JI was placed in a plastic container and maintained under the same conditions than brooders. JI were assigned to the same diet treatment as their parents and to one of the following restriction treatments: daily feeding during the 32-day period or food deprivation for the initial 8 post-hatching days and then daily feeding until day 32. Mortality was checked daily throughout the test and surviving 32-day-old shrimps were weighed. Juvenile I weight was similar for all diets. However, the amount of lipid droplets found in the perigastric organ region in Juveniles I from brooders fed Crusta Sticks®, was about 20 % lower than that from brooders fed TetraColor® or Basic®. Even though offspring survival to the food restriction test was similar for all diets, the weight of 32-day-old juveniles was lower when brooders were fed Basic® diet.