preview

Yellow Starch Experiment

Decent Essays
Yellow perch fingerlings were raised from 2-day old larvae to 1 g size in an indoor recirculating hatchery system, and then transferred to a nursery recirculation system were they were further raised to the average size of 16.5 g. For the purpose of this study, a total of 6000 fish were divided twice, into two, and then into four separate tank units. Each experimental replication consisted of two identical tank units, each stocked with 1500 fish. The growth of both replicates was monitored until the fish reached a market size of 160 g. Fish were raised at constant temperature of 24-25oC. Dissolved oxygen level was maintained at saturation using oxygen injection. Calcium hardness was maintained between 80-150 mg/l using calcium chloride, and pH was maintained between 7.2 and 7.4 with the addition of sodium bicarbonate.…show more content…
Chlorides, calcium hardness, total hardness, carbon dioxide, alkalinity and salinity were measured weekly. Chlorides were adjusted to 300 - 400 ppm using sodium chloride and calcium chloride, calcium hardness was maintained between 80-150 mg/l using calcium chloride. During the entire experimental period perch were fed continuously with commercial slow sinking pelletized feed (“Ziegler Brothers”, PA), contained 45% of crude protein and 12% fat, using automatic belt feeders. Fish were fed 5% of the body weight per day in the first month, 4% in the second, 3% in the third and fourth, 2.5% in the fifth and sixth month, and 1.5% in the last four months of the growing period (Jug-Dujakovic and Van Gorder,
Get Access