The demand for shrimp is great in the international and local markets. However, an inadequate supply of natural food for shrimps presents a stumbling block to increased grow-out production.
Through the years, aquaculture scientists have sought for ways to improve the supply of natural food in the hatchery production of shrimps. Such is the motivation behind the development of a new technique in shrimp hatchery operations and management by Dr. Jesse D. Ronquillo of the College of Fisheries, UP Visayas, Dr. Toshio Saisho and Shigehisa Yamasaki of the Fisheries, Kagoshima University.
The foremost objective of the study was to determine the best conditions to culture algae inexpensively and subsequently evaluate the efficiency of this alga as live feed for different species of shrimps from the Indo-West Pacific region. Furthermore, it aimed to determine the effects of different concentrations of organic and inorganic media-such as vitamins and trace metals on food. The dietary value of algae was determined by feeding to different shrimp larvae.
Results of this study reveal that a cheaper natural diet of phytoplankton is beneficial to shrimps. Algae (Tetraselmis tetrathele) were found to be a good alternative to artificial diets and expensive zooplankters. Algae have a high nutritional value and are easy to culture. In fact, algae, a four-flagellated prasinophyte, is currently used as direct live feed in both temperate and tropical regions. It can tolerate various adverse environmental conditions due to its eurythermal and euryhaline characteristics.
This technique, according to Dr. Ronquillo could boost the production of healthy shrimp seedlings and inavariably reduce hatchery operational costs and reap profits for the shrimp industry.
For more information contact Dr. Jesse Ronquillo of the Institute of Aquaculture, College of Fisheries, University of the Philippines in the Visayas, Miag-ao, Iloilo or call at tel. no. 033-3158324 or 513826.
source: Rita T. dela Cruz of www.bar.gov.ph