Shrimp Thrive on Sugarcane Waste and Cassava Byproducts

A new sugarcane-based food for shrimp may allow small fish farmers in Hawaii and other tropical areas to participate in the lucrative shrimp industry. Donald W. Freeman of the Agricultural Research Service's Tropical Aquaculture Research unit, and scientists from the Oceanic Institute in Hawaii, developed and tested the new shrimp food. The experimental pellets are made from inexpensive forms of protein, fats, minerals, and bagasse; the crushed stalks that remain after sugarcane is processed.

Results from a 12-week experiment indicate that young, pond-raised marine shrimp grow well on the pellets. Penaeus vannamei, a shrimp species of considerable market value was used in the experiment. Growth of the bagasse-fed shrimp was comparable to that of shrimp in similar sized ponds and fed low-cost commercial feed. The shrimp eat not only the decomposing fibers of the bagasse pellets, but also the bacteria, algae, and microscopic zoo-plankton whose populations increased after the introduction of the pellet. Pellets that sink to the bottom of the pond provide an additional food source as well as new surfaces for the tiny pond creatures to attach to. The experimental pellets cost only $100 a ton-- less than one third the cost of commercial feed that gives comparable results. Small-scale fish farmers in Hawaii, the Virgin Islands, Puerto Rico, and other tropical areas where sugarcane is grown "might be able to raise shrimp economically by feeding them bagasse pellets," Freeman says.

The bagasse-based pellets are not intended for high-yielding, intensive fish farming. The pellets may be best suited for semi-intensive fish farming, in which a moderate number of shrimp are raised in low-cost, saltwater-filled earthen ponds. The nutritious microorganisms that usually augment the shrimp diet, can not survive the overcrouded conditions of intensive shrimp farming. The bagasse pellets, with their lower nutrient content could not sustain intensive shrimp farming. An alternative source of nutrients for pond microorganisms is dried feedlot manure. While it costs about the same as bagasse pellets, it has what Freeman describes as "image problems."

Researchers at the Oceanic Institute continue to look for other ways of improving low cost shrimp food. Chhorn E. Lim, leader of the Tropical Aquaculture Research unit, along with other scientists at Makapuu Point, are working to develop an inexpensive soy-bean-based formula with the balance of nutrients shrimp require. Soybeans are rich in protein, are readily available, and may be able to partially replace squid, fish meal, and other more expensive ingredients in the best quality shrimp feeds.

Advances in Shrimp Farming in Ecuador

Cassava production has contributed greatly to the now booming business shrimp farming in Ecuador. New ways to process the root utilize its high content of elongated starch granules, the origin of its sticking properties. Cassava may replace the imported and reportedly toxic commercial agglutinants.

The shrimp farm technology is changing what had been principally a subsistence crop into a key component of an international food marketing industry. Shrimp growers cannot get enough cassava to fill production needs.

In response to the expanding market for cassava, farmer associations are springing up. There are presently 20 farmer associations with around 400 members. UAPPY, the Unión de Asociaciones de Productores y Procesadores de Yuca, is the union of the small farmer associations involved with the production, transportation, and marketing of the processed cassava. UAPPY markets the cassava and retains 30% of the profits for future cooperative expansion. The organization gives its members leverage in business transactions. One shrimp feed producer describes the UAPPY people as "shrewd businessmen".

The demand for cassava has increased, not only from the growing shrimp industry, but also from consumer demand for the conveniently packaged cassava. The technology, developed by Centro Internacional de Agricultura Tropical (CIAT) was created to preserve cassava root for fish feed.

For further information:

Donald W. Freeman
A.B. McKay Food Laboratory
Mississippi State, MS 39762
(601) 325-3200

Chhorn E. Lim
Tropical Aquaculture Research Unit
Oceanic Institute, Makapuu Point
Waimanalo, Hawaii 96795