Ingeniero

Solo disponible en BuenasTareas
  • Páginas : 19 (4640 palabras )
  • Descarga(s) : 0
  • Publicado : 3 de junio de 2011
Leer documento completo
Vista previa del texto
North Central Regional Aquaculture Center
In cooperation with USDA

Trout Culture in the North Central Region
by K. Cain and D. Garling, Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI

Introduction
Trout have been raised in the United States for about 150 years. Initially, trout were raised to replace wild stocks that were declining because of overfishing, loss of habitat and pollution. United States trout farming began in the North Central Region with the establishment of Ackley’s Farm near Cleveland, OH. This farm was run by Theodatus Garlick, M.D., and H.A. Ackley, M.D., who developed ways to spawn brook trout and incubate the eggs in glass jars. Today, trout are still raised in the North Central Region in state, federal and private fish farmsto stock lakes, ponds and streams. Trout are also raised and sold through fee fishing operations and as food fish through restaurants and supermarkets. Rainbow trout are the most commonly raised trout followed by brook and brown trout. Private commercial trout farms range from small owner/operator farms to large farms with many employees. The states of Michigan, Wisconsin, and Missouri had atotal of 114 trout farms which had a combined total sales of approximately 6.8 million dollars in 1991. Further expansion of trout farming in the region is constrained by the scarcity of adequate supplies of high quality water at appropriate temperatures. The information in this fact sheet is intended to provide an overview of basic trout culture practices used in the region. Water quantity andquality are discussed along with hatchery design, spawning and rearing, incubation, production, feeding, general fish health management and marketing. This material can be applied to any size fish culture operation. Additional information on state permits, regulations, business planning, finance, and economic data will be necessary to plan and start a successful trout farm.

while flows exceeding2,000 gpm are commonly used at large commercial operations. Smaller water flows are required for fee-fishing operations, however at least 50 to 100 gpm is still desirable.

Water Quality
In addition to abundant quantity, high quality water is essential for a commercial trout hatchery. Dissolved oxygen, tempera ture, suspended solids, dissolved gasses, pH, mineral content, hardness, andalkalinity of the water supply should be analyzed before any site specific facility plans are initiated to assure that they are in the desirable range for trout production (Table 1). If any types of ground water contamination are known to occur in the area, the water should also be tested for those specific toxic chemicals. Potential water sources for a hatchery site should be observed throughout a fullseason. Water temperature is usually the most critical water quality factor. Temperature effects survival, growth and egg production (Table 2). The most desirable water supplies provide water temperatures within the optimum growth range year round. Trout hatcheries should have an adequate supply of high quality water that ranges from about 45-65˚F. Water supplies with temperatures that are outsidethe range for optimum growth for significant periods of time during the

Water Quantity
Before any plans to begin a commercial trout farm are initiated, a thorough study of the water supply should be completed. Trout can be raised in areas where a constant supply of high quality water is available year round. Most trout farms and hatcheries use springs, wells, or streams as the source of theirwater. Production of foodsized fish requires the largest volumes of water. Water flows of at least 500 gallons per minute (gpm) are needed for small operations,

North Central Regional Aquaculture Center Fact Sheet Series #108
USDA grant # 88-38500-4319

April 1993
1

Since trout require high levels of oxygen, the oxygen content Dissolved oxygen 5 ppm to saturation of the water supply...
tracking img