Environmental Resources Unit C Animal Wildlife Management

Problem Area 3 Fish Management

Describing nutritional requirements of fish Lesson 3

Describing nutritional requirements of fish From the nutritional labels provided: –Write amount of fat, carbohydrates, proteins, and vitamins. What types of foods provide us with the different nutrients? How does fish receive these nutrients?

Terms Amino acid Blood meal Carbohydrates Carnivore Fat-soluble vitamins Fats Fish meal Herbivore Minerals Omnivore Protein Soybean meal Trace elements Vitamins Water-soluble vitamins

Objectives Describe the role of protein in fish nutrition. Describe the role of fats in fish nutrition. Describe the role of carbohydrates in fish nutrition. Describe the role of minerals in fish nutrition. Describe the role of vitamins in fish nutrition.

What is the role of protein in fish nutrition? First major component required for proper nutrition of fish is protein. Protein –Formed from compounds known as amino acids. ag.arizona.edu/aes/mac/catfish.htm

What is the role of protein in fish nutrition? Amino acids –Building blocks of protein. –Needed by animals for proper nutrition. –10 amino acids are essential. –Broken down during digestion. –Used to produce new tissue or reproduce damaged tissue.

Protein Most critical component of fish feed. Prepared fish feed will contain between 25 and 40 percent protein. agrino.org/fishing/htmldocs/ frswtrfish.html

Sources of protein –Fish meal High protein feed derived from fish. –Animal waste products Blood meal –High protein feed derived from blood collected during the slaughter process. Meat scraps –Soybean meal High protein feed produced from soybeans.

Protein requirements Carnivore fish –Animals that eat meat. –Require 50% of its protein from animal sources. Herbivore fish –Animals that eat plants. –Need only about 30% of the protein in their feed from animal sources. Omnivores –Animals that eat both plants and animals. –Need only about 30% of the protein in their feed from animal sources.

What is the role of fats in fish nutrition? Fats –A required component of fish feeds. –Composed of fatty acids. –Used for proper health and growth. –Amount of fat in a feed usually between 4 and 15 percent.

Fat requirements Type of fat needed in fish feed depends on temperature of water. To be digested, fat must be able to melt. To melt, must have melting point below water temperature. Cold water fish (trout) –Unsaturated fat derived from plants (vegetable oil). Warm water fish (tilapia) –Saturated fat derived from animal products.

What is the role of carbohydrates in fish nutrition? Carbohydrates –A required component of fish feed. –Source of energy for fish. –Organic compounds composed of carbon, hydrogen, & oxygen. –Plants including sugars, starches, and cellulose are sources.

Carbohydrate requirements Fish herbivores (carp) –Better capable of digesting carbohydrates. –An enzyme (amylase) in their digestive system. Fish carnivores (catfish) –Can’t digest carbohydrates as well. –Only need 10% carbohydrates in ration.

What is the role of minerals in fish feed? Minerals –Inorganic materials needed for health and growth. –Most only needed in small amounts. –Large amounts of minerals may be fatal to fish. –Often called trace elements Needed in very small quantities.

Required Minerals Calcium Iron Silicon Manganese Magnesium Boron Cobalt Copper Iodine Molybdenum Selenium Sodium catfish-2795/index.shtml

Minerals Testing the water can show mineral deficiencies. Can give fish two ways –Add directly to the water. If water is flowing or moving may be a waste –Added to a commercially prepared feed.

What is the role of vitamins in fish nutrition? Vitamins –Organic compounds needed in small amounts for proper growth and maintenance of body functions. –Specific vitamins are needed for different body functions. –Deficiencies can cause poor growth, anemia, skin lesions, clubbed gills and other problems.

Types of Vitamins Water-soluble –Taken in, used, and then excreted. –Include Thiamin, Riboflavin, and Folic Acid. Fat-soluble –Taken in to the body and stored. –If excess amounts consumed can be unhealthy. –Include vitamin E, A, and D.

Review / Summary What is the role of protein in fish nutrition? What is the role of fats in fish nutrition? What is the role of carbohydrates in fish nutrition? What is the role of minerals in fish nutrition? What is the role of vitamins in fish nutrition?