NUTRIENTS AND FEEDING [objectives] Explain how animals and plants vary in the acquisition of nutrients Discuss the nutrient requirements of aquaculture species Explain how nutrient requirements are met during culture Describe kinds and sources of feed Identify and evaluate approaches in feeding Discuss buying and storing feed
NUTRIENTS & FEEDING Chapter 5 Nutrient – a substance used by organisms to live and grow. Food – any material ingested that contains needed nutrients. Ingest – consume or eat food.
TROPHIC LEVELS Producer (Autotroph)– plants, algae, and cyanobacteria make their food by photosynthesis. Consumer (Heterotroph) – must consume other organisms. *herbivore – eats plants only *carnivore – eats meat only *omnivore – eats both plants and meat *detritivore – eats decaying plant/animal matter. Decomposer – (bacteria/fungi) have external digestion.
PRODUCERS cyanobacteria
PRODUCERS algae
PRODUCERS plants
CONSUMERS herbivores
CONSUMERS carnivores
CONSUMERS omnivores
CONSUMERS detritivore
DECOMPOSERS
MAJOR NUTRIENTS Proteins – made from amino acids; necessary for tissue growth and repair. Fats – made from fatty acids; necessary for cell membranes and energy. Carbohydrates – made from saccharides; necessary for energy. Vitamins – water soluable and fat soluable; necessary for enzymes. Minerals – inorganic earth materials; necessary for coenzymes.
MEETING NUTRIENT NEEDS Promote natural food growth – fertilizer Culture food materials – brine shrimp and aquaponic lettuce Capture food materials – copepods for snapper and cobia Provide manufactured feed – floating or sinking fish feed
FERTILIZER
CULTURE FOOD MATERIALS
CAPTURE FOOD MATERIALS
PROVIDE MANUFACTURED FEED
MANUFACTURE OF FEED Ingredients – corn, soybean meal, meat/bone meal, blood meal, fish meal. Life-stage feeds – larval, starter, grower, broodstock. Bouyancy – floating feed contains more air; can observe animals. Particle preparation – meals and pellets.
FEEDING APPROACHES Scheduled feeding – provided at specific time (ex. Redclaw crawfish before dark) Juveniles need to feed more frequently than older animals. Free-access feeding – making food available all the time by using automatic feeders.
BUYING AND STORING FEED Small producers usually buy feed in 50-pound bags. Large producers usually buy feed in bulk. When storing feed avoid the following: *insect infestation *rodent damage and contamination *spoilage or rancidity *contact with water *chemical contamination