Aquaponics FISH HEALTH REF: Fish Health

Fish health Keeping fish healthy Proper temperature Proper water quality Quality feed All aspects dependent on species Understanding anatomy and physiology of fish species helps in the detection of abnormalities caused by disease

Basic anatomy of fish Fins Stiff rays covered by skin Some jointed Some bony, stiff and unjointed Spines Almost ½ fin rays in the Dorsal fin of tilapia are bony spines Each fin performs a specific function FIN FUNCTION DORSAL Protects fish against rolling and assists in sudden turns and stops CAUDAL Gives fish momentum during movement ANAL Stabilizes the fish while swimming PELVIC Assists the fish in going up or down through the water column, turning sharply, and stopping quickly PECTORAL Used by the fish for maneuvering

Basic anatomy of fish

Basic Anatomy of fish Skin Epidermis (outer) layer Epithelial cells arranged one above the other Constantly shed and replaced Slime cells Production of mucoid secretions Protective covering Dermis (inner) layer Under epidermis

1 Epidermis 2 Scales 3 Dermis 4 Flesh

Basic anatomy of fish Scales Overlap creating flexible protective armor Lie in pockets in the dermis and come out of the connective tissue Covered by epithelial layer Deeper dermis Fibroblasts Collagen Blood vessels

Basic anatomy of fish Pigment (color) cells Cells are named for the pigment they contain Quickly change color Movement of melanin grains within each cell Dispersion causes absorption of more light creating a darkened area Constriction less light absorption area goes pale Mating Survival Feeding

Basic anatomy of fish Gills – Respiration Delicate system of blood vessels covered by very thin epithelium Gaseous exchange Located under gill covers (operculum) Walls of pharynx perforated by five slit-like openings Tissue between slits is gill arch (four gill arches) Gills are located on gill arches

Basic physiology of fish Physiology – function of the body systems Aquatic animals – systems adapted to water environment 9 body systems Circulatory Digestive Excretory Muscular Nervous Reproductive Respiratory Sensory Skeletal Each system is part of the process of fish: Consuming food Consuming oxygen Excreting ammonia rich waste Excreting carbon dioxide

Basic physiology of fish Circulatory System – heart, veins, arteries Distributes blood throughout body Transports oxygen and carbon dioxide

Basic physiology of fish Digestive system – converts food into a form that can be used by the body for maintenance, growth, and reproduction carnivore, omnivore, herbivore All parts of body that take in and assimilate food Mouth Esophagus Stomach Intestines Liver Anus Etc.

Basic fish physiology Excretory system – eliminates waste from the body Kidneys Filters waste from the blood Urinary ducts Urinary bladder Holds waste until excretion Urinary opening Excretion of waste

Basic fish physiology Muscular system – provides movement internally and externally Vary in strength and function Contract and relax to cause movement Obtaining food and oxygen Eliminating waste

Basic physiology of fish Nervous system – complex, supplies the body with information about internal and external environment Conveys sensation impulses (electrical-chemical changes) Brain Spinal cord Nerve fibers Sensory receptors Stimuli received by sense organs and receptors Stimuli conveyed through nerve fibers Stimuli interpreted by spinal cord/brain Brain/spinal cord send response through nerve fibers

Basic physiology of fish Reproductive system – creation of new organisms of the same species via union sperm and egg Males – testes – sperm Female – ovaries – eggs (ova) Sperm and egg unite and zygote forms Incubation of zygote leads to development of new organism Understanding reproduction based on species is important to the success of culturing a species

Basic physiology of fish Respiratory system – takes in oxygen from environment, delivers the oxygen to cells and tissues of the body; collects carbon dioxide for the cells and tissues of the body and delivers the carbon dioxide to the environment Water is taken in the mouth forced over gills where oxygen is removed by diffusion into the blood

Basic physiology of fish Sensory System – sight, touch, taste, smell, hearing – relays information through the nervous system Lateral line – electrical currents

Basic physiology of fish Skeletal system – framework that gives the body shape and protects the organs Bone – hard material Cartilage – soft material Tissue and organs attach to the skeleton