486 FISH HATCHERY MANAGEMENT 



Inoculation The introduction of an organism into the tissues of a living 

 organism or into a culture medium. 



Instinct Inherited behavioral response. 



Intensive Culture Rearing of fish at densities greater than can be sup- 

 ported in the natural environment; utilizes high water flow or 

 exchange rates and requires the feeding of formulated feeds. 



Interspinals Bones to which the rays of the fins are attached. 



Intestine The lower part of the alimentary tract from the pyloric end of 

 the stomach to the anus. 



Intragravel Water Water occupying interstitial spaces within gravel. 



Intramuscular Injection Administration of a substance into the mus- 

 cles of an animal. 



Intraperitoneal Injection Administration of a substance into the peri- 

 toneal cavity (body cavity). 



In Vitro Used in reference to tests or experiments conducted in an artifi- 

 cial environment, including cell or tissue culture. 



In Vivo Used in reference to tests or experiments conducted in or on 

 intact, living organisms. 



Ion Exchange A process of exchanging certain cations or anions in 

 water for sodium, hydrogen, or hydroxyl (OH ) ions in a resinous 

 material. 



IPN See Infectious Pancreatic Necrosis. 



Isotonic No osmotic difference; one solution having the same osmotic 

 pressure as another. 



Isthmus The region just anterior to the breast of a fish where the gill 

 membranes converge; the fleshy interspace between gill openings. 



Kidney One of the pair of glandular organs in the abdominal cavity that 

 produces urine. 



Kidney Disease See Bacterial Kidney Disease. 



Kilogram Calorie The amount of heat required to raise the tempera- 

 ture of one kilogram of water one degree centigrade, also called kilo- 

 calorie (kcal), or large calorie. 



Larva (plural: Larvae) An immature form, which must undergo change 

 of appearance or pass through a metamorphic stage to reach the adult 

 state. 



Lateral Band A horizontal pigmented band along the sides of a fish. 



Lateral Line A series of sensory pores, sensitive to low- frequency vibra- 

 tions, located laterally along both sides of the body. 



LDV See Lymphocystis Disease. 



