47r) FISH HATCHERY MANAGF.MF.NT 



Ciliate Protozoan One-celled animal bearing motile cilia. 



Circuli The more or less concentric growth marks in a fish scale. 



Clinical Infection An infection or disease generating obvious symptoms 

 and signs of pathology. 



Cloaca The common cavity into which rectal, urinary, and genital ducts 

 open. Common opening of intestine and reproductive system of male 

 nematodes. 



Closed-Formula Feed (Proprietary Feed) A diet for which the formula 

 is known only to the manufacturer. 



Coelomic Cavity The body cavity containing the internal organs. 



Coelomic Fluid Fluid inside the body cavity. 



Coelozoic Living in a cavity, usually of the urinary tract or gall bladder. 



Cold Water Disease See Peduncle Disease; Fin Rot Disease. 



Coldwater Species Generally, fish that spawn in water temperatures 

 below 55°F. The main cultured species are trout and salmon. See Cool- 

 water Species; Warmwater Species. 



Colloid A substance so finely divided that it stays in suspension in 

 water, but does not pass through animal membranes. 



Columnaris Disease An infection, usually of the skin and gills, by Flex- 

 ibacter columnaris, a myxobacterium. 



Communicable Disease A disease that naturally is transmitted directly 

 or indirectly from one individual to another. 



Compensation Point That depth at which incident light penetration is 

 just sufficient for plankton to photosynthetically produce enough oxy- 

 gen to balance their respiration requirements. 



Complete Diet (Complete Feed) See Balanced Diet. 



Complicating Disease A disease supervening during the course of an 

 already existing ailment. 



Compressed Applied to fish, flattened from side to side, as in the case 

 of a sunfish. See Depressed. 



Conditioned Response Behavior that is the result of experience or 

 training. 



Congenital Disease A disease that is present at birth; may be infec- 

 tious, nutritional, genetic, or developmental. 



Congestion Unusual accumulation of blood in tissue; may be active 

 (often called hyperemia) or passive. Passive congestion is the result of 

 abnormal venus return and is characterized by dark cyanotic blood. 



Constant-Flow Treatment Continuous automatic metering of a chemi- 

 cal to flowing water. 



Contamination The presence of material or microorganisms making 

 something impure or unclean. 



Control (Disease) Reduction of mortality or morbidity in a population, 

 usually by use of drugs. 



