498 FISH HATCHERY MANAGEMENT 



Sulfomerthiolate (Thimerfonate Sodium) Used as an external disinfec- 

 tant of living fish eggs. 



Sulfonamides Antimicrobial compounds having the general formula 

 H^NSO^ and acting via competition with /)-aminobenzoic acid in folic 

 acid metabolism (for example, sulfamerazine, sulfamethazine). 



Superior As applied to the mouth, opening in an upward direction. 



Supersaturation Greater- than- normal solubility of a chemical as a 

 result of unusual temperatures or pressures. 



Supplemental Diet A diet used to augment available natural foods. 

 Generally used in extensive fish culture. 



Susceptible Having little resistance to disease or to injurious agents. 



Suspended Solids Particles retained in suspension in the water column. 



Swim Bladder See Air Bladder. 



Swim-up Term used to describe fry when they begin active swimming 

 in search of food. 



Syndrome A group of signs that together characterize a disease. 



Temperature Shock Physiological stress induced by sudden or rapid 

 changes in temperature, defined by some as any change greater than 3 

 degrees per hour. 



Tender Stage Period of early development, from a few hours after fertil- 

 ization to the time pigmentation of the eyes becomes evident, during 

 which the embryo is highly sensitive to shock. Also called green-egg 

 stage, sensitive stage. 



Terramycin See Oxytetracycline. 



Testes The male reproductive organs. 



Therapeutic Serving to heal or cure. 



Thiamine An essential B-complex vitamin that maintains normal car- 

 bohydrate metabolism and is essential for certain other metabolic 

 processes. 



Thiosulfate, Sodium (Sodium Hyposulfite, Hypo, Antichlor) Na2S203; 

 used to remove chlorine from solution or as a titrant for determination 

 of dissolved oxygen by the Winkler method. 



Titration A method of determining the strength (concentration) of a 

 solution by adding known amounts of a reacting chemical until a color 

 change is detected. 



Tocopherol Vitamin E; an essential vitamin that acts as a biological 

 antioxidant. 



Topical Local application of concentrated treatment directly onto a 

 lesion. 



Total Dissolved Solids (TDS) See Dissolved Solids. 



Total Length The distance from the most anterior point to the most 

 posterior tip of the fish tail. 



