CONCLUSIONS 



Based on the test results, the following con- 

 clusions were made concernino: catfish weight 

 loss and mortality during holding: 



1. Channel catfish lose weight during hold- 

 ing. Most of the loss occurs during the first 

 48 hr and the test results showed 82.0% of the 

 maximum average weight loss of 55 kg per 

 metric ton (5.5 lb. per cwt) occurred during 

 this period. 



2. Weight loss was similar for fish held at 

 densities of 320.3 and 640.6 kg per cubic meter 

 (20.0 and 40.0 lb. per cu ft) of water but mor- 

 tality was twice as much, 8.0''^ , for the higher 

 concentrations of fish. 



3. Handling the fish every 24 hr to weigh 

 them did not contribute to weight loss but did 

 cause mortalities of 4.5 '^r and 8.0% to occur 

 in containers with loadings of 320.3 and 640.6 



kg of fish per cubic meter (20 and 40 lb. per 

 cu ft) of water. 



4. Our data showed fish held in vats with 

 agitators suffered slightly less weight loss than 

 those held in vats supplied with compressed air. 

 Mortalities, however, were 34.0% with agi- 

 tators and 15.0% with compressed air. Be- 

 cause of this large mortality, and a number of 

 positive weight readings during the final days 

 of this test, we are hesitant of accepting these 

 results. Additional studies should be conducted 

 before judging the merits of aerating vats with 

 agitators or compressed air. 



5. Fish held best in cool pond water of 8.9° 

 to 15.0° C (48.0° to 59.0° F) : they suffered 

 no mortality and had a maximum weight loss 



of 2.0' 



Similar fish held in vats with 21.7° C 



(71° F) water incurred twice the weight loss 

 and had mortalities averaging 15.0% and 

 34.0%. 



GPO 999-665 



