Table 2. — Mortality in kilograms for individual samples. 



curves showing weight loss for Tests "A" and 

 "B" continued at a much reduced level for the 

 last 96 hr. The Test "C" curves started a sim- 

 ilar trend, but during the final days of the 

 test period these curves started downward, in- 

 dicating the fish were possibly regaining some 

 weight. 



Daily mortality was tabulated in kilograms 

 (Table 2) . The greatest mortality, 34.0%, oc- 

 curred to Test "C" fish held in the vats aerated 

 by agitators. Test "C" catfish held in the vats 

 supplied with compressed air suffered 15.0% 

 mortality. Mortality for the 320.3 and 640.6 kg 

 (20.0 and 40.0 lb.) loadings of fish in Tests "A" 

 and "B" averaged 4.5% and 8.0%, respectively. 

 Almost no mortality occurred to fish held in the 

 two control pots in Test "B" and none occurred 

 to the Test "C" fish held in the cool pond 

 water. 



The effect of the daily handling on weight 

 loss and mortality was checked with two control 

 groups in Test "B". These two containers, one 

 with a fish density of 320.3 kg per cubic meter 

 (20.0 lb. per cu ft) of water and the other 

 with a fish density of 640 kg (40.0 lb.), were 

 weighed every 24 hr. The weight loss for the 

 controls averaged 9.3%; for the pots weighed 

 every 24 hr, the loss was 8.4% . It appears that 

 daily weighing did not contribute to weight loss. 

 The daily handling during weighing did cause 

 mortality. In the containers handled every 

 24 hr, 8.0% of the fish held at the higher den- 

 sity died and 4.5% of the fish held at the lower 

 density succumbed. None of the 320.3 kg 

 (20.0 lb.) control group died and only 0.9% 

 of the fish expired at the heavier loading of 

 640.6 kg (40.0 1b.). 



The test results comparing weight losses of 

 fish held at concentrations of 320.3 kg and 640.6 

 kg per cubic meter (20.0 and 40.0 lb. per cu ft) 

 of water indicated that at these loadings density 

 had little effect. At the end of 168 hr, con- 

 tainers with 320.3 kg (20.0 lb.) of fish incurred 

 an average weight loss of 8.4% and those with 

 640.6 kg (40.0 lb.) of fish lost 8.1%. Even 

 though density did not appear to affect weight 

 loss, it did contribute to higher mortality. At 

 the end of the test period, containers with the 

 heavier loadings sustained twice the mortality 

 of those with 320.3 kg (20.0 lb.) of fish: 8.0% 

 compared to 4.5%. 



The results of the tests comparing weight 

 losses in vats aerated by compressed air and 

 by agitators indicated the peak weight loss was 

 slightly greater in the compressed air situation 

 than with agitators (6.9% compared to 4.2%). 

 However, a substantially greater mortality oc- 

 curred in the vat with agitators (34.0% com- 

 pared to 15.0%). 



The two containers of fish held in the cool 

 pond water fared the best of any of the test 

 groups. The peak weight loss for those fish 

 averaged 2.0%. No mortality was recorded. 



The test results for all groups of fish held 

 in the plant vats indicated weight losses were 

 fairly similar at the end of 48 hr (Fig. 3) . The 

 average loss during this period of 45 kg per 

 metric ton (4.5 lb. per cwt) constitutes 82.0% 

 of the peak weight loss of 55 kg per metric ton 

 (5.5 lb. per cwt) for these groups. The max- 

 imum weight losses for each test situation show 

 the containers with 329.3 and 640.6 kg (20 and 

 40 lb.) of fish lost 84.0 and 81.0 kg per metric 

 ton (8.4 and 8.1 lb. per cwt). Fish held in 



