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Water quality in impoundments and modifications from destratification
Irwin, W.H.; Symons, J.M.; Robeck, G.G. (1967). Water quality in impoundments and modifications from destratification. US Deptartment of the Interior: Cincinnati. 45 pp.
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| Auteurs | | Top |
- Irwin, W.H.
- Symons, J.M.
- Robeck, G.G.
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| Abstract |
A study was conducted with channel catfish to compare raw and pelleted crawfish processing waste with a commercial feed in ponds. The feasibility of feeding such foods in shallow ponds was explored at Ben Hur Farm, East Baton Rouge Parish, Louisiana. Raw crawfish processing waste was passed through a meat grinder, weighed and fed. Dried crawfish waste was ground into a meal and compressed into 1/8- x 1/4- inch pelleted form. The control was a complex, commercial fish ration containing a number of ingredients with vitamin and mineral fortification. Nine experimental ponds of approximately 0.1 to .25 acres each were stocked with channel catfish at a rate of 1,455 per acre. The ponds were blocked into three groups according to size and the three rations were randomly assigned to the ponds in each block. The fish were fed their respective rations daily at a rate of 3 per cent of their body weight for 105 days. The commercial ration and the pelleted crawfish waste were fed on a dry weight basis while the raw waste was fed on the basis of its wet weight. A sample of fish was seined every two weeks to adjust feeding rates. Experimental ponds had mean depths of approximately 2 feet. Surface temperatures reached 103°F and maximum bottom temperatures were 88°F. Channel catfish cleaned up all of each of the rations at even the highest temperature during the experimental period. Crawfish waste, which is about 35 per cent crude protein on a dry matter basis, appeared to be a potential feed for catfish when fed in pelleted form but not when fed raw. The raw waste rapidly dispersed in water and most was available for feed. Mean weight gains were .232, .345, 447 pounds for raw crawfish waste, pelleted crawfish waste and the pelleted commercial ration, respectively. Crawfish waste, when fed to channel catfish in pelleted form, produced reasonably good growth, however, the commercial ration gave the best growth. |
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