nutrition and feeding 257 



Table 32. suggested feeding frequencies for salmonids. (source; washing- 

 ton DEPARTMENT OF FISHERIES, UNPUBLISHED.) 



FiSH SIZE (NUMBER/POUND) 



SPECIES 1,500 1,000 750 500 250 125 75 30 10-LARGER 



TIMES PER DAY 



body weight, they would receive 10 feedings per day; if they receive T'o of 

 body weight in feed per day it would be fed in one feeding. 



Channel catfish reared in raceways produce more gain when fed twice 

 daily than when they are fed only once daily. In some situations, more 

 than two feedings per day will not improve the feed consumption or 

 growth rate in pond fed catfish. 



The following statements relate to feeding frequency: 



The feeding frequency does not significantly influence the mortality of 

 fry once they pass the initial feeding stage. 



Frequently fed fingerlings utilize their feed more efficiently than those 

 fed less frequently, resulting in better feed conversion. 

 Frequent feeding of fingerlings reduces starvation and stunting of the 

 small fish in a group. Generally, more frequent feeding results in greater 

 uniformity in fish size. 



The accumulation of waste feed on the bottom of a rearing unit due to 

 the infrequent feeding of large amounts of feed is a principal factor caus- 

 ing inefficient utilization of feed. 



When uneaten feed lies on the bottom of the tank, water-soluble nu- 

 trients are leached out, resulting in poor utilization of the feed. 

 In general, the number of feedings per day should be greater for dry 

 feed than for soft moist feeds. 



A rule of thumb is that 90% of the feed should be eaten in 15 minutes or 

 less. 



Feed Sizes 



The size of feed particles is critical in the feeding of fish. If particles are 

 too large, the fish will not be able to ingest them until the water disin- 

 tegrates the feed to an acceptable size. When this occurs, nutrients leach 

 out of the pellet, wasting feed and possibly polluting the water. When the 



