Aquaculture Feed and Fertilizer Resources Information System
 

Channel catfish - Feeding

Feeding rates and frequencies

Because feed represents more than 50 percent of aquaculture inputs, particularly in intensive farming systems, many studies have recently been carried out to determine the best feeding regime for cultured channel catfish, with varying, and sometimes contradictory, results. The daily feed ration for channel catfish is affected by many factors, including water temperature, fish size and water quality. Therefore, no single feed or feeding method can be applied under all circumstances.

Generally speaking, newly hatched fry are fed several times daily at 6–10 percent of fish weight. Fingerlings are fed between 2 and 5 percent of their body weight per day, divided into two or more feedings, while broodfish are fed 1 to 2 percent of their weight per day. However, most catfish farmers feed their fish once daily to satiation, 7 days a week, during the warmer months.

Wu et al. (2004) evaluated the effect of feeding time (morning vs evening), feeding frequency (one vs two times a day) and intermittent fasting (6 days of feeding, 1 day of fasting) on production, feed conversion ratio (FCR), survival, weight-length relationship, percent dressout and body composition of channel catfish reared in earthen ponds. These growth parameters were not affected by any of the four dietary treatments. These results suggest that when catfish are fed to apparent satiation there is no advantage to multiple feedings, to feeding at a specific time of day or to intermittent fasting in earthen ponds. Similar results were reported on catfish reared in a closed recirculating raceway system (Jarboe and Grant, 1996).

In another study, Robinson and Li (2007b) studied the effects of fish size (small, medium and large) and feeding frequency (feeding daily or every other day (EOD) to satiation) on feed consumption, growth, production and FCR of pond-raised channel catfish. The authors found that channel catfish consumed more feed (46–68 percent) and converted the feed more efficiently (11 percent) when fed EOD to satiety compared with fish fed daily, regardless of fish size. However, net production was reduced by 16 percent when the fish were fed EOD. The authors concluded that feeding catfish less than daily may be acceptable as a short-term strategy when economic conditions justify it, but it does not appear to be a sound practice in the long term.

In contrast, other studies revealed that more frequent feeding is more profitable for catfish culture. Nanninga and Engle (2010) found that growth rates, gross and net yield of pond- raised catfish fed every day, every other day or every third day increased significantly with increased feeding frequency (i.e. feeding every day was  preferable to every other day or every third day).

It is suggested that channel catfish are fed in the morning, as the dissolved oxygen begins to increase during warm weather. When minimum (morning) water temperature was above 26 °C, feeding two times daily resulted in maximum food consumption and growth; when morning temperature was 22–26 °C, feeding once per day was optimal; and when morning water temperature was below 20 °C, alternate-day feeding resulted in the highest food consumption. These data indicate that catfish should be fed twice daily as soon as water temperature warms up in the early summer and fed on this schedule until the water temperature begins to decrease in the fall. In cool weather, it is better to feed the fish in the afternoon, because water temperature is usually higher than in the morning. Winter feeding can lead to a small weight gain and will increase disease resistance of catfish during overwintering. It has been suggested that feeding overwintered adult fish 1 percent of their body weight on days that water temperature is above 12 °C is appropriate. Fingerlings may be fed at a rate of 1 percent of body weight, three times weekly throughout the winter.

Feeding methods

In hatchery, channel catfish fry are fed either by hand or using an automatic feeder. For fingerlings and fattening stages, feed is typically blown onto the surface of the water using mechanical feeders. Feeds should be scattered over a wide area to provide all the fish with an equal chance to feed. This helps minimize feed loss and reduces fish stress, which in turn leads to better performance. It is desirable to feed on the pond sides; however, feed must be distributed along the upwind side to minimize the amount of feed washed ashore. Demand feeders have been successfully used in cage culture of channel catfish; however, their use should be accompanied by aeration. Floating feed rings can also be used in catfish feeding. However, in a preliminary study, Lyon et al. (2008) studied the effect of a floating feed ring on advanced channel catfish fingerling production in ponds. They found that the use of feed rings did not enhance growth or FCR.