Catfish grown at high densities require a nutritionally complete feed for good growth and health. Commercially prepared catfish feeds, available in bulk or in bags, should contain from 26- to 36-percent crude protein plus all essential vitamins and minerals to be called "complete." Feeds containing 32-percent crude protein are adequate and the most economical for food fish production. Feeds of 26-percent crude protein can be used for winter feeding and by people who produce small quantities of catfish for home use.
Both sinking (pelleted) or floating (extruded) feed can be fed to catfish. Both types, if complete, give adequate growth under normal conditions. Floating feeds are more expensive, but they allow the producer to observe feeding activity. Feeding activity is extremely important in determining how much to feed, and it is usually the best opportunity the producer has to judge the health and vigor of the fish. A mixture of 15-percent floating and 85-percent sinking feed can be used to cut costs and still allow observation of feeding activity.
Fish feeds come in various sizes. Crumbles (crushed pellets) can be fed when fingerlings are less than 3 inches long. Fish larger than 3 inches can be fed a 3/16-inch pellet until they reach market size. Fish are usually fed out on 1/4-, 5/16-, or 3/8-inch pellets once they reach 1/2 pound in weight.
One of the biggest problems producers encounter is knowing how much to feed each day. Overfeeding wastes feed and money, and it can cause water-quality problems. Catfish will grow at their maximum rate when fed all they will voluntarily eat (called "satiation"). However, trying to satiate the fish usually results in overfeeding.
Timed Feeding. Research has shown that catfish grow most efficiently when fed about 90 percent of all they will voluntarily eat. This optimum feeding rate is generally reached when catfish are fed only the amount they will eat in 5 to 10 minutes. It is important that the fish eat as much as they want, without leaving any excess.
Feed Conversion Method. Another way to estimate the amount to feed during summer months is to calculate the total initial weight of the fish in the pond and feed the percentage of body weight recommended in Table 2 (below) each day for a 2-week period. Every 2 weeks, the weight gain can be estimated based on the feed conversion ratio (FCR) and the ration adjusted. The formulas for this procedure and an example computation are shown in Table 3 (below).
|
Water temperature |
Fish size |
Feed allowace per day-percent of fish weight |
Weight of feed per acre per day per 1,000 fish |
Date |
degree F |
lb. |
percent |
lb. |
4-15 |
68 |
0.04 |
2.2 |
0.9 |
4-30 |
72 |
0.06 |
2.8 |
1.7 |
5-15 |
78 |
0.11 |
3.0 |
3.3 |
5-30 |
80 |
0.16 |
3.0 |
4.8 |
6-15 |
83 |
0.21 |
3.0 |
6.3 |
6-30 |
84 |
0.28 |
3.0 |
8.4 |
7-15 |
85 |
0.35 |
3.0 |
10.5 |
7-30 |
85 |
0.42 |
2.8 |
11.8 |
8-15 |
86 |
0.60 |
2.4 |
14.4 |
8-30 |
86 |
0.75 |
2.0 |
15.0 |
9-15 |
83 |
0.89 |
1.8 |
16.0 |
9-30 |
79 |
1.01 |
1.6 |
16.0 |
10-15 |
73 |
1.10 |
1.2 |
13.2 |
| * For channel carfish in ponds, stocked with 5-inch fingerlings and harvested at 1.1 pounds. | ||||
Estimated weight gain = |
total pounds of feed fed x 0.556 (FCR = 1:1.8) |
New total fish weight in pond = |
estimated weight gain + last total fish weight |
New daily feeding rate = |
new total weight of fish X (percentage of body weight from Table 2) |
Example:
| |
Est. wt. gain = |
2,100 x 0.556 = 1,167.6 or 1,168 (lb. gain) |
New total fish wt. = |
5,000 + 1,168 = 6,1 68 |
New daily feeding rate = |
6,168 x 0.03 (from Table 2) = 185.04 or 185 lb./day |
In the example in Table 3, 185 pounds of feed would be fed each day for the next 2 weeks. Then a new feeding rate would be calculated using this method. It should be pointed out that this method is only as good as the ability to estimate the FCR.
Fish Sampling Method. A third method to calculate feeding rates is to estimate the total weight of the fish based on the weight of a sample. Although research has shown that average sample weights can vary from 8 to 19 percent from true average weights, this method is still effective.
At 2-week intervals, the producer captures a sample of 100 fish at random with a net (not hook and line) and weighs them. The producer can then calculate the next feeding rate by estimating the total fish weight in the pond from this sample. The formulas for these calculations and a sample estimate are shown in Table 4.
Average weight of individual fish = |
weight of 100 fish /100 |
New total fish weight = |
average weight X number of fish in the pond |
New daily feeding rate = |
new total weight of fish X (percentage of body weight from Table 2) |
Example:
| |
Ave. wt. of fish = |
25 /100 = 0.25 lb. per fish |
New total fish wt. = |
0.25 X 20,000 = 5,000 lb. |
New daily feeding rate = |
5,000 X 0.03 (from Table 2) = 150 lb./day |
In the example in Table 4, 150 pounds of feed would be fed each day for the next two weeks. Then a new feeding rate would be recalculated based on another sample.
Using Table 2, the daily feed allowance, as a percentage of body weight, can be estimated as fish grow. Table 2 is a guide for feeding catfish during the spring, summer, and early fall growing seasons, beginning with fish newly stocked in April. Remember, this table is only a guide and fish may respond differently from day to day and from pond to pond.
Feeding less than 35 pounds of feed per acre of pond per day will minimize low-oxygen problems caused by high stocking densities and feeding rates. However, emergency aeration may be needed at times during the summer, even at this feeding rate. If effective aeration equipment is available, feeding rates of up to 100 pounds of feed per acre per day can be used. The majority of producers should by to maintain feeding rates below 70 pounds of feed per acre per day to grow out large numbers of fish but minimize risk.
Feeding fish twice each day can be advantageous when fish are less than 1/2 pound (usually April though July). Twice-daily feedings should be at least 6 hours apart to allow for digestion. When fed twice a day, catfish will eat and gain more than when they are fed once a day.
Catfish can be trained to eat at nearly any time of day. During the summer, it is not advisable to feed too early in the morning or after sundown, because of potential low-oxygen problems. Fish do not consume as much feed if o xygen is low, and the process of digestion increases oxygen uptake. Feeding around 9:00 a.m. in the summer is a good practice if oxygen levels are good. Once a feeding time is established, maintain it. Catfish will feed better if a daily routine is followed. For the same reason, try to feed in the same location each day. However, you may have to change the feeding location to account for wind direction and velocity when you are using floating feed.
Feed catfish 7 days a week. They will grow less quickly and efficiently if they are fed less often. Remember: no feed, no gain; no gain, no profit.
Catfish are naturally aggressive and attempt to dominate each other over food. So, spread the feed out over a large area in the pond to allow smaller fish a better chance to feed. This practice will result in a more uniform size at harvest. It is very important to widely distribute feed across the surface of large ponds because of the large number of fish to be fed.
The growth of channel catfish slows during the winter, but feeding at a lower rate is important. Without feed during the winter, catfish will lose weight and be less resistant to disease when the water begins to warm in the spring. Catfish do feed at low temperatures, just not as often.
A satisfactory winter feeding schedule for catfish in ponds is to feed about 1 percent of their body weight every other day when the water temperature is between 55 and 65 degrees F. Feed 1 percent of their body weight twice a week when the water temperature is between 45 and 54 degrees F. Feed in the afternoon when the temperature is highest, and on sunny days. Many producers feed sinking pellets in winter, if the fish will not come to floating feed. More information on winter feeding of catfish can be found in Extension circular ANR-457, "Feeding Catfish During Winter''
Good feed conversion depends on good management. A producer who manages the catfish well can achieve feed conversions between 1.5 and 2 pounds of feed to 1 pound of fish gain. A producer can increase profits by about 1 to 2 cents per pound of fish for each tenth of a pound of improved feed conversion, depending on the price of feed (Table 5). The opposite is true when management is poor.
Feed Price/ton | |||||||
FCR |
$230 |
$250 |
$270 |
$290 |
$310 |
$330 |
$350 |
1.3 |
15.0 |
16.3 |
17.6 |
18.9 |
20.0 |
21.5 |
22.8 |
1.4 |
16.1 |
17.5 |
18.9 |
20.3 |
21.7 |
23.1 |
24.5 |
1.5 |
17.3 |
18.8 |
20.3 |
21.8 |
23.3 |
24.8 |
26.3 |
1.6 |
18.4 |
20.0 |
21.6 |
23.2 |
24.8 |
26.4 |
28.0 |
1.7 |
19.6 |
21.3 |
23.0 |
24.7 |
26.4 |
28.1 |
29.8 |
1.8 |
20.7 |
22.5 |
24.3 |
26.1 |
27.9 |
29.7 |
31.5 |
1.9 |
21.9 |
23.8 |
25.7 |
27.6 |
29.5 |
31.4 |
33.3 |
2.0 |
23.0 |
25.0 |
27.0 |
29.0 |
31.0 |
33.0 |
35.0 |
2.1 |
24.2 |
26.3 |
28.4 |
30.5 |
32.6 |
34.7 |
36.8 |
2.2 |
25.3 |
27.5 |
29.7 |
31.9 |
34.1 |
36.3 |
38.5 |
2.3 |
26.5 |
28.8 |
31.1 |
33.4 |
35.7 |
38.0 |
40.3 |
2.4 |
27.6 |
30.0 |
32.4 |
34.8 |
37.2 |
39.6 |
42.0 |
2.5 |
28.8 |
31.3 |
33.8 |
36.3 |
38.8 |
41.3 |
43.8 |
| * rounded to the nearest tenth of a cent | |||||||
Store feeds in a cool, dry place. Damp storage areas (bins or rooms)
can cause mold to grow on feeds. Heat causes loss of vitamins. Do not use
feeds that have been stored for more than 8 weeks during warm weather. Never
use feeds that are moldy or clumped together. Eating contaminated or vitamin-deficient
feed can slow growth, lower resistance to disease, and cause deformities
or death.