III/E-6
EXPERIMENTS WITH SUPPLEMENTAL FEEDS FOR CHANNEL CATFISH

by

O. W. TIEMEIER, C. W. DEYOE and S. WEARDEN
Tuttle Creek Fisheries Research Laboratory
Manhattan, Kansas, U.S.A.

Abstract

Fingerling channel catfish were fed with diets of dry feed in 12 polyethylene-lined earthen ponds where water level was maintained at 0.0582 surface hectare.

Diets contained: 25 percent protein and 1,874 calories per kg (metabolizable energy); 25 percent protein and 2,168 calories; 25 percent protein and 1,874 calories but low in animal protein; and 30 percent protein and 2,316 calories.

Conversions near one kg of feed per kg of fingerling fish were obtained with all four diets. Survival of 11,450 fish stocked was 95.17 percent.

Large and small age class II fish stocked in combination or separately required slightly over two kg of feed to produce one kg of fish. A difference in initial average weight of one g between large and small fish resulted in a difference of 3.97 g in final weight.

In progeny tests, 170 g of fry stocked in each of 6 kg during June produced fingerlings 10.6 to 19.5 g in average weight.

ESSAIS DE DIVERSES FORMULES ALIMENTAIRES POUR L'ELEVAGE DU CHANNEL CATFISH (ICTALURUS PUNCTATUS)

Résumé

Quatre formules d'aliments secs ont été essayées pour le nourrissage d'alevins de channel catfish placés dans 12 bassins en terre doublés de polyéthylène, où le niveau de l'eau était maintenu de manière à avoir une superficie de 0,0582 ha.

Les formules utilisées étaient les suivantes: 25 pour cent de protéines et 1.874 calories par kg (énergie métabolisable); 25 pour cent de protéines et 2.168 calories; 25 pour cent de protéines et 1.874 calories, mais teneur faible en protéines animales; enfin, 30 pour cent de protéines et 2.316 calories.

Avec les quatre formules on a obtenu des taux de conversion approchant de l'unité un kilo d'aliments par kilo d'alevins. Les 11.450 poissons utilisés pour l'expérience ont survécu dans la proportion de 95 17 pour cent.

Avec les poissons de classe d'âge II, petits et grands, placés ensemble ou séparément, il fallait légèrement plus de deux kilos d'aliments pour produire un kilo de poisson. Un écart initial d'un gramme dans le poids moyen des poissons donnait, en fin d'expérience, un écart de poids de 3,97 grammes.

Lors d'essais de descendance, on a obtenu, en déversant au mois de juin 170 g de fretin dans 6 étangs différents, des fingerlings pesant en moyenne de 10,6 à 19,5 grammes.

EXPERIMENTOS CON ALIMENTOS SUPLEMENTARIOS PARA EL BAGRE DEL CANAL

Extracto

Se alimentaron jaramugos del begre del canal con cuatro dietas de productos secos en 12 estanques de tierra revestidos de polietileno y en los que el nivel del agua se mantuvo a 0,0582 por hectárea de superficie.

Las dietas contenían: 25 por ciento de proteínas y 1.874 calorías por kg (energía metabolizable); 25 por ciento de proteínas y 2.168 calorías; 25 por ciento de proteínas y 1.874 calorías pero con escasas proteínas de origen animal; y 30 por ciento de proteínas y 2.316 calorías.

Con las cuatro dietas se logró un índice de conversión de un kg de alimento en un kg de pececillos. De los 11.450 peces sobrevivió el 95,17 por ciento.

Los peces grandes y pequeños de la clase II que se hallaban juntos o separados requirieron algo más de dos kg de alimentos para producir un kg de peces. Una diferencia de un gramo en el peso medio inicial entre los peces grandes y pequeños se tradujo en una diferencia de 3,97 gramos en el peso final.

En los ensayos de progenie, 170 g de jaramugos existentes en cada uno de los seis estanques durante el mes de junio produjeron pececillos pequeños de 10,6 a 19,5 gramos de peso medio.

1 INTRODUCTION

Swingle (1958) reported on experiments of growing channel catfish, Ictalurus punctatus, to marketable size by supplemental feeding with dry pelleted feeds. Tiemeier and Elder (1960) conducted studies on supplemental feeding of this fish. Tiemeier et al. (1964 and 1965) found a diet containing 25 percent protein and an energy to protein ratio of 34:1 as efficient as diets containing 30 and 35 percent protein. Nail (1962) and Tiemeier et al. (1965) found a sparing effect of carbohydrates on protein in comparing diets containing similar percentages of protein but different quantities of energy.

The present investigations were conducted to study growth and production of various sizes and stocking combinations of channel catfish when fed pelleted feeds.

Cooperating in the experiments were the Kansas State University Agricultural Experiment Station, Kansas Forestry, Fish and Game Commission, Federal Aid to Fisheries Project No. F-12-R-1 and Project No. 4-1-R-1 of the Bureau of Commercial Fisheries and U.S. Army Corps of Engineers.

2 METHODS AND EXPERIMENTS

Twelve nearly identical polyethylene-lined earthen ponds at the Tuttle Creek Fisheries Research Laboratory were stocked with 950 fingerling channel catfish each in April 1965. Beginning April 14, identical amounts of dry pelleted feed were supplied to fish in each pond till August 29. Four diets were given and each was supplied to fish in three randomly selected ponds. Fish were fed six days each week but not on the days they were weighed. Ten groups of five fish from a seining of several hundred fish were weighed at two-week intervals. Starting June 8, each pond was supplied an amount of feed equal to 4 percent of the total average weight of fish in all 12 ponds, based on the assumption that all fish stocked had survived. Adjustments in amount of feed were made every two weeks. Feeding ceased on August 29, and 20 groups of five fish were weighed from each pond on August 30. All fish were counted when removed during the next few days.

The various ingredients in four diets (Tables I and II) were calculated to provide:(Z-14) 25 percent protein and a metabolizable energy to protein ratio of 34:1; (Z-15) 25 percent protein and a ratio of 38:1; (Z-16) 25 percent protein but low in animal proteins and high in plant proteins with an energy ratio of 34:1; and (Z-17) 30 percent protein and an energy to protein ratio of 34:1.

Table I

Analyses of various diets, 1965

¹ Calculated from values in feed analyses tables
² Determined by AOAC methods
³ Contains low animal protein and high plant protein

Experimental formulae were calculated using a computer and the results were used in preparing diets by Kansas State University Department of Grain Science and Industry. Diets were prepared as 0.48 cm pellets and as granules for the fry fish.

Some channel catfish fed as fingerlings during 1964 were stocked in a farm pond during the winter of 1964–65. During April, this pond was seined and fish were classified as large if they weighed approximately 70 g or more and small if they weighed less. The left pelvic fin was clipped on large fish and the right pelvic fin on small fish. Fish were stocked in polyethylene-lined ponds.

Table II

Ingredients of various diets used in 1965 (in kg)

Various combinations of large and/or small fish were stocked in ponds as follows:

1. To determine effects on growth obtained by stocking an equal biomass of large and small fish; equal weights (3,405 g) of large and an equal weight of small fish was stocked in ponds Nos. 2 and 6. An identical amount of feed (Z-14) was supplied to fish in each pond. Fish were weighed at two-week intervals and removed in September.

2. To compare growth in ponds stocked with the same number of large or small fish but having different biomass, ponds Nos. 3 and 10 were each stocked with 179 large fish and ponds Nos. 8 and 12 with 179 small fish. Similar percentage of feed (4 percent daily of Z-14) was given daily to all fish but large fish in ponds 3 and 10 were fed more in total weight. Fish were weighed at two-week intervals.

On June 14, 170 g of newly hatched channel catfish from six different spawns were obtained from the Kansas Forestry, Fish and Game Commission hatchery. Each spawn was stocked in a separate pond. Granulated feed containing 35 percent protein was fed twice daily, seven days per week. An attempt was made to feed more feed than the fish would eat. After July 16, 5 percent of the total average weight of fish was supplied daily on the basis of 5,000 fish in each pond. Five groups of 10 fish were weighed at two-week intervals starting July 16. Fish were fed to October 1 when 10 groups of 10 fish were weighed. All fish were weighed and removed shortly after October 1.

Water temperatures were taken at 7 a.m. and 3 p.m. daily (Table III) at the surface and 1.37 metres depth in one pond. Extremely high and sudden temperature decreases were not encountered during the feeding period.

Table III

Average water temperature (°C) at 7 a.m. and 3 p.m. taken near the surface and at 1.37 m (pond No.1, 1965)

3 RESULTS

3.1 Fingerlings

Mean weight of 950 fingerling channel catfish was 2.32 g when counted and stocked in 12 ponds during April 1965. Data on stocking and recovery are presented in Table IV. Percentage gain in weight, gain per pond, rates of gain, conversions and feed costs are given in Table V. Weights of protein and kilocalorie content and their utilization by fingerling fish are presented in Table VI.

Table IV

Stocking and survival of fingerling channel catfish, 1965

Table V

Percentage gain in weight, gain per pond, rate of gain, conversion and feed cost for fingerlings, 1965

Table VI

Protein and kilocalories and their utilization by fingerlings, 1965

¹ Calculated from feed formula tables using metabolizable energy values

3.2 Age Class II fish

Six ponds were stocked with various numbers and total biomass of age class II fish (Tables VII and VIII). Data on survival are given in Table VII and those for gains in Table VIII. Table IX presents information on rates of conversion and utilization of protein and energy in the supplemental feed. A comparison of results obtained by stocking large and small age class II fish is given in Table X.

Table VII

Stocking and recovery of age class II fish, 1965

Table VIII

Stocking and recovery weights (in g) and gains of age class II fish, 1965 ¹

¹ Ponds were stocked with small, large or a combination of various sizes of fish

Table IX

Gain, conversion, cost, kilocalories and protein required to produce age class II fish and production rate per ha, 1965

¹ Z-14 feed, 25 percent protein, 1,874 calories per kg, cost U.S.$ 0.0968 per kg

² Pond 0.0792 surface ha, all others 0.0582

Table X

Growth (in g) obtained by stocking large and small age class II fish, 1965

3.3 Fry

Six lined ponds were each stocked with 170 g of newly hatched channel catfish on June 14. Fish stocked in each pond were from one spawn. Results of this experiment are given in Table XI.

Table XI

Production of channel catfish fry, 1965 ¹

¹ Stocked each 0.0582 surface ha pond June 14 with 170 g of newly hatched fish

Apparently the survival was very high and the experiment indicates the possibilities of rearing large numbers of fry to fingerlings by feeding with granulated feeds.

4 DISCUSSION

Variations in survival of fingerlings were greater in replicates of diets than between diets (Table IV). Mean survival in the 12 ponds was 95.2 percent compared to 96.8 percent obtained in 1964 (Tiemeier et al., 1965) when fish weighing 8 g were initially stocked.

A total gain of 897.3 kg or rate of gain of 74.8 kg per pond was obtained by stocking 11,450 fish averaging 2.32 g in 12 ponds in 1965. Tiemeier et al. (1965) obtained a total gain of 2,017.2 kg or a rate of gain of 126.2 kg per pond by stocking 32,000 fingerlings averaging 8 g in 16 ponds during 1964. Stocking 109.6 percent more fish per pond in 1964 produced an additional total weight gain per pond of 30.8 kg compared with 1965.

Rates of feed conversions were uniform and many conversions of less than 1.0 kg feed per kg of gain were calculated at the two-week weighing periods. Fish in all ponds were uniform in size.

Diets Z-14 and Z-16 were prepared to provide 1,874; Z-15:2,168 and Z-17:2,316 kcals per kg of feed. Kilocalories required to produce a kg of fish varied from 1,914.7 for diet Z-14 to 2,369.3 for Z-17 (Table VI). Phillips et al. (1963) concluded that trout could be reared on meat-meal mixtures at a rate of 4,628.4 kcals per kg of body weight. Kilocalories required in 1965 experiments on fingerlings were 50 percent of requirements in 1964 experiments (Tiemeier et al., 1965).

Proteins were efficiently utilized in all feeding regimes (Table VI). Those fish fed diet Z-14 required 259.69 to produce a kg of fish and greatest requirement was 316.5 g with diet Z-17 (30 percent protein). Sparing action of carbohydrates to save protein as reported by Nail (1962) and Tiemeier et al. (1965) was not evident. Diets Z-14 and Z-16, containing 1,874 kcals per kg were as efficient as Z-15 (2,168 kcals) and Z-17 (2,316 kcals). Diet Z-16, containing low animal protein was as efficient as diets Z-14 and Z-15 that contained more animal proteins.

Cost of diets (Table V) included retail price of ingredients, cost of processing and bagging. Diet Z-16 was cheapest because some plant proteins were substituted for animal proteins. Feed cost to produce a kg of fingerling fish varied from 0.095 U.S.$ for diet Z-16 to 0.107 for diet Z-15. Favourable water temperatures as indicated (Table III) facilitated excellent growth and conversions.

Ponds Nos. 2 and 6 were stocked with 3,405 g but different numbers of large and small fish (Table VII). Ponds Nos. 3 and 10 were each stocked with 179 large fish but ponds Nos. 8 and 12 were each stocked with 179 small fish. Survivals were excellent except for pond No.3 where lower percentage gain and comparatively fewer kg gain per ha were obtained (Table VIII).

Total gain by 491 small fish was almost identical with gain of 424 large fish (Table X). Large fish gained more weight per fish than small fish but percentage gain was greater for small fish. Wohlfarth et al. (1965) found that carp progenies with larger initial weights tend to show larger weight gains than progenies with lower initial weights. They found that one gram difference in initial weight was associated with three or four grams difference in weight gain. Fish in our experiments were from several progenies but our data indicated that a difference in initial weight of small and large fish of 28.6 g was associated with a difference of 113.6 g in final weights. From this, it can be observed that a difference of one gram in initial weight resulted in a difference of 3.97 g in final weight.

The weight of feed required to produce a kg of fish was 2.06 – 2.3 kg. Feed was more efficiently utilized in early summer and gradually decreased as fish increased in size. This probably indicated that the larger fish could not efficiently utilize 4 percent of their weight in daily feedings. Kilocalories and grams of protein required to produce a kg of fish (Table IX) were similar to those required by fingerling fish in 1964 experiments (Tiemeier et al. (1965) or twice the requirements for producing fingerlings in 1965 experiments.

5 REFERENCES

Nail, M.L., 1962 The protein requirement of channel catfish. Proc.Conf.stheast.Ass.Game Commrs., 16:307–16

Phillips, A.M. Jr., et al., 1963 The effect of diet mixture and calorie source on growth, mortality, conversion, and chemical composition of brook trout. Progr.Fish Cult., 25(1):9–14

Swingle, H.S., 1958 Experiments on growing fingerling channel catfish to marketable size in ponds. Proc.Conf.stheast.Ass.Game Commrs., 12:63–72

Tiemeier, O.W. and J.B. Elder, 1960 Growth of stunted channel catfish. Progr.Fish Cult., 22(4):172–76

Tiemeier, O.W., C.W. Deyoe and S. Wearden, 1964 Supplemental pellet feeding of channel catfish. Rep.Progr.Kans.Agr.Exp.Sta.

Tiemeier, O.W., 1965 Effects on growth of fingerling channel catfish of diets containing two energy and two protein levels. Trans.Kans.Acad.Sci., 68(1):180–6

Wohlfarth, F., et al., 1965 Activities of the carp breeders union in 1964. Bamidgeh, 17(1):9–15