PAUNCH MANURE AS A FEED SUPPLEMENT I N CHANNEL CATFISH FARMING

S. C . Yin*

INTRODUCTION

One of t h e most s e r i o u s problems faced by the meat-packing indus t ry i n a t tempt ing t o comply wi th t h e i n c r e a s i n g l y more s t r i n g e n t p o l l u t i o n con- t r o l r e g u l a t i o n s is t h e f ind ing of an accep tab le means t o d ispose of paunch manure from s laughtered catt le. The f e a s i b i l i t y of drying paunch manure and inco rpora t ing i t as a f eed supplement f o r t h e commercial pro- duc t ion of channel c a t f i s h w a s r epor t ed earlier (1, 2 ) . By so doing, i t would r e l i e v e the meat-packer from having t o d e a l wi th t h i s material as a probelm waste and t ransform i t i n t o a u s e f u l by-product. those pre l iminary f e a s i b i l i t y s t u d i e s , t he Environmental P r o t e c t i o n Agency awarded a g r a n t t o the Oklahoma S t a t e Univers i ty f o r i n v e s t i g a t i o n on a scale s imula t ing commercial e n t e r p r i s e s t o determine whether channel ca t - f i s h could b e grown on s p e c i a l l y formulated f eeds conta in ing var ious s u b s t i t u t i o n rates of d r i e d paunch manure a t growth rates ( i n one growing season) which would compare favorably wi th c o n t r o l f i s h g iven s tandard commercial c a t f i s h feed. t h i s completed p r o j e c t which w a s des igna ted EPA Grant No. R-800746 (12060 HVQ). prepa ra t ion f o r p r i n t i n g , and should be a v a i l a b l e f o r d i s t r i b u t i o n before long.

Following

This paper g ives a summary of t h e f ind ings of

The f i n a l r e p o r t on t h i s p r o j e c t is i n its f i n a l s t a g e s of

MATERIALS AND METHODS

Experimental Feeds

Two tons of d r i ed paunch manure w a s donated by Beefland I n t e r n a t i o n a l , Inc . This meat-packing company, l oca t ed a t Council B lu f f s , Iowa, w a s t h e rec ip- i e n t of another EPA g r a n t which d e a l t wi th the technology and economics of

*Environmental P ro tec t ion Agency, NERC,Corvallis, Robert S . Kerr Environmental Research Laboratory, Ada, Oklahoma 74820.

246

drying paunch and blood. That completed p r o j e c t w a s r epor t ed by Baumann (3). who con t r ac t ed t o supply t h e s tandard f e e d s and t o formulate t h e experi- mental f e e d s f o r t h i s p r o j e c t .

This d r i e d paunch w a s t r anspor t ed t o a commercial feed manufacturer

Table 1 shows t h e composition of t h e f eeds used. The f eeds w e r e formu- l a t e d i n such a manner t h a t a l l of them were e s s e n t i a l l y i son i t rogenous ( t h a t is, equa l i n p r o t e i n n i t r o g e n c o n t e n t ) and i s o c a l o r i c ( t h a t is, equa l i n c a l o r i c v a l u e pe r u n i t weight). pond-reared f i s h and t h e f l o a t i n g f eeds were f o r t h e caged f i s h . The o r i g i n a l p l a n w a s t o u s e f e e d s con ta in ing 20% and 30% paunch i n both pond and cage c u l t u r e s . Unfortunately, t h e p l a n t which produced t h e f l o a t i n g p e l l e t s w a s l o c a t e d near a r e s i d e n t i a l area. p r a c t i c a l l y odor l e s s , produced a h igh ly o b j e c t i o n a b l e odor when remoistened during t h e manufacturing process. For t h i s reason, t h e p l a n t manager, f e a r i n g complaints from t h e nearby r e s i d e n t s , r e fused t o proceed f u r t h e r a f t e r f i n i s h i n g t h e ba t ch con ta in ing 10% paunch. Anyone who has experi- enced t h e odor of f r e s h , w e t paunch manure can e a s i l y sympathize wi th that dec i s ion . it may become a n important f a c t o r i n l i m i t i n g i t s adopt ion by t h e f eed i n d u s t r y f o r i nco rpora t ion i n t o f eed of any kind.

The s i n k i n g f e e d s were f o r t h e

Dried paunch, which is

Unless t h i s undes i r ab le q u a l i t y of paunch can be overcome,

Table 1. Composition (%) of Commercial C a t f i s h Feeds, Sinking Feeds Containing by Weight 10-30% Paunch, and a F loa t ing Feed Containing 10% Paunch

F l o a t i n g f eeds Sinking f e e d s Ing red ien t Commercial 10% Commercial 10% 20% 30%

Pro te in , Kjeldahl 38.6 38.7 32.2 34.9

Fa t , e t h e r e x t r a c t 3.3 3.1 4.6 3.7

F ibe r 5.8 5.1 7.9 8.3

Calcium 1.22 1.32 0.42 0.53

Phosphorus 0.93 1.13 0.98 0.85

Calories, KC/G 4.16 4.25 4.15 4.28

33.5

3.7

10.2

0.57

0.75

4.34

33.1

3.7

10.7

0.67

0.73

4.32

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Fish Cul tures

The layout of t h e ponds cons t ruc ted f o r t h i s p r o j e c t i s shown i n Figure 1. The s i z e of the ponds used f o r pond c u l t u r e s w a s 0.1 h e c t a r e each, and t h e cage c u l t u r e ponds w e r e 0.4 h e c t a r e each. Ponds 6 and 1 0 w e r e c o n t r o l ponds f o r water q u a l i t y monitoring, i n which t h e r e were no f i s h s tocked, and no feed of any kind w a s added t o t h e s e two ponds during t h e course of t h e experiment. The cages used w e r e cons t ruc ted of aluminum frame and vinyl-coated w i r e mesh, each measuring 0.91m t a l l , 0.91m wide, and 1.37m long. They were buoyed wi th Styrofoam s o t h a t a submerged depth of 0.81m wi th a water volume of l.0m3 w a s obtained. t e t h e r e d t o a p i e r i n each of t h e two cage c u l t u r e ponds.

These cages were

The s i z e and number of f i n g e r l i n g s chosen t o s t o c k t h e ponds and cages were planned t o s imula t e average commercial y i e l d (kg/ha) wh i l e ob ta in ing an " ideal" market s i z e f i s h wi th in a 168-day growing season. I n consid- e r i n g t h e s e o b j e c t i v e s , a number of a u t h o r i t a t i v e pub l i ca t ions wi th varying viewpoints (4, 5, 6, 7, 8, 9) w a s consul ted before t h e fol lowing dec i s ions were made:

(a) I n t h e pond c u l t u r e s , each 0.1-ha pond w a s s tocked wi th 269 f i n g e r l i r g s of 70g each. This s tocking d e n s i t y (2600/ha) w a s considered maximum c o m e n s u r a t e wi th the b a s i c o b j e c t i v e of a y i e l d of about 1408 kg and a f i n a l average weight of 568 g. Assuming a m o r t a l i t y rate of 4%, t h e number of f i s h s tocked i n each pond w a s t e n more than t h e number expected t o su rv ive t h e i n v e s t i g a t i v e per iod.

(b) Each of t h e t h r e e cages i n each of t h e 0.4-ha ponds w a s s tocked wi th 345 f i n g e r l i n g s of t h e same s i z e as used i n t h e pond c u l t u r e s . This s tock ing dens i ty (2587/ha) w a s s e l e c t e d no t only t o be c o n s i s t e n t w i th commercial p r a c t i c e as recommended by top r e sea rche r s i n t h e f i e l d , bu t a l s o t o d u p l i c a t e t h e d e n s i t i e s i n t h e pond c u l t u r e s , so t h a t t h e w a s t e loading from t h e f i s h and from uneaten feed i n both types of c u l t u r e ponds would be expected t o be equal . Thus, comparison of t h e e f f e c t s on water q u a l i t y between t h e two c u l t u r a l methods would be more meaningful.

The d a i l y r a t i o n of feed given t o t h e f i s h i n a l l ponds w a s based on an average of t h r e e percent of t h e body weight. For t h i s purpose, samples of f i s h from each pond and each cage were taken every 28 days and t h e f i s h w e r e anes the t i zed f o r l eng th and weight measurements.

Water Q u a l i t y Analyses

One j u s t i f i a b l e concern of u t i l i z i n g paunch as a f i s h feed c o n s t i t u e n t i s its p o t e n t i a l as a water p o l l u t a n t . S ince f r e s h paunch has a h igh bio- chemical oxygen demand (BOD), over e igh ty percent of which w a s found i n t h e water s o l u b l e f r a c t i o n (1, 2) , i f feed con ta in ing d r i e d paunch is not

248

,

' I

1 : ... .. . . .- . . .. . . , . *. . . L:

. . -i . ' I ._ . ?$ ./.. f . ' ., . . .. . - c.;

.'-i

5 : i : ... , :. .! ..\ .. ..- i' I._.

.* ! ... : : :< ... I.

i ' ._ . :. : ' I r . f.

..

... !., f, .. c .. . .. .- .

., < + .1

POND NO.

11,15 9,12

13,16 5, 7 8, 14

CAGE NO.

31,32,33 21,22,23

Figure 1. Experimental f i s h ponds used i n pond (5-16) and cage c u l t u r e (2 and 3) c v p c r i n e n t s . The t a b u l a r iriset b e s c r i b e s the e x p e r i m e n t a l desigrl. T h c caees u s e d i n ponds 2 and 3 are- sho . *~ with [ 3 .

249

- ea ten by t h e f i s h wi th in a reasonably s h o r t t i m e a f t e r t h e feed is i n t r o - duced i n t o t h e w a t e r , t h e paunch i n t h e feed could very w e l l become a s e r i o u s water p o l l u t a n t . Therefore , i t w a s decided t o monitor t h e water q u a l i t y of t h e ponds during t h e course of t h e i n v e s t i g a t i o n t o see i f t h i s f e a r i s indeed a r e a l i t y and l e a d s t o a problem which would preclude t h e use of paunch f o r t h i s purpose.

Because of t h e sho r t age of funds and manpower, i t w a s no t p o s s i b l e t o monitor a l l of t h e ponds. The ponds s e l e c t e d f o r w a t e r q u a l i t y monitoring were t h e fol lowing:

(a) Ponds 6 and 10, which were t h e two c o n t r o l ponds i n which no f i s h w e r e s tocked and where no feed of any type w a s added t o t h e water during t h e whole 168-day per iod.

(b) Ponds 2 and 3, which w e r e t h e cage c u l t u r e ponds. The f i s h i n pond 2 rece ived feed conta in ing 10% paunch, whi le those i n pond 3 received s tandard commercial feed .

(c) Ponds 9 and 12, which were t h e r e p l i c a t e ponds i n t h e pond c u l t u r e where t h e f i s h received s tandard commercial feed.

(d) Ponds 8 and 14, which were t h e r e p l i c a t e ponds i n t h e pond c u l t u r e where t h e f i s h rece ived feed conta in ing t h e h ighes t p ropor t ion of paunch--30%.

This p a r t of t h e inves t iga t ion- - the water q u a l i t y studies--was a coopera- t i v e e f f o r t between Oklahoma S t a t e Univers i ty and ETA'S Robert S. Kerr Environmental Research Laboratory. A t o t a l of seventeen parameters w a s included i n t h e ana lyses . These were pH, d isso lved oxygen, temperature , carbon d ioxide , biochemical oxygen demand (>day), chemical oxygen demand, t o t a l o rgan ic carbon, ammonia, t o t a l Kje ldahl n i t rogen , n i t r i t e , n i t r a t e , t o t a l phosphate, orthophosphate, t o t a l s o l i d s , t o t a l suspended s o l i d s , v o l a t i l e suspended s o l i d s , and f e c a l col i forms. Samples w e r e c o l l e c t e d weekly by O.S.U. personnel who a l s o measured t h e f i r s t f o u r parameters l i s t e d above a t t h e s i t e of t h e ponds. s e p a r a t e samples t h a t w e r e t aken a t d i f f e r e n t t i m e s dur ing t h e d a y l i g h t hours of t h e sampling day. Once every fou r weeks, however, both pooled daytime and n ight t ime samples were taken. For those ana lyses t h a t were not performed a t t h e s i t e of t h e ponds, t h e samples were iced and t r ans - ported t o t h e Kerr Laboratory i n Ada, Oklahoma, where t h e ana lyses were done.

Each sample w a s pooled from t h r e e

RESULTS AND DISCUSSION

The d e t a i l s of a l l t h e d a t a obtained i n t h i s i n v e s t i g a t i o n and t h e s t a t i s t i c a l ana lyses of t h e s e d a t a w i l l no t be presented h e r e i n t h e s h o r t t i m e ava i l ab le . Those who are i n t e r e s t e d i n t h e s e d e t a i l s w i l l be a b l e

250

t o s tudy them i n t h e f i n a l p r o j e c t r e p o r t which w i l l soon be a v a i l a b l e . Only t h e s a l i e n t p o i n t s of t h e f ind ings w i l l be given i n t h i s p re sen ta t ion .

Table 2 shows t h e y i e l d s of t h e pond-reared f i s h a t t h e end of t h e 168-day growing season which was terminated on November 2, 1972. Yield is def ined as t h e biomass of f i s h p re sen t a t the t i m e of ha rves t ; i .e . , when t h e pond w a s d ra ined . Ponds 11 and 15 were t h e ponds i n which t h e f i s h were no t

Table 2. Yield of Channel C a t f i s h on November 2 from 0.1 ha Ponds and Amount of Feed Added During t h e 168-day Growing Seasona

Treatment Pond

Yield/ponds kg

Amount (kg) Feed added

Standard feed

9b 12 . Avg.

Feed wi th 10% paunch

1 3 1 6 Avg.

Feed wi th 20% paunch

5 7

Avg . Feed wi th 30% paunch

8 1 4 Avg .

N o supplemental feed

11 15 Avg .

147.60 110.42 129.01

123.96 132.73 128.35

120.25 126.50 123.38

104.16 109.91 107.04

16.78 21.85 19.32

201.88 215.45 208.66

211.90 223.02 217.46

216.62 190.95 203.79

178.72 187.02 182.87

0 0 0

~

aYield t i m e s 10 = y i e l d l h a

bA 13% loss of f i s h due t o poaching accounts f o r t h e low y i e l d .

2 51

given any supplemental feed but l i v e d only on whatever n a t u r a l food they were a b l e t o f i n d i n t h e pond. The average y i e l d of t h e s e two ponds w a s only 15.7% of t h e average y i e l d of t h e o t h e r e i g h t ponds where supple- mental food w a s given. Average y i e l d s f o r ponds 9 and 12 (s tandard f e e d ) , f o r ponds 1 3 and 16 (10% paunch), and f o r ponds 5 and 7 (20% paunch) w e r e q u i t e s imi l a r , as were t h e average amount of feed added. The average y i e l d of ponds 8 and 14 (30% paunch), however, w a s s i g n i f i c a n t l y lower. But i t w a s a l s o noteworthy t h a t t h e amount of feed added, which w a s based on t h e average weight of t h e f i s h sampled every 28 days, w a s a l s o s i g n i f i - c a n t l y lower than those added t o t h e o t h e r ponds. Because s lower growing f i s h would, t h e r e f o r e , be fed less food, i t is p o s s i b l e t h a t y i e l d merely r e f l e c t s t h e t o t a l q u a n t i t y r a t h e r than t h e q u a l i t y of t h e food ea t en .

Table 3 shows t h e mean cond i t ion f a c t o r , mean length , and mean weight of t h e f i s h r ece iv ing d i f f e r e n t t rea tments . Again, t h e means f o r t h e f i s h i n t h e pond c u l t u r e s where s tandard feed, feed with 10% paunch, and feed wi th 20% paunch w e r e used w e r e e s s e n t i a l l y equal , whereas those f o r t h e f i s h which were given feed conta in ing 30% paunch w e r e s i g n i f i c a n t l y lower. I n t h e cage c u l t u r e s , t h e t h r e e means f o r t h e f i s h given feed conta in ing 10% paunch were s i g n i f i c a n t l y lower than those given s tandard commercial feed, and t h e means of t h e f i s h i n both of t hese cage c u l t u r e s were s i g n i f i c a n t l y lower than those i n t h e pond c u l t u r e s . F ish confined i n cages are unable t o supplement t h e i r d i e t w i th n a t u r a l food p resen t i n t h e pond. Hence, d e f i c i e n c i e s i n t h e feed ing red ien t s are a p t t o be more pronounced than f o r pond-reared f i s h . Also, f o r t h i s same reason, i t i s expected t h a t f i s h i n pond c u l t u r e s given t h e same kind and q u a n t i t y of food as f i s h reared i n cages w i l l show a f a s t e r and g r e a t e r growth rate.

However, i n s p i t e of azslower growth rate shown by t h e caged f i s h as com- pared t o t h e pond-cultured f i s h , t h e caged f i s h i n both ponds (s tandard feed and 10% paunch feed) showed b e t t e r feed conversion than t h e pond- cu l tu red f i s h , r e g a r d l e s s of t h e type of feed, as shown i n Table 4 . The "S" conversion f a c t o r is obta ined by d iv id ing t h e weight i n kilograms of feed added by t h e weight ga in i n kilograms, whi le t h e "C" conversion f a c t o r i s obtained by d iv id ing t h e weight i n kilograms of feed added by t h e ad jus t ed weight ga in , which is t h e weight ga in i n kilograms minus t h e weight ga in i n kilograms expected i f t h e f i s h had not been given any supplemental feed. This l a s t weight gain, of course, is obtained from t h e weight ga in shown by t h e f i s h i n t h e c o n t r o l ponds 11 and 1 5 which l i v e d only on t h e n a t u r a l food they could f i n d i n t h e ponds. weight ga in i n t h e s e two ponds w a s 2.37 kg per pond. Thus, t h e smaller t h e conversion f a c t o r , t h e b e t t e r i s t h e feed conversion. Also, s i n c e t h e "S" f a c t o r inc ludes weight ga in due t o n a t u r a l foods, and s i n c e caged f i s h are p r a c t i c a l l y t o t a l l y dependent on supplemental food, i n comparing feed conversion between pond-reared f i s h and cage-reared f i s h , i t would be more accu ra t e t o compare t h e "C" f a c t o r of t h e former with t h e "S" f a c t o r of t h e la t ter .

The average

Table 5 shows t h e comparative c o s t s of producing c a t f i s h us ing s tandard commercial f eeds and f eeds con ta in ing var ious l e v e l s of paunch. The

252

-

Table 3. Mean Condition Fac tor (K ), Length, and Weight of Pond-Reared (TRTS 1 - 5 ) and Cage-Rear:$ (TRTS 6 + 7 ) Channel C a t f i s h on May 1 8 and November 2

TRT Feed, Pond and Cage No. No. i n ( )

May 1 8 November 2

None (11 + 1 5 )

Std. s i n k i n g ( 9 + 1 2 )

10% paunch ( 1 3 + 1 6 )

20% paunch ( 5 + 7 )

30% paunch ( 8 + 1 4 )

Std. f l o a t i n g ( 3 1 , 32 , 3 3 )

1 0 % paunch ( 2 1 , 2 2 , 2 3 )

0 .66 212.6

65.2

0 . 6 6 218.9

71.2

0.67 212.8

66.4

0.70 216.4

71 .4

0.67 219.7

72.5

0.66 202.0

57.7

0.68 227.0

82.8

0.67 227.0

80 .4

0.94 385.6 547.4

0.86 388.4 507.4

0.87 384.2 502.7

0 .84 367.2 419.0

0.97 335.5 360.2

0.93 321.7 313.2

253

Table 4 . Channel C a t f i s h Conversion Fac tors of F i s h Reared i n Ponds Given a Standard Commercial Feed o r Feeds Containing 10, 20, and 30% Paunch, and Conversion Fac tors of Cage-Reared F i sh Given a Standard Feed o r Feed wi th 10% Paunch

Conversion f a c t o r Treat men t Feed Weight g a i n (kg)

pond added (kg) To ta l Adjusted S C

Std. feed Pond 9 Pond 12 TRT Avg.

1OX paunch Pond 1 3 Pond 16 TRT Avg.

20% paunch Pond 5 Pond 7 TRT Avg.

30% paunch Pond 8 Pond 14 TRT Avg.

S t d . feed Cage 32 Cage 33 TRT Avg.

10% paunch Cage 22 Cage 23 TRT Avg.

201.88 215.45 208.66

211.90 223.02 217.46

216.62 190.52 203.57

178.72 187.02 182.87

153.53 147.08 150.30

124.87 118.04 121.45

PONDS

128.10 92.87

110.48

105.76 116.38 111.07

101.69 106.94 104.32

84.66 91.71 88.18

CAGES

94.72 139.08 116.90

84.80 75.74 80.27

125.73 90.50

108.12

103.39 114.01 108.70

99.32 104.57 101.94

82.29 89.32 85.82

1.58 1.60 2.32 2.38 1.89 1.93

2.00 2.05 1.92 1.96 1.92 2.00

2.13 2.18 1.79 1.82 1.78 2.00

2.11 2.17 2.04 ,2.09 2.07 2.13

- 1.62 - - 1.06 - - 1.28 -

- 1.47 - - 1.56 - - 1.51 -

254

Table 5. Comparative Feed Costs t o Produce Channel C a t f i s h Using t h e Standard Feeds and Feeds wi th Various Levels of Paunch

Cu l tu re System feed type

Conversion Cost of feed $ /kq Cost of f eed S C

S C $/kg f a c t o r

Pond Culture-Sinking Feed

Standard commercial 0.106 1.89 1.93 0.20 0.20

Feed wi th 10% paunch 0.104 1.92 2.00 0.20 0.21

Feed wi th 20% paunch 0.115 1.78 2.00 0.20 0.23

Feed wi th 30% paunch 0.137 2.07 2.13 0.28 0.29

Cake Culture-Float ing Feed

Standard commercial 0.176 1.28 - 0.22 - Feed wi th 10% paunch 0.178 1.51 - 0.27 -

comparisons w e r e based on p r i c e s e x i s t i n g a t t h e t i m e t h e study w a s i n i t i a t e d , i.e., March 1972. Cost of dehydrated paunch w a s es t imated t o be $22.05 pe r metric ton, f.o.b., Omaha, Nebraska. For t h e s ink ing f eeds used i n pond c u l t u r e s , t h e only experimental feed con ta in ing paunch t h a t d i d no t c o s t more than t h e s tandard commercial feed t o produce t h e same weight of f i s h w a s t h e 10% paunch-containing feed. percentages of paunch c o s t more because t o make t h e f eeds isoni t rogenous ( i .e . , having t h e same p r o t e i n con ten t as t h e s t anda rd commercial f e e d ) more h ighe r p r i ced , high p r o t e i n c o n s t i t u e n t s such as f i s h and soybean meals have t o be added t o make up f o r t h e p r o t e i n de f i c i ency of paunch. I n t h e cage c u l t u r e s , t h e c o s t t o produce one kilogram of f i s h wi th f l o a t i n g feed con ta in ing 10% paunch w a s considerably higher than t h e c o s t using s t anda rd commercial feed. Unless t h e saving t o t h e meat-packer i n not having t o treat t h e paunch as a w a s t e is taken i n t o cons ide ra t ion , i t would not be economical t o raise channel c a t f i s h by inco rpora t ing more than 20% paunch i n t o t h e feed i n pond c u l t u r e , and any a t a l l i n cage c u l t u r e . Nevertheless , w i th more s t r i n g e n t waste d i scha rge r e g u l a t i o n s f a c i n g t h e meat indus t ry , t h i s saving may become a n important c o n s i d e r a t i o n t h a t should not be overlooked i n cons ide r ing t h e cos t .

Feeds con ta in ing higher

255

The d a t a obtained i n t h e water q u a l i t y s t u d i e s revealed t h a t t h e s ink ing f eed con ta in ing 30% paunch and t h e f l o a t i n g feed con ta in ing 20% paunch did not have any s i g n i f i c a n t adve r se e f f e c t s on t h e water q u a l i t y as com- pared t o s tandard commercial feed. Moreover, a l though t h e water q u a l i t y of a l l t h e ponds i n which f i s h were kept i n t h i s i n v e s t i g a t i o n had d e t e r i o - r a t e d t o some degree by t h e end of t h e 168-day pe r iod , t h e d e t e r i o r a t i o n i n none of t h e parameters measured w a s s u f f i c i e n t l y g r e a t t o have caused concern. I n a l l ponds, f r e s h water w a s added as needed t o maintain a cons t an t w a t e r level. S t a t i s t i c a l ana lyses of t h e d a t a showed t h a t under t h e experimental cond i t ions descr ibed which were designed t o s imula t e commercial production, t h e water q u a l i t y of a l l t h e ponds--both pond and cage cultures--had n o t d e t e r i o r a t e d t o any apprec iab le degree i n t h i s one growing season. of as high as 30% d r i e d paunch i n s ink ing feed and 10% i n f l o a t i n g f eed f o r t h e product ion of channel c a t f i s h w i l l not cause any g r e a t e r w a t e r p o l l u t i o n than t h e u s e of s tandard commercial feeds.

I n t h i s s tudy, i t w a s demonstrated t h a t i nco rpora t ion

CONCLUSIONS

It is f e a s i b l e t o use dehydrated paunch as a f eed c o n s t i t u t e n t i n formu- l a t e d f eeds f o r pond-rearing channel c a t f i s h . can be used without producing a s i g n i f i c a n t r educ t ion i n growth as com- pare'd t o f i s h r ea red on a t y p i c a l commercial feed. Economically, l e v e l s of paunch up t o 20% may be used without i n c r e a s i n g the feed c o s t s pe r kg of f i s h f l e s h produced. Thus, paunch is economical as a feed c o n s t i t u e n t i n formulated f eeds f o r pond-rearing of channel c a t f i s h up t o a 20% level. For cage c u l t u r e , however, paunch a t 10% s u b s t i t u t i o n level would not produce a d e s i r a b l e economic r e t u r n , and only smaller amounts may be used. The f i s h ha rves t obtained i n t h e p r e s e n t s tudy averaged 1219 kglha. t h i s d e n s i t y none of t h e water q u a l i t y parameters l i m i t e d growth o r pro- duction. There w a s no evidence t h a t a t product ion l e v e l s t y p i c a l of average commercial c a t f i s h farming t h a t metabolic wastes have a nega t ive feedback on f i s h growth o r production.

Under t h e experimental cond i t ions of t h e p re sen t study which endeavored t o s imula t e t y p i c a l c a t f i s h farming techniques, f i s h c u l t u r e d i d no t cause apprec i ab le water q u a l i t y d e t e r i o r a t i o n i n one growing season. t h e r e w a s no s i g n i f i c a n t d i f f e r e n c e i n water q u a l i t y between ponds using a t y p i c a l commercial f eed and a f eed con ta in ing dehydrated paunch. similar d e n s i t i e s , t h e r e w a s no d i f f e r e n c e i n water q u a l i t y between ponds using cage- and pond-rearing techniques.

Levels of 10 t o 20% paunch

A t

Moreover,

A t

256

REFERENCES I-

1. Yin, S . C . , R. C. Summerfelt, and A. K. Andrews. 1 9 7 2 . Dried c a t t l e ” paunch manure as a feed supplement f o r channel c a t f i s h , p. 75-82. I n

Proc. 23rd. Okla. Ind. Waste and Advance Waste Conf., A p r i l 3-4, 19=, Oklahoma S t a t e Un ive r s i ty , S t i l l w a t e r , Oklahoma.

2. Yin, S. C. and J. L. Witherow. 1972. Ca t t l e paunch con ten t s as f i s h feed supplement: f e a s i b i l i t y s t u d i e s , p. 401-408. &I Proc. 3rd. N a t . Symp. on Food Processing Wastes, Mar. 28-30, 1972, New Orleans, Louis iana (EPA Pub. No. EPA-R2-72-018).

3. Baumann, D. J. 1971. El imina t ion of water p o l l u t i o n by packinghouse animal paunch and blood. EPA Pub. No. 12060 FDS 1 1 / 7 1 .

Water P o l l u t i o n Control Research S e r i e s .

4 . Bureau of Commercial F i she r i e s . 1970. A program of r e sea rch f o r t h e c a t f i s h farming indus t ry . U. S. Dept. Commerce, Economic Development Adm., Tech. A s s i s t . P ro j . XIII. 216 p.

5. Bureau of Spor t F i s h e r i e s and Wi ld l i f e . 1970. Report t o t h e f i s h farmers . U. S. Gept. I n t e r i o r , Bureau of Spor t F i s h e r i e s and Wi ld l i f e , Resource Pub. No. 83, 124 p.

6. Meyer, F. P. 1969. Where do w e s t and? , p . 8-11. - In Proc. 1969 F i sh Farming Conf., Texas Agr. Ext. Serv. , Texas A&M Univ., Col lege S t a t i o n , Texas.

7. C o l l i n s , R. A . 1970. Cage c u l t u r e of c a t f i s h : r e sea rch and p r i v a t e e n t e r p r i s e . C a t f i s h Farmer 2(4):12-17.

8. L e w i s , W. M. 1970. Suggest ions f o r r a i s i n g channel c a t f i s h i n f l o a t i n g cages. Laboratory, Southern I l l i n o i s Univ., Carbondale. 5 p.

Unpublished m n l t i l i t h r e p o r t of F i s h e r i e s Research

9. Schmittou, H. R. 1970. Developments i n t h e c u l t u r e of channel

f

c a t f i s h , I c t a l u r u s puncta tus (Rafinesque), i n cages suspended i n ponds. Proc. S. E. Assoc. G a m e & F i s h Com. 23(1969): 226-244.

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