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Effect of Processing Methods and Amino Acid Supplementation on Dietary Utilization of Feather Meal Protein by Chicks1
Effect of Processing Methods and Amino Acid Supplementation on Dietary Utilization of Feather Meal Protein by Chicks 1 E D W A R D C . N A B E R A N D S. P .
TOUCHBURN
Department of Poultry Science, Ohio State University, Columbus 10, Ohio AND B . D . B A R N E T T A N D C. L .
MORGAN
Department of Poultry Husbandry, South Carolina Agricultural Experiment Station, Clemson, South Carolina (Received for publication November 3, 1960)
INTRODUCTION
T
HE keratin proteins have generally been considered to be of little nutritive value because of their chemical structure which makes them insoluble and poorly digestible. Early attempts to use powdered sources of keratin as dietary protein were only slightly successful even when amino acid supplements were provided to offset the deficiencies of these proteins. Routh (1942) reported that powdered chicken feathers, as the sole source of protein for rats, were capable of supporting a moderate growth rate only when supplemented by tryptophan, methionine, histidine and lysine. Balance experiments conducted by Mangold and Dubski (1930) failed to show any digestion of white goose feathers by cats and owls. Thus it appeared that native feather keratin was not only seriously deficient in certain amino acids but was also poorly digestible. The development by Binkley and Vasak (1950) of a method for processing feathers into a friable, high density meal stimulated new investigation of the nutritive value of feather keratin.
It is apparent from the experimental findings of Wilder et al. (1955), Lillie et al. (1956), Naber and Morgan (1956), Wisman et al. (1958) and McKerns and Rittersporn (1958) that commercial feather meal, processed by the steam cooking method, can be utilized by the chick as a source of dietary protein, certain vitamins and unidentified growth factors. The degree to which feather meal protein can be utilized by the chick still remains in doubt. In addition, no evidence that processing conditions alter utilization of protein from feather meal was found by Sullivan and Stephenson (1957). Since feathers from poultry slaughter plants often undergo fermentation prior to processing and are contaminated with blood and offal, it is difficult to determine the true nutritive properties of processed feather protein. Finally, the amino acid deficiences of steam cooked feather meal have not been studied extensively. The experiments reported here deal with the effect of feather processing conditions or methods and amino acid supplementation of feather meal on chick growth, feed utilization and nitrogen retention.
1
Published with approval of the Directors of the Ohio Agricultural Experiment Station and the South Carolina Agricultural Experiment Station. Presented in part at the Annual Meeting of the American Institute of Nutrition in April, 1959 at Atlantic City, New Jersey.
EXPERIMENTAL
Day-old meat-type chicks were wingbanded for identification, vaccinated intranasally for Newcastle disease and
1234
1235
FEATHER MEAL PROCESSING AND SUPPLEMENTATION TABLE 1.—Basal rations i
I in experiments Ration No.
Major ingredients (grams per kilogram) Ground yellow corn Sucrose Refined corn oil Soybean oil meal (44% protein) Soybean oil meal (50% protein) Defluorinated rock phosphate (31% calcium and 18% phosphorus) Ground limestone (38% calcium) Iodized salt (0.007% iodine) Manganese sulfate (27% manganese) Salts mixture* Choline Chloride • Minor ingredients (units per kilogram) Vitamin A, U.S.P. units Vitamin Da, I.C. units DL alpha tocopherol acetate, mgs. 2 methyl 1,4-naphthoquinone, mgs. Thiamine, mgs. Riboflavin, mgs. Calcium pantothenate, mgs. Niacin, mgs. Pyridoxine, mgs. Folacin, mgs. Biotin, mgs. Cyanocabalamin, megs. Para amino benzoic acid, mgs. Procaine penicillin, mgs. Chlorotetracycline, gms. Percent crude protein content Composition of salts mixture CaCOs K2HPO4 CaHPCv2H 2 0 NaCI MgS0 4 -7H 2 0 Fe Citrate-6H 2 0 MnSCvH20 KI CuS0 4 -5H 2 0 ZnCl 2
600
660
— —
498 55
360
— —
300
—
—
385
20 IS 5 0.22
20 IS 5 0.44
—
—
— — —
1.1
,200 600
—
1.1
—
4.4 11.0 44.0
— — —
9.9
— —
10.0 21.2
1.1
8,800 1,320 8 1.1 2.2 7.7 15.4 44.0 4.4 4.4 0.22 26.4
— —
10.0 20.0
—
60 2.0
10,000 2,000 10 0.5 10.0 6.0 20.0 50.0 4.0 4.0 0.22 20.0 100.0 10.0
—
20.0
3,803.2 2,580.0 1,190.0 1,340.0 816.0 220.0 40.0 6.4 2.4 2.0 10,000.0 parts
infectious bronchitis and reared in electrically heated batteries with raised wire floors. Ten to 20 chicks were used in each experimental group with the sexes equally represented. Feed and water were supplied ad libitum. When experiments were conducted beyond four or five weeks of age, birds were transferred to standard growing batteries. Records of body weight, feed consumption and mortality were maintained.
In most experiments, body weight data were subjected to the analysis of variance. When statistically significant differences between treatment means were found by application of the F test, Duncan's multiple range test was used to determine the significance of differences among the experimental treatments. In the tables, treatment averages which differ significantly (p<.05) have superscripts of different letters. Treatment
1236
E. C. N A B E E , S. P. TOUCHBTJRN, B. D. B A R N E T T AND C. L.
MORGAN
TABLE 2.—A comparison of commercially processed feather meeds on growth, feed conversion and nitrogen retention of chicks. Experiment 1 Data on feather meal sampl es Supplement to basal Ration 1 plus 0.05% DLmethionine1 None Feather Meal 5 Feather Meal 6 Feather Meal 7 Feather Meal 8 Feather Meal 9 Feather Meal 10 Feather Meal 11 Poultry By Product Meal2 2 % Fish Meal and 2% whey 1
% pepsin digestibility of meal
Av. body wt.3 at 8 wks (grams)
Feed .% conversion nitrogen4 (grams feed retained per gm. gain)
Manufacturer
Fermentation step prior to processing
—
—
—
A B B C C D E
No No Yes No Yes No Yes
51 59 82 57 59 65 60
13.4 13.5 14.2 13.8 13.0 13.9 14.0
1,174*5 1,123" l,096 b 1,136" 1,134" 1,155" 1,144" 1,157"
2.26 2.19 2.23 2.28 2.19 2.22 2.20 2.21
52.3 59.1 57.3 56.1 60.1 60.5 57.5 54.4
—
—
—
__
1,242°
2.27
52.7
—
—
—
—
1,194"
2.28
53.8
%
nitrogen in meal
Feather meals and poultry by-products meal used in quantities to furnish 5% protein in experimenta1
diet. 2
Composed of feathers, blood and offal in naturally occurring proportions. Duplicate groups of 20 chicks each per treatment. During a four day test period after the chicks were three weeks of age. £ Treatment averages that are significantly different ( P < .05) from each other bear different superscript letters. 3
4
averages bearing the same superscript letter are not significantly different (p>.05). In some experiments, nitrogen retention was measured. Retention was calculated from the difference between total nitrogen intake and total nitrogen excretion. Feces were collected by placing trays containing one normal sulfuric acid under the wire floors of a metabolism cage for a 96 hour period. Fecal markers (Sudan Red I I I in gelatin capsules) were employed to indicate the beginning and end of each collection period. Fecal homogenates and feed samples were analyzed for Kjeldahl nitrogen and calculations of retention were made. Composition of the basal experimental rations is shown in Table 1. Rations 1 and 2 are semi-practical corn-soybean oil meal rations. Ration 2 contains less crude protein and more vitamin fortification than does Ration 1. Ration 3 is a semipurified ration utilizing 50 percent protein soybean oil meal as the sole protein
source. Feather meal and other protein feedstuffs were isonitrogenously substituted in these basal rations with adjustments in the soybean oil meal and corn or sucrose levels. In several experiments, the protein level of Ration 3 was reduced to 12 percent by adjusting the ratio of sucrose to soybean oil meal or feather meal. Amino acid supplementation levels used in these experiments were based on calculated deficiencies in the rations. Calculations were made from data on amino acid composition of feather meal published by Gregory et al. (1956) and Davis (1958). Summary data on amino acid composition published by Block and Boiling (1951) was used for other protein feedstuffs. Based on requirements for amino acids published by the National Research Council (Bird et al., 1954), it appeared t h a t feather meal supplied less than the required amounts of lysine, histidine, methionine, tryptophan and possibly phenylalanine. In addition, the
FEATHER MEAL PROCESSING AND SUPPLEMENTATION
amount of arginine supplied by feather meal was very near the stated requirement. A series of commercial and laboratory processed feather meal samples was tested during the course of this work. Seven commercially processed samples including three samples that had been fermented prior to processing were employed. Laboratory processed meals were prepared from clean unfermented feathers. Processing consisted of steam pressure cooking of feathers under several conditions of pressure and time. Untreated raw feathers were used as controls. All samples were dried at 140°F. and ground to produce a free flowing meal. In vitro pepsin digestibility of feather meal samples was determined by the method described by Gehrt et al. (1955) as modified by Elmslie (1958). RESULTS AND DISCUSSION
Preliminary work showed that four samples of commercial feather meal previously tested by Naber and Morgan (1956) were capable of supplying onequarter of the protein in chick starting rations. Since these samples represented only two commercial sources of the product, it appeared desirable to compare a variety of feather meal sources to determine whether or not commercial sources vary in their ability to replace 5 percent of protein in basal ration 1. Thus an experiment was conducted to test seven feather meal samples, the products of five commercial feather processors. Three samples were fermented prior to processing. Results of the experiment (Table 2) show that feather meal 6 produced a significant growth depression (p<.05) whereas the other feather meals gave results comparable to those obtained when chicks were fed the basal ration. The results show that commercial processing methods produce significant varia-
1237
tions in nutritive properties of feather meal. Since no detailed information on processing of the feathers is available, it is not known whether feather cooking conditions or lack of fermentation in the feathers prior to processing is responsible for poorer performance of feather meal 6 in relation to the other samples. Nitrogen retention data from chicks fed rations containing the seven samples (Table 2) show that dietary protein utilization was good and was not a limiting factor, which would explain the poor growth performance attributable to the one commercial sample. In vitro pepsin digestibility of feather meal samples did not appear to be related to chick growth when fed to furnish 5 percent protein. When a poultry by-product meal that recombines blood, offal and feathers in their naturally occurring proportions was fed to supply 5 percent protein to basal ration 1, growth was significantly improved (Table 2). This poultry byproduct, made by mixing separately processed components, shows that blood and offal improve the nutritive value of feathers, the combination being superior to feather meal. A combination of fish meal and dried whey failed to produce significant growth stimulation. Because previous work on amino acid deficiencies of feather protein was conducted with ground untreated feathers, experiments were undertaken to determine the amino acid deficiencies of processed (steam cooked) feather meals. It appeared possible that wet cooking of feathers under pressure could improve availability of some amino acids or destroy others, particularly those labile to heat. A preliminary trial was conducted to study the effect of amino acid supplementation on growth of chicks fed rations composed largely of corn and a single high
1238
E. C. N A B E R , S. P. T O U C H B U R N , B. D. B A R N E T T AND C. L. M O R G A N
TABLE 3.—Ejfecl of amino acid supplements on growth of chicks fed rations composed largely of soybean oil meal and/or feather meal and corn. Experiment 3 lai rations Ground yellow corn
Soybean oil meal
(%)
(%)
(%)
60.0 60.0
36.0 36.0
—
70.0 70.0 70.0
18.0 18.0 18.0
8.0 8.0 8.0
0.20 0.20
0.25 0.25
16.0 16.0 16.0
0.25 0.25
0.65 0.65
80.0 80.0 80.0 1 2
Feather meal
Ave. wt.2 at 4 wks. of age (grams)
Feed con v. to 4 wks. of age (gms. feed/ gms. gain)
395 409
1.77 1.72
0.05
305 398 377
1.86 1.77 1.65
0.10
74 176 256
2.47 1.83 1.89
Amino acid (%) DL-
L-
DL-
methionine
lysine
tryptophan
—
—
0.10
Ration for first group of chicks equals Basal Ration 1. Ten chicks per treatment.
protein feedstuff. Results indicated t h a t the corn-feather meal ration without amino acid supplements maintained the chicks b u t allowed little growth. Lysine (0.7 percent) greatly improved growth rate and a combination of 0.7 percent lysine and 0.4 percent methionine resulted in further growth improvement. When tryptophan and histidine (0.1 percent each) were added with the lysinemethionine combination, growth was further improved. However, growth on the corn-feather meal diet supplemented with all four amino acids was substantially lower than that obtained with the corn-soybean oil meal basal. When a corn-poultry by-product meal (recombined from processed feathers, offal and blood in naturally occurring proportions) ration was fed, chick growth was good. Growth on this diet was improved by 0.7 percent lysine and reached a maximum for the experiment when methionine, lysine, tryptophan and histidine were used in the same amounts as in the corn-feather meal diet above. Since about 60 percent of the protein in the combined poultry by-product meal originated from feathers, it is obvious
t h a t blood and offal contribute amino acids and possibly other factors t h a t permit maximum growth. The quantity of amino acid supplements t h a t improved performance on the corn-feather meal diet had only small effects when added to the corn-soybean basal or a corn-fish meal diet. Experiment 3 was conducted to compare growth on the corn-soybean diet with t h a t on the corn-feather meal diet and a diet in which corn, soybean oil meal and feather meal each contributed one-third of the protein. The results (Table 3) show t h a t excellent growth was obtained when the corn-soybean oil meal-feather meal diet was supplemented with methionine and lysine. T r y p t o p h a n did not improve growth on this diet in which feather meal provided one-third of the protein. Since practical poultry rations would seldom contain as much as one-third feather protein, methionine and lysine appear to be the only amino acids requiring attention in the formulation of rations containing similar quantities of corn and soybean protein. On the corn-feather meal diet, tryptophan improved growth rate over t h a t
FEATHER MEAL PROCESSING AND SUPPLEMENTATION
obtained from methionine and lysine supplementation. However, growth on the corn-feather meal diet, in which feathers provided two-thirds of the protein intake, did not approach that exhibited by chicks fed the basal diet in spite of supplementation with the three amino acids. Because it was possible to obtain essentially maximum growth rates with the corn-soybean oil meal-feather diet supplemented with methionine and lysine, this diet was used in experiment 4 in an attempt to evaluate seven samples of laboratory processed feather meal. Results shown in Table 4 reveal that it was possible to distinguish between a meal made from untreated feathers and six meals made from feathers treated under a variety of steam pressures for varying lengths of time. The untreated meal which depressed growth contained 16 percent pepsin digestible protein. The treated meals, all of which allowed normal growth, contained 64 to 83 percent pepsin digestible protein. Although there appeared to be a slight decrease in body weights associated with increases in steam pressure treatment, no treated meal produced results significantly different from the basal diet. Since the laboratory feather meals were prepared from clean washed feathers, it was thought desirable to compare several laboratory meals to commercial samples previously shown to be satisfactory substitutes for one-fourth of the protein in basal ration 1. Unprocessed laboratory meal retarded growth when fed to provide one-third of the protein intake in basal ration 1 (experiment 5, Table 4). When the laboratory processed meal (12.5 p.s.i. for 960 minutes) or the commercial meals were fed, growth was not statistically different from that shown by chicks fed the control ration. Because it was impossible to differen-
1239
tiate between the laboratory processed feather meals in the corn-soybean oil meal-feather meal diet, attempts were made to study the amino acid supplementation pattern of a simplified cornfeather meal diet with the hope that this diet properly supplemented with amino acids might be a better assay diet in which to evaluate laboratory processed feather meal samples. Accordingly, basal ration 2, which contained 20 percent protein and extensive vitamin supplementation, was modified to produce a corn-feather meal diet in which 60 percent of the total protein was furnished by feathers. It should be emphasized that the feather meal studied was a clean unfermented laboratory processed sample which had been steam cooked at 12.5 p.s.i. for 960 minutes. As expected from previous work, lysine and methionine supplementation proved to be essential for moderate growth (Table 5). Tryptophan and histidine were the third and fourth limiting amino acids. With all five amino acids present, growth was improved to the point where body weights were 70 percent of those obtained on the cornsoybean control diet. Thus, maximum growth on the corn-feather meal diet was not obtained with amino acid supplements even though calculations showed these to be the only limiting amino acids. In spite of failure to establish maximum growth by amino acid supplementation of simplified corn-feather meal diets, this diet was utilized in an attempt to evaluate the laboratory feather meal samples for possible processing effects in Experiment 7. Supplements of methionine, lysine and tryptophan were used to provide moderate growth. When experimentally processed pure feathers were fed as components of this diet (Table 4), it was possible to distinguish between meal made from untreated feathers and six treated meals.
83
960
30
90
240
20
7
—
—
12.5
30.0
30.0
30.0
60.0
90.0
—
—
—
—
74
72
64
70
338"
339"
347"
348"
366"
370"
285 '
1
379"'
1.63
380"
1.66
1.84
1.67
1.68
1.64
1.57
1.62
1.64
1.54
1.63
1.88
1.64
362"
358"
280
b
387"' 3.34
b
2.35 2.55 2.48 2.37 2.45
d
d
225' 1 222 d 236 d
213
45
59
56
55
56
57
2.48
248<> 252
33
46
50
3.04
145°
105
2.17
372"'
274°
269°
165°
171°
161°
162°
131
d
170°
55 b
436"7
1.76
1.76
2.03
1.92
2.05
2.04
2.06
2.15
2.88
1.59
Basal ration 1 plus 0.1% DL-methionine in Expt. 4 and 5. Basal ration 2 plus 0.2% m.-methionine in Expt. 7. Basal ration 3 plus 0.3% DL-methionine and 0.3% glycine in Expt. 13. 2 Cellulose substituted for feather meal in experimental diet. 3 Experimental diets supplemented with: 0.20% DL-methionine and 0.25% L-lysine in Expts. 4 and 5. 0.20% DL-methionine, 0.55% L-lysine and 0.20% DL-tryptophan in Expt. 7. 0.33% DL-methionine, 0.74% L-lysine, 0.07% DL-tryptophan and 0.20% L-histidine in Expt. 13. 1 Duplicate groups of 20 chicks each per treatment Expt. 4. Duplicate groups of 18 chicks each per treatment in Expt. 5. 5 Duplicate groups of 12 chicks each per treatment in Expt. 7. 6 Twenty chicks per treatment in Expt. 13. 7 Treatment averages that are significantly different (P<.05) from each other bear different superscript letters.
1
71
0
0
16
—
— _
—
Experiment No., basal ration and prot ein source in test diets Processing conditions Pepsin of feather meal digestiExpt. 75—Basal ration 2— Expt. 136—Basal sample used in the Expt. 4 and 54—Basal ration 1— (equal bility ration 3—(All protein (40% of protein from corn and experimental rations parts of protein furnished by corn, soybean of 60% of protein from feathers from feathers in the oil meal and feathers in the test diet) feather in test diet) test diet) meal Steam sample Ave. wt.. at 4 wks. Grams Grams feed per Av. wt. Grams Nitrogen Av. wt. pressure , Time (perat at retengram gam feed feed (gr ams) l linutes) (p.s.i.) cent) 4 wks. 4 wks. tion gain Expt. 4 Expt. 5 gain Expt. i> Expt. 4 (grams) (grams) (%)
of feather meal processing conditions on dietary utilization of protein as measured by growth, feed conversion and nitrogen retention of chicks
Control Ration Soybean Oil Meal 1 Experimental Rations 3 None2 Laboratory Feather Meal Laboratory Feather Meal Laboratory Feather Meal Laboratory Feather Meal Laboratory Feather Meal Laboratory Feather Meal Laboratory Feather Meal Commercial Feather Meal 1 Commercial Feather Meal 2
Experimental protein source in diet
TABLE 4.—Effect
1241
FEATHER MEAL PROCESSING AND SUPPLEMENTATION TABLE 5.—Effect
of amino acid supplementation on growth of chicks fed rations composed largely of feather meal and corn. Experiment 6
Variable components of experimental ration 1 SoyGround bean yellow oil corn meal
(%)
66.0 84.0 84.0 84.0 84.0 84.0 84.0 84.0 84.0 84.0
Amino acid supplement (%)
Feather meal (Laboratory processed at 12.5 p.s.i. for 960 min.)
methionine
L-
L-
lysine
arginine
tryptophane
30.0
—
0.1
— — — — — — — — —
12.0 12.0 12.0 12.0 12.0 12.0 12.0 12.0 12.0
—
— —
— — —
— — — —
(%)
DL-
0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2
0.55 0.55 0.55 0.55 0.55 0.55 0.55 0.55
0.1
DL-
— —
0.2
0.1 0.1
0.2
—
0.2 0.2
0.1
L-
histidine
— — — — —
—
0.1
—
0.1 0.1 0.1
—
Ave. body wt. at 4 wks.2 (grams)
Feed conv. at 4 wks. (grams feed/gram gain)
405"3 69b 190" 193° 245d 189° 246d 180° 271" 283*
1.77 2.99 2.04 2.10 2.09 2.08 2.06 2.08 2.02 1.92
1
Ration for first treatment equal Basal Ration 2. Duplicate groups of 8 chicks each per treatment. Treatment averages that are significantly different (P < .05) from each other bear different superscript letters. 2 3
However, it was not possible to distinguish between any treated meals. It is interesting to note that untreated feather meal was utilized to a small degree. When cellulose was substituted for feather meal in one experimental diet, chicks weighed 105 grams at 4 weeks of age whereas groups fed untreated feather meal averaged 145 grams. This difference was significant (p<.05). Thus, the chick used a small amount of protein from raw feathers (16 percent pepsin digestible). Nitrogen retention data show that less nitrogen was retained by chicks from the diet containing untreated feather meal than was retained from diets containing the six treated samples. Therefore, with six-tenths of the dietary protein from feathers, it was possible to distinguish between raw ground feather meal and treated feather meals but not among the treated samples using both growth and nitrogen retention as criteria. A final series of experiments was conducted to evaluate feather meal as the sole source of dietary protein. For this
purpose, basal ration 3 was employedAddition of methionine, lysine, histidine and tryptophan to a diet containing 12 percent protein from a commercial feather meal in quantities calculated to meet 12/20 of the NRC requirement permitted only a low level of growth (Table 6). Growth rate of birds receiving 12 percent protein from soybean oil meal was much more rapid than any of the groups receiving feather meal. In that feather meal is unusually high in cystine content, it was postulated that this might be responsible for poor performance of birds consuming diets high in feather meal. The addition of 0.4 percent Lcystine (the level calculated to make the diets equivalent in cystine to the soybean diet) did not indicate an antagonism. Increasing the dietary level of added lysine above 0.33 percent did not improve growth. Raising the tryptophan level above the NRC requirement did not affect growth and addition of 0.4 percent DL-phenylalanine had no beneficial effect. Increasing supplementary histidine from
1242
E. C. N A B E R , S. P . T O U C H B U R N , B. D. B A R N E T T AND C. L.
TABLE 6.—Effect
MORGAN
of amino acid supplementation on growth of chicks fed semipurified diets containing 12 percent protein from feather meal or soybean oil meal Amino acid supplement to basal ration 3 (%)
r roiein source in basal ration 3
DL-
methionine
L-
DL-
lysine
histidine
tryptophan
0.33 0.43 0.50 0.33 0.33 0.33 0.33
0.04 0.04 0.04 0.06 0.04 0.04 0.04
0.04 0.04 0.04 0.04 0.06 0.04 0.04
L-
DL-
Average body
L
phenylGlycine i . ^ alanine L
.,„t;„ cystin J
L-
weiguLs (grams)
arginme4weeks6weeks
1
Experiment 8 Feather Meal 0.20 Feather Meal 0.20 Feather Meal 0.20 Feather Meal 0.20 Feather Meal 0.20 Feather Meal 0.20 Feather Meal 0.20 Soybean Oil Meal 0.10 Soybean Oil Meal 0.10 Experiment 92 Feather Meal Feather Meal 1 2
0.20 0.20
0.40 0.30 0.40
0.33 0.33
0.06 0.06
0.04 0.04
0.10
69 66 73 77 75 74 74 290 303
115 98 104 156 114 117 117
100 84
— —
— —
Ten chicks per treatment. Fifteen chicks per treatment
the theoretical requirement of 0.04 to 0.06 percent, however, markedly increased six week weight. T h e addition of 0.1 percent arginine to the 12 percent protein diet did not further improve the diet. Due to a high incidence of cannibalism on the 12 percent protein diets, similar experiments were conducted with 20 percent protein diets. With these diets, as with the low protein diets, there was little or no response from levels of methionine, lysine, tryptophan, phenylalanine or arginine above the N R C requirement (Table 7-experiment 10). Increasing added histidine to 0.15 percent elicited a marked growth response. There was little response from the addition of higher levels of methionine, lysine, tryptophan, phenylalanine and arginine to the diet containing 0.15 percent added histidine. Experiments 11 and 12 (Table 7) were conducted to determine the level of supplementary histidine required for maximum chick growth on a semi-purified diet containing 20 percent protein from a commercial feather meal. These trials
indicated t h a t 0.2 percent was probably adequate although there was a tendency for increased weight u p to 0.25 percent. In that growth on all feather meal diets was markedly inferior to growth on soybean oil meal diets, it seemed advisable to study the effect of method of processing on the nutritive value of feather meal when used as the sole source of protein. Methionine, lysine, t r y p t o p h a n and histidine supplements were used in all feather meal diets. The results of Experiment 13 show t h a t finely ground raw feathers promoted a very low rate of growth (Table 4). Chicks fed the diets containing the six processed samples grew a t a moderate rate. However, the group of chicks fed feather meal processed for 30 minutes under 30 p.s.i. showed a significantly lower growth rate ( p < . 0 5 ) t h a n those fed other experimentally processed samples. Thus, the sample processed for a period of 30 minutes under 30 p.s.i. (pepsin digestibility of 64 percent) appeared to be inferior to other treated samples (pepsin digestibilities of 70 to 83 percent). The d a t a suggest t h a t
1243
FEATHER MEAL PROCESSING AND SUPPLEMENTATION
there is some relationship of pepsin digestibility to the chicks utilization of feather protein. Commercial feather meals fed as the sole source of protein produced better growth than any of the laboratory processed meals. This finding emphasizes the importance of contamination by nonfeather substances and/or fermentation to the growth promoting properties of feather meal. Experiments conducted with basal ration 3 indicate that chick growth was poor when all the protein was supplied by a commercial feather meal in both 12 percent protein and 20 percent protein diets even though amino acids were supplied in quantities to meet the requirement given by the National Research Council (NRC). Growth rate was improved when the level of histidine was increased beyond the level needed to meet the NRC requirement. This indicated that either the histidine of feather meal TABLE 7.—Effect
was unavailable or the requirement is higher than 0.15 percent. Almquist (1956) and Rosenberg et al. (1957) reported the histidine requirement of the chick to be 0.3 percent of the diet. Supplementary histidine required to promote maximum growth in these trials plus that contained in the meal as reported by Gregory et al. (1956) approximates 0.3 percent. Failure to obtain maximum growth with amino acid supplementation indicates that some factor other than amino acid composition is responsible for poor results obtained with diets high in feather meal. Although assays indicate the presence of adequate amounts of glycine, leucine, isoleucine, threonine and valine in feather meal, it may be that one or more of these amino acids are limiting due to inability of the chick to digest and assimilate them from feather meal protein. Another possible reason for failure to
of amino acid supplementation on growth of chicks fed semipurified diets containing 20 percent protein from feather meal or soybean oil meal f Average body weights at 4 weeks (grams)
Amino acid supplement to basal ration 3 (%) Protein source in basal ration 3
Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Soybean Oil Meal 1
L-
Dt-
methio- L-lysine nine 0.33 0.46 0.33 0.33 0.33 0.33 0.33 0.46 0.46 0.46 0.46 0.33 0.33 0.33 0.33 0.33 0.33 0.30
0.74 0.74 1.18 0.74 0.74 0.74 0.74 1.18 1.18 1.18 1.18 0.74 0.74 0.74 0.74 0.74 0.74
histidine 0.06 0.06 0.06 0.15 0.06 0.06 0.06 0.06 0.06 0.15 0.15 0.10 0.175 0.20 0.225 0.25 0.30
DL
0.07 0.07 0.07 0.07 0.21 0.07 0.07 0.07 0.21 0.21 0.21 0.07 0.07 0.07 0.07 0.07 0.07
L-
. .
^
m D e
Glycine Expt. 101 104 113 112 196 99 100 112 112 113 220 212
0.42 0.30
0.42
Eighteen chicks per treatment. Twenty chicks per treatment. 3 Duplicate groups of sixteen chicks each per treatment.
2
"
tryptophenylphan alanine
0.30
Expt. II 2
Expt. 123
96 193
213
158 250
0.30
428
239 361
244 248 255 262 430
1244
E. C. NABER, S. P. TOUCHBURN, B. D. BARNETT AND C. L. MORGAN
obtain maximum growth on diets heavily dependent on feather protein might be the presence of toxic principles in feather meal. While this possibility cannot be overlooked, it appears unlikely because it was possible to obtain maximum growth with diets containing one-third of their protein from feather meal. It appears, therefore, that the most likely explanation for failure to obtain maximum growth on diets high in feather protein is poor amino acid availability. Further work is needed to clarify this point. SUMMARY
Properly processed feather meal was used to supply up to one-quarter of the crude protein in chick starting rations containing large amounts of protein from soybean oil meal and corn. Under these conditions, chick growth was excellent and dietary nitrogen utilization was not impaired. Contamination of feathers with offal and blood and/or fermentation of the feathers were found to be important factors influencing growth on feather meal diets. When feather meal was used to supply one-third or more of the total dietary protein, amino acid deficiency problems were encountered. In experimental diets where corn, soybean oil meal, and feather meal each contributed one-third of the crude protein, lysine and methionine supplementation were required to restore maximum growth rate. When one-half or more of the protein was contributed by feather meal, the amino acid deficiencies extended to tryptophan, histidine and perhaps other amino acids. Experimental processing of feathers for meal production showed that the method employed does affect the nutritive value of the product. One sample of feather meal containing 64 percent pepsin digestible protein was inferior to other samples
containing 70 to 83 percent pepsin digestible protein when fed to chicks as the sole source of protein. ACKNOWLEDGMENTS
The authors are grateful to the Byproduct Division of J. D. Jewell, Inc., Gainesville, Georgia and the SmithRowland Company, Norfolk, Virginia, for supplies of commercial feather meal. We wish to thank Dr. J. G. Davis, Poultry Laboratory, Western Utilization Research and Development Division, U. S. Department of Agriculture, Albany, California, for supplying the series of commercial and laboratory processed feather meal samples used in this work. Data on pepsin digestibility, nitrogen content and amino acid composition of the feather meals was also furnished by Dr. Davis. REFERENCES Almquist, H. J., 1956. Amino Acid Handbook by R. J. Block and K. W. Weiss, p. 164. Charles C Thomas, Springfield, Illinois. Binkley, C. H., and O. R. Vasak, 1950. Production of a friable meal from feathers. Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, U.S.D.A. Publication No. AIC-274. Bird, H. R., H. J. Almquist, W. W. Cravens, F. W. Hill and J. McGinnis, 1954. Nutrient requirements for poultry. Publication 301, National Research Council, Washington, D. C. Block, R. J., and D. Boiling, 1951. The Amino Acid Composition of Proteins and Foods. Charles C Thomas, Springfield, Illinois, Second Ed. Davis, J. G., 1958. Personal communication. Elmslie, W. P., 1958. A report on digestibility of proteins. J. Assoc. Off. Agr. Chem. 41: 233-240. Gerht, A. J., M. J. Caldwell and W. P. Elmslie, 1955. Chemical method for measuring relative digestibility of animal protein feedstuffs. J. Agr. Food. Chem. 3: 159-162. Gregory, B. R., O. H. M. Wilder and P. C. Ostby, 1956. Studies on the amino acid and vitamin composition of feather meal. Poultry Sci. 35: 234-235. Lillie, R. J., J. R. Sizemore and C. A. Denton, 1956. Feather meal in chick nutrition. Poultry Sci. 35:316-318.
FEATHER MEAL PROCESSING AND SUPPLEMENTATION Mangold, E., and J. Dubski, 1930. The digestion of keratin, especially the horny material of birds' feathers, by fowls and mammals. Wiss. Arch. Landw., Abt. B, Tierernahr. Tierzucht 4: 200221. McKerns, K. W., and E. Rittersporn, 1958. The nutritional significance of processed keratin in poultry feeding. Poultry Sci. 37: 433-436. Naber, E. C , and C. L. Morgan, 1956. Feather meal and poultry meat scrap in chick starting rations. Poultry Sci. 35: 888-895. Rosenberg, H. R., J. T. Baldini and C. I. Tollefson, 1957. Histidine requirement of the growing chick.
1245
Poultry Sci. 36: 1381-1382. Routh, J. I., 1942. Nutritional studies on powdered chicken feathers. J. Nutr. 24: 399-404. Sullivan, T. W., and E. L. Stephenson, 1957. Effect of processing methods on the utilization of hydrolyzed poultry feathers by growing chicks. Poultry Sci. 36: 361-365. Wilder, O. H. M., P. C. Ostby and B. R. Gregory, 1955. The use of chicken feather meal in feeds. Poultry Sci. 34: 518-524. Wisman, E. L., C. E. Holmes and R. W. Engel, 1958. Utilization of poultry by-products in poultry rations. Poultry Sci. 37: 834-838.
Reinvestigation of the Vitamin A Requirements of Laying and Breeding Hens and Their Progeny F. W. HILL, 1 M. L. SCOTT, L. C. NORRIS AND G. F. HETJSER2 Department of Poultry Husbandry, Cornell University, Ithaca, N. Y. (Received for publication November 4, 1960)
O
N THE basis of the available evidence from quantitative studies, the Committee on Animal Nutrition of the National Research Council (1954) has estimated the vitamin A requirements to be 1,200 U.S.P. units per pound of diet for growing chickens, and 2,000 U.S.P. units per pound of diet for laying and breeding hens. The results of individual studies on which these estimates are based have varied widely. The sources of vitamin A activity used in the various studies on requirement were fish oils, alfalfa meals and/or yellow corn, all of which were unstable to some degree, especially after mixture in the experimental diets. Even with the precaution of frequent diet mixing, the instability of the vitamin or its precursors introduced considerable uncertainty into the quantitative estimates of requirement.
1 Present address: Department of Poultry Husbandry, University of California, Davis, California. 2 Present address: 608 Hillside Drive, Lakeland, Florida.
Recently, efforts in industry have been directed toward the development of vitamin A preparations which are highly stable in diet mixtures and under adverse conditions of storage. Reinvestigation of the vitamin A requirements of hens and their progeny using one of these "stabilized" vitamin A preparations was considered appropriate because of the uncertainties concerned in earlier work and the wide variations in estimates derived from the different experiments. One of the abnormalities associated with vitamin A deficiency in hens is the production of eggs with a high incidence of blood spotting of the yolk (Bearse et al., 1960). This egg defect normally occurs in low incidence among commercial strains of chickens, but is known to be an inherited trait (Lerner et al., 1951). The studies to be described were undertaken to investigate the requirement of hens and their progeny for vitamin A, using a stabilized source of vitamin A and strains of chickens differing widely in their
TOUCHBURN
Department of Poultry Science, Ohio State University, Columbus 10, Ohio AND B . D . B A R N E T T A N D C. L .
MORGAN
Department of Poultry Husbandry, South Carolina Agricultural Experiment Station, Clemson, South Carolina (Received for publication November 3, 1960)
INTRODUCTION
T
HE keratin proteins have generally been considered to be of little nutritive value because of their chemical structure which makes them insoluble and poorly digestible. Early attempts to use powdered sources of keratin as dietary protein were only slightly successful even when amino acid supplements were provided to offset the deficiencies of these proteins. Routh (1942) reported that powdered chicken feathers, as the sole source of protein for rats, were capable of supporting a moderate growth rate only when supplemented by tryptophan, methionine, histidine and lysine. Balance experiments conducted by Mangold and Dubski (1930) failed to show any digestion of white goose feathers by cats and owls. Thus it appeared that native feather keratin was not only seriously deficient in certain amino acids but was also poorly digestible. The development by Binkley and Vasak (1950) of a method for processing feathers into a friable, high density meal stimulated new investigation of the nutritive value of feather keratin.
It is apparent from the experimental findings of Wilder et al. (1955), Lillie et al. (1956), Naber and Morgan (1956), Wisman et al. (1958) and McKerns and Rittersporn (1958) that commercial feather meal, processed by the steam cooking method, can be utilized by the chick as a source of dietary protein, certain vitamins and unidentified growth factors. The degree to which feather meal protein can be utilized by the chick still remains in doubt. In addition, no evidence that processing conditions alter utilization of protein from feather meal was found by Sullivan and Stephenson (1957). Since feathers from poultry slaughter plants often undergo fermentation prior to processing and are contaminated with blood and offal, it is difficult to determine the true nutritive properties of processed feather protein. Finally, the amino acid deficiences of steam cooked feather meal have not been studied extensively. The experiments reported here deal with the effect of feather processing conditions or methods and amino acid supplementation of feather meal on chick growth, feed utilization and nitrogen retention.
1
Published with approval of the Directors of the Ohio Agricultural Experiment Station and the South Carolina Agricultural Experiment Station. Presented in part at the Annual Meeting of the American Institute of Nutrition in April, 1959 at Atlantic City, New Jersey.
EXPERIMENTAL
Day-old meat-type chicks were wingbanded for identification, vaccinated intranasally for Newcastle disease and
1234
1235
FEATHER MEAL PROCESSING AND SUPPLEMENTATION TABLE 1.—Basal rations i
I in experiments Ration No.
Major ingredients (grams per kilogram) Ground yellow corn Sucrose Refined corn oil Soybean oil meal (44% protein) Soybean oil meal (50% protein) Defluorinated rock phosphate (31% calcium and 18% phosphorus) Ground limestone (38% calcium) Iodized salt (0.007% iodine) Manganese sulfate (27% manganese) Salts mixture* Choline Chloride • Minor ingredients (units per kilogram) Vitamin A, U.S.P. units Vitamin Da, I.C. units DL alpha tocopherol acetate, mgs. 2 methyl 1,4-naphthoquinone, mgs. Thiamine, mgs. Riboflavin, mgs. Calcium pantothenate, mgs. Niacin, mgs. Pyridoxine, mgs. Folacin, mgs. Biotin, mgs. Cyanocabalamin, megs. Para amino benzoic acid, mgs. Procaine penicillin, mgs. Chlorotetracycline, gms. Percent crude protein content Composition of salts mixture CaCOs K2HPO4 CaHPCv2H 2 0 NaCI MgS0 4 -7H 2 0 Fe Citrate-6H 2 0 MnSCvH20 KI CuS0 4 -5H 2 0 ZnCl 2
600
660
— —
498 55
360
— —
300
—
—
385
20 IS 5 0.22
20 IS 5 0.44
—
—
— — —
1.1
,200 600
—
1.1
—
4.4 11.0 44.0
— — —
9.9
— —
10.0 21.2
1.1
8,800 1,320 8 1.1 2.2 7.7 15.4 44.0 4.4 4.4 0.22 26.4
— —
10.0 20.0
—
60 2.0
10,000 2,000 10 0.5 10.0 6.0 20.0 50.0 4.0 4.0 0.22 20.0 100.0 10.0
—
20.0
3,803.2 2,580.0 1,190.0 1,340.0 816.0 220.0 40.0 6.4 2.4 2.0 10,000.0 parts
infectious bronchitis and reared in electrically heated batteries with raised wire floors. Ten to 20 chicks were used in each experimental group with the sexes equally represented. Feed and water were supplied ad libitum. When experiments were conducted beyond four or five weeks of age, birds were transferred to standard growing batteries. Records of body weight, feed consumption and mortality were maintained.
In most experiments, body weight data were subjected to the analysis of variance. When statistically significant differences between treatment means were found by application of the F test, Duncan's multiple range test was used to determine the significance of differences among the experimental treatments. In the tables, treatment averages which differ significantly (p<.05) have superscripts of different letters. Treatment
1236
E. C. N A B E E , S. P. TOUCHBTJRN, B. D. B A R N E T T AND C. L.
MORGAN
TABLE 2.—A comparison of commercially processed feather meeds on growth, feed conversion and nitrogen retention of chicks. Experiment 1 Data on feather meal sampl es Supplement to basal Ration 1 plus 0.05% DLmethionine1 None Feather Meal 5 Feather Meal 6 Feather Meal 7 Feather Meal 8 Feather Meal 9 Feather Meal 10 Feather Meal 11 Poultry By Product Meal2 2 % Fish Meal and 2% whey 1
% pepsin digestibility of meal
Av. body wt.3 at 8 wks (grams)
Feed .% conversion nitrogen4 (grams feed retained per gm. gain)
Manufacturer
Fermentation step prior to processing
—
—
—
A B B C C D E
No No Yes No Yes No Yes
51 59 82 57 59 65 60
13.4 13.5 14.2 13.8 13.0 13.9 14.0
1,174*5 1,123" l,096 b 1,136" 1,134" 1,155" 1,144" 1,157"
2.26 2.19 2.23 2.28 2.19 2.22 2.20 2.21
52.3 59.1 57.3 56.1 60.1 60.5 57.5 54.4
—
—
—
__
1,242°
2.27
52.7
—
—
—
—
1,194"
2.28
53.8
%
nitrogen in meal
Feather meals and poultry by-products meal used in quantities to furnish 5% protein in experimenta1
diet. 2
Composed of feathers, blood and offal in naturally occurring proportions. Duplicate groups of 20 chicks each per treatment. During a four day test period after the chicks were three weeks of age. £ Treatment averages that are significantly different ( P < .05) from each other bear different superscript letters. 3
4
averages bearing the same superscript letter are not significantly different (p>.05). In some experiments, nitrogen retention was measured. Retention was calculated from the difference between total nitrogen intake and total nitrogen excretion. Feces were collected by placing trays containing one normal sulfuric acid under the wire floors of a metabolism cage for a 96 hour period. Fecal markers (Sudan Red I I I in gelatin capsules) were employed to indicate the beginning and end of each collection period. Fecal homogenates and feed samples were analyzed for Kjeldahl nitrogen and calculations of retention were made. Composition of the basal experimental rations is shown in Table 1. Rations 1 and 2 are semi-practical corn-soybean oil meal rations. Ration 2 contains less crude protein and more vitamin fortification than does Ration 1. Ration 3 is a semipurified ration utilizing 50 percent protein soybean oil meal as the sole protein
source. Feather meal and other protein feedstuffs were isonitrogenously substituted in these basal rations with adjustments in the soybean oil meal and corn or sucrose levels. In several experiments, the protein level of Ration 3 was reduced to 12 percent by adjusting the ratio of sucrose to soybean oil meal or feather meal. Amino acid supplementation levels used in these experiments were based on calculated deficiencies in the rations. Calculations were made from data on amino acid composition of feather meal published by Gregory et al. (1956) and Davis (1958). Summary data on amino acid composition published by Block and Boiling (1951) was used for other protein feedstuffs. Based on requirements for amino acids published by the National Research Council (Bird et al., 1954), it appeared t h a t feather meal supplied less than the required amounts of lysine, histidine, methionine, tryptophan and possibly phenylalanine. In addition, the
FEATHER MEAL PROCESSING AND SUPPLEMENTATION
amount of arginine supplied by feather meal was very near the stated requirement. A series of commercial and laboratory processed feather meal samples was tested during the course of this work. Seven commercially processed samples including three samples that had been fermented prior to processing were employed. Laboratory processed meals were prepared from clean unfermented feathers. Processing consisted of steam pressure cooking of feathers under several conditions of pressure and time. Untreated raw feathers were used as controls. All samples were dried at 140°F. and ground to produce a free flowing meal. In vitro pepsin digestibility of feather meal samples was determined by the method described by Gehrt et al. (1955) as modified by Elmslie (1958). RESULTS AND DISCUSSION
Preliminary work showed that four samples of commercial feather meal previously tested by Naber and Morgan (1956) were capable of supplying onequarter of the protein in chick starting rations. Since these samples represented only two commercial sources of the product, it appeared desirable to compare a variety of feather meal sources to determine whether or not commercial sources vary in their ability to replace 5 percent of protein in basal ration 1. Thus an experiment was conducted to test seven feather meal samples, the products of five commercial feather processors. Three samples were fermented prior to processing. Results of the experiment (Table 2) show that feather meal 6 produced a significant growth depression (p<.05) whereas the other feather meals gave results comparable to those obtained when chicks were fed the basal ration. The results show that commercial processing methods produce significant varia-
1237
tions in nutritive properties of feather meal. Since no detailed information on processing of the feathers is available, it is not known whether feather cooking conditions or lack of fermentation in the feathers prior to processing is responsible for poorer performance of feather meal 6 in relation to the other samples. Nitrogen retention data from chicks fed rations containing the seven samples (Table 2) show that dietary protein utilization was good and was not a limiting factor, which would explain the poor growth performance attributable to the one commercial sample. In vitro pepsin digestibility of feather meal samples did not appear to be related to chick growth when fed to furnish 5 percent protein. When a poultry by-product meal that recombines blood, offal and feathers in their naturally occurring proportions was fed to supply 5 percent protein to basal ration 1, growth was significantly improved (Table 2). This poultry byproduct, made by mixing separately processed components, shows that blood and offal improve the nutritive value of feathers, the combination being superior to feather meal. A combination of fish meal and dried whey failed to produce significant growth stimulation. Because previous work on amino acid deficiencies of feather protein was conducted with ground untreated feathers, experiments were undertaken to determine the amino acid deficiencies of processed (steam cooked) feather meals. It appeared possible that wet cooking of feathers under pressure could improve availability of some amino acids or destroy others, particularly those labile to heat. A preliminary trial was conducted to study the effect of amino acid supplementation on growth of chicks fed rations composed largely of corn and a single high
1238
E. C. N A B E R , S. P. T O U C H B U R N , B. D. B A R N E T T AND C. L. M O R G A N
TABLE 3.—Ejfecl of amino acid supplements on growth of chicks fed rations composed largely of soybean oil meal and/or feather meal and corn. Experiment 3 lai rations Ground yellow corn
Soybean oil meal
(%)
(%)
(%)
60.0 60.0
36.0 36.0
—
70.0 70.0 70.0
18.0 18.0 18.0
8.0 8.0 8.0
0.20 0.20
0.25 0.25
16.0 16.0 16.0
0.25 0.25
0.65 0.65
80.0 80.0 80.0 1 2
Feather meal
Ave. wt.2 at 4 wks. of age (grams)
Feed con v. to 4 wks. of age (gms. feed/ gms. gain)
395 409
1.77 1.72
0.05
305 398 377
1.86 1.77 1.65
0.10
74 176 256
2.47 1.83 1.89
Amino acid (%) DL-
L-
DL-
methionine
lysine
tryptophan
—
—
0.10
Ration for first group of chicks equals Basal Ration 1. Ten chicks per treatment.
protein feedstuff. Results indicated t h a t the corn-feather meal ration without amino acid supplements maintained the chicks b u t allowed little growth. Lysine (0.7 percent) greatly improved growth rate and a combination of 0.7 percent lysine and 0.4 percent methionine resulted in further growth improvement. When tryptophan and histidine (0.1 percent each) were added with the lysinemethionine combination, growth was further improved. However, growth on the corn-feather meal diet supplemented with all four amino acids was substantially lower than that obtained with the corn-soybean oil meal basal. When a corn-poultry by-product meal (recombined from processed feathers, offal and blood in naturally occurring proportions) ration was fed, chick growth was good. Growth on this diet was improved by 0.7 percent lysine and reached a maximum for the experiment when methionine, lysine, tryptophan and histidine were used in the same amounts as in the corn-feather meal diet above. Since about 60 percent of the protein in the combined poultry by-product meal originated from feathers, it is obvious
t h a t blood and offal contribute amino acids and possibly other factors t h a t permit maximum growth. The quantity of amino acid supplements t h a t improved performance on the corn-feather meal diet had only small effects when added to the corn-soybean basal or a corn-fish meal diet. Experiment 3 was conducted to compare growth on the corn-soybean diet with t h a t on the corn-feather meal diet and a diet in which corn, soybean oil meal and feather meal each contributed one-third of the protein. The results (Table 3) show t h a t excellent growth was obtained when the corn-soybean oil meal-feather meal diet was supplemented with methionine and lysine. T r y p t o p h a n did not improve growth on this diet in which feather meal provided one-third of the protein. Since practical poultry rations would seldom contain as much as one-third feather protein, methionine and lysine appear to be the only amino acids requiring attention in the formulation of rations containing similar quantities of corn and soybean protein. On the corn-feather meal diet, tryptophan improved growth rate over t h a t
FEATHER MEAL PROCESSING AND SUPPLEMENTATION
obtained from methionine and lysine supplementation. However, growth on the corn-feather meal diet, in which feathers provided two-thirds of the protein intake, did not approach that exhibited by chicks fed the basal diet in spite of supplementation with the three amino acids. Because it was possible to obtain essentially maximum growth rates with the corn-soybean oil meal-feather diet supplemented with methionine and lysine, this diet was used in experiment 4 in an attempt to evaluate seven samples of laboratory processed feather meal. Results shown in Table 4 reveal that it was possible to distinguish between a meal made from untreated feathers and six meals made from feathers treated under a variety of steam pressures for varying lengths of time. The untreated meal which depressed growth contained 16 percent pepsin digestible protein. The treated meals, all of which allowed normal growth, contained 64 to 83 percent pepsin digestible protein. Although there appeared to be a slight decrease in body weights associated with increases in steam pressure treatment, no treated meal produced results significantly different from the basal diet. Since the laboratory feather meals were prepared from clean washed feathers, it was thought desirable to compare several laboratory meals to commercial samples previously shown to be satisfactory substitutes for one-fourth of the protein in basal ration 1. Unprocessed laboratory meal retarded growth when fed to provide one-third of the protein intake in basal ration 1 (experiment 5, Table 4). When the laboratory processed meal (12.5 p.s.i. for 960 minutes) or the commercial meals were fed, growth was not statistically different from that shown by chicks fed the control ration. Because it was impossible to differen-
1239
tiate between the laboratory processed feather meals in the corn-soybean oil meal-feather meal diet, attempts were made to study the amino acid supplementation pattern of a simplified cornfeather meal diet with the hope that this diet properly supplemented with amino acids might be a better assay diet in which to evaluate laboratory processed feather meal samples. Accordingly, basal ration 2, which contained 20 percent protein and extensive vitamin supplementation, was modified to produce a corn-feather meal diet in which 60 percent of the total protein was furnished by feathers. It should be emphasized that the feather meal studied was a clean unfermented laboratory processed sample which had been steam cooked at 12.5 p.s.i. for 960 minutes. As expected from previous work, lysine and methionine supplementation proved to be essential for moderate growth (Table 5). Tryptophan and histidine were the third and fourth limiting amino acids. With all five amino acids present, growth was improved to the point where body weights were 70 percent of those obtained on the cornsoybean control diet. Thus, maximum growth on the corn-feather meal diet was not obtained with amino acid supplements even though calculations showed these to be the only limiting amino acids. In spite of failure to establish maximum growth by amino acid supplementation of simplified corn-feather meal diets, this diet was utilized in an attempt to evaluate the laboratory feather meal samples for possible processing effects in Experiment 7. Supplements of methionine, lysine and tryptophan were used to provide moderate growth. When experimentally processed pure feathers were fed as components of this diet (Table 4), it was possible to distinguish between meal made from untreated feathers and six treated meals.
83
960
30
90
240
20
7
—
—
12.5
30.0
30.0
30.0
60.0
90.0
—
—
—
—
74
72
64
70
338"
339"
347"
348"
366"
370"
285 '
1
379"'
1.63
380"
1.66
1.84
1.67
1.68
1.64
1.57
1.62
1.64
1.54
1.63
1.88
1.64
362"
358"
280
b
387"' 3.34
b
2.35 2.55 2.48 2.37 2.45
d
d
225' 1 222 d 236 d
213
45
59
56
55
56
57
2.48
248<> 252
33
46
50
3.04
145°
105
2.17
372"'
274°
269°
165°
171°
161°
162°
131
d
170°
55 b
436"7
1.76
1.76
2.03
1.92
2.05
2.04
2.06
2.15
2.88
1.59
Basal ration 1 plus 0.1% DL-methionine in Expt. 4 and 5. Basal ration 2 plus 0.2% m.-methionine in Expt. 7. Basal ration 3 plus 0.3% DL-methionine and 0.3% glycine in Expt. 13. 2 Cellulose substituted for feather meal in experimental diet. 3 Experimental diets supplemented with: 0.20% DL-methionine and 0.25% L-lysine in Expts. 4 and 5. 0.20% DL-methionine, 0.55% L-lysine and 0.20% DL-tryptophan in Expt. 7. 0.33% DL-methionine, 0.74% L-lysine, 0.07% DL-tryptophan and 0.20% L-histidine in Expt. 13. 1 Duplicate groups of 20 chicks each per treatment Expt. 4. Duplicate groups of 18 chicks each per treatment in Expt. 5. 5 Duplicate groups of 12 chicks each per treatment in Expt. 7. 6 Twenty chicks per treatment in Expt. 13. 7 Treatment averages that are significantly different (P<.05) from each other bear different superscript letters.
1
71
0
0
16
—
— _
—
Experiment No., basal ration and prot ein source in test diets Processing conditions Pepsin of feather meal digestiExpt. 75—Basal ration 2— Expt. 136—Basal sample used in the Expt. 4 and 54—Basal ration 1— (equal bility ration 3—(All protein (40% of protein from corn and experimental rations parts of protein furnished by corn, soybean of 60% of protein from feathers from feathers in the oil meal and feathers in the test diet) feather in test diet) test diet) meal Steam sample Ave. wt.. at 4 wks. Grams Grams feed per Av. wt. Grams Nitrogen Av. wt. pressure , Time (perat at retengram gam feed feed (gr ams) l linutes) (p.s.i.) cent) 4 wks. 4 wks. tion gain Expt. 4 Expt. 5 gain Expt. i> Expt. 4 (grams) (grams) (%)
of feather meal processing conditions on dietary utilization of protein as measured by growth, feed conversion and nitrogen retention of chicks
Control Ration Soybean Oil Meal 1 Experimental Rations 3 None2 Laboratory Feather Meal Laboratory Feather Meal Laboratory Feather Meal Laboratory Feather Meal Laboratory Feather Meal Laboratory Feather Meal Laboratory Feather Meal Commercial Feather Meal 1 Commercial Feather Meal 2
Experimental protein source in diet
TABLE 4.—Effect
1241
FEATHER MEAL PROCESSING AND SUPPLEMENTATION TABLE 5.—Effect
of amino acid supplementation on growth of chicks fed rations composed largely of feather meal and corn. Experiment 6
Variable components of experimental ration 1 SoyGround bean yellow oil corn meal
(%)
66.0 84.0 84.0 84.0 84.0 84.0 84.0 84.0 84.0 84.0
Amino acid supplement (%)
Feather meal (Laboratory processed at 12.5 p.s.i. for 960 min.)
methionine
L-
L-
lysine
arginine
tryptophane
30.0
—
0.1
— — — — — — — — —
12.0 12.0 12.0 12.0 12.0 12.0 12.0 12.0 12.0
—
— —
— — —
— — — —
(%)
DL-
0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2
0.55 0.55 0.55 0.55 0.55 0.55 0.55 0.55
0.1
DL-
— —
0.2
0.1 0.1
0.2
—
0.2 0.2
0.1
L-
histidine
— — — — —
—
0.1
—
0.1 0.1 0.1
—
Ave. body wt. at 4 wks.2 (grams)
Feed conv. at 4 wks. (grams feed/gram gain)
405"3 69b 190" 193° 245d 189° 246d 180° 271" 283*
1.77 2.99 2.04 2.10 2.09 2.08 2.06 2.08 2.02 1.92
1
Ration for first treatment equal Basal Ration 2. Duplicate groups of 8 chicks each per treatment. Treatment averages that are significantly different (P < .05) from each other bear different superscript letters. 2 3
However, it was not possible to distinguish between any treated meals. It is interesting to note that untreated feather meal was utilized to a small degree. When cellulose was substituted for feather meal in one experimental diet, chicks weighed 105 grams at 4 weeks of age whereas groups fed untreated feather meal averaged 145 grams. This difference was significant (p<.05). Thus, the chick used a small amount of protein from raw feathers (16 percent pepsin digestible). Nitrogen retention data show that less nitrogen was retained by chicks from the diet containing untreated feather meal than was retained from diets containing the six treated samples. Therefore, with six-tenths of the dietary protein from feathers, it was possible to distinguish between raw ground feather meal and treated feather meals but not among the treated samples using both growth and nitrogen retention as criteria. A final series of experiments was conducted to evaluate feather meal as the sole source of dietary protein. For this
purpose, basal ration 3 was employedAddition of methionine, lysine, histidine and tryptophan to a diet containing 12 percent protein from a commercial feather meal in quantities calculated to meet 12/20 of the NRC requirement permitted only a low level of growth (Table 6). Growth rate of birds receiving 12 percent protein from soybean oil meal was much more rapid than any of the groups receiving feather meal. In that feather meal is unusually high in cystine content, it was postulated that this might be responsible for poor performance of birds consuming diets high in feather meal. The addition of 0.4 percent Lcystine (the level calculated to make the diets equivalent in cystine to the soybean diet) did not indicate an antagonism. Increasing the dietary level of added lysine above 0.33 percent did not improve growth. Raising the tryptophan level above the NRC requirement did not affect growth and addition of 0.4 percent DL-phenylalanine had no beneficial effect. Increasing supplementary histidine from
1242
E. C. N A B E R , S. P . T O U C H B U R N , B. D. B A R N E T T AND C. L.
TABLE 6.—Effect
MORGAN
of amino acid supplementation on growth of chicks fed semipurified diets containing 12 percent protein from feather meal or soybean oil meal Amino acid supplement to basal ration 3 (%)
r roiein source in basal ration 3
DL-
methionine
L-
DL-
lysine
histidine
tryptophan
0.33 0.43 0.50 0.33 0.33 0.33 0.33
0.04 0.04 0.04 0.06 0.04 0.04 0.04
0.04 0.04 0.04 0.04 0.06 0.04 0.04
L-
DL-
Average body
L
phenylGlycine i . ^ alanine L
.,„t;„ cystin J
L-
weiguLs (grams)
arginme4weeks6weeks
1
Experiment 8 Feather Meal 0.20 Feather Meal 0.20 Feather Meal 0.20 Feather Meal 0.20 Feather Meal 0.20 Feather Meal 0.20 Feather Meal 0.20 Soybean Oil Meal 0.10 Soybean Oil Meal 0.10 Experiment 92 Feather Meal Feather Meal 1 2
0.20 0.20
0.40 0.30 0.40
0.33 0.33
0.06 0.06
0.04 0.04
0.10
69 66 73 77 75 74 74 290 303
115 98 104 156 114 117 117
100 84
— —
— —
Ten chicks per treatment. Fifteen chicks per treatment
the theoretical requirement of 0.04 to 0.06 percent, however, markedly increased six week weight. T h e addition of 0.1 percent arginine to the 12 percent protein diet did not further improve the diet. Due to a high incidence of cannibalism on the 12 percent protein diets, similar experiments were conducted with 20 percent protein diets. With these diets, as with the low protein diets, there was little or no response from levels of methionine, lysine, tryptophan, phenylalanine or arginine above the N R C requirement (Table 7-experiment 10). Increasing added histidine to 0.15 percent elicited a marked growth response. There was little response from the addition of higher levels of methionine, lysine, tryptophan, phenylalanine and arginine to the diet containing 0.15 percent added histidine. Experiments 11 and 12 (Table 7) were conducted to determine the level of supplementary histidine required for maximum chick growth on a semi-purified diet containing 20 percent protein from a commercial feather meal. These trials
indicated t h a t 0.2 percent was probably adequate although there was a tendency for increased weight u p to 0.25 percent. In that growth on all feather meal diets was markedly inferior to growth on soybean oil meal diets, it seemed advisable to study the effect of method of processing on the nutritive value of feather meal when used as the sole source of protein. Methionine, lysine, t r y p t o p h a n and histidine supplements were used in all feather meal diets. The results of Experiment 13 show t h a t finely ground raw feathers promoted a very low rate of growth (Table 4). Chicks fed the diets containing the six processed samples grew a t a moderate rate. However, the group of chicks fed feather meal processed for 30 minutes under 30 p.s.i. showed a significantly lower growth rate ( p < . 0 5 ) t h a n those fed other experimentally processed samples. Thus, the sample processed for a period of 30 minutes under 30 p.s.i. (pepsin digestibility of 64 percent) appeared to be inferior to other treated samples (pepsin digestibilities of 70 to 83 percent). The d a t a suggest t h a t
1243
FEATHER MEAL PROCESSING AND SUPPLEMENTATION
there is some relationship of pepsin digestibility to the chicks utilization of feather protein. Commercial feather meals fed as the sole source of protein produced better growth than any of the laboratory processed meals. This finding emphasizes the importance of contamination by nonfeather substances and/or fermentation to the growth promoting properties of feather meal. Experiments conducted with basal ration 3 indicate that chick growth was poor when all the protein was supplied by a commercial feather meal in both 12 percent protein and 20 percent protein diets even though amino acids were supplied in quantities to meet the requirement given by the National Research Council (NRC). Growth rate was improved when the level of histidine was increased beyond the level needed to meet the NRC requirement. This indicated that either the histidine of feather meal TABLE 7.—Effect
was unavailable or the requirement is higher than 0.15 percent. Almquist (1956) and Rosenberg et al. (1957) reported the histidine requirement of the chick to be 0.3 percent of the diet. Supplementary histidine required to promote maximum growth in these trials plus that contained in the meal as reported by Gregory et al. (1956) approximates 0.3 percent. Failure to obtain maximum growth with amino acid supplementation indicates that some factor other than amino acid composition is responsible for poor results obtained with diets high in feather meal. Although assays indicate the presence of adequate amounts of glycine, leucine, isoleucine, threonine and valine in feather meal, it may be that one or more of these amino acids are limiting due to inability of the chick to digest and assimilate them from feather meal protein. Another possible reason for failure to
of amino acid supplementation on growth of chicks fed semipurified diets containing 20 percent protein from feather meal or soybean oil meal f Average body weights at 4 weeks (grams)
Amino acid supplement to basal ration 3 (%) Protein source in basal ration 3
Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Feather Meal Soybean Oil Meal 1
L-
Dt-
methio- L-lysine nine 0.33 0.46 0.33 0.33 0.33 0.33 0.33 0.46 0.46 0.46 0.46 0.33 0.33 0.33 0.33 0.33 0.33 0.30
0.74 0.74 1.18 0.74 0.74 0.74 0.74 1.18 1.18 1.18 1.18 0.74 0.74 0.74 0.74 0.74 0.74
histidine 0.06 0.06 0.06 0.15 0.06 0.06 0.06 0.06 0.06 0.15 0.15 0.10 0.175 0.20 0.225 0.25 0.30
DL
0.07 0.07 0.07 0.07 0.21 0.07 0.07 0.07 0.21 0.21 0.21 0.07 0.07 0.07 0.07 0.07 0.07
L-
. .
^
m D e
Glycine Expt. 101 104 113 112 196 99 100 112 112 113 220 212
0.42 0.30
0.42
Eighteen chicks per treatment. Twenty chicks per treatment. 3 Duplicate groups of sixteen chicks each per treatment.
2
"
tryptophenylphan alanine
0.30
Expt. II 2
Expt. 123
96 193
213
158 250
0.30
428
239 361
244 248 255 262 430
1244
E. C. NABER, S. P. TOUCHBURN, B. D. BARNETT AND C. L. MORGAN
obtain maximum growth on diets heavily dependent on feather protein might be the presence of toxic principles in feather meal. While this possibility cannot be overlooked, it appears unlikely because it was possible to obtain maximum growth with diets containing one-third of their protein from feather meal. It appears, therefore, that the most likely explanation for failure to obtain maximum growth on diets high in feather protein is poor amino acid availability. Further work is needed to clarify this point. SUMMARY
Properly processed feather meal was used to supply up to one-quarter of the crude protein in chick starting rations containing large amounts of protein from soybean oil meal and corn. Under these conditions, chick growth was excellent and dietary nitrogen utilization was not impaired. Contamination of feathers with offal and blood and/or fermentation of the feathers were found to be important factors influencing growth on feather meal diets. When feather meal was used to supply one-third or more of the total dietary protein, amino acid deficiency problems were encountered. In experimental diets where corn, soybean oil meal, and feather meal each contributed one-third of the crude protein, lysine and methionine supplementation were required to restore maximum growth rate. When one-half or more of the protein was contributed by feather meal, the amino acid deficiencies extended to tryptophan, histidine and perhaps other amino acids. Experimental processing of feathers for meal production showed that the method employed does affect the nutritive value of the product. One sample of feather meal containing 64 percent pepsin digestible protein was inferior to other samples
containing 70 to 83 percent pepsin digestible protein when fed to chicks as the sole source of protein. ACKNOWLEDGMENTS
The authors are grateful to the Byproduct Division of J. D. Jewell, Inc., Gainesville, Georgia and the SmithRowland Company, Norfolk, Virginia, for supplies of commercial feather meal. We wish to thank Dr. J. G. Davis, Poultry Laboratory, Western Utilization Research and Development Division, U. S. Department of Agriculture, Albany, California, for supplying the series of commercial and laboratory processed feather meal samples used in this work. Data on pepsin digestibility, nitrogen content and amino acid composition of the feather meals was also furnished by Dr. Davis. REFERENCES Almquist, H. J., 1956. Amino Acid Handbook by R. J. Block and K. W. Weiss, p. 164. Charles C Thomas, Springfield, Illinois. Binkley, C. H., and O. R. Vasak, 1950. Production of a friable meal from feathers. Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, U.S.D.A. Publication No. AIC-274. Bird, H. R., H. J. Almquist, W. W. Cravens, F. W. Hill and J. McGinnis, 1954. Nutrient requirements for poultry. Publication 301, National Research Council, Washington, D. C. Block, R. J., and D. Boiling, 1951. The Amino Acid Composition of Proteins and Foods. Charles C Thomas, Springfield, Illinois, Second Ed. Davis, J. G., 1958. Personal communication. Elmslie, W. P., 1958. A report on digestibility of proteins. J. Assoc. Off. Agr. Chem. 41: 233-240. Gerht, A. J., M. J. Caldwell and W. P. Elmslie, 1955. Chemical method for measuring relative digestibility of animal protein feedstuffs. J. Agr. Food. Chem. 3: 159-162. Gregory, B. R., O. H. M. Wilder and P. C. Ostby, 1956. Studies on the amino acid and vitamin composition of feather meal. Poultry Sci. 35: 234-235. Lillie, R. J., J. R. Sizemore and C. A. Denton, 1956. Feather meal in chick nutrition. Poultry Sci. 35:316-318.
FEATHER MEAL PROCESSING AND SUPPLEMENTATION Mangold, E., and J. Dubski, 1930. The digestion of keratin, especially the horny material of birds' feathers, by fowls and mammals. Wiss. Arch. Landw., Abt. B, Tierernahr. Tierzucht 4: 200221. McKerns, K. W., and E. Rittersporn, 1958. The nutritional significance of processed keratin in poultry feeding. Poultry Sci. 37: 433-436. Naber, E. C , and C. L. Morgan, 1956. Feather meal and poultry meat scrap in chick starting rations. Poultry Sci. 35: 888-895. Rosenberg, H. R., J. T. Baldini and C. I. Tollefson, 1957. Histidine requirement of the growing chick.
1245
Poultry Sci. 36: 1381-1382. Routh, J. I., 1942. Nutritional studies on powdered chicken feathers. J. Nutr. 24: 399-404. Sullivan, T. W., and E. L. Stephenson, 1957. Effect of processing methods on the utilization of hydrolyzed poultry feathers by growing chicks. Poultry Sci. 36: 361-365. Wilder, O. H. M., P. C. Ostby and B. R. Gregory, 1955. The use of chicken feather meal in feeds. Poultry Sci. 34: 518-524. Wisman, E. L., C. E. Holmes and R. W. Engel, 1958. Utilization of poultry by-products in poultry rations. Poultry Sci. 37: 834-838.
Reinvestigation of the Vitamin A Requirements of Laying and Breeding Hens and Their Progeny F. W. HILL, 1 M. L. SCOTT, L. C. NORRIS AND G. F. HETJSER2 Department of Poultry Husbandry, Cornell University, Ithaca, N. Y. (Received for publication November 4, 1960)
O
N THE basis of the available evidence from quantitative studies, the Committee on Animal Nutrition of the National Research Council (1954) has estimated the vitamin A requirements to be 1,200 U.S.P. units per pound of diet for growing chickens, and 2,000 U.S.P. units per pound of diet for laying and breeding hens. The results of individual studies on which these estimates are based have varied widely. The sources of vitamin A activity used in the various studies on requirement were fish oils, alfalfa meals and/or yellow corn, all of which were unstable to some degree, especially after mixture in the experimental diets. Even with the precaution of frequent diet mixing, the instability of the vitamin or its precursors introduced considerable uncertainty into the quantitative estimates of requirement.
1 Present address: Department of Poultry Husbandry, University of California, Davis, California. 2 Present address: 608 Hillside Drive, Lakeland, Florida.
Recently, efforts in industry have been directed toward the development of vitamin A preparations which are highly stable in diet mixtures and under adverse conditions of storage. Reinvestigation of the vitamin A requirements of hens and their progeny using one of these "stabilized" vitamin A preparations was considered appropriate because of the uncertainties concerned in earlier work and the wide variations in estimates derived from the different experiments. One of the abnormalities associated with vitamin A deficiency in hens is the production of eggs with a high incidence of blood spotting of the yolk (Bearse et al., 1960). This egg defect normally occurs in low incidence among commercial strains of chickens, but is known to be an inherited trait (Lerner et al., 1951). The studies to be described were undertaken to investigate the requirement of hens and their progeny for vitamin A, using a stabilized source of vitamin A and strains of chickens differing widely in their