The Availability of Phytic Acid Phosphorus for Chicks

880

E. C. NABER AND G. W. WARE

higher levels of both insecticides. Chicks hatching from eggs laid by Kepone-fed hens exhibited a nervous syndrome characterized by quivering extremities and inability to walk or stand. Survival of chicks from Kepone or mirex-fed hens was reduced. Egg yolk levels of the two insecticides reached a maximum on or before the fifth week of the experiment. High residues were found in egg yolks 3 weeks after termination of insecticide feeding.

1961 and 1962.

The Availability of Phytic Acid Phosphorus for Chicks 4. THE AVAILABILITY OF NATURAL PLANT PHOSPHORUS1 P. W. WALDROUP, C. B. AMMERMAN AND R. H. HARMS Florida Agricultural Experiment Stations, Gainesville (Received for publication November 16, 1964)

P

UBLISHED reports are not in complete agreement concerning the availability of the phosphorus in plant materials, commonly known as phytin phosphorus. 1 Florida Agric. Exp. Sta. Journal Series No. 2045.

Phosphorus extracted from various plant materials was poorly available for chicks and rats in studies reported by Lowe et al. (1939), Krieger et al. (1940, 1941), Spitzer et al. (1948), Gillis et al. (1949, 1957) and Matterson et al. (1946). However, the last group stated that one should not infer

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REFERENCES DeWitt, J. B., 1955. Effects of chlorinated hydrocarbon insecticides upon quail and pheasants. Agri. Food Chem. 3 : 672-76. DeWitt, J. B., D. G. Crabtree, R. B. Finley and J. L. George, 1962. Effects on wildlife, in U.S. Dept. of Interior, Bur. Sport Fisheries and Wildlife, Cir. 143, Effects of Pesticides on Fish and Wildlife in 1960. DeWitt, J. B., and J. L. George, 1960. U.S. Dept. of Interior, Bur. Sport Fisheries and Wildlife, Cir. 84, Pesticide-Wildlife Review. 1959. DeWitt, J. B., W. H. Stickel and P. F. Springer, 1963. Wildlife studies, Patuxent Wildlife Research Center, 1961-1962, in U.S. Dept. of Interior, Fish and Wildlife Service Cir. 167, Pesticide-Wildlife Studies, A Review of Fish and Wildlife Service Investigations During

Genelly, R. E., and R. L. Rudd. 1956. Effects of DDT, toxaphene, and dieldrin on pheasant reproduction. Auk, 73 : 529-39. Hill, P. I l l , 1962. The effects on bobwhite and coturnix quail from ingestion of Kepone-killed crickets, Kepone-peanut butter baits and imported fire ants. Master's thesis, Auburn University, Auburn, Alabama. 51 p. Naber, E. C , S. P. Touchburn and G. A. Marsh. 1961. Ohio Poultry Rations, Bulletin 343, Agricultural Extension Service, Ohio State University, Columbus. Ross, E., and M. Sherman, 1960. The effect of selected insecticides on growth and egg production when administered continuously in the feed. Poultry Sci. 39 : 1203-11. Rubin, M., H. R. Bird, N. Green and R. H. Carter, 1947. Toxicity of DDT to laying hens. Poultry Sci. 26: 410-13. Rudd, R. L., and R. E. Genelly, 1956. Pesticides: their use and toxicity in relation to wildlife. California Dept. Fish and Game, Game Bui. No. 7. Sherman, M., and E. Ross, 1961a. Acute and subacute toxicity of insecticides to chicks. Toxicol. Appl. Pharm. 3 : 521-33. Sherman, M., and E. Ross, 1961b. Toxicity to house fly larvae of droppings from chicks administered insecticides in feed, water and as single oral dosages. J. Econ. Ent. 54: 573-78. Ware, G. W., and E. C. Naber. 1961. Lindane in eggs and chicken tissues. J. Econ. Ent. 54: 675-677.

AVAILABILITY OF PLANT PHOSPHORUS

it was demonstrated by P32 tracer studies that phytin phosphorus can move freely about the body and participate in any reaction requiring phosphorus. Recent work at this laboratory has been directed toward factors which may explain the variation in reports concerning the utilization of plant phosphorus. Wide Ca:P ratios depressed the utilization of phytic acid phosphorus (Harms et al., 1962), while increased levels of vitamin D significantly increased the availability of calcium phytate phosphorus but not of sodium phytate or phytic acid phosphorus (Waldroup et al., 1964 b). In these studies it was also found that the addition of zinc to a practical diet had no effect on the utilization of phosphorus from three sources of phytin phosphorus. In addition, phosphorus from phytic acid was found to be as available as that from inorganic phosphates while phosphorus from sodium and calcium salts of phytic acid were found to be less available. Further studies by Waldroup et al. (1964 c) deomonstrated that the combination of low dietary calcium and increased vitamin D 3 supplementation significantly improved the utilization of the various salts of phytic acid. The present studies were conducted to determine the availability of phosphorus in various portions of the corn grain without chemical isolation or extraction. MATERIALS AND METHODS Three types of corn products were used as primary energy sources in a simplified chick feed to study the availability of plant phosphorus. These products were ground whole white corn, degerminated white corn meal, and hominy meal. The hominy meal is a by-product of corn meal manufacture and consists of a mixture of the corn bran, the corn germs, and a part of the starchy portion of the kernels. It is fully equal to corn in poultry diets (Morri-

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from the poor availability of the extracted plant phosphate that phosphorus of natural plant material is necessarily unavailable. The reports of Heuser et al. (1943) and McGinnis et al. (1944) suggested limited availability of phosphorus from plant sources. Gillis et al. (1949) indicated that phosphorus present in natural plant ingredients was a slightly more effective source of phosphorus than that extracted as calcium phytate. Singsen et al. (1947) reported that phosphorus in a mixture of cereal grains was relatively unavailable for bone calcification although the addition of vitamin D improved its utilization. Wheat bran phosphorus was poorly utilized by rats in the absence of vitamin D (Boutwell et al., 1946). However, an adequate intake of this vitamin increased the utilization of this phosphrous source for bone calcification nearly to that of inorganic phosphorus. The phosphorus in soybean meal was utilized by rats for both growth and bone formation (Spitzer and Phillips, 1945 a, b). Fritz et al. (1947) noted that under practical conditions cereal grain phosphorus was well utilized by turkey poults. The phosphorus in unifine flour was shown to be almost completely available for growth and somewhat less available for bone deposition in the chick (Sieburth et al., 1952). Vandepopuliere et al. (1961) reported that plant source phosphorus was readily available for growth in chicks when fed at an optimum Ca:P ratio of 1:1. A report by Harms et al. (1962) indicated that phytic acid phosphorus was as available to the chick as the phosphorus from dicalcium phosphate. Temperton and Cassidy (1964 a, b) concluded from balance studies that the chick was able to absorb and retain a large proportion of ingested plant phosphorus, and utilize this phosphorus for deposition in growing bones. This supports earlier work by Singsen et al. (1950) in which

881

882

P. W. WALDROUP, C. B. AMMERMAN AND R. H. HARMS

TABLE 1.—Phosphorus analysis of corn products Laboratory Corn Product 1

2

3

Ave.

% Phosphorus Degerminated corn Corn meal Hominy meal

0.09 0.26 0.61

0.09 0.25 0.63

0.11 0.28 0.59

0.10 0.26 0.61

TABLE 2.—Composition of diets Ingredient Degerminated corn White corn meal Hominy meal Corn oil Cerelose Soy protein Iodized salt Soybean meal (50% protein) Microingredients1 Variable2

Percent of Diet 1 59.7

2

3

—

— —

— — — — —

59.7

0.40

— — — —

0.40

41.0 4.45 13.34 0.91 0.40

34.00 0.90 5.00

34.00 0.90 5.00

34.00 0.90 5.00

22.40 % protein 3 Calories P.E./lb. 3 928.00 %P* 0.30 %Ca* 0.60

22.40 928.00 0.40 0.60

22.40 928.00 0.50 0.60

1 Supplied per kg. of feed: 1,320 I.C.U. vitamin D 3 , 6,930 I.U. vitamin A, 770 mg. choline, 40 mg. niacin, 4.4 mg. riboflavin, 20 mg. pantothenic acid, 22 meg. vitamin Bi2. 125 mg. ethoxyquin, 20 mg. iron, 2 mg. copper, 200 meg. cobalt, 11 mg. iodine, 100 mg. zinc, and 175 mg. manganese. 2 Consisted of reagent grade calcium carbonate, reagent grade monosodium phosphate, and pulverized oat hulls. 3 Calculated Analysis. 4 Chemical Analysis.

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son, 1959). All three ingredients were produced from the same sample of white corn. Samples of each ingredient were submitted to three laboratories for phosphorus and calcium analysis (Table 1). Basal diets were prepared using each of the three corn products (Table 2). A constant amount of soybean meal was used in order that the variation in phosphorus level of the diet would be a result of the corn component. Some adjustment of the hominy meal diet was necessary to maintain a constant level of energy and protein. Cerelose and corn oil were added to adjust for energy content and isolated soy protein added to adjust protein levels. Using an average of the analytical values for the three ingredients, the diets were calculated to contain 0.30, 0.40 and 0.50 percent phosphorus for the degerminated corn, white corn meal, and hominy meal diets, respectively. Chemical analyses of the diets by the three laboratories were in close agreement with calculated values. To each of the three basal diets, graded levels of inorganic phosphorus were added in the form of reagent grade monosodium phosphate (NaH 2 P0 4 • H 2 0). Phosphorus supplementation levels were 0, 0.10, 0.20, 0.30, and 0.40 percent, resulting in a 3 X 5 factorial arrangement of treatments. The total calcium content of all diets was held constant at 0.60 percent by the addition of calcium carbonate. This level of calcium supplementation met the calcium requirement of the 0-4 week old chick for this basal diet (Waldroup et al., 1964 a) with-

out creating a severe Ca:P imbalance in the diet. The supplemental vitamin D level was 1320 I.C.U. per kilogram of feed. Three successive feeding trials were conducted, using the original samples of the corn products to prepare the feeds for each trial. Chicks were maintained in electrically heated battery brooders with raised wire floors and offered the experimental feeds and tap water ad libitum. Day-old broiler chicks obtained from a local hatchery were sexed, debeaked, intraocularly vaccinated for Newcastle disease and infectious bronchitis, wing banded, and randomly assigned to pens. Ten chicks, equally divided as to sex, were assigned to each pen. In each of the three feeding trials, four pens were assigned to each dietary treatment, resulting in an overall total of twelve pens or 120 chicks per treatment. At twenty-eight days of age the chicks were individually weighed and two chicks of each sex were sacrificed from each pen

883

AVAILABILITY OF PLANT PHOSPHORUS

TABLE 3.—Twenty-eight day body weight of broiler chicks fed diets with plant phosphorus from three sources Plant Phosphorus Source Determinated Corn

Organic 1 Phosphorus

Total Phosphorus (%)»

(%)

0.30

0.30 M F

Hominy Meal

0.40

0.50

0.60

0.50 373 337

036 280 b

0.70

Body Weight (grams;)3 395 412 371 361 e

hi

0.80

0.90

-

-

308 (0.1)

355 (0.2)

392 '(0.3)

378S h (0.4)

M F

—

331 315

353 320

373 342

412 375

381 362

z

Av.

—

323"(0.0)

337d(0.1)

357 e (0.2)

394'i (0.3)

372 f *(0.4)

—

M F

_ -

432 372

396 373

397 367

388 350

Av. Corn Meal

294 263

0.40

Av.

278" (0.0)

—

402'(0.0)

385« (0.1)

hi

382« (0.2)

369

396 354 et

(0.3)

375 f e (0.4)

1 Values indicate the amount of organic phosphorus supplied by the all-vegetable diets. The remainder of the total dietary phosphorus is supplied by monosodium phosphate (NaH2P04H20). 2 Values in parentheses indicate the amount of inorganic phosphorus added to the all-plant diets. 1 Treatment means represent the average of 60 male and 60 female chicks in twelve replicate pens. Means bearing the same superscript do not differ significantly (P <0.05).

for bone ash determination. The right tibia was removed, cleaned of adhering tissue, and bone ash determined by the A.O.A.C. (1960) procedure. Statistical analyses of the data were conducted using the analysis of variance procedure outlined by Snedecor (1956) with significant differences between treatment means determined by the method of Duncan (1955). Analysis of the data indicated no significant trial X treatment interaction and permits discussion of the average results of the three trials.

RESULTS AND DISCUSSION

Organic plant phosphorus supplied in the diet as corn meal or hominy meal, was utilized as well as inorganic phosphorus in promoting body weight gains (Table 3). However, it was somewhat less available for calcification of bones (Table 4). As there was no sex X treatment interaction observed, discussion will be based on treatment average. Examination of the body weight data presented in Table 3 reveals that 0.10 percent organic plant phosphorus furnished by

TABLE 4.—Twenty-eight day tibia ash of broiler chicks fed diets with plant phosphorus from three sources Plant Phosphorus Source Degerminated Corn

Corn Meal

Organic Phosphorus

Total Phosphorus (%) 2 0.30

(%)> 0.30

M F

28.4 29.1

Av.

2 8 . 7 a (0.0)

0.40

M F

Av. Hominy Meal

0.50

M F Av.

1

— — — —

0.40

0.50

32.1 31.6

Tibia Ash Percent (%)» 37.8 38.5 39.9 37.6 38.3 39.1

3 1 . 9 b (0.1)

37.7de(0.2) 38.4e'(0.3)

39.5'(0.4)

30.1 33.4

31.8 33.7

37.3 38.0

b

31.7 (0.0)

— -

0.60

0.70

36.8 38.1 b

32.8 (0.1) 31.0 31.7 31.4b(0.0)

de

37.5 (0.2) 34.0 35.6 34.8C(0.1)

0.80

0.90

r

-

36.3 39.3 de

de

— —

37.6 (0.3)

37.8 (0.4)

35.9 36.8

35.4 36.4

35.4 36.5

35.9° (0.3)

35.9°(0.4)

od

36.3 (0.2)

Values indicate tha amount of organic phosphorus supplied by the all-vegetable diets. The remainder of the total dietary phosphorus is supplied by monosodium phosphate (NaHaP04H20). 2 Values in parentheses indicate the amount of inorganic phosphorus added to the all-plant diets. ' Treatment means expressed as percent ash of fat-free bone. Values are the average of 24 male and 24 female chicks in twelve replicate pens. Means bearing the same superscript do not differ significantly (P <0.05).

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-

hi

884

P. W. WALDROUP, C. B. AMMERMAN AND R. H. HARMS

degerminated corn diet produced tibia ash values that were equal to or significantly superior to corn meal or hominy meal diets containing equivalent levels of total dietary phosphorus but with greater amounts of organic phosphorus. The data from these studies demonstrates that organic plant phosphorus supported body weight gains equal to those obtained with inorganic phosphorus when the total dietary phosphorus level was below the minimum phosphorus requirement of the chick. At higher phosphorus levels there were few significant differences observed between any of the treatment groups. In contrast to the body weight data, the organic plant phosphorus was considerably less available for bone calcification than was inorganic phosphate even when the total phosphorus level of the diet was below the chicks' requirement. The phosphorus from hominy meal, which had promoted greater body weight gains than from corn meal, was less available for bone calcification than phosphorus from corn meal. While these results are in contrast to the reports of many previous workers concerning plant phosphorus availability, it must be stressed that calcium and vitamin D 3 supplementation of the experimental diets was expressly designed to permit maximum usage of the organic phosphorus as developed from earlier studies from this laboratory (Vandepopuliere et al, 1961; Harms et al, 1962; Waldroup et al, 1964 a, b). In addition, the organic phosphorus remained in its natural form in the plant material and was not chemically isolated. Results from this study which indicate that organic plant phosphorus is highly available for growth are in agreement with the reports of Sieburth et al. (1952) and Temperton and Cassidy (1964 a). The observation that the organic phosphorus was

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corn meal promoted significantly greater growth than 0.10 percent inorganic phosphorus added to a low-phosphorus basal diet composed of degerminated corn. However, in comparison to the low-phosphorus degerminated corn basal diet supplemented with 0.2 or 0.3 percent inorganic phosphorus, the 0.1 percent level of added organic phosphorus from corn meal supported significantly less body weight gains in diets having identical levels of total phosphorus. At total phosphorus level of 0.70 percent, the 0.1 percent organic phosphorus furnished by corn meal again significantly improved growth rate as compared to the low-phosphorus degerminated corn supplemented with inorganic phosphorus. Organic phosphorus supplied from hominy meal also supported body weight gains. A significant improvement in body weight was obtained when a basal diet containing 0.50 percent organic phosphorus using hominy meal was compared to 0.2 percent inorganic phosphorus supplementation of the degerminated corn diet to give a total phosphorus level of 0.50 percent. At higher levels of total dietary phosphorus the organic phosphorus from hominy meal was as effective in supporting body weight as that from the inorganic phosphorus source. The organic phosphorus from either corn meal or hominy meal was significantly less available for bone calcification than inorganic phosphorus (Table 4). When no supplemental inorganic phosphorus was added to the three all-plant diets, 0.1 percent additional organic phosphorus furnished by corn meal and 0.2 percent additional organic phosphorus from hominy meal significantly improved calcification as compared to the degerminated corn meal diet. No significant difference was observed between the corn meal (0.4 percent total phosphorus) and the hominy meal (0.5 percent total phosphorus) basal diets. Addition of inorganic phosphorus to the

AVAILABILITY OF PLANT PHOSPHORUS

SUMMARY Three trials involving 1800 broiler chicks were conducted to evaluate the availability of organic phosphorus without chemical isolation from the plant material. Degerminated corn, corn meal, and hominy meal prepared from the same sample of white corn were used to produce diets varying in amounts of organic plant phosphorus. Calcium and vitamin D 3 supplementation was designed to permit maximum utilization of the phosphorus source. Results indicate that the organic phosphorus was equal or superior to inorganic phosphorus in promoting body weight gains but was somewhat less available for bone calcification. ACKNOWLEDGMENTS This work was supported in part by a grant-in-aid from the Smith-Douglass Company, Inc., Norfolk, Virginia. The authors express their thanks to the Dixie Lily Milling Co., Williston, Florida, for preparing the products used in this study. REFERENCES Association of Official Agricultural Chemists, 1960. Official Methods of Analysis, 9th ed., Washington, D.C. Boutwell, R. K., R. P. Geyer, A. W. Halverson

and E. B. Hart, 1946. The availability of wheat bran phosphorus for the rat. J. Nutrit i o n a l : 193-202. Duncan, D. B., 19SS. Multiple range and multiple F tests. Biometrics, 11: 1-42. Fritz, J. C , J. L. Halpin and J. H. Hooper, 1947. Studies on the nutritional requirements of poults. Poultry Sci. 26: 78-82. Gillis, M. B., L. C. Norris and G. F. Heuser, 1949. The effect of phytin on the phosphorus requirement of the chick. Poultry Sci. 28: 283288. Gillis, M. B., K. W. Keane and R. A. Collins, 1957. Comparative metabolism of phytate and inorganic P32 by chicks and poults. J. Nutrition, 62: 13-26. Harms, R. H., P. W. Waldroup, R. L. Shirley and C. B. Ammerman, 1962. Availability of phytic acid phosphorus for chicks. Poultry Sci. 4 1 : 1189-1191. Heuser, G. F., L. C. Norris, J. McGinnis and M. L. Scott, 1943. Further evidence on the need for supplementing soybean meal rations with phosphorus. Poultry Sci. 22: 269-270. Krieger, C. H., R. Bunkfeldt and H. Steenbock, 1940. Cereals and rickets. X. The availability of phytic acid phosphorus. J. Nutrition, 20: 7-14. Krieger, C. H., R. Bunkfeldt, C. R. Thompson and H. Steenbock, 1941. Cereals and rickets. XIII. Phytic acid, yeast nucleic acid, soybean phosphatides, and inorganic salts as sources of phosphorus for bone calcification. J. Nutrition, 21: 213-220. Lowe, J. T., H. Steenbock and C. H. Krieger, 1939. Cereals and rickets. IX. The availability of phytin-P to the chick. Poultry Sci. 18: 4044. Matterson, L. D., H. M. Scott and E. P. Singsen, 1946. The influences of sources of phosphorus on the relative efficiency of vitamin D s and cod liver oil in promoting calcification in poults. J. Nutrition, 3 1 : 599-608. McGinnis, J., L. C. Norris and G. F. Heuser, 1944. Poor utilization of phosphorus in cereals and legumes by chicks for bone development. Poultry Sci. 23 : 157-159. Morrison, F. B., 1959. Feeds and Feeding, 22nd Ed., Clinton, Iowa. Sieburth, J. F., J. McGinnis, T. Wahl and B. A. McLaren, 1952. The availability of the phosphorus in unifine flour for the chick. Poultry Sci. 3 1 : 813-818. Singsen, E. P., L. D. Matterson and H. M. Scott, 1947. Phosphorus in poultry nutrition, III.

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less available for bone deposition confirms the report by Singsen et al. (1947) and Sieburth et al. (1952), but is in opposition to the findings of Temperton and Cassidy (1964 b). It is apparent from the results of this study that the availability of the phosphorus in plant materials may be much greater than generally assumed. Variation in the phophorus availability of different portions of the corn grain is indicated and may be responsible for some disagreement in results.

885

886

P. W. WALDROUP, C. B. AMMERMAN AND R. H. HARMS by balance experiments. British Poultry Sci. 5: 75-80. Temperton, H., and J. Cassidy, 1964b. Phosphorus requirements of poultry. II. The utilization of phytin phosphorus by the chick for growth and bone formation. British Poultry Sci. 5: 81-86. Vandepopuliere, J. M., C. B. Ammerman and R. H. Harms, 1961. The relationship of calcium: phosphorus ratios to the utilization of plant and inorganic phosphorus by the chick. Poultry Sci. 40: 951-957. Waldroup, P. W., C. B. Ammerman and R. H. Harms, 1964a. The utilization of calcium from different sources. Poultry Sci. 43: 212-216. Waldroup, P. W., C. B. Ammerman and R. H. Harms, 1964b. The availability of phytic acid phosphorus for chicks. II. Comparison of phytin phosphorus sources. Poultry Sci. 4 3 : 426-432. Waldroup, P. W., C. B. Ammerman, and R. H. Harms, 1964c. The availability of phytic acid phosphorus for chicks. III. Effect of calcium and vitamin D3 levels on the utilization of calcium phytate. Poultry Sci. 4 3 : 926-931.

NEWS AND NOTES (Continued from page 864) about 6 | years, Dr. Kingsbury was Technical Specialist for the Merck Chemical Division throughout eastern United States. Technical support to agricultural sales activities with considerable emphasis on coccidiosis utilized the majority of his time. From 1953 to 1957, Dr. Kingsbury was the first Extension Veterinarian in Poultry Health at the University of Connecticut. He is a major in the U. S. Army Reserve. REPRODUCTION CONGRESS At the closing session of the Fifth International Congress on Animal Reproduction and Artificial Insemination held in Trento, Italy, September 6-13, 1964, the following conclusions were drawn, and resolutions passed: 1) Our knowledge of antigenicity of gametes and its importance in fertilizaton failure and embryo mortality must be extended. Fetal-maternal incompatibility and their immune mechanisms are to be explored. 2) Research is needed on the mechanism whereby changes in environmental temperature, light, feed supply and social environment affect gonadal development and function.

3) Studies on the interaction of heredity and the many aspects of environment in determining reproductive performance are encouraged. They offer material highly suitable for analysis of mechanisms of reproduction and their modes of action. They also offer approaches for the development of animal husbandry as a true biological science: the control of environment in relation to the control of heredity, in this instance, to bring about the desired level of reproductive performance. 4) To continue studies of the physical, chemical, genetical and immunological mechanisms acting on spermatozoa in the female genital tract. 5) To continue studies for prolonging the reproductive capacity and increasing the economic potential of domestic animals. 6) To further study the hormonal and genetic factors which control animal production and reproduction. 7) To study the role of neuro-endocrine factors on reproduction. 8) To continue studies on the detection and synchronization of oestrus to reduce operational costs and permit the use of artificial insemination in areas not adapted for year-round operation.

(Continued on page 888)

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The relationship between the source of vitamin D and the utilization of cereal phosphorus by the poults. J. Nutrition, 3 3 : 13-26. Singsen, E. P., L. D. Matterson and A. Koseff, 1950. Phosphorus in poultry nturition. IV. Radioactive phosphorus as a tracer in studying the metabolism of phytin by the turkey poult. Poultry Sci. 29: 635-639. Snedecor, G. W., 1956. Statistical Methods, 5th Ed. The Iowa State College Press, Ames, Iowa. Spitzer, R. R., G. Maruyama, L. Michand and P. H. Phillips, 1948. The role of vitamin D in the utilization of phytin phosphorus. J. Nutrition, 35: 185-193. Spitzer, R. R., and P. H. Phillips, 1945a. The availability of soybean oil meal phosphorus for the rat. J. Nutrition, 30: 117-126. Spitzer, R. R., and P. H. Phillips, 1945b. Enzymatic relationships in the utilization of soybean oil meal phosphorus by the rat. J. Nutrition, 30: 183-192. Temperton, H., and J. Cassidy, 1964a. Phosphorus requirements of poultry. I. The utilization of phytin phosphorus by the chick as indicated