LIBRARY, A & M COLLEGE, CAMPU3, E-47-1132-6m-L180 TEXAS AGRICULTURAL EXPERIMENT STATIUN A. B. CONNER, DIRECTOR " A COLLEGE STATION, BRAZOS COUNTY, TEXAS BULLETIN NO. 462 NOVEMBER, 1932 DIVISION OF POULTRY HUSBANDRY Lime and Phosphoric Acid Requirements For Chicks AGRICULTURAL AND MECHANICAL COLLEGE OF TEXAS T. O. WALTON, President STATION STAFFT Administration: A. B. Conner, M. S., Director R. E. Karper, M. S., Vice-Director Clarice Mixson, B. A., Secretary . P. Holleman, Chief Clerk J. K. Francklow, Asst. Chief Clerk Chester Higgs, Executive Assistant Howard Berry, B. S., Technical Asst. Chemistry: ' . S. Fraps, Ph. D., Chief; State Chemist E. Asbury, M. S., Chemist F. Fudge, Ph. D., Chemist . C. Carlyle, M. S., Asst. Chemist L. Ogier, B. S., Asst. Chemist . J. Sterges, M. S., Asst. Chemist Ray Treichler, M. S., Asst. Chemist W. H. Walker, Asst. Chenist Velma Graham, Asst. Chemist Jeanne F._ DeMottier, Asst. Chemist R. L. Schwartz, B. S., Asst. Chemist C. M. Pounders, B. S., Asst. Chemist Horticulture: S. H. Yarnell, Sc. D., Chief **L. R. Hawthorn, M. S., Horticulturist H. M. Reed, B. S., Horticulturist J. F. Wood, B. S., Horticulturist L. E. Brooks, B. S., Horticulturist Range Animal Husbandry: J M. Jones, A. M., Chief B. L. Warwick, Ph. D., Breeding Investa. S. P. Davis, Wool Grader Entomology: F. L. Thomas, Ph. D., Chief; State Entomologist H. J. Reinhard, B. S., Entomologist R. K. Fletcher, Ph. D., Entomologist W. L. Owen, Jr., M. S., Entomologist IPHWPF/JQ Veterinary Science: *M. Francis, D. V. M. H. Schmidt, D. V. M., Veterinarian I. B. Boughton, D. V. M., Veterinarian **F. P. Mathews, D. V. M., M. S., Veterinarian W. T. Hardy, D. V. M., Veterinarian R. A. Goodman, D. V. M., Veterinarian Plant Pathology and Physiology: J. J. Taubenuhaus, Ph. D., Chief W. N. Ezekiel, Ph. D., Plant Pathologist W. J. Bach, M. S., Plant Pathologist C. H. Rogers, Ph. D., Plant Pathologist Farm and Ranch Economics: L. P. Gabbard, M. S., Chief W’. E. Paulson, Ph. D., Marketng C. A. Bonnen, M. S., Farm Management **W. R. Nisbet, B. S., Ranch Management A. C. Magee, M. S., Farm Management Rural Home Research: Jesse Whitacre, Ph. D., Chief Mary Anna Grimes, M. S., Textiles Elizabeth D. Terrill, M. A., Nutrition Soil Survey: T. Carter, B. S., Chief E. H. Templin, B. S., Soil Surveyor A. H. Bean, B. S§,Soil Surveyor R. M. Marshall, B. S., Soil Surveyor Botany: V. L. Cory, M. S., Acting Chief S. E. Wolff, M. S., Botanist Swine Husbandry: Fred Hale, M. S., Chief Dairy Husbandry: O. C. Copeland, M. S., Dairy Husbandry Poultry Husbandry: R. M. Sherwood, M. S., Chief J. R. Couch, B. S., Asst. Poultry Husbandman , Chief J. N. Roney, M. S., Entomologist Agricultural Engineering: J. C. Gaines, Jr., M. S., Entomologist H. P. Smith, M. S., Chief S. E. Jones, M. S., Entomologist Main Station Farm: F. F. Bibby, B. S., Entomologist G. T. McNess, Superintendent S. W. Clark, B. S., Entomologist Apiculture (San Antonio): “E. W. Dunnam, Ph. D., Entomologist H. B. Parks, B. S., Chief “R. W. Moreland, B. S., Asst. Entomologist A. H. Alex, B. S., Queen Breeder C. E. Heard, B. S., Chief Inspector Feed Control Service: C. Siddall, B. S., Foulbrood Inspector F. D. Fuller, M. S., Chief S. E. McGregor, B. S., Foulbrood Inspector James Sullivan, Asst. Chief Agronomy: S. D. Pearce, Secretary E. B. Reynolds, Ph. D., Chief J. H. Rodgers, Feed Inspector R. E. Karper, M. S., Agronomist K. L. Kirkland, B. S., Feed Inspector‘ P. C. Mangelsdorf, Sc. D., Agronomist S. D. Reynolds, Jr., Feed Inspector D. T. Killough, M. S., Agronomist P. A. Moore, Feed Inspector H. E. Rea, B. S., Agronomist E. J. Wilson, B. S., Feed Inspector B. C. Langley, M. S., Agronomist H. G. Wickes, B. S., Feed Inspector Publications: A. D. Jackson, Chief SUBSTATIONS No. 1, Beeville County: No. 9, Balmorhea, Reeves County: R. A. Hall, B. S., Superintendent J. J. Bayles, B. S., Superintendent No. 2, Lindale, Smith County: No. 10, College Station, Brazos County: P. R. Johnson, M. S., Superintendent R. M. Sherwood, M. S., In Charge "B. H. Hendrickson, B. S., Sci. in Soil Erosion “R. W. Baird, B. S., Assoc. Agr. Engineer No. 3, Angleton, Brazoria County: R. H. Stansel, M. S., Superintendent H. M. Reed, M. S., Horticulturist No. 4, Beaumont, Jefferson County: R. H. Wyche, B. S., Superintendent **H. M. Beachell, B. S., Jr., Agronomist No. 5, Temple, Bell County: Henry Dunlavy, M. S., Superintendent C. H. Rodgers, Ph. D., Plant Pathologist H. E. Rea, B. S., Agronomist S. E. Wolff, M. S., Botanist **H.V. Geib, M. S., Sci. in Soil Erosion **H. O. Hill, B. S., Jr. Civil Engineer No. 6, Denton, Denton County: P. B. Dunkle, B. S., Superintendent **I. M. Atkins, B. S., Jr. Agronomist No. 7, Spur, Dickens County: R. E. Dickson, B. S., Superintendent B. C. Langley, M. S., Agronomist No. 8, Lubbock, Lubbock County: D. L. Jones, Superintendent Frank Gaines, Irrig. and Forest Nurs. L. J. McCall, Farm Superintendent No. 11, Nacogdoches, Nacogdoches County: H. F. Morris, M. S., Superintendent **No. 12, Chillicothe, Hardeman County: “T. R. Quinby, B. S., Superintendent **J. C. Stephens, M. A., Asst. Agronomist No. 1A. bonora, Sutton-Edwards Counties W. H. Dameron, Superintendent I. B. Boughton, D. V. M., Veterinarian W. T. Hardy, D. V. M., Veterinarian O. L. Carpenter, Shepherd **O. G. Babcock, B. S., Asst. Entomologist No. 15, Weslaco, Hidalgo County: W. H. Friend, B. S., Superintendent S. W. Clark, B. S., Entomologist W. J. Bach, M. S., Plant Pathologist J. F. Wood, B. S., Horticulturist No. 16, Iowa Park, Wichita County: C. H. McDowell, B. S., Superintendent L. E. Brooks, B. S., Horticulturist No. 19, Winterhaven, Dimmit County: E. Mortensen, B. S., Superintendent **L. R. Hawthorn, M. S., Horticulturist Teachers in the School of Agriculture Carrying Cooperative Projects on the Station: G. W. Adriance, Ph. D., Horticulture S. W. Bilsing, Ph. D., Entomology V. P. Lee, Ph. D., Marketing and Finance D. Scoates, A. E., Agricultural Engineering A. K. Mackey, M. S., Animal Husbandry *Dean School of Veterinary Medicine. J. S. Mogford, M. S., Agronomy F. R. Brison, B. S., Horticulture W. R. Horlacher, Ph. D., Genetics J. H. Knox, M. S., Animal Husbandry A. L. Darnell. M. A., Dairy Husbandry tAs of September 1, 1932. "In cooperation with U. S. Department of Agriculture. There has been a tendency 0n the part of poultrymen during the last few years to increase the amount of minerals in their chick rations and it is probable that in many cases excessive amounts of minerals are being fed. Experiments were conducted in 1930 and 1931 to determine the lime and phosphoric acid requirements for growing chicks in order that definite recommendations regarding the use of minerals might be made. The results of these experiments show that the phosphoric acid requirement for greatest gain with chicks up to eight weeks of age is approximately 1.5 to 2.0 percent of the ration and the lime requirement is 1.5 to 3.0 percent. For chicks up to twelve weeks of age 1.1 to 1.2 percent of phosphoric acid and 1.3 to 1.9 percent of lime are required for greatest gain. These results indicate that the lime requirement for greatest gain is more exacting for the lower levels of phosphoric acid than for the higher levels studied. The mineral requirements recommended for normal gains in live weight also resulted in satisfactory calcification of the bones. With these amounts of phosphoric acid and lime for chicks up to twelve weeks old, there were more slipped tendons than with chicks receiving less phosphoric acid and more lime. However, later data at the Texas Station show that the basal ration selected was not satisfactory in that it did not contain the feeds necessary to pre- vent slipped tendons, and that the substitution of ten pounds of rice bran or twenty pounds of wheat gray shorts, or both, for an equal amount of yellow corn meal in the feed produced greater gains than the original ration. With this modification of the basal ration, and with the mineral levels recommended in these experiments the percentage of slipped tendons was reduced from 33 percent to 2 percent of the chicks. A forthcoming publication will report results of these experiments. CONTENTS Page Plan of Experiments _______________ -- 5 Experimental Results 6 Lime and phosphoric acid requirements when wheat gray shorts and cottonseed meal were fed Without dried buttermilk ______________ _- 6 Lime and phosphoric acid requirements when twelve percent of the ration consisted of dried buttermilk with no cottonseed meal or wheat gray shorts _______________________________________ i- 8 Lime and phosphoric acid requirements when eighteen percent of the ration consisted of dried buttermilk With no cottonseed meal or wheat gray shorts ______________________________ __ 9 Summary and Conclusions 13 Literature Cited 14 BULLETIN NO. 462 NOVEMBER, 1932 LIME AND PHOSPHORIC ACID REQUIREMENTS FOR CHICKS R. M. SHERwoon _ Studies on the calcium and phosphorous requirements for chicks have been _ ,_conducted by numerous workers. Those working with anti-rachitic rations Einclude Bethke (1, 2), Buckner (3, 4, 5), Halpin (6), Hart (7), Hunter (8), ‘iMassengale (9), Mussehl (10, 11), Titus (12, 13), Wilgus (14), and their iassociates. The Texas Agricultural Experiment Station started work ion this subject in 1930. The result of these experiments conducted during the spring of 1930 and the spring of 1931 are reported in this f-Bulletin. h PLAN OF EXPERIMENTS These experiments were planned to study further the mineral require- ‘ent for growing chicks. Four different series of experiments were onducted. The first consisted of five experiments carrying chicks from the day following hatching to six weeks of age and one experiment carrying j. chicks from the day following hatching to eight weeks of age. The Ether three series of experiments started with chicks the day following tching and carried them 12 weeks. All chicks used were Single Comb 3' hite Leghorns. All were brooded in battery brooders so arranged that fl lots in each experiment had as uniform conditions as could be sup- 'ed. The chicks were weighed individually at the beginning and the 1Q of the experiments and at two-week intervals during the experi- '_ents. They were weighed early in the forenoon after feed had been ‘thheld since six o’clock of the preceding day. The mixed rations used in the first series were analyzed for lime and Table 1. Percentage of Lime and Phosphoric Acid in Feeds Used in Series 2, 3, and 4.5‘ Feeds CaO P205 . w corn meal 0.02 0.71 »- buttermilk 2.20 2 19 i a. leaf meal 2.36 0.53 _» -- bone meal 33.34 25.65 u Shell 53.44 0.14 9' - lysis made under the supervision of Dr. Fraps, State Chemist. osphoric acid. In the second, third, and fourth series the individual >- _were analyzed for lime and phosphoric acid; the composition of __-.= is reported in Table 1. From these data the composition of h ration was computed. The feed was weighed to the chicks daily; they were allowed all _' would eat. Tap water was kept before them at all times. t the close of experiment 1 of the second, third, and fourth series the := bones of six representative cockerels from each ration were analyzed 6 BULLETIN NO. 462, TEXAS AGRICULTURAL EXPERIMENT STATION in the Division of Chemistry for the percent of ash in the water and fat-free bones. Throughout this Bulletin the term “unitsof feed to produce a unit of gain in live weight” includes maintenance requirements as well as feed for actual gains. In the tables which give gains, feed efficiency, analysis of the tibia bones, and the percent of chicks developing slipped tendons, the rations are arranged in the order of the magnitude of the mean gain in live weight. The mean weighted gain in live Weight as used in the second, third, and fourth series is one in which the pullets are weighted to cockerel weights. EXPERIMENTAL RESULTS Requirements Where Wheat Gray Shorts and Cottonseed Meal Were Fed Without Dried Buttermilk Six experiments were conducted in this series using rations in which most of the protein was secured from cottonseed meal and Wheat gray shorts. The rations used are shown in Table 2. Five experiments were conducted for six weeks and the sixth was continued for eight weeks. Table 2. Percentage of Ingredients in Chick Rations for Series 1. Ration Numbers 1 2 3 4 5 6 Yellow corn meal 57 55 58 56 54 54 Wheat gray shorts 20 20 20 20 20 20 Alfalfa leaf meal 5 5 5 5 5 Cottonseed meal (43% protein) _________________________________________ __ 13 13 13 13 13 13 Cod liver oil 2 2 2 2 2 2 Bone meal 0 0 1 1 1 3 Oyster shells 2 4 0 2 4 2 Salt 1 1 1 1 1 1 In this series of experiments, with chicks carried up to six and eight weeks of age, those which received the ration containing the largest amount of phosphoric acid, 2.01 percent, made the greatest average gains, as shown in Tables 8 and 4. Those making the next greatest average gains received the medium amount of phosphoric acid, 1.46 to 1.49 percent, while those receiving 1.14 to 1.16 percent of phosphoric acid made the poorest gains. The phosphoric acid requirement for these chicks is higher than for all other lots of chicks in this study. The data. from another experiment, as presented in Table 5, show that the phosphoric acid requirement is greater during the first eight weeks than for the period from the ninth to twelfth weeks, inclusive, or for the entire period. Thus the high phosphoric acid requirement in the first series of experiments, 1.46 to 2.01 percent, was probably due partially to the age limits of the chicks and possibly in part to the phosphoric acid carriers in the rations. The lime requirement is not as definitely shown in these experiments as is the phosphoric acid requirement. Through this limited feeding period with rations containing wheat gray shorts and cottonseed meal an intake of lime between 1.58 percent and 3.09 percent gave most rapid g. Series 1, six weeks. Table 3. Mean Gain in Grams and Units of Feed Per U11 (Cottonseed meal and wheat gray shorts.) LIME AND PHOSPHORIC ACID REQUIREMENTS FOR CHICKS _ _ it of Gain for the Various Rations, Rations arranged 1n order of magnitude cf gains in live weight. I 1 54W, i.’ Ration 6 I Ration 5 l Ration 4 l Ration 1 Ration 3 Ration 2 Oyster Oyster Oyster Oyster Oyster Oyster Shell 2% Shell 4% Shell 2% Shell 2% Shell 0 Shell 4% ._ Bone Bone Bone Bone Bone Bone Meal 3% Meal 1% Meal 1% Meal 0 Meal 1% Meal 0 Percent CaO in ration .......... .. 2.29 3.09 1.58 1.23 .63 2.53 '. Percent P205 in raton 2.01 1.49 1.46 1.16 1.47 1.14 5' CaO-PgOfi Ratio ...................... .. 1 :.88 1:.48 1 :.92 1 :.94 1 :2.33 1 :.45 f Experiment 1 ‘ Mean gain per chick .............. .. 205.5+ 190.81 178.81 186.4+ 185.21 163.81 3.6 4.7 4.3 4.9 4.4 3.2 " Units of feed per unit of gain 3.74 3.99 4.15 4.38 4.14 4.56 Experiment 2 Mean gain per chick .............. ._ 194.81 194.11 204.51 178.31 186.51 165.91 1 4.1 3.8 4.3 3.6 3.8 3.7 ~"' Units of feed per unit of gain 3.96 4.05 3.75 4.30 4.04 4.78 .1 Experiment 3 5 Mean gain per chick .............. _. 229.61 201.81 195.11 196.01 188.81 192.61 1' 4.1 4.1 4.7 4.2 3.3 4.4 k Units of feed per unit of gain 3.67 3.76 3.52 3.67 4.01 3.85 - Experiment 4 f. Mean gain per chick .............. _. 213.11 221.51 217.71 208.61 182.91 202.61 ~ 5.3 4.4 4.0 4.3 2.9 4.1 lUnits of feed per unit of gain 3.95 3.52 3.51 3.73 3.60 3.66 . Experiment 5 _ Mean gain per chick .............. .. 222.31 219.41 204.31 197.21 133.91 192.51 I 4.1 4.3 3.9 3.6 3.3 3.0 Units of feed per unit of gain 3.40 3.39 3.18 3.56 3.18 3.38 1 Mean of Exp. 1-5 , Mean gain per chick .............. .. 213.21 205.51 200.11 193.31 135.51 183.51 ' 2.0 2.1 2.0 1.9 1.6 1.8 Units of feed per unit of gain 3.71 3.72 3.60 3.90 3.83 3.98 Table 4. Mean Gain in Grams and Units of Feed per Unit of Gain for the Various -Rations, Series 1, eight weeks. Rations arranged in order of magnitude of gains in live weight. (Cottonseed meal and wheat gray shorts.) 1 Ration 6 Ration 4 | Ration 5 I Ration 1 l Ration 3 I Ration 2 3 Oyster Oyster Oyster Oyster Oyster Oyster i Shell 2% Shell 2% Shell 4% Shell 2% Shell 0 Shell 4% Bone Bone Bone Bone Bone Bone Meal 3% Meal 1% Meal 1% Meal 0 Meal 1% Meal 0 Percent CaO in ration ........ 2.29 1.58 3.09 1.23 i .63 2.53 Percent P505 in ration 2.01 1.46 1.49 1.16 1.47 1.14 i. CaO-P2O5 Ratio _______________________ .. 1 :.88 1 :.92 1 :.48 1 ..94 1 2.33 11.45 ‘ Mean gain per chick _____________ _. 345.11 326.61 315.81 306.21 299.31 269.01 . , 6.8 4.9 6.3 5.8 5.7 4.1 fpUnits of feed per unit of gain 3.65 3.75 3.98 3.99 4.12 4.81 V’ Table 5. Comparison of Gains in Live Weight in Grams at Different Periods of Growth on Different Phosphoric Acid Levels. (18 percent dried buttermilk.) Gain in Live Weight in Grams Bone meal Percent of é in ration Phosphoric Acid First eight Nine to twelve One to twelve in Ration weeks weeks inclusive weeks inclusive 2 1.43 272.3 457.0 I 729.3 1 1.18 266.4 513.2 779.6 0 .93 203.1 440.6 643.7 8 BULLETIN NO. 462, TEXAS AGRICULTURAL EXPERIMENT STATION gains on levels of 1.46 to 2.01 per cent of phosphoric acid. With phosphoric acid levels of only 1.14 to 1.16 percent the gains were better on a ration containing 1.23 percent of lime than on one containing 2.53 percent of lime. The lime requirement is more exacting on low phosphoric acid levels than on high phosphoric acid levels. No slipped tendons developed in this series of experiments, and no ash analyses were made of the bones. Requirements When Twelve Percent of the Ration Consists of Dried Buttermilk In the second series of experiments, six rations which contained 12 percent of dried buttermilk and different percentages of lime and phos- phoric acid were fed to duplicate lots of chicks for twelve weeks; the rations used are given in Table 6. In this series of experiments as well as in the third and fourth series, which were being conducted simultaneous- ly, the results obtained indicated that the basal rations were not satis- factory in that slipped tendons developed even though excessive amounts of phosphoric acid were not fed. It was later brought out by Titus (12) and Titus and Ginn (13) that rice bran protects chicks against slipped tendons when fed rations not containing an excessive amount of phos- phoric acid. Other results at the Texas Station to appear in a forth- coming publication show that wheat gray shorts, as well as rice bran, is of value in preventing slipped tendons. Hunter reports that with a basal ration consisting of corn meal 69 percent, wheat middlings 5 percent, alfalfa meal 3 percent, dried milk 15 percent, meat meal 21/; percent, fish meal 2% percent, bone meal 2 percent, and cod liver oil 1 per- cent, the percentage of hock trouble in battery brooding was at least 50 percent. When 20 parts of corn meal was replaced by a like amount of oat feed the hock trouble was prevented entirely. The addition of more bone meal to the basal ration caused as much as 90 percent hock trouble, and the elimination of the bone meal from the basal ration prevented hock trouble altogether. Table 6. Percentage of Ingredients in Chick Rations for Series 2. Ration numbers 1 2 3 4 5 6 Yellow corn meal 81 80 80 79 '78 77 Dried buttermilk 12 12 12 12 12 12 Alfalfa leaf meal 5 5 5 5 5 5 Salt_ _ _ _ % % % % Z1 f} Fortified cod liver oil H; 1A 1A 1A 4 4 Bone meal 0 0 1 1 2 2 Finely ground oyster shell ............................................... _. 1 2 1 2 2 3 It is noted from Table 7 that the rations containing 1.11 to 1.36 percent of phosphoric acid made the greatest gains, while those receiving .86 to .87 percent of phosphoric acid made the poorest gains. In this series chicks receiving a lime intake of 1.27 percent made greatest gains, followed by those receiving 2.13 percent of lime. On all levels of phosphoric acid the lower level of lime gave greatest gains. , Percentage of chicks which LIME AND PHOSPHORIC ACID REQUIREMENTS FOR CHICKS 9 The percentage of ash in the water and fat-free tibia bones was lower in the lots receiving the low amount of phosphoric acid than in the other lots, as shown in Table 7. There was no perceptible difference be- tween the percentage of ash in the bones of the lots receiving the medium and the largest amounts of phosphoric acid. Table 7. Mean Gain in Grams, Units of Feed per Unit of Gain, Percentage of Ash in Tibia Bones, and Percentage of Chicks Which Developed Slipped Tendons, Series 2, twelve weeks. Rations arranged in order of magnitude of gains in live weight. (12 percent dried buttermilk.) Ration 3 Ration 5 Ration 4 Ration 6 Ration 1 Ration 2 Oyster Oyster Oyster Oyster Oyster Oyster Shell 1% Shell 2% Shell 2% Shell 3% Shell 1% Shell 2% Bone Bone Bone Bone Bone Bone Meal 1% Meal 2% Meal 1% Meal 2% Meal 0 Meal 0 Percent CaO in ration ...... .- 1.27 2.13 1.80 2.67 .93 1.47 Percent P205 in ration ....... _. 1.12 1.36 1.11 1.35 .87 .86 CaO-P2O5 Ratio 1 :.88 12.64 1 :.62 1 :.51 1 :.93 1 :.59 Experiment 1 Mean weighted gain per chick 907.81 900.81 860.31 824.81 739.31 582.81 19.7 15.2 20.4 . 1 .1 Units of feed per unit of gain 3.35 3.56 3.50 3.68 3.70 4.05 Percentage of ash in water and fat free tibia bones 47.12 48.02 48.23 48.09 46.40 42.80 developed slipped tendons 20.8 8.7 4.2 8.0 12.0 12.0 Experiment 2 2,; Mean weighted gain per chick 803.11 765.31 803.31 747.21 715.01 566.81 20.9 . - 19.3 1.2 " Percentage of chicks which 22 6 13.2 10.1 1 Units of feed per unit of _gain 3.23 3.50 3.28 3.92 3.53 3.99 developed slipped tendons -_- 16.7 37.5 4.0 4.8 18.2 4.2 Mean of Exp. 1 & 2 Mean weighted gain per chick 855.51 833.11 831.81 776.11 742.21 573.81 14.4 13.6 14.1 12.4 11.7 9.8 Units of feed per unit of gain 3.30 3.54 3.40 3.79 3.63 4.02 Percentage of ash in water and fat-free tibia bones of Experiment 1 ......................... ._ 47.12 48.02 48.23 48.09 46.40 42.80 Percentage of chicks which developed slipped tendons ..._. 18.8 23.4 4.1 6.5 14.9 8.2 J The percentage of birds developing slipped tendons was greater in the lots receiving the largest amounts of phosphoric acid than in the lots receiving the medium or smaller amounts of phosphoric acid. The per- centage of chicks developing slipped tendons was lower in the lots re- ceiving the larger amounts of lime than in those receiving the smaller amounts of lime. Other results to appear in a forthcoming publication show that the slipped tendons on the medium and the low phosphoric acid rations could have been prevented by including rice bran or wheat gray shorts in those rations. Requirements When Eighteen Percent of the Ration Consists of Dried Buttermilk In this third series of experiments six rations which contained 18 percent of dried buttermilk and diiferent amounts of lime and phosphoric acid were fed to duplicate lots for 12 weeks. The rations used are shown , in Table 8. The difference between the rations in the second and third series is that in the second series twelve percent of each ration consisted 10 BULLETIN NO. 462, TEXAS AGRICULTURAL EXPERIMENT STATION of dried buttermilk, while in the third series eighteen percent of each ration consisted of this feed. In this third series of experiments, the chicks receiving a medium amount of phosphoric acid, 1.20 percent, made the highest average gains, as shown in Table 9. The second best amount of phosphoric acid is not definite. Table 8. Percentage of Ingredients in Chick Rations for Series 3. Ration numbers 1 2 3 4 5 6 Yellow corn meal 75 74 74 73 72 71 Dried buttermilk 18 18 18 18 18 18 Alftalfa leaf meal 5 5 5 5 5 5 a 4 4 4. 4 4 4. Fortified cod liver oil Z; Z; Z; Z; Z; Z4 Bone meal 0 0 1 1 2 2 Finely ground oyster shell 1 2 1 2 2 3 Table 9. Mean Gain in Grams, Units of Feed per Unit of Gain, Percentage of Ash in Tibia Bones, and Percentage of Chicks Which Developed Slipped Tendons, - Series 3, twelve weeks. Rations arranged in order of magnitude of gains in live weight. (18 percent dried buttermilk.) Ration 3 l Ration 4 I Ration 1 | Ration 5 Ration 6 I Ration 2 Oyster Oyster Oyster Oyster Oyster Oyster Shell 1% Shell 2% Shell 1% Shell 2% Shell 3% Shell 2% Bone Bone Bone ' Bone Bone , Bone Meal 1% Meal 1% Meal 0 Meal 2% Meal 2% Meal 0 Percent CaO in ration .......... .. 1.40 1.93 1.06 2.26 2.80 1.60 Percent P205 in ration 1.20 1.20 .95 1.45 1.44 .95 _ CaO-P2O5 Ratio ...................... .. 1:.86 1:.62 1:.90 1:.64 1:.52 1:.59 Experiment 1 Mean weighted gain per chick 979.4+ 955.01 888.31 880.11 834.01 792 91 24.3 24.3 15.4 32.7 _ 12.6 14.8 ' Units of feed per unit of gain 3.22 3.16 3.35 3.36 3.71 3.85 Percentage of ash in water ~ and fat-free tibia bones .... 49.26 48.17 46.44 49.05 48.46 46.31 Percentage of chicks which lieveloped slippel tendons 16.7 4.0 12.5 33.0 25.0 8.3 Experiment 2 Mean weighted gain per chick 893.81 855.31 820.11 738.31 764.81 698.11 22.5 18.9 16.5 16.8 20.3 Units of feed per unit of gain 3.10 3.22 3.26 3.23 3.32 3.81 Percentage of chicks which developed slipped tendons .... .. 19.0 12.5 27.3 45.5 57.1 8.0 Mean of Exp. 1 & 2 Mean weighted gain per chick 936.6+ 905.21 854.21 809.21 799.41 745.51 16.6 15.4 11.3 19. 10.5 12.6 Units of feed per unit of gain 3.17 3.19 3.31 3.31 3.54 3.83 Percentage of ash in water & fat-free tibia bones of Exp. 1 49.26 48.17 46.44 49.05 48.46 46.31 Percentage of chicks which developed slipped tendons 17.8 8.2 19.6 38.3 40.0 8.2 The rations in the third series contained more phosphoric acid than the corresponding rations in the second series. Possibly the amount of phosphoric acid in the third series, for the rations low in phosphoric acid is nearer correct than in the second series, and the other rations of the third series contain too much phosphoric acid. In other words, the rations in the third series containing the least amount of phosphoric acid may be better than the corresponding rations in the second series, and the rations in the third series containing the larger amounts of 5 I? g s’ I i 3 F r I I 5. a. E “i. iv‘ ‘is. studied, each with two levels of lime. LIME AND PHOSPHORIC ACID REQUIREMENTS FOR. CHICKS 11 phosphoric acid may not be as good as those in the second series. Prob- ably the optimum amount of phosphoric acid for greatest gains is between 1.1 percent and 1.2 percent. The lime requirement for greatest gain in this series of experiments is probably near 1.4 percent. In both experiments of the series the ration containing 1.4 percent of lime made greater gains than the ration con- taining 1.9 percent of lime. In this series of experiments the calcification of bones was slightly poorer from the birds which received rations containing the least amount of phosphoric acid, .95 percent. There was no difference observed in the calcification of bones between the rations containing 1.20 percent of phosphoric acid and those containing 1.45 percent of phosphoric acid. The percentage of birds developing slipped tendons was greater in the lots receiving the largest amount of phosphoric acid than in the lots receiving the medium or smaller amounts of phosphoric acid. The ' percentage of chicks developing slipped tendons was lower in the lots receiving the larger amounts of lime than in those receiving the smal- ler amounts of lime. In the third series of experiments three levels of phosphoric acid were In the fourth series the" same three levels of phosphoric acid were used as in the third series and each was studied with four comparable lime-phosphoric-acid ratios. These rations contained 18 percent of dried buttermilk as did those studied in the third series of experiments. The rations used in the fourth series, as given in Table 10, were fed to duplicate lots for a period of 12 weeks. Table 10. Percentage of Ingredients in Chick Rations For Series 4. Ration Numbers 1 2 3 4 5 6 7 8 9 I 10 i 11 l 12 Yellow corn meal ______________ _. 71.25 70.25 69.25 68.25 72.20 71.38 70.57 69.76 73.15 72.51 71.89 71.26 Dried buttermilk 18.00 18.00 18.00 18.00 18.00 18.00 18.00 18.00 18.00 18.00 18.00 18.00 i, Alfalfa leaf ’ ‘i meal .............. _. 5.00 5.00 5.00 5.00 5.00 5.00 5.00 5.00 5.00 5.00 5.00 5.00 .V Cod liver oil .... .. 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 2.00 t Salt ................... .. .75 .75 .75 .75 .75 .75 .75 .75 .75 .75 .75 .75 Bone meal _______ ._ 2.00 2.00 2.00 2.00 1.00 1.00 1.00 1.00 0.00 0.00 0.00 0.00 Finely ground oyster shell 1.00 2.00 3.00 4.00 1.05 1.87 2.68 3.49 1.10 1.74 2.36 2.99 : of phosphoric acid made the highest gains, as shown in Table 11. Q, which contained 1.42 to 1.44 percent of phosphoric acid made better gains than rations containing .93 to .94 percent of phosphoric acid, except ‘i’ in the case of those containing the least amount of lime. In this The chicks which received the rations containing 1.18 to 1.19 percent Rations 12 BULLETIN NO. 462, TEXAS AGRICULTURAL EXPERIMENT STATION m6 H6 M.“ Q2 ma“ w.“ Q8 “.3 9mm Nd Q3 adH ....28.E$ v.53? Haqomsww eeee ew... e... wwwewwe , H . NmH m . .0 3.2. “w? 2E.“ 3.9. 23H. 8.5. =3.“ 8.3 2....“ 3.8. mo...“ 0H5“ cwwwwmwwwowwmwwfiwwpwm 3.“ NHH“ w...“ 3.» w?“ “Qw w?" ma...“ mm.“ Héd 3“ bmfi Bu» Ho HHWHH non H68 we. muHGD. Ind l3: lvd |c.mH |o.HH lmzHH IwJH I32 [Hdm ||w.mH _ l. NHH .|o.mH +3.3 +QH$ +33 +5.2. +33 +35. +35. +2.3. +5.3. ‘THHQ. _ +1.3“. _ +3.3 VH2“? Hon 5mm H.032...» 56S . i Z w d. H dim Ho @535 NH. NH. NH. Q5 wdH m6 9mm odH 06¢ odH 06H 0d fmwwmwwwxwwmmmww wwfiowww nH . . a HQ Q...“ 2.“ E8 wQw Hmd “w...” 3w 3.“ 5.“ 3w 2.“ 3.» 5am we 3G5 Hon Haw“ mo mfiflp ||o.mH |H.._.H lvdH |H.mu IwdH |o.H.H In“: IQ“: Imam .|w.HN |H..Hw ulHdH +H$S +3.2. +§Hw +32. +Q2w +38 +5.5. +902. +§$ +Q2w +Q§w +33 “Home? Huh 59w wwebwm...» HSWQUSH w wcwiiwnxfl Q“ Q“ 3H Q3 Qw“. w.“ “.3 S.“ Q8 NH. Q2 Q2 éme%%mww wfimz“ wwwsfis. . x . we 0 mfiHwuHonH HHXMH“ “Q2. 00.5“ m3“. 5.8. QQ...“ =3.“ no.3. 2....“ 3.2. “Q2. 2....“ .... 1855 x33 wwbwfi HEN Hwfififi E an.» mo w wHnwonwnH 2.“. wed“ E8 .3.“ 3.“ “w...” a...” Him 3w .3.“ 5w vHd 736w we fiHHHH Hon 30w Ho 52D. |.. H.H.H || H..HH l“... | wdH | “.3 I32 .| “aw | 06H l: HdH I. cdH | Q3 |... “.5 +22. +ww$ 1T Q8“. |T “Q26 +33. +32. +22. +5“; 1T Haw“. +9.“; +18“. .138 M020 Hun 55M wwfimm...» =$H>H i i H fiHmEHHwQMH 31H N»; H 3.“ H w.“ H 31H 21H S." H EN." H mm." H um.“ H “w.” H 34H ....................... .. oHwwa wOfiWOwO “Q “Q Hé. i} w“; “H; w“; .3. 3H 2H 2H 2H ........ -- new“: E “cam “Ewnzwm mHd w: wHflH 3a mm.“ flaw 3d NHH 2.4 S.“ uHiH £4 ..... aosfi Hi OwO “awfiwm O H O H O H O H O H Q H O H O H O H O H O “mew... wmw“ w“ w“ w“ w“ m“ w“ mw w“ w“ w“ ww w“ w.“ w“ w“ w“ w“ w“ m“ w“ “e5 we?“ we?“ wew... wew“ wew... wew... “e5 wew“ wew“. wew... wew“ ...u.. U... 0 U... 0 U: Z Z: Z 7a I .8... Z 8... M H: Z U; I Z1 I 11 I T... w % % % % % W % % % % % % % % w % % % % % % % % _ NH HH oH N H. m m a H w m . w nomawfi floHwwM nomwwm HHOmHdum Gomwdfi nomvawH iomuafi floHuwmH G05 HHOS. H55 e nofiw . . . 3H . 5H . 3H e . m Asmfiwwwin H55. “£93m w: damn“? “fir: H; mHHmdM MO QQHHHHHHMNS MO HUUHO E UUNHHQHHG mflomudfi 6x003 w>Ho>5 J. mwHHow icowcoH wunaflw wwno |Ho>oQ s34? uMoHHHO we omwwnoouom HE.» iwnom n35. E Hi4 mo owwwcwouwm .530 no finD non wooh mo RHHGD 65x80 5 flaw “$05 .HH oEflH. LIME AND PHOSPHORIC ACID REQUIREMENTS FOR CHICKS l3 case the birds receiving the extreme phosphoric acid levels made the b same gains. The poorer growth of the other lots on the low phos- phoric acid intake was partially due to the excessive amounts of lime. Here again it is noted that the lime requirement for optimum gains is more bxacting on 10W phosphoric acid intakes than on high phos- phoric acid intakes. Rations containing 1.42 to 2.27 percent of lime made highest gains on phosphoric acid levels of 1.18 percent. The calcification of bones was poor in the chicks on the rations low 1 in phosphoric acid and high in lime, and satisfactory on the medium ._» and high phosphoric acid rations regardless of the lime intake. __ The percentage of chicks which developed slipped tendons was greatest in the lots receiving the rations containing the largest amount of phos- phoric acid and lowest in the lots receiving the rations containing the ilowest amount of phosphoric acid. The percentage of slipped tendons was lowest in the lots receiving the rations containing the largest amounts = of lime. SUMMARY AND CONCLUSIONS The phosphoric acid requirement for the first six or eight weeks is lhigher than for a period of twelve weeks. With the rations studied it iis shown that 1.5 to 2.0 percent of phosphoric acid, equivalent to .65 alto .87 percent of phosphorus, is required for normal growth and 1.5 to ;g3.0 percent of lime, equivalent to 1.07 to 2.14 percent of calcium, produces jligreatest gains. l With chicks grown to 12 weeks of age and receiving rations con- qtaining 12 to 18 percent of dried buttermilk, the phosphoric acid re- iquirement for satisfactory gain in weight is between 1.1 and 1.2 percent, iwhich is equivalent to .48 to .53 percent of phosphorus. The results of feeding twelve weeks are in close agreement with Wilgus p (14) but are higher than those found by Bethke (1, 2) and his associates, ~and Hart (7) and his associates. As pointed out by Wilgus, however, d the differences in the rate of gain in weight made by the chicks in the different experiments may explain this difference in the results. h The lime requirement under these conditions is between 1.3 and 1.9 per- . ent, which is equivalent to .93 to 1.36 percent calcium. These requirements are higher than those reported by Wilgus (14), Bethke and associates __. 1, 2), and Hart and associates (7). It is not known whether or not his higher requirement of lime is the result of the inadequate basal tion. If the basal ration used in these experiments were to be used j?» poultrymen it would be necessary to recommend larger amounts of 'me and less phosphoric acid in order to reduce the amount of slipped ndons. Other results at the Texas Station to appear in a forthcoming l blication show that this basal ration may be improved by the sub- E: ‘tution of 10 pounds of rice bran and 20 pounds of wheat gray shorts or 30 pounds of the yellow corn meal to the extent that very few 14 BULLETIN NO. 462, TEXAS AGRICULTURAL EXPERIMENT STATION chicks develop slipped tendons with the mineral requirements as recom- mended above. The phosphoric acid and lime requirements mentioned above for normal gains also result in satisfactory calcification of the bones. (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) LITERATURE CITED (Bethke, R. M., Kennard, D. C., Kick, C. H. 7 1929. The Availability of Calcium in Calcium Salts and Minerals .for Bone Formation in the Growing Chick. Poultry Science 9: 45-50. Bethke, R. M., Kennard, D. C., Kick, C. H., and Zinzalian, G. 1929. The Calcium-Phosphorus Relationship in the Nutrition of the Growing Chick. Poultry Science 8: 257-265. Buckner, G. D. and Martin, J. H. 1929. Calcium and Phosphorus Metabolism of the Growing Chick. Poultry Science 8: 284-289. Buckner, G. D., Martin, J. H., and Insko, W. M., Jr. 1929. the Growing Chick. Poultry Science 9: 1-5. Buckner, G. D., Martin, J. H., and Insko, W. M., Jr. 1930. The Calcium and Phosphorus Requirement of the Growing Chick. Poultry Science 9: 235-238. Halpin, J. G. and Lamb, A. R. 1932. The Effect of Ground Phosphate Rock Fed at Various Levels on the Growth of Chicks and on Egg Production. Poultry Science 11: 5-14. Hart, E. V., Scott, H. T., Kline, O. L., and Halpin, J. G. 1930. The Calcium-Phosphorus Ratio in the Nutrition of Growing Chicks. Poultry Science 9: 296-306. Hunter, J. E. 1932. Special Correspondence. Massengale, O. M. and Platt, C. S. 1930. The Efiect of Calcium from DiTerent Sources on the Growth and Egg Production of Poultry. Poultry Science 9: 240-246. Mussehl, F. E., Ackerson, C. W., and Blish, M.J. 1927. The Mineral Metabolism of the Growing Chick. Science 6: 239-242. Mussehl, F. E., Hill, R. F., Blish, M. J., and Ackerson, C. W. 1930. The Utilization of Calcium by the Growing Chick. Jour. Agr. Research 40: 191-199. Titus, H. W. 1932. Perosis, or Deforming Leg Weakness, in the Chicken. try Science 11: 117-126. Titus, H. W. and Ginn, W. M. 1931. Rice Bran, a Preventative of Perosis, Deforming Leg Weak- ness, in Chickens. Science 74: 249-250. Wilgus, W. S., Jr. 1932. The Quantitive Requirement of the Growing Chick for Cal- cium and Phosphorus. Poultry Science 10: 107-118. Poultry Poul- The Relative Utilization of Certain Calcium Compounds by