Rapid Growth of Chickens Fed an Improved Semi-Synthetic Diet

Research Notes RAPID GROWTH OF CHICKENS FED AN IMPROVED SEMI-SYNTHETIC DIET L. J. MACHLIN AND R. S. GORDON Laboratory of Biochemistry and Nutrition, Monsanto Chemical Company, St. Louis 4, Missouri (Received for publication May 22, 1958)

Chicks diets consisting only of synthetic and/or highly purified ingredients are useful in evaluation of specific dietary ingredients. Purified diets used in the past rarely supported good growth. A diet which supports extremely rapid growth would facilitate the development of assays for various essential nutrients. Larger differences in growth should be expected between negative and positive control groups, and increased requirements for specific factors might also be found under these conditions. Furthermore such a diet would be useful in measuring genetic and environmental variation in different experiments or laboratories. We have found that the diet we have developed is highly uniform and does serve as a sensitive measure of extranutritional variation, besides providing optimal growth. A known semi-synthetic diet (Ritchey et ah, 1956) was modified mainly by increasing the dietary fat level and by the use of a different mineral mixture (Briggs et ah, 1952). The composition of this diet (S35) is given in Table 1. Day-old New Hampshire cockerels, obtained from a commercial hatchery, were divided at random into groups of 20 birds each and placed in wire-floored, electrically heated batteries. Chicks were reared in an airconditioned room, provided with continuous illumination, and offered experimental diets and water ad libitum. After 7 days birds were weighed individually and the heaviest and lightest birds in each group were discarded so that 12 chicks closest

TABLE 1.—Composition of diet S35 Ingredient Isolated soybean protein 1 Corn oil (Mazola)2 Salts "A" 8 Glycine Ground cellulose (Alphacel) Choline chloride Vitamin mixture (triturated in dextrose) 4 Penicillin concentrate (4 g. procaine penicillin per lb.) Vitamin A concentrate (20,000 I.U. per g) Vitamin D 3 concentrate (7,500 I.C.U. per g) Vitamin E concentrate (20,000 I.U. per lb.) Ascorbic acid Santoquin 5 Glucose (Cerelose) Methionine hydroxy analog (MHA) 6

% 35.0 16.0 6.0 1.0 1.0 0.2 0.5 0.05 0.05 0.02 0.02 0.025 0.0125 ' 39.5225 0.60 100.00

1 Assay Protein C-l, Archer-Daniels-Midland Company, Cincinnati, Ohio. 2 As each can was opened 1 mg./kilo of Tenox VI was added. This antioxidant mixture can be obtained from Eastman Chemical Products, Inc., Kingsport, Tennessee. 3 Contains in g. per 60 g. the following compounds, CaC0 3 , 15; K 2 HP0 4 , 9; Na 2 HP0 4 ) 7.3; Ca3 (P0 4 ) 2 , 14; NaCl, 8.8; MgS0 4 -7H„0, 5; ferric citrate, 0.4; MnS0 4 -4H 2 0, 0.42; KI, 0.04; ZnC0 3 , .02;CuSCv5H 2 O, 0.02. 4 This will supply in mg./kilo of finished diet: vitamin Bi2, 0.03; biotin 0.30; menadione, 1.0; pyridoxine HCl 8.0; folic acid, 4.0; riboflavin, 16.0; calcium pantothenate, 20.0; thiamine HCl, 24.0; nicotinic acid, 100.0. This mixture, Alphacel, and salts "A" can all be obtained from the Nutritional Biochemicals Corp., Cleveland, Ohio. 6 Registered trademark of the Monsanto Chemical Company for 6-ethoxy, 1,2-dihydro, 2,2,4trimethylquinoline (an antioxidant). 6 Registered trademark of the Monsanto Chemical Company for calcium
to the group mean remained. The chicks were weighed weekly thereafter.

1460

1461

RESEARCH NOTES

TABLE 2.—Growth of chickens fed purified diets Rations

Experiment No. 1, 27 days LC2M2+0.5% MHA 2 0 % casein diet s S35M«+0.5% M H A Experiment No. 2, 28 days S35M+0.6% MHA S 3 5 M + 0 . 6 % DL-methionine S 3 5 M + 0 . 6 % M H A + 1 . 0 % glycine S 3 5 M + 0 . 6 % M H A , 27.6% glucose deleted S 3 5 M + 0 . 6 % M H A , 27.6% glucose replaced with corn Experiment No. 3, 28 days S35M S 3 5 M + 0 . 3 % DL-methionine S35M4-0.4% DL-methionine S 3 5 M + 0 . 6 % DL-methionine S 4 4 M 5 + 0 . 5 % DL-methionine S 2 6 M « + 0 . 5 % DL-methionine

Weight' (gm.)

Gm. fee d consumed per gm. gain

446 (2) 500 (2) 567 (2)

1.64 1.41 1.24

602 (3) 589 (3) 565 (1)

1.36 1.42 1.60

550(1)

1.42

560(1)

1.33

412 (2) 537 (2) 603 (2) 618(2) 602 (2) 489 (2)

2.07 1.54 1.46 1.37 1.32 1.78

1 No. in parenthesis is No. of replicate groups of 12 cockerels each. 2 15% casein, 10% gelatin, 4% corn oil, 6% salts "A," vitamins and glucose to make 100%. 3 20% casein, 13.3% gelatin, 2% Alphacel, otherwise identical to S3 5. '6 S35M indicates that MHA has been deleted from diet S35. 43.7% Assay protein C-l, 1.25% glycine, otherwise identical 6to S35. 26.25% Assay protein C-l, 0.75% glycine, otherwise identical to S35.

The results in Table 2 demonstrate that chicks fed diet S35 will weigh 589-618 grams in 28 days. This growth is better than any observed with other purified or semi-synthetic diets used in this laboratory, whether of our own design or of other types reported in the literature.

Similar results have been obtained in another laboratory. 1 Substitution of corn meal for glucose, or changes in the protein level did not result in an increase in growth (see Table 2). The effect of modifying the vitamin levels has not yet been determined. From other experiments with more complex rations, we feel it is safe to assume that chicks fed diet S35 are still not growing to the limit of their genetic potential. Work is in progress to find appropriate additions or changes in the balance of nutrients which would result in a growth rate close to this estimated potential. REFERENCES Ritchey, S. J., H. M. Scott and B. C. Johnson, 1956. Adenosine and ash as unidentified chick growth factors in fishmeal. Proc. Soc. Exp. Biol. Med. 93:326. Briggs, G. M., M. R. Spivey, J. C. Keresztesy and M. Silverman, 1952. Activity of citrovorum factor for the chick. Proc. Soc. Exp. Biol. Med. 81: 113. 1 Using another strain of New Hampshire cockerels and crystalline vitamins A, D, and E, Dr. George Briggs of the National Institutes of Health has been able to confirm the superiority of diet S35 over other semi-synthetic or purified diets used in his laboratory.

A NOTE ON NEST PREFERENCE ROBERT E. WOODS 1 AND CHARLES K. LAURENT 2

Poultry Division, University of Georgia, Athens, Georgia (Received for publication August 1, 1958)

A series of observations was made of laying hens to gain further insight into their nesting habits. Approximately 250 pullets were observed once weekly over a 23-week period, beginning in October 1956 into March, 1957. Four 10 unit double1

Present address: Dahlonega Hatchery, Dahlonega, Ga. 2 Present address: Marbut Milling Company, Augusta, Ga.

deck nests were hung in a continuous row along one side of the pen. The row extended from a six foot aisleway at the rear of the house to within six feet of the front of the laying house which faced to the South and which remained open at all times. The nests in the top row were given odd numbers beginning with nest number one nearest the aisle to nest number 39 nearest the open front. Nests in the bot-