determinations in parallel. Since no unusual equipment is required, the fallout cesium separation can be made in a general-purpose laboratory. It is expedient. however, not to conduct any part of the procedure in a laboratory used for radiotracer studies or to use glassware used for radioactive materials. T h e counting equipment used is commercially available. T h e size of the initial sample is set onl) by the Cs13’ level expected and the precision of measurement desired. .4 sample containing 25 picocuries of was necessary to give a count rate equal to background, when the equipment previously described was used and a n energ) bvidth of & 5 k.e.v. \vas counted.
Acknowledgment T h e author thanks D. A. Sullivan for help in developing this procedure, V. R. Bohman for providing some of the samples, and W. B. Dye for supplying some of the samples and advice. Literature Cited (1) Anderson, E. C.: Science 128, 882-6 ( 1958). (2) Booker, D . V.: Phjs. in Aled. Biol. 2, 29-35 (1957). (3) Ewing. R. E.. U. S. At. Energy Comm. HW-18146 (1950). (4) Kahn. B.. Smith, D. K . , Straub, C. P.! Anal. ChPm. 29, 1210-3 (1957). (5) Landford. J. C., U. S. At. Energy Comm. HW-49668 (1957). (6) Perkins. R. W., Ibid., HW-40544
C O T T O N S E E D M E A L I N P O U L T R Y FEED
(1955). (7) Spitsyn. V. I.. Mikheeva. N. B., A t o m n a i a Enere. 3. 255-8 119571. (8) Susic, hl. by.,Buii., Inst. .\‘uiiear Sci. “Boris Kidrich” (Belgrade) 7, 39-11 ( 1957). (9) \’an Dilla, M. A , , Los .4lamos Saiional Laboratory. personal communication: 1960. (10) Yamagata. S . . J . Chem. Snc. J a p a n , Pure Chem. Sect. 78, 513-7 (1957). (11) Yamagata, N.. M’atanabe, S.. Bull. Cheni. Soc. J a p a n 30, 580-3 (1957). Receirmed f o r reuiew September 6. 7960. -ICcepted January 10. 1.961. Dioi.rion of Aqricultural and Food ChPmistry. 138th Meeting, .4CS. .Yew York; S. I... September 1060. Study supported in part by the C’. S. Energv Commistion, Contract .4T(04-,?)-.3!Part B.
VERNON 1. FRAMPTON
Collaborative Study of the AGU Method of Grading Cottonseed Meals for Laying Rations
Southern Regional Research Laboratory, Agricultural Research Service, U. S. Department of Agriculture, N e w Orleans, La. and BlAGlO PICCOLO National Cottonseed Products Association Fellowship, Southern Regional Research Laboratory, N e w Orleans, La.
The results of a collaborative study of the available gossypol unit (AGU) method of grading cottonseed meals for laying rations indicate that significant differences exist in AGU values among eggs, birds, and meals. The correlation between the AGU values of cottonseed meals and coloration in yolks of stored shell eggs produced b y the meals is virtually zero. The AGU method may not be relied upon for grading cottonseed meals for laying rations.
A
L A R G E proportion of yolks from shell eggs from hens on cottonseed meal-containing diets develop a brown coloration when the eggs are stored under refrigeration conditions. Cottonseed meals vary widely in their ability to induce brown coloration in yolks of stored shell eggs. It was presumed by earlier \vorkers that coloration develops because of the “free” gossypol present in the meals ( 6 , 7, 70, 7 7 ) . .4pparently cottonseed meals cannot be graded for laying rations on the basis of their free gossypol contents? however, since the correlation between intensity of coloration in yolks and free gossypol content of the meals fed is poor ( 3 ) . A method for grading cottonseed meals for laying rations proposed by Grau (4. 5) depends upon a greater concentration in the yolks from eggs laid by cottonseed meal-fed hens of some acetone-hexane soluble material than that occurring in yolks from hens fed other rations. This acetone-hexane soluble material has an absorption maximum a t 440 mu. T h e absorption a t this wave length was ascribed by Grau
to a condensation product of gossypol and cephalin. T h e increased absorptivity of thr preparation obtained from cottonseed meal-produced yolk over that obtained with control yolk was proposed by him as a measure of the available gossypol in the cottonseed meal fed. More specifically, the AGU of a cottonseed meal was defined by the relatiomhip : AGU = [ r l ’ o o - A’4,Ul - [A”rtio - A ” G 0 l 7 c of material tested in ration x 100 where A ’ has reference to the absorbance of the extract from cottonseed mealproduced egg and A“ has reference to the absorbance of the extract from the control egg. Subscripts refer to the wave lengths at which the absorptivities are measured. A cottonseed meal having a n AGU of 0.30 or less was reported by Grau to be suitable for laying rations in amounts u p to 10% of the total ration. Large quantities of cottonseed meals have been used in laving rations for hens during the past 2 years, where the meals incorporated into the rations were
selected on the basis of the AGU testing method. T h e eggs produced were sold on the fresh egg market. .4 collaborative test of the AGU method became imperative because of the wide interest engendered by this use of cottonseed meals. These collaborating in the test weie: \*. P. Entwistle, Calif. Dept. .4gr. Sacramento, Calif.; C. R. Grau, Univ. of Calif., Davis, Calif.; A. .4.
Table 1. Per Cent Composition of Rations for Laying Hens Amount,
Constituent
%
Cottonseed meal Soybean meal Ground yellow corn Ground milo Alfalfa meal, dehydrated Ground limestone Bone meal Manganized salt Source of riboflavin equivalent to 500 unit/gram Source of vitamin A, 2,250 units; and vitamin D, 300 units/gram
10 15 15 49.4 2.5 3.5 3.5 0.5
V O L . 9, NO. 2, M A R . - A P R .
1961
129
0.3 0.3
widely in their ability to induce egg yolk discoloration in stored shell eggs were distributed to each of seven stations, where they were incorporated into laying rations and fed to laving hens. T h e ration formula is given in Table I. T h e control ration \vas prepared in an identical manner. excrpt that soybean meal completely replaced cottonseed meal. Hens that had not received cottonseed meal. oil, or soapstock for a t least 60 days prior to the initiation of the experi-
Heidebrecht, Paymaster Feeds, Abilene, Tex.; B. W. Heywang, U. S. Department of Agriculture, Glendale, biz. ; A. R. Kemmerer, Univ. of Ariz., Tiicson: Ariz.; C . H. Koons, Swift a n d Co., Chicago, Ill.; H . L. LYilcke, Ralston Purina Co., St. Louis! h l o . ; A . B. \Vatts, La. State Univ., Baton Rouge. La. Experimental Six cottonseed meals which diffpred
Table II.
Chemical Properties of Cottonseed Meals Used in laying Hen Rations €.Free Amino Gossypol, % lysine, Chemically G . 1 1 6 G . N uncombined Free
Meal No.
Type
Clf-100 101 102 103
Prepress solvent Screw press Prepress solvent Acetone extd. in Ib. Prepress solvent Prepress solvent
104 105
Table 111.
3 40 2 59
01 01 01 04
3 40 4 35
0 0 0 0
3 12 3 07
0 00 0 01
Nitrogen SOlU5ilifY.
rofoi
%
03
0 82
03
02 08
1 25 0 70 0 27
58 37 43 98
0 02 0 02
0 97 0 66
51 7 48 2
0 0 0 0
2 5
5 4
Average AGU Values Reported for Cottonseed Meals Sfofion
Meal
1
Chi-100 101 102 103 104 105
47 61 29 50 0 35 0 31
3
2
0 31 35 20 29 20 23
0 0 0 0
0 0 0 0 0
Table IV.
0 0 0 0 0 0
53 48 40 52 38 32
4 0 0 0 0 0 0
Vorionce, Source
Freedom, Degrees
Squares, Sum
1
Meals Hens
5 30 175 210 5 30 180 215 5 27 62 94 5 36 163 204 5 30 24
2,7297 0 5360 2,6332 5,8989 0.7198 0.6976 1.2236 2,6410 0.5951 0,6758 0.3470 1,6179 1,8233 1.8352 0.9410 5,2393 0.5435 0.4757 0.0605 1 ,0797 2.6234 1 ,7297 0.5089 4,8602 5,4984 1.1357 1 ,0948 7,7289
Total hieals Hens Eggs
2
Total
3
Meals Hens< E W d
Total 4
hieals
Hens Eggs Total Meals Hensc Eggsd
5
59 5 21 128 154 5 27 163 195
Total
6
Meals Hens Eggs Total
7
Meals Hensc Total
a
Ratio of variances.
130
b
40 58
34 53 34 36
0 0 0 0 0 0
26 53 16 30 24 15
7
6
47 61 34 56 27 28
0 0 0 0 0 0
0 0 0 0 0 0
47 62 13 44 31 18
A v.
0 0 0 0 0 0
42 54 26 45 30 26
Analyses of Variance of AGU Values
Sfofion No.
Eggs
5
Per cent probability.
Variance
F"
Pb
0 5459
30 50 1 19
0 0005 0 25
0,1440 0.0232 0.0068
6 21 3 41
0 0005 0 0005
0.1190 0.0250 0.0056
4 76 4 46
0 005 0 0005
0.3647 0.0510 0.0058
7 151 8 973
0 0005 0 0005
0,1087 0.0159 0.0025
6 84 6 36
0 0005 0 0005
0.5247 0.0823 0.0040
6 38 20 58
0 001 0 0005
1 ,0997 0.0421 0 0067
26 12 6 28
0 0005 0 0005
0.0179 0 0150
c
Hens in meals.
AGRICULTURAL AND FOOD CHEMISTRY
Eggs in hens in meals,
ment were used a t each station for each meal. They were maintained in individual cages having hardware cloth floors a n d were fed ad libitum. Although uniform numbers of hens a n d eggs were not studied a t all stations (cf. Table IV for degrees of freedom a t each station), all of the hens ivere initially fed the control ration. Starting on the tenth day on the control ration a m.n:mum of 12 eggs was collected from each hen a t most stations. Six of the eggs were used in the determination of the .4GU blank, a n d six lvere placed in cold storage in the shell to serve as control eggs 6 months later when all of the stored eggs \vere broken out to determine the degree of coloration developd u p m storage. T h e hens were then transferred to the cottonseed meal-containing rations and a t most stations 12 eggs were collected fromeach hen,starting 13 days later. Alternate eggs were used for AGU determinations; the others \
