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Carcass Composition Studies
Carcass Composition Studies 2. I N F L U E N C E S O F B R E E D , S E X A N D D I E T O N G R O S S C O M P O S I T I O N O F T H E CARCASS A N D FATTY ACID COMPOSITION OF T H E ADIPOSE TISSUE HARDY M.
EDWARDS, J R . AND FRANCES DENMAN
Department of Poultry Science, University of Georgia, Athens, Georgia 30602 (Received for publication November 22, 1974)
POULTRY SCIENCE 54: 1230-1238, 1975
INTRODUCTION
S
TUDIES with rats (Mickelsen etal., 1955) and with mice (Fentonand Dowling, 1953; and Fenton and Marsh, 1956) have indicated strain differences in their body composition, particularly the amount of fat in the carcass. Schemmell et al. (1970) demonstrated large differences in body composition among seven strains of rats. Mitchell et al. (1926, 1931) presented data on growth and carcass composition of White Leghorn and White Plymouth Rock chickens indicating substantial differences in growth and fattening patterns. The White Plymouth Rock cockerels contained a greater percent of fat in their carcasses at every weight than the White Leghorn cockerels. The White Plymouth Rock pullets contained a higher percent fat than the White Leghorn pullets up to weights of three pounds; at weights greater than three pounds, the White Leghorn hens contained more fat on a percentage basis. Hunt (1965) showed that the body nitrogen:water ratio which is an index of body composition was different between two strains of chickens studied.
The objective of the studies reported herein was to determine if differences in body composition did exist among five strains of chickens of different historical or geographic origin. EXPERIMENTAL Experiment 1. One hundred twenty males and one hundred twenty females of the Light Brahma, White Plymouth Rock, Single Comb White Leghorn and Black Jersey Giant breeds; and seventy-two males and seventytwo females of the Dark Cornish breed were used in the experiment. 1 The birds were allotted to pens making 12 pens of each sex of each breed. The chicks were individually banded and housed in electrically heated battery brooders with wire mesh floors. Feed and water were supplied ad libitum. Four pens of each sex and breed were fed one of the three experimental rations shown in Table 1 for four weeks. After weighing and
1. All of the chickens utilized in experiment 1 were obtained from Murray McMurray Hatchery, Webster City, Iowa, 20595.
1230
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ABSTRACT A study was conducted to determine the effect of breed, sex and diet on the carcass composition of chickens. Male and female chicks of the Light Brahma, White Plymouth Rock, Single Comb White Leghorn, Black Jersey Giant and Dark Cornish breeds were fed three diets of widely varying calorie:protein ratios to four weeks of age. The Black Jersey Giant chickens attained the greatest weight at 4 weeks followed by the White Plymouth Rock, Dark Cornish and Single Comb White Leghorn with the Light Brahma growing the slowest of the strains tested. Significant differences in the quantity of moisture, protein, total lipid and ash present in the total carcass was found among certain breeds. The Light Brahma contained the largest amounts of total lipid, 10.4%, followed by the White Plymouth Rock, 10.2%, Black Jersey Giant, 9.5%, Single Comb White Leghorn, 8.8%, and the Dark Cornish, 8.6%. Both sex and diet also caused differences in the total body composition. Significant differences in the amounts of certain fatty acids in the carcasses of the various breeds were found; however, these differences were not great.
BODY COMPOSITION OF BREEDS TABLE 1.—Composition of diets Ingredients Ground yellow corn Soybean meal (dehulled) Poultry fat Fixed ingredients'
2
3
%
%
33.0
63.5
80.5
42.5 10.0 14.5
16.5 5.5 14.5
3.0 2.0 14.5
30 3300
20 3300
15 3300
110
165
220
1
Fixed ingredients included: poultry by-product meal 5%, dehydrated alfalfa 1.5%, ground limestone 0.5%, defluorinated phosphate (18% phosphorus and 33% calcium) 1.5%, salt 0.4%, trace mineral mixture 0.1%, vitamin mixture 0.4%, Zoamix® (contained 0.0125% Zoaline® 3, 5-dinitro-otoluamide), Dow Chemical Co., Midland, Michigan 0.05%, and Aureomycin® (contained 22 gm. chlorotetracycline/kg.) 0.05%. The trace mineral mixture had the following composition (%): Ca, 26.0; Mn, 6.0; Co, 0.04; Fe, 2.5; Cu, 0.2; Zn, 2.0 and I, 0.12. Vitamin premix furnished per kilogram of feed: retinyl palmitate, 4,4001.U.; vitamin D 3 ,880 I.U.; D-a-tocopheryl acetate, 11 I.U.; vitamin B 12 , 6.6 meg.; riboflavin, 4.4 mg.; calcium pantothenate, 8.8 mg.; niacin, 44.0 mg.; choline chloride, 220.0 mg.; 1,2- dehydroxy - 6 - ethoxy - 2 , 2 , 4 - trimethyl quinoline, 125.4 mg.; menadione sodium bisulfite, 2.2 mg. and methionine, 1.0 g.
recording feed consumption at four weeks, the birds were fasted for two hours, then one bird was taken from each pen for whole carcass analysis and another for fatty acid composition of adipose tissue. The bird for carcass analysis was sacrificed, weighed and stored in an air tight plastic bag in a freezer until it was removed, weighed, ground and analyzed for moisture, nitrogen, total lipid and ash. The percent moisture was determined from the percent weight after drying in a vacuum oven at 105° C. for 16 hours. Nitrogen was determined by the macro Kjeldahl method of the Association of Official Agricultural Chemists (1955). Protein was
expressed as Kjeldahl-N x 6.25. The percent ash was determined from the percent weight of the residue after heating in a muffle furnace at 500° C. for 16 hours. Total lipids were extracted from the carcass samples and the adipose tissue samples by the method of Folch et al. (1957). The methods used for preparing methyl esters, gas-liquid chromatography and qualitative and quantitative identification of the fatty acids have been described by Nugara and Edwards (1970). Statistical analysis of data was by analysis of variance and multiple range test of Duncan (1955). Experiment 2. Forty males and forty females of the White Plymouth Rock and Dark Cornish breeds were allotted to pens making four pens of each sex of each breed. The birds of two pens of each sex and breed were fed rations 1 or 3 (Table 1) for four weeks. Eleven White Plymouth Rock and nine Dark Cornish of each sex fed each dietary treatment were sacrificed and carcass composition determined as outlined under Experiment 1.
RESULTS AND DISCUSSION The influence of breed and diet on weight gain, feed efficiency and mortality in Experiment 1 is shown in Table 2. All the breeds except the White Plymouth Rock and Black Jersey Giant gained weight at significantly different rates; the average four week gain in weight for both sexes receiving all diets were: Light Brahma 194 g., Single Comb White Leghorn 246 g., Dark Cornish 302 g., White Plymouth Rock 321 g. and Black Jersey Giant 342 g. Sex also had a significant effect on growth rate with the four week weights for males being 291 g. and for females 271 g. Significantly different growth rates were produced by the three diets, the four week gain being 319 g. for diet 1, 304 g. for diet 2 and 220 g. for diet 3. There was highly significant interaction (P < 0.01) between
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Calculated analyses Protein, % M.E.,Cal./kg. Calorie :protein ratio
1
%
1231
1232
H. M. EDWARDS, JR. AND F. DENMAN
TABLE 2.—Effect Sex Females
Breeds'
Diets 2
4 week wt.
Feed/gain
Mortality
g. 235 381 304 387 384
g2.85 1.64 1.86 1.62 2.06
37.5 5.0 10.0 0.0 29.2
%
L.B. W.P.R. S.C.W.L. B.J.G. D.C.
1
L.B. W.P.R. S.C.W.L. B.J.G. D.C.
2
248 414 266 415 333
2.40 1.93 2.38 1.72 2.21
27.5 2.5 15.0 7.5 16.7
L.B. W.P.R. S.C.W.L. B.J.G. D.C.
3
192 278 217 286 249
2.81 2.42 2.82 2.24 3.29
30.0 2.5 2.5 2.5 12.5
L.B. W.P.R. S.C.W.L. B.J.G. D.C.
1
263 426 327 436 411
3.83 1.64 1.82 1.52 1.84
57.5 10.0 15.0 2.5 12.5
L.B. W.P.R. S.C.W.L. B.J.G. D.C.
2
252 396 298 417 364
2.16 1.90 2.13 1.72 2.41
17.5 0.0 7.5 5.0 25.0
L.B. W.P.R. S.C.W.L. B.J.G. D.C.
3
212 295 242 277 262
2.86 2.24 2.70 2.28 2.70
25.0 0.0 10.0 10.0 12.5
S.C.W.L. g275.9 2 334.4 Female 320.7
D.C. g333.5
W.P.R. g355.0
B.J.G. g369.8
Grouping of treatment results: 3 L.B. Breeds g222.6 Diet 3 250.9 Male Sex 302.0
1 348.8
'Breeds: L.B.—Light Brahma; W.P.R.—White Plymouth Rock; S.C.W.L.—Single Comb White Leghorn; B.J.G.—Black Jersey Giant; and D.C.—Dark Cornish. 2 Diets: All diets contained 3300 calories per kilogram. Diet 1, 2, and 3 contained 30, 20, and 15 percent protein, respectively. See Table 1 for detailed composition. 3 Two values not underscored by the same line are significantly different (P < 0.05).
breed and diet. This was probably caused by the very poor growth of the Light Brahma chickens that received the high protein diet. Neither sex nor diet had a significant effect on feed efficiency between the breeds in feed conversion, with the White Plymouth Rock and Single Comb White Leghorn showing the more efficient conversion of feed to gain. It is difficult for feed efficiency figures to
have much meaning when mortality is high and it was high in certain breeds in this experiment. The high mortality appeared to be due to two causes. The initial brooder temperature of 35° C. was definitely too high for a breed such as the Light Brahma. These birds appeared to be overheated at the start of the experiment and considerable mortality may have resulted from this apparent over-
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Males
of breed, diet and sex on weight gain, feed conversion and mortality
1233
BODY COMPOSITION OF BREEDS
TABLE 3.—The effect of breed, sex and diet on total carcass composition Percent of moisture, ash, protein and total lipid in the carcass of various breeds of chickens W.P.R.
S.C.W.L.
B.J.G.
D.C.
%
%
%
%
%
71.8±0.3 2 2.8±0.1 19.3±0.4 6.4±0.4
70.1±0.5 2.8±0.1 20.1±0.3 7.2±0.3
70.2±0.6 2.7+0.1 20.7±0.2 6.5±0.8
70.3±0.7 2.8+0.2 19.5±0.2 7.4±0.5
71.5±0.8 2.6±0.1 20.2±0.3 6.6±0.6
69.9±0.7 2.5+0.1 19.0±0.2 8.7±0.6
69.6+0.7 2.6±0.1 19.7±0.2 8.3±0.8
71.5+0.3 2.9±0.2 20.9±0.6 5.3±0.4
69.9±0.5 2.7±0.1 19.9±0.2 7.2±0.6
70.9±0.9 2.5+0.1 19.5+0.1 7.3±0.0
69.5±1.0 2.6±0.1 18.6±0.3 9.3±1.3
69.7±0.6 2.8±0.1 19.3±0.2 8.2±0.6
69.7±0.5 2.8+0.1 20.2±0.2 7.5±0.7
70.3±0.6 2.8+0.1 19.3±0.2 7.5±0.5
70.6±0.4 2.5+0.1 19.8+0.1 7.1 ±0.5
69.8+1.3 2.6±0.1 18.9±0.2 9.8+1.3
66.1±1.1 2.6+0.1 19.1+0.1 11.9+0.8
69.2±0.7 2.7±0.0 19.7+0.3 9.0±0.8
68.4+0.7 2.7±0.1 18.9+0.3 9.4±0.6
69.4±0.4 2.7±0.1 19.1 ±0.4 9.2±0.5
66.0±0.6 2.4±0.1 17.1±0.2 14.3+0.4
66.4±0.6 2.7±0.1 18.0+0.1 12.6±0.6
67.2±1.0 2.5±0.1 18.5+0.3 12.2+1.2
68.1+0.3 2.7±0.1 17.5±0.4 11.1+0.3
68.2±1.2 2.5+0.1 18.2±0.4 10.9+1.4
66.2±0.8 2.3±0.1 16.9±0.3 14.0±0.9
66.2±0.6 2.7±0.0 17.9±0.2 12.7±0.7
67.1 ±0.4 2.4±0.1 18.2+0.3 12.0±0.6
64.3±0.4 2.6±0.1 17.5±0.2 14.7±0.8
68.3±0.2 2.5+0.1 18.4±0.3 10.5±0.6
Grouping of treatment results when significant differences were found: 3 S.C.W.L. L.B. Moisture W.P.R. B.J.G. 69.2 68.7 Breeds 68.0 68.5 Sex
Female 68.4 3 66.8 L.B. 2.5
Male 69.3 2 69.2 D.C. 2.5
Sex
Female 2.6
Male 2.7
Diet
3 2.5
Protein Breeds
L.B. 18.3
2 2.7 B.J.G. 18.8
Sex
Female 18.9 3 17.8 D.C. 8.6
Diet Ash Breeds
Diet Total Lipid Breeds
D.C. 69.8
1 70.6 S.C.W.L. 2.6
W.P.R. 2.7
B.J.G. 2.7
1 2.7 W.P.R. 19.0
D.C. 19.2
S.C.W.L. 19.7
1 19.9 B.J.G. 9.5
W.P.R. 10.2
L.B. 10.4
Male 19.1 2 19.3 S.C.W.L. 8.8
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Diet 1 Males Moisture Ash Protein T.L. Females Moisture Ash Protein T.L. Diet 2 Males Moisture Ash Protein T.L. Females Moisture Ash Protein T.L. Diet 3 Males Moisture Ash Protein T.L. Females Moisture Ash Protein T.L.
L.B.'
1234
H. M. EDWARDS, JR. AND F. DENMAN
TABLE 3.—Continued
Sex
Male Female 9.0 10.0 Diet 1 2 3 7.1 8.9 12.5 'Breeds: L.B.—Light Brahma; W.P.R.—White Plymouth Rock; S.C.W.L.—Single Comb White Leghorn; B.J.G.—Black Jersey Giant; D.C.—Dark Cornish. 2 Average of 4 carcass samples. 3 Two values not underscored by the same line are significantly different (P < 0.05), none of the interactions were significant.
low protein diets with wide calorierprotein ratios produced the fatter birds. Significant differences in the ash content of the total carcasses were noted between some breeds and the high protein diets appeared to produce a bird with a higher ash content. Sex had no effect on the ash content of the carcass. Sex of the birds did not have any effect on the fat content of the adipose tissue or on the fatty acid composition of the adipose tissue lipids (Table 4). Diets had significant effects on the fat content of adipose tissue and in the lipid levels of palmitic acid (16:0), palmitoleic acid (16:1), stearic acid (18:0), linoleic acid (18:2), and linolenic acid (18:3). The low protein diet which also contained the lowest level of poultry fat had the highest amounts of 16:0 and 16:1 and the lowest levels of 18:2 and 18:3, it was intermediate in its 18:0 content. The high protein diet with its high level of poultry fat produced chickens with the highest level of 18:2 and 18:3 in the carcass. Breed showed significant differences in the myristic acid (14:0), 16:1, and 18:2 content of the adipose tissue lipids. These differences, while significant, were not large and the differences between the lowest and highest level found in a breed were 15-25% of the average value. In the second experiment the same relationship was found between White Plymouth Rock and Dark Cornish with regard to growth, feed conversion and mortality (Table 5). The Dark Cornish did not grow as fast in the second experiment and their growth was very
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heating. There was some mortality from leukosis and it appeared to affect some breeds more severely than others. The poor growth rate of the surviving Light Brahma was surprising in view of the fact that this breed is reported to attain such a large mature weight. The data on total carcass composition are presented in Table 3. Breed, sex, and diets all caused significant differences in the moisture content of total carcass. The White Plymouth Rock contained the least moisture with 68.00% while the Dark Cornish contained the most with 69.82% water in the carcass. Males contained significantly more water than females. The high protein diet with the narrow calorie:protein ratios produced birds with much more water in the carcass than the intermediate and low protein diets with wider calorie:protein ratios. Breed and diets both had significant effect on the protein content of the carcass while sex did not. The Light Brahma, a breed that at maturity is a giant chicken, contained the least protein while the Single Comb White Leghorn, a breed that at maturity is small among the non-bantam breeds, had the highest level of protein. The high protein diet with a narrow calorie :protein ratio always produced birds having the highest amount of protein in the total carcass. Breed, sex and diet had significant effects on the lipid content of the carcass. The Light Brahma and White Plymouth Rock contained the largest amount of lipid. The females contained more lipids than the males and the
1235
BODY COMPOSITION OF BREEDS
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Pi
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0\^'0'-^
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2 1.7
2 24.9
3 21.4
3 1.3
L.B. 23.4
B.J.G. 23.2
1 8.0
2 7.2
1 7.0
3 7.9
S.C.W.L. 7.3
2 18.9
D.C. 7.1
1 17.8
1 26.2
S.C.W.L. 24.0
2 9.0
3 9.0
W.P.R. 7.6
3 21.2
1 2.1 'Breed: L.B.—Light Brahma; W.P.R.—White Plymouth Rock; S.C.W.L.—Single Comb White Legh Cornish. 2 Abbreviations for fatty acids, first number indicates number of carbons and the second the number 3 Average of 4 samples of adipose tissue. "Total lipid. 'Two values not underscored by the same line are significantly different (P < 0.05).
18:3 Diets
Diets
18:2 Breeds
18:0 Diets
Diets
16:1 Breeds
16:0 Diets
TABLE 4.—Continued
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BODY COMPOSITION OF BREEDS
1237
TABLE 5.—The effect of breed, sex and diet on growth, feed conversion, mortality and total body composition (Experiment 2) Diet 3
Diet 1 Weight, 4 weeks, males—gm. (F/G)2 Weight, 4 weeks, females— gm. (F/G) Mortality, 4 weeks,, males—% Mortality, 4 weeks,, females—
W.P.R. 1
D.C.
W.P.R.
D.C.
436(1.65)
375(1.75)
290(2.62)
166(3.07)
375(1.81) 0
350(1.67) 4
262(2.67) 0
181(3.13) 16
0
5
0
12
%
68.7 b3 2.4" 18.8 b 10.4 b
± 0.7 ±0.1 ± 0.4 ± 0.9
71.6° 2.7 b 19.9C 6.7"
± ± ± ±
0.4 0.1 0.2 0.5
66.0" 2.4" 17.3" 14. l c
± ± ± ±
0.4 0.1 0.2 0.4
70.4° 2.5 a b 18.2 b 9.4 b
± ± ± ±
0.3 0.1 0.3 0.3
69.3" ± 0 . 4 2.6" ± 0.1 19.1° ± 0 . 2 9.7 b ± 0.4
70.9 b 2.5" 20.0 d 7.4"
± ± ± ±
0.3 0.1 0.2 0.3
64.8" 2.3" 16.9" 16.0C
± ± ± ±
0.9 1.0 0.2 1.0
69.6 b ± 0.6 2.4" ± 0.1 17.7" ± 0 . 3 10.7 b ± 0.7
'Breed: W.P.R.—White Plymouth Rock and D.C—Dark Cornish. F/G: Feed per gain. Values with different superscripts are significantly different (P < 0.05).
2
TABLE 6.—Effect
of breed, sex and diet on fatty acid composition of adipose tissue (Experiment 2) Diet 3
Diet 1 Fatty acid' 14:0 14:1 16:0 16:1 18:0 18:1 18:2 18:3
W.P.R. 2
W.P.R.
D.C.
D.C.
Males
Females
Males
Females
Males
Females
Males
%
%
%
%
%
%
%
%
1.0" 0.2" 19.4" 8.2 ab 7.9" 36.5" 25.6" 1.2"
1.3" 0.2" 19.1" 7.8" 8.5" 36.8" 25.3 b 1.1"
1.0" 0.1" 19.1" 7.4" 8.1" 37.5" 25.6 b 1.1"
0.8" 0.3" 22.6 b 9.6 cd 7.3" 38.1" 20.9" 0.6"
0.8" 0.2" 22.8" 10.2d 7.0" 38.8" 19.6" 0.7"
1.0" 0.1 a 22.6 b 8.8" 7.8" 38.1" 21.0" 0.6"
0.9" 0.1" 22.5 b 8.7 b 7.9" 38.3" 21.2" 0.5"
0.9"3 0.1" 19.9" 8.9*° 7.6" 37.4" 24.4 b 1.0"
Females
'Carbon chain length:number of double bonds. W.P.R.—White Plymouth Rock and D.C—Dark Cornish. Values in same row with different superscripts are significantly different (P < 0.05).
2 Breed: 3
poor on the low protein diet. In all comparisons except one the Dark Cornish had higher feed to gain ratios, and this may be associated with the slower growth rate. The body composition data on the White Plymouth Rock and Dark Cornish in Experiment 2 is very similar to that obtained in Experiment
1. The Dark Cornish is definitely a leaner bird with a higher moisture and protein content than the White Plymouth Rock. It would be very interesting to make this carcass composition comparison over the whole life of the bird, since Edwards et al. (1973) have shown that the amount of fat in the carcass
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Carcass composition Males Moisture % Ash% Protein % Lipid % Females Moisture % Ash% Protein % Lipid %
1238 increases
H. M. EDWARDS, JR. AND F. DENMAN
as the
bird
increases
in
size.
However, in the present study when the individual weights of birds and their percent lipid were subjected to a linear regression analysis, there was a negative correlation between weight and percent lipid content. Therefore, it does not seem that the increased percent lipid in the White Plymouth Rock is explainable on the basis of increased body size. The data on fatty acid composition of differences noted for diets in the first experiment, but did not confirm the higher level of myristic acid found in the Dark Cornish as compared to the White Plymouth Rock in the first experiment.
REFERENCES Association of Official Agricultural Chemists, 1955. Official Methods of Analysis. 8th ed., Washington, D.C. Duncan, D. B., 1955. Multiple range and multiple F tests. Biometrics, 11: 1-42. Edwards, H. M., Jr., F. Denman, A. Abou-Ashour and D. Nugara, 1973. Carcass composition studies. 1. Influence of age, sex and type of dietary fat
NEWS AND NOTES (Continued from page 1229)
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(Continued on page 1252)
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adipose tissue (Table 6) substantiated most
supplementation on total carcass and fatty acid composition. Poultry Sci. 52: 934-948. Fenton, P. F., and M. T. Dowling, 1953. Studies on obesity. I. Nutritional obesity in mice. J. Nutr. 49: 319-331. Fenton, P. F., and J. M. Marsh, 1956. Inherited metabolic patterns in mice. Caloric requirements for protein utilization and determination of protein minima. J. Nutr. 60: 465-472. Folch, J., M. Lees and G. H. Sloane Stanley, 1957. A simple method for the isolation and purification of total lipids from animal tissues. J. Biol. Chem. 226: 497-509. Hunt, J. R., 1965. Factors influencing body N : H 2 0 ratio of growing chicks. Poultry Sci. 44: 236-240. Mickelsen, O., S. Takahashi and C. Craig, 1955. Experimental obesity. I. Production of obesity in rats by feeding high-fat diets. J. Nutr. 57: 541-554. Mitchell, H. H., L. E. Card and T. S. Hamilton, 1926. The growth of White Plymouth Rock chickens. Illinois Agr. Exp. Sta. Bui. 278: 71-132. Mitchell, H. H., L. E. Card and T. S. Hamilton, 1931. A technical study of the growth of White Leghorn chickens. Illinois Agr. Exp. Sta. Bui. 367: 1-139. Nugara, D., and H. M. Edwards, Jr., 1970. Changes in fatty acid composition of cockerel testes due to age and fat deficiency. } . Nutr. 100: 156-160. Schemmel, R., O. Mickelsen and J. L. Gill, 1970. Dietary obesity in rats: Body weight and body fat accretion in seven strains of rats. J. Nutr. 100: 1041-1048.
EDWARDS, J R . AND FRANCES DENMAN
Department of Poultry Science, University of Georgia, Athens, Georgia 30602 (Received for publication November 22, 1974)
POULTRY SCIENCE 54: 1230-1238, 1975
INTRODUCTION
S
TUDIES with rats (Mickelsen etal., 1955) and with mice (Fentonand Dowling, 1953; and Fenton and Marsh, 1956) have indicated strain differences in their body composition, particularly the amount of fat in the carcass. Schemmell et al. (1970) demonstrated large differences in body composition among seven strains of rats. Mitchell et al. (1926, 1931) presented data on growth and carcass composition of White Leghorn and White Plymouth Rock chickens indicating substantial differences in growth and fattening patterns. The White Plymouth Rock cockerels contained a greater percent of fat in their carcasses at every weight than the White Leghorn cockerels. The White Plymouth Rock pullets contained a higher percent fat than the White Leghorn pullets up to weights of three pounds; at weights greater than three pounds, the White Leghorn hens contained more fat on a percentage basis. Hunt (1965) showed that the body nitrogen:water ratio which is an index of body composition was different between two strains of chickens studied.
The objective of the studies reported herein was to determine if differences in body composition did exist among five strains of chickens of different historical or geographic origin. EXPERIMENTAL Experiment 1. One hundred twenty males and one hundred twenty females of the Light Brahma, White Plymouth Rock, Single Comb White Leghorn and Black Jersey Giant breeds; and seventy-two males and seventytwo females of the Dark Cornish breed were used in the experiment. 1 The birds were allotted to pens making 12 pens of each sex of each breed. The chicks were individually banded and housed in electrically heated battery brooders with wire mesh floors. Feed and water were supplied ad libitum. Four pens of each sex and breed were fed one of the three experimental rations shown in Table 1 for four weeks. After weighing and
1. All of the chickens utilized in experiment 1 were obtained from Murray McMurray Hatchery, Webster City, Iowa, 20595.
1230
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ABSTRACT A study was conducted to determine the effect of breed, sex and diet on the carcass composition of chickens. Male and female chicks of the Light Brahma, White Plymouth Rock, Single Comb White Leghorn, Black Jersey Giant and Dark Cornish breeds were fed three diets of widely varying calorie:protein ratios to four weeks of age. The Black Jersey Giant chickens attained the greatest weight at 4 weeks followed by the White Plymouth Rock, Dark Cornish and Single Comb White Leghorn with the Light Brahma growing the slowest of the strains tested. Significant differences in the quantity of moisture, protein, total lipid and ash present in the total carcass was found among certain breeds. The Light Brahma contained the largest amounts of total lipid, 10.4%, followed by the White Plymouth Rock, 10.2%, Black Jersey Giant, 9.5%, Single Comb White Leghorn, 8.8%, and the Dark Cornish, 8.6%. Both sex and diet also caused differences in the total body composition. Significant differences in the amounts of certain fatty acids in the carcasses of the various breeds were found; however, these differences were not great.
BODY COMPOSITION OF BREEDS TABLE 1.—Composition of diets Ingredients Ground yellow corn Soybean meal (dehulled) Poultry fat Fixed ingredients'
2
3
%
%
33.0
63.5
80.5
42.5 10.0 14.5
16.5 5.5 14.5
3.0 2.0 14.5
30 3300
20 3300
15 3300
110
165
220
1
Fixed ingredients included: poultry by-product meal 5%, dehydrated alfalfa 1.5%, ground limestone 0.5%, defluorinated phosphate (18% phosphorus and 33% calcium) 1.5%, salt 0.4%, trace mineral mixture 0.1%, vitamin mixture 0.4%, Zoamix® (contained 0.0125% Zoaline® 3, 5-dinitro-otoluamide), Dow Chemical Co., Midland, Michigan 0.05%, and Aureomycin® (contained 22 gm. chlorotetracycline/kg.) 0.05%. The trace mineral mixture had the following composition (%): Ca, 26.0; Mn, 6.0; Co, 0.04; Fe, 2.5; Cu, 0.2; Zn, 2.0 and I, 0.12. Vitamin premix furnished per kilogram of feed: retinyl palmitate, 4,4001.U.; vitamin D 3 ,880 I.U.; D-a-tocopheryl acetate, 11 I.U.; vitamin B 12 , 6.6 meg.; riboflavin, 4.4 mg.; calcium pantothenate, 8.8 mg.; niacin, 44.0 mg.; choline chloride, 220.0 mg.; 1,2- dehydroxy - 6 - ethoxy - 2 , 2 , 4 - trimethyl quinoline, 125.4 mg.; menadione sodium bisulfite, 2.2 mg. and methionine, 1.0 g.
recording feed consumption at four weeks, the birds were fasted for two hours, then one bird was taken from each pen for whole carcass analysis and another for fatty acid composition of adipose tissue. The bird for carcass analysis was sacrificed, weighed and stored in an air tight plastic bag in a freezer until it was removed, weighed, ground and analyzed for moisture, nitrogen, total lipid and ash. The percent moisture was determined from the percent weight after drying in a vacuum oven at 105° C. for 16 hours. Nitrogen was determined by the macro Kjeldahl method of the Association of Official Agricultural Chemists (1955). Protein was
expressed as Kjeldahl-N x 6.25. The percent ash was determined from the percent weight of the residue after heating in a muffle furnace at 500° C. for 16 hours. Total lipids were extracted from the carcass samples and the adipose tissue samples by the method of Folch et al. (1957). The methods used for preparing methyl esters, gas-liquid chromatography and qualitative and quantitative identification of the fatty acids have been described by Nugara and Edwards (1970). Statistical analysis of data was by analysis of variance and multiple range test of Duncan (1955). Experiment 2. Forty males and forty females of the White Plymouth Rock and Dark Cornish breeds were allotted to pens making four pens of each sex of each breed. The birds of two pens of each sex and breed were fed rations 1 or 3 (Table 1) for four weeks. Eleven White Plymouth Rock and nine Dark Cornish of each sex fed each dietary treatment were sacrificed and carcass composition determined as outlined under Experiment 1.
RESULTS AND DISCUSSION The influence of breed and diet on weight gain, feed efficiency and mortality in Experiment 1 is shown in Table 2. All the breeds except the White Plymouth Rock and Black Jersey Giant gained weight at significantly different rates; the average four week gain in weight for both sexes receiving all diets were: Light Brahma 194 g., Single Comb White Leghorn 246 g., Dark Cornish 302 g., White Plymouth Rock 321 g. and Black Jersey Giant 342 g. Sex also had a significant effect on growth rate with the four week weights for males being 291 g. and for females 271 g. Significantly different growth rates were produced by the three diets, the four week gain being 319 g. for diet 1, 304 g. for diet 2 and 220 g. for diet 3. There was highly significant interaction (P < 0.01) between
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Calculated analyses Protein, % M.E.,Cal./kg. Calorie :protein ratio
1
%
1231
1232
H. M. EDWARDS, JR. AND F. DENMAN
TABLE 2.—Effect Sex Females
Breeds'
Diets 2
4 week wt.
Feed/gain
Mortality
g. 235 381 304 387 384
g2.85 1.64 1.86 1.62 2.06
37.5 5.0 10.0 0.0 29.2
%
L.B. W.P.R. S.C.W.L. B.J.G. D.C.
1
L.B. W.P.R. S.C.W.L. B.J.G. D.C.
2
248 414 266 415 333
2.40 1.93 2.38 1.72 2.21
27.5 2.5 15.0 7.5 16.7
L.B. W.P.R. S.C.W.L. B.J.G. D.C.
3
192 278 217 286 249
2.81 2.42 2.82 2.24 3.29
30.0 2.5 2.5 2.5 12.5
L.B. W.P.R. S.C.W.L. B.J.G. D.C.
1
263 426 327 436 411
3.83 1.64 1.82 1.52 1.84
57.5 10.0 15.0 2.5 12.5
L.B. W.P.R. S.C.W.L. B.J.G. D.C.
2
252 396 298 417 364
2.16 1.90 2.13 1.72 2.41
17.5 0.0 7.5 5.0 25.0
L.B. W.P.R. S.C.W.L. B.J.G. D.C.
3
212 295 242 277 262
2.86 2.24 2.70 2.28 2.70
25.0 0.0 10.0 10.0 12.5
S.C.W.L. g275.9 2 334.4 Female 320.7
D.C. g333.5
W.P.R. g355.0
B.J.G. g369.8
Grouping of treatment results: 3 L.B. Breeds g222.6 Diet 3 250.9 Male Sex 302.0
1 348.8
'Breeds: L.B.—Light Brahma; W.P.R.—White Plymouth Rock; S.C.W.L.—Single Comb White Leghorn; B.J.G.—Black Jersey Giant; and D.C.—Dark Cornish. 2 Diets: All diets contained 3300 calories per kilogram. Diet 1, 2, and 3 contained 30, 20, and 15 percent protein, respectively. See Table 1 for detailed composition. 3 Two values not underscored by the same line are significantly different (P < 0.05).
breed and diet. This was probably caused by the very poor growth of the Light Brahma chickens that received the high protein diet. Neither sex nor diet had a significant effect on feed efficiency between the breeds in feed conversion, with the White Plymouth Rock and Single Comb White Leghorn showing the more efficient conversion of feed to gain. It is difficult for feed efficiency figures to
have much meaning when mortality is high and it was high in certain breeds in this experiment. The high mortality appeared to be due to two causes. The initial brooder temperature of 35° C. was definitely too high for a breed such as the Light Brahma. These birds appeared to be overheated at the start of the experiment and considerable mortality may have resulted from this apparent over-
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Males
of breed, diet and sex on weight gain, feed conversion and mortality
1233
BODY COMPOSITION OF BREEDS
TABLE 3.—The effect of breed, sex and diet on total carcass composition Percent of moisture, ash, protein and total lipid in the carcass of various breeds of chickens W.P.R.
S.C.W.L.
B.J.G.
D.C.
%
%
%
%
%
71.8±0.3 2 2.8±0.1 19.3±0.4 6.4±0.4
70.1±0.5 2.8±0.1 20.1±0.3 7.2±0.3
70.2±0.6 2.7+0.1 20.7±0.2 6.5±0.8
70.3±0.7 2.8+0.2 19.5±0.2 7.4±0.5
71.5±0.8 2.6±0.1 20.2±0.3 6.6±0.6
69.9±0.7 2.5+0.1 19.0±0.2 8.7±0.6
69.6+0.7 2.6±0.1 19.7±0.2 8.3±0.8
71.5+0.3 2.9±0.2 20.9±0.6 5.3±0.4
69.9±0.5 2.7±0.1 19.9±0.2 7.2±0.6
70.9±0.9 2.5+0.1 19.5+0.1 7.3±0.0
69.5±1.0 2.6±0.1 18.6±0.3 9.3±1.3
69.7±0.6 2.8±0.1 19.3±0.2 8.2±0.6
69.7±0.5 2.8+0.1 20.2±0.2 7.5±0.7
70.3±0.6 2.8+0.1 19.3±0.2 7.5±0.5
70.6±0.4 2.5+0.1 19.8+0.1 7.1 ±0.5
69.8+1.3 2.6±0.1 18.9±0.2 9.8+1.3
66.1±1.1 2.6+0.1 19.1+0.1 11.9+0.8
69.2±0.7 2.7±0.0 19.7+0.3 9.0±0.8
68.4+0.7 2.7±0.1 18.9+0.3 9.4±0.6
69.4±0.4 2.7±0.1 19.1 ±0.4 9.2±0.5
66.0±0.6 2.4±0.1 17.1±0.2 14.3+0.4
66.4±0.6 2.7±0.1 18.0+0.1 12.6±0.6
67.2±1.0 2.5±0.1 18.5+0.3 12.2+1.2
68.1+0.3 2.7±0.1 17.5±0.4 11.1+0.3
68.2±1.2 2.5+0.1 18.2±0.4 10.9+1.4
66.2±0.8 2.3±0.1 16.9±0.3 14.0±0.9
66.2±0.6 2.7±0.0 17.9±0.2 12.7±0.7
67.1 ±0.4 2.4±0.1 18.2+0.3 12.0±0.6
64.3±0.4 2.6±0.1 17.5±0.2 14.7±0.8
68.3±0.2 2.5+0.1 18.4±0.3 10.5±0.6
Grouping of treatment results when significant differences were found: 3 S.C.W.L. L.B. Moisture W.P.R. B.J.G. 69.2 68.7 Breeds 68.0 68.5 Sex
Female 68.4 3 66.8 L.B. 2.5
Male 69.3 2 69.2 D.C. 2.5
Sex
Female 2.6
Male 2.7
Diet
3 2.5
Protein Breeds
L.B. 18.3
2 2.7 B.J.G. 18.8
Sex
Female 18.9 3 17.8 D.C. 8.6
Diet Ash Breeds
Diet Total Lipid Breeds
D.C. 69.8
1 70.6 S.C.W.L. 2.6
W.P.R. 2.7
B.J.G. 2.7
1 2.7 W.P.R. 19.0
D.C. 19.2
S.C.W.L. 19.7
1 19.9 B.J.G. 9.5
W.P.R. 10.2
L.B. 10.4
Male 19.1 2 19.3 S.C.W.L. 8.8
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Diet 1 Males Moisture Ash Protein T.L. Females Moisture Ash Protein T.L. Diet 2 Males Moisture Ash Protein T.L. Females Moisture Ash Protein T.L. Diet 3 Males Moisture Ash Protein T.L. Females Moisture Ash Protein T.L.
L.B.'
1234
H. M. EDWARDS, JR. AND F. DENMAN
TABLE 3.—Continued
Sex
Male Female 9.0 10.0 Diet 1 2 3 7.1 8.9 12.5 'Breeds: L.B.—Light Brahma; W.P.R.—White Plymouth Rock; S.C.W.L.—Single Comb White Leghorn; B.J.G.—Black Jersey Giant; D.C.—Dark Cornish. 2 Average of 4 carcass samples. 3 Two values not underscored by the same line are significantly different (P < 0.05), none of the interactions were significant.
low protein diets with wide calorierprotein ratios produced the fatter birds. Significant differences in the ash content of the total carcasses were noted between some breeds and the high protein diets appeared to produce a bird with a higher ash content. Sex had no effect on the ash content of the carcass. Sex of the birds did not have any effect on the fat content of the adipose tissue or on the fatty acid composition of the adipose tissue lipids (Table 4). Diets had significant effects on the fat content of adipose tissue and in the lipid levels of palmitic acid (16:0), palmitoleic acid (16:1), stearic acid (18:0), linoleic acid (18:2), and linolenic acid (18:3). The low protein diet which also contained the lowest level of poultry fat had the highest amounts of 16:0 and 16:1 and the lowest levels of 18:2 and 18:3, it was intermediate in its 18:0 content. The high protein diet with its high level of poultry fat produced chickens with the highest level of 18:2 and 18:3 in the carcass. Breed showed significant differences in the myristic acid (14:0), 16:1, and 18:2 content of the adipose tissue lipids. These differences, while significant, were not large and the differences between the lowest and highest level found in a breed were 15-25% of the average value. In the second experiment the same relationship was found between White Plymouth Rock and Dark Cornish with regard to growth, feed conversion and mortality (Table 5). The Dark Cornish did not grow as fast in the second experiment and their growth was very
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heating. There was some mortality from leukosis and it appeared to affect some breeds more severely than others. The poor growth rate of the surviving Light Brahma was surprising in view of the fact that this breed is reported to attain such a large mature weight. The data on total carcass composition are presented in Table 3. Breed, sex, and diets all caused significant differences in the moisture content of total carcass. The White Plymouth Rock contained the least moisture with 68.00% while the Dark Cornish contained the most with 69.82% water in the carcass. Males contained significantly more water than females. The high protein diet with the narrow calorie:protein ratios produced birds with much more water in the carcass than the intermediate and low protein diets with wider calorie:protein ratios. Breed and diets both had significant effect on the protein content of the carcass while sex did not. The Light Brahma, a breed that at maturity is a giant chicken, contained the least protein while the Single Comb White Leghorn, a breed that at maturity is small among the non-bantam breeds, had the highest level of protein. The high protein diet with a narrow calorie :protein ratio always produced birds having the highest amount of protein in the total carcass. Breed, sex and diet had significant effects on the lipid content of the carcass. The Light Brahma and White Plymouth Rock contained the largest amount of lipid. The females contained more lipids than the males and the
1235
BODY COMPOSITION OF BREEDS
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^ o d
Pi
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2 1.7
2 24.9
3 21.4
3 1.3
L.B. 23.4
B.J.G. 23.2
1 8.0
2 7.2
1 7.0
3 7.9
S.C.W.L. 7.3
2 18.9
D.C. 7.1
1 17.8
1 26.2
S.C.W.L. 24.0
2 9.0
3 9.0
W.P.R. 7.6
3 21.2
1 2.1 'Breed: L.B.—Light Brahma; W.P.R.—White Plymouth Rock; S.C.W.L.—Single Comb White Legh Cornish. 2 Abbreviations for fatty acids, first number indicates number of carbons and the second the number 3 Average of 4 samples of adipose tissue. "Total lipid. 'Two values not underscored by the same line are significantly different (P < 0.05).
18:3 Diets
Diets
18:2 Breeds
18:0 Diets
Diets
16:1 Breeds
16:0 Diets
TABLE 4.—Continued
m http://ps.oxfordjournals.org/ at Florida International University on June 17, 2015
BODY COMPOSITION OF BREEDS
1237
TABLE 5.—The effect of breed, sex and diet on growth, feed conversion, mortality and total body composition (Experiment 2) Diet 3
Diet 1 Weight, 4 weeks, males—gm. (F/G)2 Weight, 4 weeks, females— gm. (F/G) Mortality, 4 weeks,, males—% Mortality, 4 weeks,, females—
W.P.R. 1
D.C.
W.P.R.
D.C.
436(1.65)
375(1.75)
290(2.62)
166(3.07)
375(1.81) 0
350(1.67) 4
262(2.67) 0
181(3.13) 16
0
5
0
12
%
68.7 b3 2.4" 18.8 b 10.4 b
± 0.7 ±0.1 ± 0.4 ± 0.9
71.6° 2.7 b 19.9C 6.7"
± ± ± ±
0.4 0.1 0.2 0.5
66.0" 2.4" 17.3" 14. l c
± ± ± ±
0.4 0.1 0.2 0.4
70.4° 2.5 a b 18.2 b 9.4 b
± ± ± ±
0.3 0.1 0.3 0.3
69.3" ± 0 . 4 2.6" ± 0.1 19.1° ± 0 . 2 9.7 b ± 0.4
70.9 b 2.5" 20.0 d 7.4"
± ± ± ±
0.3 0.1 0.2 0.3
64.8" 2.3" 16.9" 16.0C
± ± ± ±
0.9 1.0 0.2 1.0
69.6 b ± 0.6 2.4" ± 0.1 17.7" ± 0 . 3 10.7 b ± 0.7
'Breed: W.P.R.—White Plymouth Rock and D.C—Dark Cornish. F/G: Feed per gain. Values with different superscripts are significantly different (P < 0.05).
2
TABLE 6.—Effect
of breed, sex and diet on fatty acid composition of adipose tissue (Experiment 2) Diet 3
Diet 1 Fatty acid' 14:0 14:1 16:0 16:1 18:0 18:1 18:2 18:3
W.P.R. 2
W.P.R.
D.C.
D.C.
Males
Females
Males
Females
Males
Females
Males
%
%
%
%
%
%
%
%
1.0" 0.2" 19.4" 8.2 ab 7.9" 36.5" 25.6" 1.2"
1.3" 0.2" 19.1" 7.8" 8.5" 36.8" 25.3 b 1.1"
1.0" 0.1" 19.1" 7.4" 8.1" 37.5" 25.6 b 1.1"
0.8" 0.3" 22.6 b 9.6 cd 7.3" 38.1" 20.9" 0.6"
0.8" 0.2" 22.8" 10.2d 7.0" 38.8" 19.6" 0.7"
1.0" 0.1 a 22.6 b 8.8" 7.8" 38.1" 21.0" 0.6"
0.9" 0.1" 22.5 b 8.7 b 7.9" 38.3" 21.2" 0.5"
0.9"3 0.1" 19.9" 8.9*° 7.6" 37.4" 24.4 b 1.0"
Females
'Carbon chain length:number of double bonds. W.P.R.—White Plymouth Rock and D.C—Dark Cornish. Values in same row with different superscripts are significantly different (P < 0.05).
2 Breed: 3
poor on the low protein diet. In all comparisons except one the Dark Cornish had higher feed to gain ratios, and this may be associated with the slower growth rate. The body composition data on the White Plymouth Rock and Dark Cornish in Experiment 2 is very similar to that obtained in Experiment
1. The Dark Cornish is definitely a leaner bird with a higher moisture and protein content than the White Plymouth Rock. It would be very interesting to make this carcass composition comparison over the whole life of the bird, since Edwards et al. (1973) have shown that the amount of fat in the carcass
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Carcass composition Males Moisture % Ash% Protein % Lipid % Females Moisture % Ash% Protein % Lipid %
1238 increases
H. M. EDWARDS, JR. AND F. DENMAN
as the
bird
increases
in
size.
However, in the present study when the individual weights of birds and their percent lipid were subjected to a linear regression analysis, there was a negative correlation between weight and percent lipid content. Therefore, it does not seem that the increased percent lipid in the White Plymouth Rock is explainable on the basis of increased body size. The data on fatty acid composition of differences noted for diets in the first experiment, but did not confirm the higher level of myristic acid found in the Dark Cornish as compared to the White Plymouth Rock in the first experiment.
REFERENCES Association of Official Agricultural Chemists, 1955. Official Methods of Analysis. 8th ed., Washington, D.C. Duncan, D. B., 1955. Multiple range and multiple F tests. Biometrics, 11: 1-42. Edwards, H. M., Jr., F. Denman, A. Abou-Ashour and D. Nugara, 1973. Carcass composition studies. 1. Influence of age, sex and type of dietary fat
NEWS AND NOTES (Continued from page 1229)
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of each calendar year will appear every September; a hard-bound, two-volume annual cumulation covering the review literature of the entire year will come out the following April. The first annual issue of I.S.R. covering review articles published in 1974 will appear in April, 1975. For further information contact the Institute for Scientific Information, 325 Chestnut Street, Philadelphia, Pennsylvania 19106. N.B.C. NOTES At the 20th annual conference of the National Broiler Conference held in Atlanta, Georgia, the following
(Continued on page 1252)
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adipose tissue (Table 6) substantiated most
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