- Email: [email protected]
Physical Measurement Interrelationships of Turkeys Used in Further Processing1
392
ERNST, COLEMAN, KULENKAMP, RINGER AND PANGBORN
nix coturnix japonica) and embryogenesis of the domestic fowl. Ph.D. Thesis, Michigan State University, East Lansing, Michigan. Lucas, A. M., and C. Jamroz, 1961. Atlas of Avian Hematology. U. S. Dept. of Agriculture Monograph 25, Washington, D. C , 271 pp.
Nice, L. E., M. M. Nice and R. M. Kraft, 1935. Erythrocytes and hemoglobin in the blood of American birds. The Wilson Bulletin, 47: 120124. Sturkie, P. D., 1965. Avian Physiology, 2nd Ed. Cornell Univ. Press, Ithaca, N.Y.
Physical Measurement Interrelationships of Turkeys Used in Further Processing1
(Received for publication August 13, 1970)
T
URKEY carcass conformation may be expressed in terms of body weight, breast width, keel length, body depth, and other measurement standards. Geneticists have traditionally used these measurements as guides toward improving the market quality of breeding stock. Now with the advent of mechanized processing and deboning methods, measurement criteria must be reviewed and expressed in terms of their usefulness in developing automated processing machines and conveyorized deboning techniques. The objective of this study was to establish turkey physical measurement guidelines that would be useful to equipment manufacturers in their research and development. The interrelation of these physical measures are also presented. Latimer et al. (1926) present the general anatomical specifications and variability of the turkey hen. They found the percentage weights of the turkey viscera closely resembled the similar percentages in the chicken, but the musculature of the turkey was somewhat heavier. The skeleton weights 1
Research carried out under cooperative agreement between the University of California, Davis and the Transportation and Facilities Research Division, U.S. Department of Agriculture? 2 Current address: Division of Agriculture, Arizona State University, Tempe, Arizona 85281.
and the lengths of the long bones were less variable than many of the muscular parts of the body. Berg (1953) made a comprehensive analysis of deboned turkey meat yield and correlated meat yield to various body measurements. He noted that breast width measurement of live birds was highly correlated to meat yield. Body weight, breast width, and body depth were leading yield indicators. Body weight had the highest correlation coefficient to yield; but when body weight was held constant, body depth was the best indicator for predicting meat yield. Earlier work by Jaap and Penquite (1938) showed that the conformation of market poultry primarily determines its monetary value for human consumption. They stated that all linear measurements describing the conformation of dressed birds should be related to the body volume. The linear measurement compared to the cube root of body weight was a criterion of conformation. Another report by Jaap (1938) described a differential shape response of varieties to degrees of fleshing as noted in rib spread, anterior depth and shank length. Asmundson (1944) reported turkey breast width was correlated to body weight and strain. Sex and bird age affected the
Downloaded from http://ps.oxfordjournals.org/ at University of Georgia on May 25, 2015
P. G. STILES 2 AND A. W. BRANT University of California, Davis, California 95616
PHYSICAL MEASUREMENTS OF TURKEYS
EXPERIMENTAL
Physical measurements of eviscerated ready-to-cook carcasses and of deboned frames were taken in three separate commercial turkey processing plants. Carcasses were randomly selected from holding tanks. Fluid and ice were allowed to drain off prior to taking weights and measurements. A meter stick caliper and light-weight steel chain were used to take the following measurements: distance from pubis to clavical; width at the clavicals; distance from the ilium to the ventral point of the sternum; back width at the trochanter major of the femoral articulation; breast width at a depth of 2 cm. from the ventral point of the sternum; transverse circumference; median circumference omitting neck and tail; and maximum drumstick circumference. Eviscerated weight without neck and giblets was taken for each carcass and then the carcass was tagged and placed on the processing line for dismemberment. Each dismembered portion of the tagged carcass
was retrieved for further evaluation. Additional measurements included weight of each portion, femur length between distal points, sternum length including cartilage, sternum depth from the ventral process to a point where the frontal lateral portion of the sternum reaches a 30° angle to the median plane, and tibia length between distal points. Weights were accurate to within 1 gram, and distance over 10 cm. were accurate to within 1 cm. and those under 10 cm. within 0.1 cm. RESULTS AND DISCUSSION
Physical measurements descriptive of the bird's frame in relation to current deboning equipment and procedures are presented in Table 1. The groups represent the birds of the same sex, strain and class measured on the same day. They represent the variability among the common commercial stocks used for further processing. Maximum and minimum figures at the end of Table 1 are from the observed data only and do not necessarily represent the extremes that might be experienced if greater numbers of birds were studied. The data do indicate standards and tolerances that should be allowed in developing equipment and allowing for automated size adjustment. The means indicate the expected norm for each respective group. Tolerance allowances of four standard deviation units should be sufficient equipment adjustment variability for most automated equipment guides. Groups A and H represent one plant; B, C, D, F, J, K, and L a second plant; and E, G, and M a third plant. Groups A, B, C, D, E, and H were of the Broad Breasted Bronze variety while F, G, J, K, L, and M were Large Whites. The transverse circumference and the median circumference measurements exhibited the largest deviations about the mean. Other measurements did not vary to a great extent even though birds of differ-
Downloaded from http://ps.oxfordjournals.org/ at University of Georgia on May 25, 2015
physical measurements as shown by Swickard et al. (1954) and the fact that males have larger bones than females in proportion to their respective weights was found by Orr et al. (1956). Live body weight was cited by Leighton et al. (1961) as the most important single measurement for predicting meat yield in turkeys. Draper et al. (1961) reported body weight to be negatively correlated with dressing percentage while breast width was not correlated to dressing percentage but keel length was positively correlated to it. Hartung and Froning (1968) in a more recent study indicated edible meat yields of turkey carcasses are currently influenced by differences in sex, age, and strain. Physical measurements on chickens and their correlations to percent flesh were given by Maw et al. (1939) and the relation to automatic processing methods by Stiles (1967).
393
394
P. G. STILES AND A. W. BRANT TABLE 1.—Physical measurements of commercially deboned turkeys Pubis Sternum B Width Width t iJreast to Clavto at Clavof Width ical Ilium icals Back
Group
Transverse Circ.
Median Sternum Sternum Femur Tibia Circ. Length Depth Length Length
D
JH£gj£
CENTIMETERS 35.0 1.8
21.2 1.0
10.6 1.6
20.1 1.3
18.6 1.5
62.2 10.2
89.4 3.8
17.4 1.2
6.2 0.5
14.1 0.6
21.5 0.6
25.3 2.9
B (YT) BBB Mean Std. Dev.
IS 35.0 1.1
21.2 0.8
10.0 1.8
19.9 1.2
18.4 0.7
63.7 1.9
90.5 2.6
17.4 1.0
6.3 0.3
14.3 0.7
21.6 0.9
25.9 0.8
C (YT) BBB Mean Std. Dev.
20 35.0 1.8
22.0 1.0
10.8 1.3
21.0 0.9
18.0 2.7
63.0 3.2
93.6 3.4
17.6 0.6
6.2 0.4
13.8 0.6
21.5 0.6
25.5 2.5
D (YT) BBB Mean Std. Dev.
17 34.7 1.7
22.2 1.3
10.1 1.3
21.2 1.8
17.5 2.1
61.3 3.7
92.4 4.7
17.4 1.1
6.2 0.4
14.2 0.5
21.5 0.6
25.5 1.8
E (YH) BBB Mean Std. Dev.
17 29.0 0.7
18.0 0.6
8.3 1.1
16.2 0.7
15.4 0.9
51.5 1.4
77.4 1.5
15.2 0.8
5.4 0.4
11.8 0.5
18.0 0.5
20.2 0.7
F (YT) L W Mean Std. Dev.
26 34.5 1.3
22.1 0.9
11.0 1.0
21.6 1.4
17.5 1.0
63.2 3.2
92.8 3.2
18.2 0.7
6.1 0.4
14.3 0.6
21.3 0.7
27.1 0.1
G (BH) L W Mean Std. Dev.
27 30.2 1.4
19.5 1.1
10.3 1.1
17.8 0.8
16.2 1.0
56.8 2.8
83.8 3.1
15.7 1.0
5.9 0.4
12.2 1.6
18.2 0.6
24.1 1.2
H (YT) BBB Mean Std. Dev.
27 35.1 1.2
21.3 0.9
9.9 1.1
19.8 1.1
17.4 1.2
62.6 2.0
92.8 2.7
17.7 1.0
6.4 0.5
14.5 0.8
21.9 2.1
25.0 1.3
J
(YT) L W Mean Std. Dev.
22 35.2 1.5
22.4 1.0
9.4 1.2
21.6 1.1
17.0 0.8
62.5 1.9
93.1 2.3
18.4 0.8
68.4 0.4
14.6 0.5
21.6 0.8
26.5 1.4
K (BH) L W Mean Std. Dev.
22 30.6 0.6
19.4 1.0
8.9 1.2
17.5 1.0
16.0 1.0
54.6 2.8
81.7 3.3
15.7 0.6
5.7 0.3
12.0 0.4
17.7 0.5
24.1 1.1
L (YT) L W Mean Std. Dev.
20 34.2 2.9
22.5 1.0
9.3 1.5
21.4 1.1
16.9 1.0
63.6 2.8
93.3 2.3
18.2 0.7
6.6 0.5
14.5 0.6
21.8 0.9
27.1 1.4
M (YT) L W Mean Std. Dev.
10 32.8 1.8
22.6 0.8
8.7 1.3
19.1 1.2
16.2 1.4
61.9 3.1
89.3 4.9
17.6 1.6
7.1 0.4
14.6 0.6
22.0 0.9
26.0 2.0
24.8 14.8 19.8 2.1
21.5 14.2 17.7 2.1
70.7 49.5 60.5 7.1
102.0 75.0 88.8 6.6
20.5 14.4 17.1 1.3
7.7 4.7 6.1 0.1
16.3 10.9 13.7 1.1
24.1 16.7 20.9 1.5
29.6 19.3 24.5 2.9
Combined Groups 24.4 13.5 Maximum 40.2 17.5 6.0 Minimum 26.8 21.0 10.0 Mean 33.8 1.8 1.7 Std. Dev. 2.8 Regression 0.0004 0.025 Coefficient -0.001 0.026 0.022 Std. Error 0.020 t Value of Regression 1.15 Coefficient -0.057 -0.016
0.026 0.026 1.02
-0.0005' - 0 . 0 0 0 9 - 0 . 0 0 6 1 0.015 0.004 0.013 0.048 - 0 . 2 3 4
-0.487
0.020 - 0 . 0 9 6 0.025 0.052
-0.019 0.040
0.038 - 0 . 0 0 6 7 0.044 0.012
0.811 - 1 . 8 5
-0.490
0.845 - 0 . 5 7 6
i YT=Young Toms; YH=Young Hens; BH=Breeder Hens; BBB =Broad Breasted Bronze; LW=Large White.
ent ages and sex were sampled. Portions of the carcass showing small variability about the mean such as sternum length, femur length, and sternum depth would require less machine adjustment from bird to bird. Thus these physical entities are readily adaptable for use as reference standards or control guides. Regression coefficients of the formula Y = B 0 + BiX! + —Bn-iXn_! were calcu-
lated with the percent prime boneless meat as the dependent variable. Prime boneless meat included the breast, thigh and drumstick. Twenty-five weight and length variables were included in the regression analyses. The t values listed in Table 1 are to determine if the regression coefficient for each factor is significantly greater than zero. None of the physical measurement regression coefficients had a significant t value.
Downloaded from http://ps.oxfordjournals.org/ at University of Georgia on May 25, 2015
A (YT) BBBi 24 Mean Std. Dev.
395
PHYSICAL MEASUREMENTS OF TURKEYS TABLE 2.—Correlation coefficient matrix: yield interrelationships Total Wt. Breast Wt. .937 Percent Breast .825 Thigh W t . .720 Percent Thigh -.766 Prime Boneless M e a t .985 Percent Prime .665 Boneless Meat Drumstick W t . .910 Wings (3 joints) Wings (2 joints) Bone-Cage .904 Bone-Back .358 Bone-Femur .829 Tail .867
Breast Wt.
.921 .606 -.797 .965 .808 .828 .824 .255 .809 .832
Percent Breast
.349 -.884 .872 .855 .808 .456 .530 .790 .052 .779 .753
Thigh Wt.
-.161 .715 .458 .532 .536 .519 .352 .512
Percent Thigh
Prime Bone- Drum" less M e a t Wing 3 Wing 2 Back stick Joints Joints Cage Wt. Wt. Percent
Bone Back
Bone Femur
.089 .240
.824
-.742 -.514 -.856 -.275 .359 -.844 .067 -.883 -.789
.860 .350 .784 .834
.530 .433 .627 .511 .170 .450 .510
.923 .954 .150 .864 .829
.644 .624
.693 .813
.205 .851 .814
would be expected. The median circumference and the pubis to clavical distance were also highly correlated to other physical measurement variables. The correlation figures are in agreement with Berg (1953) that body weight was a good indicator of boneless meat yield, but the median circumference was superior to breast width or body depth as a major indicator to yield by weight. When percent prime meat was used to discount weight variance, all of the correlation coefficients were lower, but width at clavicals and median circumference had the highest correlation and would be better indicators of yield than those described by Berg (1953). The correlation figures presented by Draper et al. (1961) were lower than those presented here. Uniformity in the commercial birds may account for the higher figures in this
TABLE 3.—Correlation coefficient matrix: yield-physical measure relationships Pubis Sternum Width Width Breast to to Width Clavical Clavical Ilium Hip .867 Total Eviscerated Wt. Breast Wt. .795 Percent Breast .745 Thigh Wt. .534 Percent Thigh -.764 Prime Boneless M e a t .836 Percent Prime Boneless M e a t .522 Drumstick Wt. .882 Wings (3 joints) Wings (2 joints) Bone-Cage .881 Bone-Back .222 Bone-Femur .777 Tail .809
TransCirc.
Median Sternum Sternum Femur Circ. Length Depth Length
Tibia DrumLength stick Circ.
.827 .781 .742 .456 -.780 .798
.653 .571 .517 .474 -.480 .634
.912 .872 .808 .550 -.807 .893
688 578 468 633 - 402 666
.673 .661 .578 .441 — .565 .662
.935 .898 .822 .562 -.826 .911
.735 .653 .605 .493 -.633 .701
.555 .489 .483 .287 -.547 .522
.729 .657 .693 .405 -.737 .694
.771 .702 .712 .405 -.798 .721
.726 .636 .621 .431 -.631 .695
.497 .834 .328 .797 .838 .147 .833 .754
.419 .545
.592 .862
.467 .643
.592 .896
.562 .279 .521 .518
.870 .220 .849 .784
412 606 622 872 .642 .328 .487 .571
.642 .200 .525 .575
.893 .244 .881 .864
.409 .719 .495 .569 .759 .142 .692 .666
.270 .606 .117 .334 .586 .143 .493 .502
.450 .842 .566 -.117 .823 .124 .711 .671
.417 .910 .348 .023 .891 .108 .820 .701
.436 .768 .200 .667 .761 .220 .720 .679
Downloaded from http://ps.oxfordjournals.org/ at University of Georgia on May 25, 2015
Thus none of these physical measurements when used alone would be very dependable as a statistical formula indicator of prime meat yield. Values would have had to exceed 1.98 to show significance at the .05 level of probability. Tables 2, 3 and 4 present yield physical measurement interrelationships in the form of correlation coefficients. Several correlation coefficients exceeding 0.9 were noted in the yield interrelationships (Table 2). These include total weight associated with breast weight, prime boneless meat weight, drumstick weight and rib cage bone weight. Breast weight with percent breast and prime boneless meat; drumstick weight with wing weight and rib cage bone weight also were above 0.9. Generally high correlations existed regarding total weight and all of the dismemberment components as
.779 .867
396
P. G. STILES AND A. W. BRANT TABLE 4.—Correlation coefficient matrix: physical measurement interrelationships
Sternum to Ilium Breast Width Width at Clavical Width at Hip Transverse Circ. Median Circ. Sternum Length Sternum Depth Femur Length Tibia Length Drumstick Circ.
Pubis
Sternum
Clavical
Ilium
.731 .462 .821 .578 .592 .893 .729 .601 .756 .838 .676
.387 .835 .486 .531 .860 .710 .497 .728 .785 .697
Breast Width
.554 .596 .456 .487 .329 .294 .405 .385 .471
W h [f Clavical
Width at Hip
629 608 896 748 527 696 774 666
.472 .559 .525 .461 .544 .512 .483
SUMMARY Data providing a physical description and variability of turkeys used in three commercial further processing plants are presented. Physical measurements indicated to be of importance in equipment development were pubis to clavical distance, sternum to ilium distance, breast width, width at clavicals, back width, sternum length, femur length, and tibia length. Correlation coefficients are presented showing the interrelationships of each of these variables. Interrelationships of physical measurements to prime meat yield indicators are also given. The pubis to clavical measurements generally were highly correlated to nearly all the other physical measure variables. Percent thigh meat was negatively correlated to other yield variables. REFERENCES Asmundson, V. S., 1944. Measuring strain differences in the conformation of turkeys. Poultry Sci. 23: 21-29. Berg, R. W., 1953. Some relationship of several
Circ.
Median Circ.
.634 .462 .320 .539 .553 .453
.772 .583 .726 .818 .681
Sternum Sternum Length Depth
.464 .634 .678 .543
.466 .529 .317
Femur Length
.872 .662
Tibia Length
.668
body measurements to meat yield and reproductive performance in turkeys. Ph.D. Thesis, University of Minnesota, St. Paul, Minnesota. Draper, G. H., W. F. Krueger and J. H. Quisenberry, 1961. The relationship of dressing percentage to body measurements in turkeys. Poultry Sci. 40: 1396. Hartung, T. E., and G. W. Froning, 1968. Variation of physical components of turkey carcasses as influenced by sex, age and strain. Poultry Sci. 47: 1348-13 55. Jaap, R. G., 1938. Body conformation of the live market turkey. Poultry Sci. 17: 120-125. Jaap, R. G., and R. Penquite, 1938. Criteria of conformation in market poultry. Poultry Sci. 17: 425-430. Latimer, H. B., and J. A. Rosenbaum, 1926. A quantitive study of the anatomy of the turkey hen. Anatomical Record, 34: 15-23. Leighton, A. T., R. W. Berg and R. N. Shoffner, 1961. The importance of certain live body measurements for predicting meat yields in turkeys. Poultry Sci. 40: 1423. Maw, A. J. G., and W. A. Maw, 1939. The relation of body measurements to the fattening gains and the percentage of edible flesh in the fowl. Sci. Agric. 19: 589-596. Orr, H. L., E. C. Hunt and E. S. Snyder, 1956. Comparison of dressing percentages and yield of edible cooked meat in five strains of turkeys as broilers and as mature stock. Poultry Sci. 35: 333-338. Stiles, P. G., 1967. Physical parameters for further automation in poultry processing. Poultry Sci. 46: 651-654. Swickard, M. T., and A. M. Harkin, 1954. Percentage relationships of raw carcass weights and yield of cooked edible portion for young Beltsville Small White turkeys. Poultry Sci. 3 3 : 775-779.
Downloaded from http://ps.oxfordjournals.org/ at University of Georgia on May 25, 2015
study. Negative correlations for percent thigh in relation to several other variables was noted. More emphasis may be needed by breeders to increase thigh meat in comparison to other conformation variables. Since this meat is within the high value category, it appears to be an area which needs further genetic improvement to increase yields.
Trans-
ERNST, COLEMAN, KULENKAMP, RINGER AND PANGBORN
nix coturnix japonica) and embryogenesis of the domestic fowl. Ph.D. Thesis, Michigan State University, East Lansing, Michigan. Lucas, A. M., and C. Jamroz, 1961. Atlas of Avian Hematology. U. S. Dept. of Agriculture Monograph 25, Washington, D. C , 271 pp.
Nice, L. E., M. M. Nice and R. M. Kraft, 1935. Erythrocytes and hemoglobin in the blood of American birds. The Wilson Bulletin, 47: 120124. Sturkie, P. D., 1965. Avian Physiology, 2nd Ed. Cornell Univ. Press, Ithaca, N.Y.
Physical Measurement Interrelationships of Turkeys Used in Further Processing1
(Received for publication August 13, 1970)
T
URKEY carcass conformation may be expressed in terms of body weight, breast width, keel length, body depth, and other measurement standards. Geneticists have traditionally used these measurements as guides toward improving the market quality of breeding stock. Now with the advent of mechanized processing and deboning methods, measurement criteria must be reviewed and expressed in terms of their usefulness in developing automated processing machines and conveyorized deboning techniques. The objective of this study was to establish turkey physical measurement guidelines that would be useful to equipment manufacturers in their research and development. The interrelation of these physical measures are also presented. Latimer et al. (1926) present the general anatomical specifications and variability of the turkey hen. They found the percentage weights of the turkey viscera closely resembled the similar percentages in the chicken, but the musculature of the turkey was somewhat heavier. The skeleton weights 1
Research carried out under cooperative agreement between the University of California, Davis and the Transportation and Facilities Research Division, U.S. Department of Agriculture? 2 Current address: Division of Agriculture, Arizona State University, Tempe, Arizona 85281.
and the lengths of the long bones were less variable than many of the muscular parts of the body. Berg (1953) made a comprehensive analysis of deboned turkey meat yield and correlated meat yield to various body measurements. He noted that breast width measurement of live birds was highly correlated to meat yield. Body weight, breast width, and body depth were leading yield indicators. Body weight had the highest correlation coefficient to yield; but when body weight was held constant, body depth was the best indicator for predicting meat yield. Earlier work by Jaap and Penquite (1938) showed that the conformation of market poultry primarily determines its monetary value for human consumption. They stated that all linear measurements describing the conformation of dressed birds should be related to the body volume. The linear measurement compared to the cube root of body weight was a criterion of conformation. Another report by Jaap (1938) described a differential shape response of varieties to degrees of fleshing as noted in rib spread, anterior depth and shank length. Asmundson (1944) reported turkey breast width was correlated to body weight and strain. Sex and bird age affected the
Downloaded from http://ps.oxfordjournals.org/ at University of Georgia on May 25, 2015
P. G. STILES 2 AND A. W. BRANT University of California, Davis, California 95616
PHYSICAL MEASUREMENTS OF TURKEYS
EXPERIMENTAL
Physical measurements of eviscerated ready-to-cook carcasses and of deboned frames were taken in three separate commercial turkey processing plants. Carcasses were randomly selected from holding tanks. Fluid and ice were allowed to drain off prior to taking weights and measurements. A meter stick caliper and light-weight steel chain were used to take the following measurements: distance from pubis to clavical; width at the clavicals; distance from the ilium to the ventral point of the sternum; back width at the trochanter major of the femoral articulation; breast width at a depth of 2 cm. from the ventral point of the sternum; transverse circumference; median circumference omitting neck and tail; and maximum drumstick circumference. Eviscerated weight without neck and giblets was taken for each carcass and then the carcass was tagged and placed on the processing line for dismemberment. Each dismembered portion of the tagged carcass
was retrieved for further evaluation. Additional measurements included weight of each portion, femur length between distal points, sternum length including cartilage, sternum depth from the ventral process to a point where the frontal lateral portion of the sternum reaches a 30° angle to the median plane, and tibia length between distal points. Weights were accurate to within 1 gram, and distance over 10 cm. were accurate to within 1 cm. and those under 10 cm. within 0.1 cm. RESULTS AND DISCUSSION
Physical measurements descriptive of the bird's frame in relation to current deboning equipment and procedures are presented in Table 1. The groups represent the birds of the same sex, strain and class measured on the same day. They represent the variability among the common commercial stocks used for further processing. Maximum and minimum figures at the end of Table 1 are from the observed data only and do not necessarily represent the extremes that might be experienced if greater numbers of birds were studied. The data do indicate standards and tolerances that should be allowed in developing equipment and allowing for automated size adjustment. The means indicate the expected norm for each respective group. Tolerance allowances of four standard deviation units should be sufficient equipment adjustment variability for most automated equipment guides. Groups A and H represent one plant; B, C, D, F, J, K, and L a second plant; and E, G, and M a third plant. Groups A, B, C, D, E, and H were of the Broad Breasted Bronze variety while F, G, J, K, L, and M were Large Whites. The transverse circumference and the median circumference measurements exhibited the largest deviations about the mean. Other measurements did not vary to a great extent even though birds of differ-
Downloaded from http://ps.oxfordjournals.org/ at University of Georgia on May 25, 2015
physical measurements as shown by Swickard et al. (1954) and the fact that males have larger bones than females in proportion to their respective weights was found by Orr et al. (1956). Live body weight was cited by Leighton et al. (1961) as the most important single measurement for predicting meat yield in turkeys. Draper et al. (1961) reported body weight to be negatively correlated with dressing percentage while breast width was not correlated to dressing percentage but keel length was positively correlated to it. Hartung and Froning (1968) in a more recent study indicated edible meat yields of turkey carcasses are currently influenced by differences in sex, age, and strain. Physical measurements on chickens and their correlations to percent flesh were given by Maw et al. (1939) and the relation to automatic processing methods by Stiles (1967).
393
394
P. G. STILES AND A. W. BRANT TABLE 1.—Physical measurements of commercially deboned turkeys Pubis Sternum B Width Width t iJreast to Clavto at Clavof Width ical Ilium icals Back
Group
Transverse Circ.
Median Sternum Sternum Femur Tibia Circ. Length Depth Length Length
D
JH£gj£
CENTIMETERS 35.0 1.8
21.2 1.0
10.6 1.6
20.1 1.3
18.6 1.5
62.2 10.2
89.4 3.8
17.4 1.2
6.2 0.5
14.1 0.6
21.5 0.6
25.3 2.9
B (YT) BBB Mean Std. Dev.
IS 35.0 1.1
21.2 0.8
10.0 1.8
19.9 1.2
18.4 0.7
63.7 1.9
90.5 2.6
17.4 1.0
6.3 0.3
14.3 0.7
21.6 0.9
25.9 0.8
C (YT) BBB Mean Std. Dev.
20 35.0 1.8
22.0 1.0
10.8 1.3
21.0 0.9
18.0 2.7
63.0 3.2
93.6 3.4
17.6 0.6
6.2 0.4
13.8 0.6
21.5 0.6
25.5 2.5
D (YT) BBB Mean Std. Dev.
17 34.7 1.7
22.2 1.3
10.1 1.3
21.2 1.8
17.5 2.1
61.3 3.7
92.4 4.7
17.4 1.1
6.2 0.4
14.2 0.5
21.5 0.6
25.5 1.8
E (YH) BBB Mean Std. Dev.
17 29.0 0.7
18.0 0.6
8.3 1.1
16.2 0.7
15.4 0.9
51.5 1.4
77.4 1.5
15.2 0.8
5.4 0.4
11.8 0.5
18.0 0.5
20.2 0.7
F (YT) L W Mean Std. Dev.
26 34.5 1.3
22.1 0.9
11.0 1.0
21.6 1.4
17.5 1.0
63.2 3.2
92.8 3.2
18.2 0.7
6.1 0.4
14.3 0.6
21.3 0.7
27.1 0.1
G (BH) L W Mean Std. Dev.
27 30.2 1.4
19.5 1.1
10.3 1.1
17.8 0.8
16.2 1.0
56.8 2.8
83.8 3.1
15.7 1.0
5.9 0.4
12.2 1.6
18.2 0.6
24.1 1.2
H (YT) BBB Mean Std. Dev.
27 35.1 1.2
21.3 0.9
9.9 1.1
19.8 1.1
17.4 1.2
62.6 2.0
92.8 2.7
17.7 1.0
6.4 0.5
14.5 0.8
21.9 2.1
25.0 1.3
J
(YT) L W Mean Std. Dev.
22 35.2 1.5
22.4 1.0
9.4 1.2
21.6 1.1
17.0 0.8
62.5 1.9
93.1 2.3
18.4 0.8
68.4 0.4
14.6 0.5
21.6 0.8
26.5 1.4
K (BH) L W Mean Std. Dev.
22 30.6 0.6
19.4 1.0
8.9 1.2
17.5 1.0
16.0 1.0
54.6 2.8
81.7 3.3
15.7 0.6
5.7 0.3
12.0 0.4
17.7 0.5
24.1 1.1
L (YT) L W Mean Std. Dev.
20 34.2 2.9
22.5 1.0
9.3 1.5
21.4 1.1
16.9 1.0
63.6 2.8
93.3 2.3
18.2 0.7
6.6 0.5
14.5 0.6
21.8 0.9
27.1 1.4
M (YT) L W Mean Std. Dev.
10 32.8 1.8
22.6 0.8
8.7 1.3
19.1 1.2
16.2 1.4
61.9 3.1
89.3 4.9
17.6 1.6
7.1 0.4
14.6 0.6
22.0 0.9
26.0 2.0
24.8 14.8 19.8 2.1
21.5 14.2 17.7 2.1
70.7 49.5 60.5 7.1
102.0 75.0 88.8 6.6
20.5 14.4 17.1 1.3
7.7 4.7 6.1 0.1
16.3 10.9 13.7 1.1
24.1 16.7 20.9 1.5
29.6 19.3 24.5 2.9
Combined Groups 24.4 13.5 Maximum 40.2 17.5 6.0 Minimum 26.8 21.0 10.0 Mean 33.8 1.8 1.7 Std. Dev. 2.8 Regression 0.0004 0.025 Coefficient -0.001 0.026 0.022 Std. Error 0.020 t Value of Regression 1.15 Coefficient -0.057 -0.016
0.026 0.026 1.02
-0.0005' - 0 . 0 0 0 9 - 0 . 0 0 6 1 0.015 0.004 0.013 0.048 - 0 . 2 3 4
-0.487
0.020 - 0 . 0 9 6 0.025 0.052
-0.019 0.040
0.038 - 0 . 0 0 6 7 0.044 0.012
0.811 - 1 . 8 5
-0.490
0.845 - 0 . 5 7 6
i YT=Young Toms; YH=Young Hens; BH=Breeder Hens; BBB =Broad Breasted Bronze; LW=Large White.
ent ages and sex were sampled. Portions of the carcass showing small variability about the mean such as sternum length, femur length, and sternum depth would require less machine adjustment from bird to bird. Thus these physical entities are readily adaptable for use as reference standards or control guides. Regression coefficients of the formula Y = B 0 + BiX! + —Bn-iXn_! were calcu-
lated with the percent prime boneless meat as the dependent variable. Prime boneless meat included the breast, thigh and drumstick. Twenty-five weight and length variables were included in the regression analyses. The t values listed in Table 1 are to determine if the regression coefficient for each factor is significantly greater than zero. None of the physical measurement regression coefficients had a significant t value.
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A (YT) BBBi 24 Mean Std. Dev.
395
PHYSICAL MEASUREMENTS OF TURKEYS TABLE 2.—Correlation coefficient matrix: yield interrelationships Total Wt. Breast Wt. .937 Percent Breast .825 Thigh W t . .720 Percent Thigh -.766 Prime Boneless M e a t .985 Percent Prime .665 Boneless Meat Drumstick W t . .910 Wings (3 joints) Wings (2 joints) Bone-Cage .904 Bone-Back .358 Bone-Femur .829 Tail .867
Breast Wt.
.921 .606 -.797 .965 .808 .828 .824 .255 .809 .832
Percent Breast
.349 -.884 .872 .855 .808 .456 .530 .790 .052 .779 .753
Thigh Wt.
-.161 .715 .458 .532 .536 .519 .352 .512
Percent Thigh
Prime Bone- Drum" less M e a t Wing 3 Wing 2 Back stick Joints Joints Cage Wt. Wt. Percent
Bone Back
Bone Femur
.089 .240
.824
-.742 -.514 -.856 -.275 .359 -.844 .067 -.883 -.789
.860 .350 .784 .834
.530 .433 .627 .511 .170 .450 .510
.923 .954 .150 .864 .829
.644 .624
.693 .813
.205 .851 .814
would be expected. The median circumference and the pubis to clavical distance were also highly correlated to other physical measurement variables. The correlation figures are in agreement with Berg (1953) that body weight was a good indicator of boneless meat yield, but the median circumference was superior to breast width or body depth as a major indicator to yield by weight. When percent prime meat was used to discount weight variance, all of the correlation coefficients were lower, but width at clavicals and median circumference had the highest correlation and would be better indicators of yield than those described by Berg (1953). The correlation figures presented by Draper et al. (1961) were lower than those presented here. Uniformity in the commercial birds may account for the higher figures in this
TABLE 3.—Correlation coefficient matrix: yield-physical measure relationships Pubis Sternum Width Width Breast to to Width Clavical Clavical Ilium Hip .867 Total Eviscerated Wt. Breast Wt. .795 Percent Breast .745 Thigh Wt. .534 Percent Thigh -.764 Prime Boneless M e a t .836 Percent Prime Boneless M e a t .522 Drumstick Wt. .882 Wings (3 joints) Wings (2 joints) Bone-Cage .881 Bone-Back .222 Bone-Femur .777 Tail .809
TransCirc.
Median Sternum Sternum Femur Circ. Length Depth Length
Tibia DrumLength stick Circ.
.827 .781 .742 .456 -.780 .798
.653 .571 .517 .474 -.480 .634
.912 .872 .808 .550 -.807 .893
688 578 468 633 - 402 666
.673 .661 .578 .441 — .565 .662
.935 .898 .822 .562 -.826 .911
.735 .653 .605 .493 -.633 .701
.555 .489 .483 .287 -.547 .522
.729 .657 .693 .405 -.737 .694
.771 .702 .712 .405 -.798 .721
.726 .636 .621 .431 -.631 .695
.497 .834 .328 .797 .838 .147 .833 .754
.419 .545
.592 .862
.467 .643
.592 .896
.562 .279 .521 .518
.870 .220 .849 .784
412 606 622 872 .642 .328 .487 .571
.642 .200 .525 .575
.893 .244 .881 .864
.409 .719 .495 .569 .759 .142 .692 .666
.270 .606 .117 .334 .586 .143 .493 .502
.450 .842 .566 -.117 .823 .124 .711 .671
.417 .910 .348 .023 .891 .108 .820 .701
.436 .768 .200 .667 .761 .220 .720 .679
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Thus none of these physical measurements when used alone would be very dependable as a statistical formula indicator of prime meat yield. Values would have had to exceed 1.98 to show significance at the .05 level of probability. Tables 2, 3 and 4 present yield physical measurement interrelationships in the form of correlation coefficients. Several correlation coefficients exceeding 0.9 were noted in the yield interrelationships (Table 2). These include total weight associated with breast weight, prime boneless meat weight, drumstick weight and rib cage bone weight. Breast weight with percent breast and prime boneless meat; drumstick weight with wing weight and rib cage bone weight also were above 0.9. Generally high correlations existed regarding total weight and all of the dismemberment components as
.779 .867
396
P. G. STILES AND A. W. BRANT TABLE 4.—Correlation coefficient matrix: physical measurement interrelationships
Sternum to Ilium Breast Width Width at Clavical Width at Hip Transverse Circ. Median Circ. Sternum Length Sternum Depth Femur Length Tibia Length Drumstick Circ.
Pubis
Sternum
Clavical
Ilium
.731 .462 .821 .578 .592 .893 .729 .601 .756 .838 .676
.387 .835 .486 .531 .860 .710 .497 .728 .785 .697
Breast Width
.554 .596 .456 .487 .329 .294 .405 .385 .471
W h [f Clavical
Width at Hip
629 608 896 748 527 696 774 666
.472 .559 .525 .461 .544 .512 .483
SUMMARY Data providing a physical description and variability of turkeys used in three commercial further processing plants are presented. Physical measurements indicated to be of importance in equipment development were pubis to clavical distance, sternum to ilium distance, breast width, width at clavicals, back width, sternum length, femur length, and tibia length. Correlation coefficients are presented showing the interrelationships of each of these variables. Interrelationships of physical measurements to prime meat yield indicators are also given. The pubis to clavical measurements generally were highly correlated to nearly all the other physical measure variables. Percent thigh meat was negatively correlated to other yield variables. REFERENCES Asmundson, V. S., 1944. Measuring strain differences in the conformation of turkeys. Poultry Sci. 23: 21-29. Berg, R. W., 1953. Some relationship of several
Circ.
Median Circ.
.634 .462 .320 .539 .553 .453
.772 .583 .726 .818 .681
Sternum Sternum Length Depth
.464 .634 .678 .543
.466 .529 .317
Femur Length
.872 .662
Tibia Length
.668
body measurements to meat yield and reproductive performance in turkeys. Ph.D. Thesis, University of Minnesota, St. Paul, Minnesota. Draper, G. H., W. F. Krueger and J. H. Quisenberry, 1961. The relationship of dressing percentage to body measurements in turkeys. Poultry Sci. 40: 1396. Hartung, T. E., and G. W. Froning, 1968. Variation of physical components of turkey carcasses as influenced by sex, age and strain. Poultry Sci. 47: 1348-13 55. Jaap, R. G., 1938. Body conformation of the live market turkey. Poultry Sci. 17: 120-125. Jaap, R. G., and R. Penquite, 1938. Criteria of conformation in market poultry. Poultry Sci. 17: 425-430. Latimer, H. B., and J. A. Rosenbaum, 1926. A quantitive study of the anatomy of the turkey hen. Anatomical Record, 34: 15-23. Leighton, A. T., R. W. Berg and R. N. Shoffner, 1961. The importance of certain live body measurements for predicting meat yields in turkeys. Poultry Sci. 40: 1423. Maw, A. J. G., and W. A. Maw, 1939. The relation of body measurements to the fattening gains and the percentage of edible flesh in the fowl. Sci. Agric. 19: 589-596. Orr, H. L., E. C. Hunt and E. S. Snyder, 1956. Comparison of dressing percentages and yield of edible cooked meat in five strains of turkeys as broilers and as mature stock. Poultry Sci. 35: 333-338. Stiles, P. G., 1967. Physical parameters for further automation in poultry processing. Poultry Sci. 46: 651-654. Swickard, M. T., and A. M. Harkin, 1954. Percentage relationships of raw carcass weights and yield of cooked edible portion for young Beltsville Small White turkeys. Poultry Sci. 3 3 : 775-779.
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study. Negative correlations for percent thigh in relation to several other variables was noted. More emphasis may be needed by breeders to increase thigh meat in comparison to other conformation variables. Since this meat is within the high value category, it appears to be an area which needs further genetic improvement to increase yields.
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