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Relationship Between Fat in Breast and Thigh Muscles and Skin with Abdominal Fat from Mated and Unmated Female Coturnix Quail1
Relationship Between Fat in Breast and Thigh Muscles and Skin with Abdominal Fat from Mated and Unmated Female Coturnix Quail1 MORTEZA SADJADI 2 ' 3 and WALTER A. BECKER Department of Animal Sciences, Washington State University, Pullman, Washington 99164
(Received for publication December 31, 1979)
1980 Poultry Science 59:2462-2466 INTRODUCTION Coturnix quail can serve as a pilot animal to study t h e problem of excess abdominal fat found in chicken broilers. Sadjadi and Becker ( 1 9 8 0 ) d e t e r m i n e d t h a t the heritability of leaf and abdominal fat in Coturnix quail is high, t h e genetic correlation between abdominal fat and live body weight is m o d e r a t e , and t h a t males have a much higher percentage of fat c o n t e n t t h a n females, t h e reverse of findings in chickens. A surgical procedure was developed that enabled t h e m t o estimate leaf fat in live birds. Dawson et al. ( 1 9 7 1 ) , with Bobwhite quail, reported that percentage meat fat of males and females is similar and n o t affected by t h e age of quail. Fat is 3% and moisture 74% of the raw meat. Singh and Essary ( 1 9 7 4 ) found t h a t percentage thigh fat is about three and a half times t h a t of breast fat in chickens at 8 weeks of age.
1 Scientific Paper No. 5542. Project 0343. College of Agriculture Research Center, Washington State University, Pullman, WA. 2 Present address: Department of Poultry Science, Oregon State University, Corvallis, OR 973 31. 3 Part of a thesis submitted as partial fulfillment of the requirements for the master of Science degree.
T h e percent moisture in breast muscle is 74.7% (males) and 73.9% (females) and in thigh muscle 7 2 . 8 % (males) and 7 3 . 3 % (females). Percentage fat in t h e breast muscle is 2% (males) and 3.5% (females) and in t h e thigh muscle 7.9% (males) and 9 . 3 % (females). They also found t h a t neither age nor sex has any significant effect on percentage fat in thigh and breast muscle of chickens. Mickelberry et al. ( 1 9 6 6 ) , working with chickens, reported t h e a m o u n t of fat in t h e diet did n o t have a significant effect on t h e fat in breast muscle b u t that it did affect t h e fat in thigh muscle. Salmon and O'Neil ( 1 9 7 3 ) reported t h a t fatty acid composition of t h e thigh and breast in t u r k e y s is related t o age and dietary fat. This s t u d y was c o n d u c t e d to d e t e r m i n e t h e relationships between abdominal fat and t h e fat and moisture in the breast muscle and skin; fat and m o i s t u r e in the thigh skin; and fat in the thigh muscle of mated and u n m a t e d female Coturnix quail. These relationships provide information valuable to those researchers w h o use Coturnix quail as a pilot animal for studying t h e b o d y composition of chickens. MATERIALS AND METHODS Coturnix quail eggs were collected from a r a n d o m b r e d population maintained at t h e
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ABSTRACT Coturnix quail chicks were hatched from randomly selected eggs and grown to adulthood. Forty-two mated and 13 unmated females were killed at 107 days of age. Correlations between abdominal, fat and fat measured at different locations (breast, thigh, crop collar) were high. Percentage thigh fat was 1.3 times that of breast fat. There was no difference (P>.05) between mated and unmated female quail for percentage fat and moisture content of breast muscle and skin and percentage fat content of thigh muscle. A highly significant difference was found for percentage fat and percentage moisture content of wet thigh skin between mated and unmated birds. The phenotypic correlation between percentage moisture and fat content in the breast muscle was —.76 and was —.94 in the breast skin in both mated and unmated females. Coturnix quail may be used as a pilot animal in body composition research provided due caution is taken because of the difference between species. (Key words: fat, moisture, breast, thigh, skin, muscle, Coturnix quail, mated, unmated)
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TABLE 1. Means, standard deviations, minimum and maximum values, and coefficients of variation in 107-day-old, mated (N = 42) and unmated (N = 13) female Coturnix quail Trait Live body weight (g) Mated Unmated Leaf fat weight (g) Mated Unmated Gizzard fat weight (g) Mated Unmated Abdominal fat weight (g) Mated Unmated % Abdominal fat/live weight Mated Unmated
Mean a
SD
Minimum
Maximum
CV%
161 160
16.13 15.06
136 136
197 180
10 9
4.81 4.46
2.67 2.31
1.68 .60
11.28 8.65
56 52
.47 .48
.24 .28
.17 .13
1.08 1.08
52 58
5.28 4.93
2.87 2.56
1.95
11.85 9.48
54 52
3.18 3.04
1.51 1.50
1.36
6.29 5.53
48 50
.73
.47
None of the differences between mated and unmated birds were significantly different at 5% level.
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The remains of carcass were placed in a copolymer bag and frozen at —26.1 C for subsequent dissection. Whole thighs and breast were later removed according to the procedure described by Dam et al. (1970). Breast and thigh skins were removed, weighed, tagged, frozen at —26.1 C, and saved for fat and moisture determination. Breast and thigh meat were placed in 21 x 20 cm polyethylene lined cellophane bags, vacuum sealed, and frozen at - 2 6 . 1 C. To determine fat and moisture content, breast meat was thawed, cut into pieces, and ground with a Sorvall omni mixer. Thigh meat was ground with mortar and pestle because of the small amount of meat. Fat was extracted from 3 g duplicate samples of ground breast and thigh from each bird, using the Goldfisch ether extraction method according to the AOAC (1975) procedure 24.005(a), with the exception that samples were dried for 16 to 17 hr. Moisture of breast and thigh skins was calculated by difference after freeze drying for 92 hr. Aluminum weighing dishes were used to recover rendered fat during freeze drying. After weighing the skins, they were placed in evacuated copolymer bags and held at —26.1 C for fat extraction. Fat was extracted from the skin according to the procedure used for back skins by Moran et al. (1968). Moisture determinations were obtained using duplicate samples of the ground breast meat. Samples were weighed
Washington State University Poultry Farm and hatched. The chicks were brooded on the floor under heat lamps until they were 35 days of age, at which time each bird was sexed, wing banded, and placed in a 10 by 16 cm cage. The feed contained 3040 kcal/kg and 21% protein. Feed and water were available ad libitum. Forty-two females were single pair mated at 67 days of age. Thirteen unmated females were raised under the same environmental conditions (Sadjadi and Becker, 1980). Each female quail was weighed and slaughtered at 107 days after 24 hr starvation (water was available). Birds were scalded, feathers removed, and then shanks and heads removed. They were then placed in 22.9 X 45.7 cm polyvinylidenevinyl chloride copolymer bags and frozen at — 18.7 C for subsequent dissection. After thawing for 24 hr at 1.65 C, the carcasses were dissected. The neck with skin was removed. The abdomen was opened at the posterior end of the stern-um and an incision made anteriorly between the vertebral and sternal ribs. Leaf fat (layer of fat lying over the intestines, extending to the ischium and surrounding the cloaca) and gizzard fat (fat surrounding the gizzard and ending between the gizzard and proventriculus and attachment of duodenum) were separately removed and weighed. Fat deposits lying on the posterior end of the breast muscle and on the crop collar were removed, combined, and weighed.
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TABLE 2. Means and standard deviations for fat and moisture in breast from female Cotumix quail Unmated
Mated a
Mean
Ground breast meat weight (g) % Fat (wet basis) % Fat (dry basis) % Moisture Breast skin weight (g) % Fat (wet basis) % Fat (dry basis) % Moisture
25.05 4.25 13.24 68.28 3.28 51.00 80.99 37.29
SD
Mean
2.48 1.69 4.43 1.68
25.71 4.28 13.56 68.92 3.27 48.72 79.18 39.05
.63
7.08 4.04 5.77
SD
5.56 1.91 5.18 1.91 .80
8.85 7.32 6.88
None of the differences between mated and unmated birds were significantly different at 5% level.
and dried for 16 t o 17 hr in an oven at 100 C and weighed. Due to the small size of sample available from ground thigh m e a t , moisture d e t e r m i n a t i o n s were n o t o b t a i n e d . Data were analyzed using standard statistical m e t h o d s to estimate t h e correlations b e t w e e n fat at different locations and their relationship with abdominal fat. RESULTS AND DISCUSSION Means, standard deviations, m i n i m u m and m a x i m u m values, and coefficients of variation of b o d y weight and abdominal fat are given in Table 1. The coefficient of variation (CV) of a b d o m i n a l fat was 5.4 times greater t h a n that of b o d y weight in m a t e d birds and 5.8 times greater in u n m a t e d birds. There were no significant differences b e t w e e n t h e m a t e d and unm a t e d birds for any of these traits. Abdominal fat included b o t h leaf fat and gizzard fat weights. Leaf fat was 9 1 % and gizzard fat 9% of
t h e total abdominal fat. Table 2 shows values of fat and moisture in breast muscle. The percentage of fat in g r o u n d breast muscle on a wet basis was 4 . 3 % and o n a dry basis 13%. This is similar to t h e 3.5% figure reported b y Singh and Essary ( 1 9 7 4 ) for chicken breast fat. The moisture c o n t e n t of quail muscle was 68%, which was lower t h a n t h e 73.9% reported for chickens by Singh and Essary ( 1 9 7 4 ) . The fat in quail breast skin was 4 9 % (wet basis) and 80% (dry basis), while t h e moisture c o n t e n t was 38%. No significant differences between m a t e d and u n m a t e d birds were observed for breast meat weight, percentage fat, and moisture :n the breast muscle and skin. Means and standard deviations of thigh fat and moisture are presented in Table 3. There was no significant difference in percentage fat in thigh muscle b e t w e e n mated and u n m a t e d birds. Percentage fat in thigh muscle was 5.5%, which is less t h a n t h e 9.3% found in female
TABLE 3. Means and standard deviations of thigh fat and moisture in female Cotumix quail Mated Trait
Mean
Ground thigh meat weight (g) % Fat (wet basis) Thigh skin weight (g) % Fat (wet basis) % Fat (dry basis) % Moisture
8.64* 5.54 1.20** 44.06** 74.76** 41.67**
*P<.05. **P<.01.
Unmated SD .90
1.20 .24
9.30 6.75 7.43
Mean 8.10* 5.44 1.03** 54.06** 80.64** 33.89**
SD
1.03 1.07 .24
12.26 8.68 9.52
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Trait
a
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C O T U R N I X BODY COMPOSITION
T A B L E 4 . Means and standard deviations in female Cotumix
of fat at different quail
locations
Mated Mean3
Trait
Meana
SD
4.28 1.21
1.97 .47
4.08 1.09
2.14 .52
2.60 .74
1.00 .23
2.50 .67
1.20 .31
16.79
6.72
15.41
6.97
13.85
4.75
13.10
5.70
None of t h e differences b e t w e e n m a t e d and u n m a t e d birds were significantly different at 5% level. Fat deposited from left and right anterior edge sartorius muscle was c o m b i n e d and weighed.
chickens (Singh and Essary, 1974). Thigh meat (deboned) weight was significantly greater (P<.05) in mated than unmated birds (8.64 vs 8.10 g). If mated birds were more active than unmated ones, this could account for greater muscle development and greater weight. There were significant differences between the mated and unmated birds for thigh skin weight (P<.01) and percentage fat and moisture content in thigh skin (P<.01). Mated birds had a higher thigh skin weight, a lower percentage fat in the thigh skin, and greater percentage moisture than unmated birds. These differences could be accounted for by the size of the thighs. Percentage fat in the thigh was about 1.3 times that in the breast, which was less than the 3.5 times reported by Singh and Essary (1974) for chickens. Percentage fat in the breast skin was higher on a wet basis than in the thigh skin in mated birds. In unmated birds the percentage fat in the breast skin was lower than fat in the thigh skin. Fat content in the crop collar plus fat at the edge of breast muscle was 2.6% of live weight, and depot fat attached to the sartorius muscle was .7%. No difference (P<.05) was found between mated and unmated birds for either fat in the crop collar plus fat at the edge of breast muscle or sartorius fat (Table 4). Correlation coefficients between abdominal fat and fat in different locations are given in Table 5. The correlations were all statistically different from zero (P<.01). There was a positive relationship between abdominal fat
percentage and percentage fat of breast muscle, percentage fat of breast skin, percentage fat of thigh muscle, and percentage fat of thigh skin. The relationship between percentage fat and percentage moisture content was determined in the breast muscle and breast skin (Table 6). The correlation coefficients were highly negative (—.76, —.99). There was no significant difference in the correlations between the mated and unmated birds. These results indicate that selection against abdominal fat would probably reduce fat at other locations because of the high correlations
T A B L E 5. Correlation coefficients between percentage abdominal fat and percentage fat at other locations Fat location % Crop collar plus fat at t h e edge of breast muscle, live weight % Sartorius muscle d e p o t fat, a live weight % Crop collar fat plus fat at t h e edge of breast muscle, breast muscle weight % Sartorius muscle d e p o t fat, thigh muscle weight % Fat of wet sample of breast muscle % Fat of dry sample breast muscle % Fat in wet breast skin % Fat in dried breast skin % Fat in wet sample of thigh muscle % Fat in wet thigh skins % Fat in dried thigh skins
r
.79 .79 .72 .77 .65 .67 .74 .72 .57 .71 .73
a F a t deposits from left and right sartorius muscles were c o m b i n e d and weighed.
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Crop collar fat plus fat at posterior edge of breast muscle weight (g) Sartorius muscle d e p o t f a t b weight (g) % Crop collar fat plus fat at the edge of breast muscle, live weight % Sartorius muscle d e p o t fat, live weight % Crop collar fat plus fat at t h e edge of breast muscle, breast muscle weight % Sartorius muscle d e p o t fat, thigh muscle weight
Unmated SD
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TABLE 6. Correlation coefficients between fat and moisture weights in female Coturnix quail breast muscle and skin Location
r
Breast muscle Breast skin
-.76 -.99
ACKNOWLEDGMENTS The authors are indebted to Larry Mirosh for technical assistance. The senior author was supported, in part, by a scholarship from Ferdowsi University, Mashhad, Iran.
REFERENCES Association of Official Agricultural Chemists, 1975.
Downloaded from http://ps.oxfordjournals.org/ at Florida International University on June 4, 2015
and that Coturnix quail may be used as a pilot animal in body composition research provided due caution is taken because of the differences between species.
Official methods of analysis. 12th ed. AOAC, Washington, DC. Dam, R., G. W. Froning, and J. H. Skala, 1970. Recommended methods for the analysis of eggs and poultry meat. North Central Regional Research Publ. No. 205. Dawson, L. E., L. R. York, N. Amon, C. Kulenkamp, and T. H. Coleman, 1971. Composition and acceptability of meat from Bobwhite quail. Poultry Sci. 50:1805-1810. Moran, E. T., Jr., J. D. Summers, and H. L. Orr, 1968. Backfat, quantitative measurement of broiler carcass finish: Technique, correlation with grade and effect of dietary caloric density. Food Technol. 22:999-1002. Mickelberry, W. C , J. C. Rogler, and W. J. Stadelman, 1966. The influence of dietary fat and environmental temperature upon chick growth and carcass composition. Poultry Sci. 45:313—321. Sadjadi, M., and W. A. Becker, 1980. Heritability and genetic correlation of body weight and surgically removed abdominal fat in Coturnix quail. Poultry Sci. 59:1977-1984. Salmon, R. E„ and J. B. O'Neil, 1973. The effect of the level and source and of a change source of dietary fat on the fatty acid composition of the depot fat and the thigh and breast meat of turkeys as related to age. Poultry Sci. 52:302— 314. Singh, S. P., and E. O. Essary, 1974. Factors influencing dressing percentage and tissue composition of broilers. Poultry Sci. 53:2143-2147.
(Received for publication December 31, 1979)
1980 Poultry Science 59:2462-2466 INTRODUCTION Coturnix quail can serve as a pilot animal to study t h e problem of excess abdominal fat found in chicken broilers. Sadjadi and Becker ( 1 9 8 0 ) d e t e r m i n e d t h a t the heritability of leaf and abdominal fat in Coturnix quail is high, t h e genetic correlation between abdominal fat and live body weight is m o d e r a t e , and t h a t males have a much higher percentage of fat c o n t e n t t h a n females, t h e reverse of findings in chickens. A surgical procedure was developed that enabled t h e m t o estimate leaf fat in live birds. Dawson et al. ( 1 9 7 1 ) , with Bobwhite quail, reported that percentage meat fat of males and females is similar and n o t affected by t h e age of quail. Fat is 3% and moisture 74% of the raw meat. Singh and Essary ( 1 9 7 4 ) found t h a t percentage thigh fat is about three and a half times t h a t of breast fat in chickens at 8 weeks of age.
1 Scientific Paper No. 5542. Project 0343. College of Agriculture Research Center, Washington State University, Pullman, WA. 2 Present address: Department of Poultry Science, Oregon State University, Corvallis, OR 973 31. 3 Part of a thesis submitted as partial fulfillment of the requirements for the master of Science degree.
T h e percent moisture in breast muscle is 74.7% (males) and 73.9% (females) and in thigh muscle 7 2 . 8 % (males) and 7 3 . 3 % (females). Percentage fat in t h e breast muscle is 2% (males) and 3.5% (females) and in t h e thigh muscle 7.9% (males) and 9 . 3 % (females). They also found t h a t neither age nor sex has any significant effect on percentage fat in thigh and breast muscle of chickens. Mickelberry et al. ( 1 9 6 6 ) , working with chickens, reported t h e a m o u n t of fat in t h e diet did n o t have a significant effect on t h e fat in breast muscle b u t that it did affect t h e fat in thigh muscle. Salmon and O'Neil ( 1 9 7 3 ) reported t h a t fatty acid composition of t h e thigh and breast in t u r k e y s is related t o age and dietary fat. This s t u d y was c o n d u c t e d to d e t e r m i n e t h e relationships between abdominal fat and t h e fat and moisture in the breast muscle and skin; fat and m o i s t u r e in the thigh skin; and fat in the thigh muscle of mated and u n m a t e d female Coturnix quail. These relationships provide information valuable to those researchers w h o use Coturnix quail as a pilot animal for studying t h e b o d y composition of chickens. MATERIALS AND METHODS Coturnix quail eggs were collected from a r a n d o m b r e d population maintained at t h e
2462
Downloaded from http://ps.oxfordjournals.org/ at Florida International University on June 4, 2015
ABSTRACT Coturnix quail chicks were hatched from randomly selected eggs and grown to adulthood. Forty-two mated and 13 unmated females were killed at 107 days of age. Correlations between abdominal, fat and fat measured at different locations (breast, thigh, crop collar) were high. Percentage thigh fat was 1.3 times that of breast fat. There was no difference (P>.05) between mated and unmated female quail for percentage fat and moisture content of breast muscle and skin and percentage fat content of thigh muscle. A highly significant difference was found for percentage fat and percentage moisture content of wet thigh skin between mated and unmated birds. The phenotypic correlation between percentage moisture and fat content in the breast muscle was —.76 and was —.94 in the breast skin in both mated and unmated females. Coturnix quail may be used as a pilot animal in body composition research provided due caution is taken because of the difference between species. (Key words: fat, moisture, breast, thigh, skin, muscle, Coturnix quail, mated, unmated)
COTURNIX BODY COMPOSITION
2463
TABLE 1. Means, standard deviations, minimum and maximum values, and coefficients of variation in 107-day-old, mated (N = 42) and unmated (N = 13) female Coturnix quail Trait Live body weight (g) Mated Unmated Leaf fat weight (g) Mated Unmated Gizzard fat weight (g) Mated Unmated Abdominal fat weight (g) Mated Unmated % Abdominal fat/live weight Mated Unmated
Mean a
SD
Minimum
Maximum
CV%
161 160
16.13 15.06
136 136
197 180
10 9
4.81 4.46
2.67 2.31
1.68 .60
11.28 8.65
56 52
.47 .48
.24 .28
.17 .13
1.08 1.08
52 58
5.28 4.93
2.87 2.56
1.95
11.85 9.48
54 52
3.18 3.04
1.51 1.50
1.36
6.29 5.53
48 50
.73
.47
None of the differences between mated and unmated birds were significantly different at 5% level.
Downloaded from http://ps.oxfordjournals.org/ at Florida International University on June 4, 2015
The remains of carcass were placed in a copolymer bag and frozen at —26.1 C for subsequent dissection. Whole thighs and breast were later removed according to the procedure described by Dam et al. (1970). Breast and thigh skins were removed, weighed, tagged, frozen at —26.1 C, and saved for fat and moisture determination. Breast and thigh meat were placed in 21 x 20 cm polyethylene lined cellophane bags, vacuum sealed, and frozen at - 2 6 . 1 C. To determine fat and moisture content, breast meat was thawed, cut into pieces, and ground with a Sorvall omni mixer. Thigh meat was ground with mortar and pestle because of the small amount of meat. Fat was extracted from 3 g duplicate samples of ground breast and thigh from each bird, using the Goldfisch ether extraction method according to the AOAC (1975) procedure 24.005(a), with the exception that samples were dried for 16 to 17 hr. Moisture of breast and thigh skins was calculated by difference after freeze drying for 92 hr. Aluminum weighing dishes were used to recover rendered fat during freeze drying. After weighing the skins, they were placed in evacuated copolymer bags and held at —26.1 C for fat extraction. Fat was extracted from the skin according to the procedure used for back skins by Moran et al. (1968). Moisture determinations were obtained using duplicate samples of the ground breast meat. Samples were weighed
Washington State University Poultry Farm and hatched. The chicks were brooded on the floor under heat lamps until they were 35 days of age, at which time each bird was sexed, wing banded, and placed in a 10 by 16 cm cage. The feed contained 3040 kcal/kg and 21% protein. Feed and water were available ad libitum. Forty-two females were single pair mated at 67 days of age. Thirteen unmated females were raised under the same environmental conditions (Sadjadi and Becker, 1980). Each female quail was weighed and slaughtered at 107 days after 24 hr starvation (water was available). Birds were scalded, feathers removed, and then shanks and heads removed. They were then placed in 22.9 X 45.7 cm polyvinylidenevinyl chloride copolymer bags and frozen at — 18.7 C for subsequent dissection. After thawing for 24 hr at 1.65 C, the carcasses were dissected. The neck with skin was removed. The abdomen was opened at the posterior end of the stern-um and an incision made anteriorly between the vertebral and sternal ribs. Leaf fat (layer of fat lying over the intestines, extending to the ischium and surrounding the cloaca) and gizzard fat (fat surrounding the gizzard and ending between the gizzard and proventriculus and attachment of duodenum) were separately removed and weighed. Fat deposits lying on the posterior end of the breast muscle and on the crop collar were removed, combined, and weighed.
SADJADI AND BECKER
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TABLE 2. Means and standard deviations for fat and moisture in breast from female Cotumix quail Unmated
Mated a
Mean
Ground breast meat weight (g) % Fat (wet basis) % Fat (dry basis) % Moisture Breast skin weight (g) % Fat (wet basis) % Fat (dry basis) % Moisture
25.05 4.25 13.24 68.28 3.28 51.00 80.99 37.29
SD
Mean
2.48 1.69 4.43 1.68
25.71 4.28 13.56 68.92 3.27 48.72 79.18 39.05
.63
7.08 4.04 5.77
SD
5.56 1.91 5.18 1.91 .80
8.85 7.32 6.88
None of the differences between mated and unmated birds were significantly different at 5% level.
and dried for 16 t o 17 hr in an oven at 100 C and weighed. Due to the small size of sample available from ground thigh m e a t , moisture d e t e r m i n a t i o n s were n o t o b t a i n e d . Data were analyzed using standard statistical m e t h o d s to estimate t h e correlations b e t w e e n fat at different locations and their relationship with abdominal fat. RESULTS AND DISCUSSION Means, standard deviations, m i n i m u m and m a x i m u m values, and coefficients of variation of b o d y weight and abdominal fat are given in Table 1. The coefficient of variation (CV) of a b d o m i n a l fat was 5.4 times greater t h a n that of b o d y weight in m a t e d birds and 5.8 times greater in u n m a t e d birds. There were no significant differences b e t w e e n t h e m a t e d and unm a t e d birds for any of these traits. Abdominal fat included b o t h leaf fat and gizzard fat weights. Leaf fat was 9 1 % and gizzard fat 9% of
t h e total abdominal fat. Table 2 shows values of fat and moisture in breast muscle. The percentage of fat in g r o u n d breast muscle on a wet basis was 4 . 3 % and o n a dry basis 13%. This is similar to t h e 3.5% figure reported b y Singh and Essary ( 1 9 7 4 ) for chicken breast fat. The moisture c o n t e n t of quail muscle was 68%, which was lower t h a n t h e 73.9% reported for chickens by Singh and Essary ( 1 9 7 4 ) . The fat in quail breast skin was 4 9 % (wet basis) and 80% (dry basis), while t h e moisture c o n t e n t was 38%. No significant differences between m a t e d and u n m a t e d birds were observed for breast meat weight, percentage fat, and moisture :n the breast muscle and skin. Means and standard deviations of thigh fat and moisture are presented in Table 3. There was no significant difference in percentage fat in thigh muscle b e t w e e n mated and u n m a t e d birds. Percentage fat in thigh muscle was 5.5%, which is less t h a n t h e 9.3% found in female
TABLE 3. Means and standard deviations of thigh fat and moisture in female Cotumix quail Mated Trait
Mean
Ground thigh meat weight (g) % Fat (wet basis) Thigh skin weight (g) % Fat (wet basis) % Fat (dry basis) % Moisture
8.64* 5.54 1.20** 44.06** 74.76** 41.67**
*P<.05. **P<.01.
Unmated SD .90
1.20 .24
9.30 6.75 7.43
Mean 8.10* 5.44 1.03** 54.06** 80.64** 33.89**
SD
1.03 1.07 .24
12.26 8.68 9.52
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Trait
a
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C O T U R N I X BODY COMPOSITION
T A B L E 4 . Means and standard deviations in female Cotumix
of fat at different quail
locations
Mated Mean3
Trait
Meana
SD
4.28 1.21
1.97 .47
4.08 1.09
2.14 .52
2.60 .74
1.00 .23
2.50 .67
1.20 .31
16.79
6.72
15.41
6.97
13.85
4.75
13.10
5.70
None of t h e differences b e t w e e n m a t e d and u n m a t e d birds were significantly different at 5% level. Fat deposited from left and right anterior edge sartorius muscle was c o m b i n e d and weighed.
chickens (Singh and Essary, 1974). Thigh meat (deboned) weight was significantly greater (P<.05) in mated than unmated birds (8.64 vs 8.10 g). If mated birds were more active than unmated ones, this could account for greater muscle development and greater weight. There were significant differences between the mated and unmated birds for thigh skin weight (P<.01) and percentage fat and moisture content in thigh skin (P<.01). Mated birds had a higher thigh skin weight, a lower percentage fat in the thigh skin, and greater percentage moisture than unmated birds. These differences could be accounted for by the size of the thighs. Percentage fat in the thigh was about 1.3 times that in the breast, which was less than the 3.5 times reported by Singh and Essary (1974) for chickens. Percentage fat in the breast skin was higher on a wet basis than in the thigh skin in mated birds. In unmated birds the percentage fat in the breast skin was lower than fat in the thigh skin. Fat content in the crop collar plus fat at the edge of breast muscle was 2.6% of live weight, and depot fat attached to the sartorius muscle was .7%. No difference (P<.05) was found between mated and unmated birds for either fat in the crop collar plus fat at the edge of breast muscle or sartorius fat (Table 4). Correlation coefficients between abdominal fat and fat in different locations are given in Table 5. The correlations were all statistically different from zero (P<.01). There was a positive relationship between abdominal fat
percentage and percentage fat of breast muscle, percentage fat of breast skin, percentage fat of thigh muscle, and percentage fat of thigh skin. The relationship between percentage fat and percentage moisture content was determined in the breast muscle and breast skin (Table 6). The correlation coefficients were highly negative (—.76, —.99). There was no significant difference in the correlations between the mated and unmated birds. These results indicate that selection against abdominal fat would probably reduce fat at other locations because of the high correlations
T A B L E 5. Correlation coefficients between percentage abdominal fat and percentage fat at other locations Fat location % Crop collar plus fat at t h e edge of breast muscle, live weight % Sartorius muscle d e p o t fat, a live weight % Crop collar fat plus fat at t h e edge of breast muscle, breast muscle weight % Sartorius muscle d e p o t fat, thigh muscle weight % Fat of wet sample of breast muscle % Fat of dry sample breast muscle % Fat in wet breast skin % Fat in dried breast skin % Fat in wet sample of thigh muscle % Fat in wet thigh skins % Fat in dried thigh skins
r
.79 .79 .72 .77 .65 .67 .74 .72 .57 .71 .73
a F a t deposits from left and right sartorius muscles were c o m b i n e d and weighed.
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Crop collar fat plus fat at posterior edge of breast muscle weight (g) Sartorius muscle d e p o t f a t b weight (g) % Crop collar fat plus fat at the edge of breast muscle, live weight % Sartorius muscle d e p o t fat, live weight % Crop collar fat plus fat at t h e edge of breast muscle, breast muscle weight % Sartorius muscle d e p o t fat, thigh muscle weight
Unmated SD
SADJADI AND BECKER
2466
TABLE 6. Correlation coefficients between fat and moisture weights in female Coturnix quail breast muscle and skin Location
r
Breast muscle Breast skin
-.76 -.99
ACKNOWLEDGMENTS The authors are indebted to Larry Mirosh for technical assistance. The senior author was supported, in part, by a scholarship from Ferdowsi University, Mashhad, Iran.
REFERENCES Association of Official Agricultural Chemists, 1975.
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and that Coturnix quail may be used as a pilot animal in body composition research provided due caution is taken because of the differences between species.
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