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The Influence of Dietary Fat and Environmental Temperature Upon Chick Growth and Carcass Composition1,2
The Influence of Dietary Fat and Environmental Temperature Upon Chick Growth and Carcass Composition1'2 WILLIAM C. MICKELBEEEY,3 JOHN C. ROGLER AND WILLIAM J. STADELMAN
Animal Sciences Department, Purdue University, Lafayette, Indiana ((Received for publication September 11, 1965)
investigators have demonSEVERAL strated that chicks reared at elevated
"Journal paper No. 2635 of the Purdue Agricultural Experiment Station. "This investigation was supported in part by NSF grant G-6243. 'Major portions of this study were conducted while the senior author was a Campbell Soup Fellow. Appreciation is expressed to Campbell Soup Company, Camden, New Jersey, for their support. Present address: Department of Food Science and Biochemistry, Clemson University, Clemson, South Carolina.
EXPERIMENTAL Day-old, White Hubbard cross male chicks were purchased from a commercial hatchery and grown to 4 weeks of age in electrically heated batteries. The 400 chicks were fed ad libitum a corn-soybean meal diet complete in all known nutrients but without added fat. At 28 days of age the chicks were assigned to one of 32 experimental groups (10 chicks/group) on a matched weight basis with the high and low extremes being discarded. The birds were than placed in growing batteries at either 21 or 29°C. in the Purdue University Herrick Laboratories with 16 groups assigned to each temperature chamber. Each of 4 experimental diets was fed to 4 groups of 10 birds each at both temperatures until 8 weeks of age in trial 1, and 3 groups of 10 birds each in trial 2.
313
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temperatures (8S°F. to 99°F. grow at a slower rate and consume less feed than chicks reared at "normal" temperatures (Joiner and Huston, 1957; Squibb et al., 1959; Pope, 1960; Adams et al., 1962a, b, c). Adams et al. (1962a) reported that high energy rations increased growth rate in chickens in elevated temperatures, whereas Pope (1960) obtained inconsistent results by adding fat to a ration fed to chicks in a 90°F. environment. Kleiber and Dougherty (1934) and Winchester and Kleiber (1938) concluded that the fat content of the carcass is increased and the water content decreased as the temperature in which chicks were reared was increased. Adams et al. (1962b) reported no difference in fat or moisture content of the carcass of chicks reared in 70°F. and 85°F. environments. Other investigators have demonstrated an increase in the fat content and a reduction in water content of the carcass as the dietary energy level is elevated (Hill and Dansky, 1954;
Donaldson et al., 1956; Miller et al., 1962). Fisher et al. (1962) stated that the subcutaneous fat from hens maintained at 0°C. was more unsaturated than fat from hens maintained at 21°C. or 32°C, but that there was no difference in the degree of saturation between hens maintained at 21°C. or 32°C. The change noted at 0°C. was accounted for primarily by an increase in dienoic acid. The research reported herein was designed to further study interrelationships between various types of dietary fat and environmental temperature on growth rate, feed efficiency and carcass composition.
314
W . C. MlCKELBERRY, J . C. ROGLER AND W . J . S T A D E L M A N
4
Furnished through the courtesy of Proctor and Gamble Co., Cincinnati, Ohio.
stored at 21°C. or below. Body weight and feed consumption were recorded on the 2nd and 4th weeks of each feeding trial, corresponding to the birds' age of 6 and 8 weeks. Growth was judged on the increase in body weight from 4 to 8 weeks and feed efficiency was calculated as grams of feed per gram of gain. Upon termination of trial 1 at 8 weeks of age, 4 birds were randomly selected from each treatment-replicate (group), conventionally slaughtered and subjected to moisture and fat analyses in the following manner. Breast, thigh, skin, abdominal fat and liver samples were pooled separately from each appropriate group of 4 carcasses. Samples were ground in an electric meat grinder, packaged and placed in frozen storage ( —10°C). The skin sample was obtained from the breast and thigh regions of the birds. The moisture content was determined by drying for 21 hours on a laboratory freeze dryer. A portion of the dried material was immediately transferred to a tared thimble and the fat content ascertained by extraction with peroxide-free anhydrous ethyl ether for 7 hrs. on a Soxhlet apparatus. Iodine values (Hanus) were determined upon the recovered fat samples by A.O.A.C. (1955) procedures, and the total cholesterol by the Sperry and Webb (1950) method. The fatty acid composition of the abdominal and liver fats were ascertained by gasliquid chromatography. Fat samples were saponified and acidified followed by extraction of the free fatty acids with diethyl ether and conversion of the free fatty acids to the methyl esters by refluxing for 2 hours in dry methanol and 1% H 2 S0 4 . Quantitative analyses of the methyl esters were conducted in an Aerograph Model 350-B gas chromatograph with thermal conductivity detectors and the following column conditions: length, 10 ft.; packing,
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The composition of the basal diet in percentage of the total ration was as follows: ground yellow corn, 53.18; soybean meal (50% protein), 32.0; vitamin premix, 3.0; cerelose, 10.0; dicalcium phospate, 2.2; limestone. 0.9; iodized sodium chloride, 0.45; manganese sulfate, 0.05; zinc oxide, 0.007; Tenox 2 (food grade antioxidant), 0.01; DL-methionine, 0.15. Ten percent of the following fats were substituted for cerelose to provide diets for comparison: refined corn oil, prime steam lard,4 hydrogenated coconut oil (HCO) .4 The vitamin premix supplied the following in amounts per 100 gm. of diet: vitamin A, 1000 I.U.; vitamin D 3 , 150 I.C.U.; vitamin E acetate, 0.56 I.U.; choline chloride, 166 mg.; niacin, 3.17 mg.; D-calcium pantothenate, 1.41 mg.; riboflavin, 0.71 mg.; menadione sodium bisulfite, 0.11 mg.; procaine penicillin, 0.44 mg.; vitamin B12, 0.66 [jig. The determined iodine values (Hanus, A.O.A.C, 1955) of the incorporated fats were: corn oil, 123.2; lard, 62.6; and HCO, 1.6. Iodine values of the ether extract of each diet were: control, 117.7; corn oil, 122.7; lard, 74.8; and HCO, 22.4. Values for the ration samples were somewhat higher than those of the respective fat because of a small quantity (approx. 2%) of corn oil present in the ground yellow corn of the basal ration. Humidity in trial 1 was uncontrolled and varied between 16 and 48% R.H. according to barograph recordings. In trial 2 the humidity was controlled to 50 ± 1% in both environmental chambers. Lights were adjusted to furnish a 12 hr. light day. Feed was allowed ad libitum. Feed was added in small portions twice daily to the troughs to avoid excessive feed accumulation and undue oxidation of the fats. Bulk feed was
GROWTH EFFECT OF DIETARY FAT AND TEMPERATURE
315
TABLE 1.—Influence of dietary fat and ambient temperature on 4-8 week gains Temperature 21°C. Diet
Gain1
29°C.
Improvement
Cain 1
Improvement
gm ;
-
control (%)
Trial 1 Control 10% corn oil 10% lard 10% HCO 2 Av.
988" 1,104" l,126 b 1,039" 1,064
— 11.7 14.0 5.2 10.3
920° l.OOS 11 978d« 944™ 962
— 9.2 6.3 2.6 6.0
6.8 9.0 13.1 9.1 9.5
Trial 2 Control 10% corn oil 10% lard 10% HCO 2 Av.
968* l,046 b 1,101" 1,036" 1,038
— 8.0 13.7 7.0 9.6
914° 996<*° l,014 d ° 960°° 971
— 9.0 10.9 5.0 8.3
5.6 4.8 7.9 7.4 6.4
^
8
-
control (%)
Within each trial, gains with the same superscript are not significantly different (P>.05). Hydrogenated coconut oil.
20% diethylene glycol succinate on 30-60 mesh fire brick; temperature, 210°C; and gas flow rate, approx. 100 ml. He/min. Data were analyzed by the analysis of variance (Snedecor, 1959) and the sites of significance were ascertained by the Newman-Keuls test (Duncan, 1955). RESULTS AND DISCUSSION Growth data from the two feeding trials are presented in Table 1. Improved growth resulted in all cases when fat was added to the diet. The response obtained from the corn oil and lard diets were significant (P < .05) in both experiments and in both temperatures. In general, corn oil and lard elicited similar responses with HCO producing consistent but, with the exception of trial 2 at 21°C., statistically insignificant increases in growth rate. The smaller response from HCO probably can be attributed to poor utilization of the lipid since the diet undoubtedly had sufficient linoleic acid to fulfill an essential fatty acid requirement. In agreement with previous work in these environmental chambers (Adams et
al., 1962a, b, c), the 29°C. temperature retarded growth as compared with 21°C. The extent of this retardation is noted in the last column of Table 1. Although growth rate was improved in both environments by dietary fats, the magnitude of the response, in general, was greater in the 21°C. environment than in the 29°C. environment. At 21°C. birds grown on the corn oil, lard and HCO enriched diets consumed 6.0, 6.1 and 6.2%, respectively, less feed than birds fed the control diet. In the 29°C. environment these differences were 4.7, 6.3, and 7.7% for the corn oil, lard and HCO enriched diets, respectively. On the whole, feed consumption of birds at 29°C. in trial 1 was 10.5% lower than that of birds at 21°C, and 19.0% lower in trial 2. The feed conversion values for trials 1 and 2 are itemized in Table 2. The'extent to which feed utilization was improved by incorporating a fat into the diet is readily discernible from these data. In all cases, the poorest conversion occurred with the low fat control diet, which was significantly different from all other diets (P < 0.01). The corn oil and lard diets resulted in
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1
[gm )
Percent decrease from 21°C.
316
W . C. MlCKELBERRY, J . C. ROGLER AND W . J . S T A D E L M A N TABLE 2.—Influence of dietary fat and ambient temperature on 4-8 week feed conversion1 Temperat :ure Diet
6-8 wks.
Trial 1 Control Corn oil Lard HCO 3 Av.
2.05 1.85 1.72 1.91 1.88
2.70 2.12 2.18 2.31 2.33
Trial 2 Control Corn oil Lard HCO 3 Av.
2.46 1.90 1.88 1.96 2.05
2.61 2.18 2.08 2.15 2.26
1
2
4-6 wks.
6-8 wks.
4-8 wks.
2.38* 2.00 b 1.96b 2.12 b 2.12
2.09 1.83 1.70 1.89 1.88
2.46 2.14 2.24 2.20 2.26
2.29* 2.00 b 1.97" 2.06 b 2.08
2.55" 2.05 b 1.99b 2.07 b 2.16
2.18 1.84 1.90 1.96 1.97
2.51 2.12 2.16 2.29 2.27
2.36° 1.99b 2.04 b 2.08 b 2.12
4-8 wks.
Grams of feed per gram of gain. Within each trial, values with the same superscript are not significantly different (P>.05). Hydrogenated coconut oil.
similar low feed conversion ratios. No significant overall main effect of temperature on feed conversion was obtained, and only in trial 2 was there a significant difference between temperatures which occurred only with the low fat control diet. The moisture, ether extract, iodine, and cholesterol values ascertained for the various samples are shown in Table 3. Elevating the environmental temperature had no significant influence upon the moisture content whereas dietary treatments resulted in significant differences (P < 0.01). Samples derived from birds fed the low fat control diet contained the greatest quantity of water while samples from birds fed hydrogenated coconut oil, corn oil and lard diets contained progressively less. All were significantly different from each other (P < 0.01) except for samples from birds fed corn oil and lard. In respect to individual tissues, the breast was noted to contain the highest quantity of moisture, with the thigh, liver, skin, and abdominal fat having progressively lesser amounts. These differences were significant (P < 0.01) one from the
other except for breast, thigh and liver which were not significantly different from each other. The ether extract of each sample was determined on a lyophilized sample and reconverted to the wet basis using the previously determined moisture values. The fat content of the liver and breast was not significantly altered by the fats fed, while the thigh muscle ether extract was increased by lard (P < 0.01) and corn oil ( P < 0 . 0 5 ) , but not by HCO. All three fats increased the ether extractable lipids in both the abdominal fat and skin by a highly significant (P < 0.01) degree. A greater increase in these latter two tissues, considered to be fat storage depots, would be expected. The elevated environmental temperature had no significant influence upon the ether extract quantities. However, an interesting trend was noted in that, with the exception of the liver, the 29°C. HCO samples contained more fat than the 21°C. HCO samples—the only diet to consistently show this effect. The feed efficiency ratio in trial 1, from which these samples originated,
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4-6 wks.
2
29°C.
21°C.
317
GROWTH EFFECT OF DIETARY FAT AND TEMPERATURE TABLE 3.—Broiler tissue analyses as affected by diet lipid and environmental temperature 21°C.
Moisture (%) Breast Thigh Skin Abdominal fat Liver Av.
Av. Iodine No. (Hanus) Breast Thigh Skin Abdominal fat Liver Av. Cholesterol2 Breast Thigh Skin Abdominal fat Liver Av. 1 2
Low fat
Corn oil
Lard
HCO
Av.
Low fat
Corn oil
Lard
HCO
Av.
75.0 74.6 59.2 24.0 72.4
74.6 71.9 52.5 14.8 72.3
73.3 72.5 50.0 13.8 71.2
74.8 73.3 55.6 21.2 72.1
74.4 73.1 54.3 18.4 72.0
75.2 75.0 62.3 25.3 74.0
74.6 73.2 54.4 16.0 72.9
74.6 71.8 53.1 15.9 72.0
74.5 73.1 52.5 17.1 74.2
74.7 73.3 55.6 18.6 73.3
61.0
57.2
56.2
59.4
58.4
62.4
58.2
57.5
58.3
59.1
0.9 4.4 27.9 72.1 2.8
1.1 7.6 36.0 82.0 3.1
2.3 7.5 37.5 84.1 3.6
0.8 6.6 32.0 76.4 3.0
1.3 6.5 33.4 78.6 3.1
1.1 4.6 24.6 71.0 2.5
1.6 7.1 33.5 81.4 3.2
1.4 7.4 36.4 82.3 3.7
1.6 6.7 36.8 80.9 2.8
1.4 6.4 32.8 78.9 3.0
21.6
26.0
27.0
23.8
24.6
20.8
25.4
26.2
25.8
24.5
80.2 82.0 78.4 75.9 101.5
111.6 110.3 110.2 115.6 110.4
79.2 76.6 75.7 71.7 95.8
53.4 48.7 46.3 44.0 91.3
81.1 79.4 77.6 76.8 99.8
75.9 79.8 78.4 77.0 99.0
110.6 110.4 110.8 116.1 111.5
78.3 76.0 76.1 77.2 94.7
49.3 48.8 46.9 41.2 87.1
78.5 78.6 78.0 77.9 98.1
83.6
111.6
79.8
56.7
82.9
82.0
111.9
80.5
54.7
82.3
52.0 55.1 88.6 96.4 120.0 120.6 69.2 63.9 374.2 385.4
61.6 87.2 105.8 55.0 334.3
56.1 85.3 99.0 55.0 378.4
56.2 89.4 111.4 60.8 370.6
51.6 89.3 116.2 65.8 413.2
57.4 87.7 114.6 62.8 373.4
63.1 42.2 96.6 50.0 395.4
64.8 83.6 99.2 44.4 338.1
59.2 75.7 106.7 55.8 380.0
140.8
128.8
134.8
137.7
147.2
139.2
129.5
126.0
135.5
146.3
Percent of wet tissue. Total cholesterol in mg./lOO gm. wet tissue.
was slightly better for hydrogenated coconut oil in the 29°C. environment than it was at 21°C. Perhaps highly saturated fats such as this are better utilized by the chicken when fed at higher temperatures. In considering the several tissues, abdominal fat contains the greatest quantity of ether extract, succeeded in descending order by the skin, thigh, liver, and breast. Each was significantly different (P < 0.01) from the other. The lard diet in general produced the greatest increase in fat as
compared to the controls and also the greatest decrease in moisture content. The greatest quantities of cholesterol were found in the liver, as expected, followed in decreasing order by skin, thigh and then breast and abdominal fat, which had approximately the same concentrations. Environmental temperature did not influence tissue cholesterol levels. In general, the cholesterol content of most tissues appeared to be slightly lower from birds fed lard and HCO as compared with corn
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Ether Extract (%) 1 Breast Thigh Skin Abdominal fat Liver
29°C.
318
W . C. MlCKELBERRY, J . C. ROGLER AND W . J . STADELMAN
The response of liver tissue to a change in iodine value by the various dietary fats is similar to other tissues but less pronounced. The liver seems to be more resistant to a change. Reiser (1950) noted that the organ lipids of chicks on a fat-free ration tended to retain the higher polyunsaturated fatty acids more tenaciously than the carcass lipids. This same tendency seems to be evident when birds are on a fat-containing diet. The fatty acid analyses of two selected tissue lipids are shown in Table 4. The influence of dietary lipid on carcass lipid can readily be observed by a comparison of the tissue fatty acid content with that of the dietary fast. Similar observations have
been reported by others (Cruickshank, 1934; Machlin and Gordon, 1961; Marion and Edwards, 1963; Marion and Woodruff, 1963; Rogler and Carrick, 1964). When compared with the low fat control, corn oil produced an increase in linoleic acid primarily at the expense of oleic and palmitic, and to a lesser extent, at the expense of palmitoleic and stearic. Dietary hydrogenated coconut oil resulted in an increase in the concentrations of lauric and myristic acids and a reduction in palmitic, palmitoleic, oleic and linoleic acids. Lard had less effect, but in general resulted in an increase in oleic acid and a reduction in palmitic, palmitoleic and linoleic acids. It is of interest to compare the fatty acid composition of liver with that of abdominal fat. This can best be noted on the low-fat control where the influence of diet is minimal. One large difference is the high concentration of arachidonic acid in the liver whereas arachidonic could not be detected in abdominal fat with the instrument used. Machlin and Gordon (1961) also reported large quantities of arachidonic acid in liver lipid and nearly complete absence in adipose tissue. Another striking difference is the large proportion of stearic acid in the liver as compared with abdominal fat. These differences are compensated for primarily by a lower concentration of oleic acid in liver lipid. The results on the influence of dietary fat on fatty acid content of tissues parallel the effects on iodine values, and confirm the observation that the liver lipid is much more resistant to change than is abdominal fat. This is best demonstrated by comparing the increased concentrations of linoleic acid and short chain fatty acids in liver and abdominal fat as a result of feeding corn oil and HCO, respectively. Environmental temperature did not appear to affect tissue fatty acid composition
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oil and the low-fat diet. In all tissues, the major portion of this sterol was found in the free form. Tissues from birds reared in the 21°C. environment contained the following percentages of cholesterol esters (% of total cholesterol): breast, 3.2; thigh, 4.0; skin, 3.8; abdominal fat, 2.4; liver, 18.6. The values from birds in the 29°C. environment were 1-2% lower. Iodine values in Table 3 demonstrate an overall trend for a shift in the carcass values toward that of the dietary fat. Unsaturated fats such as corn oil result in greater unsaturation of tissue lipids as compared with controls, whereas saturated fats such as HCO result in an increase in the saturated lipids in the tissues. There also appears to be an association in non-organ tissues between the degree of change and the fat content of the tissue. This is most pronounced in the HCO samples—the higher iodine value being noted in the low fat breast tissue and gradually decreasing in the thigh and skin and the lowest value being recorded for the abdominal fat. Statistically, the effect of diet was highly significant (P < 0.01), but the temperature treatments were insignificant.
GROWTH E F F E C T OF DIETARY FAT AND TEMPERATURE
319
TABLE 4.—Fatty acid analysis of abdominal and liver lipids expressed as percent of total. Fatty acid1
Al 2 A5 Av.
Av.
14:0
14:1
16:0
16:1
18:0
18:1
18:2
18:3 or 20:0
—
* *
1.00 1.02
0.34 0.38
27.28 28.86
6.64 7.73
7.08 7.16
37.57 34.87
18.80 19.41
0.50 0.55
—
—
—
1.01
0.36
28.32
7.18
7.12
36.22
19.11
0.52
—
—
—
* * *
0.38 0.36
—
15.10 15.82
1.71 1.64
3.68 3.64
29.64 30.25
48.68 47.51
0.80 0.78
—
—
— * * *
*
0.37
—
15.46
1.68
3.66
29.94
48.10
0.79
—
* * *
1.76 1.44
—
26.82 26.33
4.24 4.60
8.36 7.70
42.80 43.46
14.63 16.10
0.73 0.62
—
1.60
—
26.58
4.42
8.03
43.13
15.36
0.68
—
13.38 12.76
1.38 1.10
17.44 19.68
3.54 3.58
6.68 7.10
16.60 16.98
10.74 10.03
0.40 0.26
10:0
—
A3 A7 Av. A4 A8 Av. LI L5 Av. L2 L6 Av. L3 L7 Av. L4 L8 Av.
27.61 26.33
20:4
0.28 0.22
1.74 1.84
0.25
1.79
26.97
13.07
1.24
18.56
3.56
6.89
16.79
10.39
0.33
—
* *
* *
*
0.50 0.68
* *
26.74 28.06
3.16 3.96
18.53 16.57
22.53 24.66
19.13 18.39
0.22 0.46
9.33 7.42
* * *
* * *
* * *
0.59
*
27.40
3.56
17.55
23.44
18.76
0.34
8.38
0.39 0.40
—
19.38 20.06
1.22 1.04
13.96 16.16
18.04 18.06
37.20 35.04
0.18 0.44
9.62 8.50
* * *
*
*
0.40
—
19.72
1.13
15.06
18.05
36.12
0.31
9.06
0.15 0.05
0.82 0.98
—
25.18 26.34
2.08 3.43
16.53 11.51
29.48 36.78
17.94 16.58
0.36 0.56
7.50 3.74
*
* * *
0.10
0.90
—
25.66
2.76
14.02
33.13
17.26
0.46
5.62
0.08 0.11
0.40 0.56
8.60 10.80
5.35 6.96
0.31 0.45
24.60 22.78
1.69 1.77
18.36 16.96
16.03 14.56
16.64 17.67
0.46 0.44
7.52 6.94
0.10
0.48
9.70
6.16
0.38
23.69
1.73
17.66
15.30
17.15
0.45
7.23
*
1.73 13.31 10.66
28.82 45.38 0.98
56.56 10.64 0.61
1.12
Diet fats CO Lard HCO
8.73
* 7.70
* 48.28
1.68 15.54
—
11.88 25.91 7.51
3.08
—
1
Chain length: number of double bonds. A—abdominal lipid 3—10% lard, 21°C. 6—10% L—liver lipid 4—10% hydrogenated coconut oil 7—10% 1—control, 21°C. (HCO), 21°C. 8—10% 2—10% com oil (CO), 21°C. 5—control, 29°C. Each value given for a treatment represents the average of two replicates consisting of from five birds each. * Trace. 2
CO, 29°C. lard, 29°C. HCO, 29°C. pooled samples
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A2 A6
12:0
8:0
320
W . C. MlCKELBERRY, J . C. ROGLER AND W . J . SlADELMAN
in any of the dietary treatments. These results agree with Fisher et al. (1962) who only noted differences in tissue fatty acid concentrations when hens were maintained at a low temperature (0°C), and did not observe differences when hens maintained at 21°C. were compared with those maintained at 32°C. SUMMARY
REFERENCES Adams, R. L., F. N. Andrews, E. E. Gardiner, W. E. Fontaine and C. W. Carrick, 1962a. The effects of environmental temperature on the growth and nutritional requirements of the chick. Poultry Sci. 4 1 : 588-594. Adams, R. L., F. N. Andrews, J. C. Rogler and C. W. Carrick, 1962b. The protein requirement of 4-week-old chicks as affected by temperature. J. Nutrition, 77 : 121-126. Adams, R. L., F. N. Andrews, J. C. Rogler and C. W. Carrick, 1962c. The sulfur amino acid requirement of the chick from 4 to 8 weeks of age as affected by temperature. Poultry Sci. 41:1801-1806. Association of Official Agricultural Chemists, 1955. Methods of Analysis. 8th ed. Washington, D. C. Cruickshank, E. M., 1934. Studies in fat metabolism in the fowl. I. The composition of the egg fat and depot fat of the fowl as affected by the ingestion of large amounts of different fats. Biochem. J. 28: 965-977. Donaldson, W. E., G. F. Combs and G. L. Romoser, 1956. Studies on energy levels in poultry rations. 1. The effect of calorie-protein ratio of the ration on growth, nutrient utilization and body composition of chickens. Poultry Sci. 35: 1100-1105. Duncan, D. B., 1955. Multiple range and F tests. Biometrics, 11: 1-42. Fisher, H., K. G. Hollands and H. S. Weiss, 1962. Environmental temperature and composition of body fat. Proc. Soc. Exp. Biol. Med. 110:832833. Hill, F. W., and L. M. Dansky, 1954. Studies of the energy requirements of chickens. 1. The effect of dietary energy level or growth and feed consumption. Poultry Sci. 33: 112-119. Joiner, W. P., and T. M. Huston, 1957. The influence of high environmental temperature on immature domestic fowl. Poultry Sci. 36: 973. Kleiber, M„ and J. E. Dougherty, 1934. The influence on environmental temperature on the utilization of food energy in baby chicks. J. Gen. Physiol. 17 : 701-726. Machlin, L. J., and R. S. Gordon, 1961. Effect of dietary fatty acids and cholesterol on growth
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Four diets containing either 10% cerelose, corn oil, lard or hydrogenated coconut oil as variables were fed to broilers at two environmental temperatures (21° and 29°C.) from 4-8 weeks of age. From randomly selected 8 week birds, breast, thigh, skin, abdominal fat and liver samples were analyzed for moisture, ether extract, degree of saturation, and total cholesterol content. Bi-weekly growth and feed conversion data were computed. Liver and abdominal lipids were subjected to gas chromatographic separation of their component fatty acids. The elevated temperature markedly retarded growth and feed consumption but had no significant influence upon either the moisture, fat content, iodine value, total cholesterol content, or the fatty acid composition. Incorporation of fat into the diet improved both growth and feed conversion in all cases. Diets exerted a marked effect upon all attributes analyzed. An overall trend of the carcass fat to be similar to the derived dietary fat in both iodine value and fatty acid composition was observed. Differences between tissues were noted in their response to dietary fat with abdominal fat being the least resistant to change and liver lipid the most resistant to change. Liver lipid was found to contain much higher concentrations of stearic and arachidonic acids and lower concentration of oleic acid than abdominal lipid regardless of dietary treatment. Liver lipids contained the greatest quan-
tity of cholesterol, followed by the skin and thigh, with the breast and abdominal fat having minimal amounts. Cholesterol in all tissues was found present predominantly in the free form.
GROWTH EFFECT OF DIETARY FAT AND TEMPERATURE
Rogler, J. C , and C. W. Carrick, 1964. Studies on raw and heated unextracted soybeans for layers. Poultry Sci. 43 : 605-612. Snedecor, G. W., 1959. Statistical Methods, 5th ed. The Iowa State College Press, Ames, Iowa. Sperry, W. M., and M. Webb, 1950. A revision of the Schoenheimer-Sperry method for cholesterol determination. J. Biol. Chem. 187: 97106. Squibb, R. L., M. A. Guzman and N. S. Scrimshaw, 1959. Growth and blood constituents of immature New Hampshire fowl exposed to a constant temperature of 99 °F. for 7 days. Poultry Sci. 38: 220-221. Winchester, C. F., and F. Kleiber, 1938. The effect of environmental temperature on mortality, rate of growth, and utilization of food energy in White Leghorn chicks. J. Agr. Res. 57: 529S44.
Depletion of D D T from Commercial Layers1'2 R. L. WESLEY, 3 A. R. STEMP, B. J. LISKA AND W. J. STADELMAN Department of Animal Sciences, Purdue University, Lafayette, Indiana ((Received for publication September 11, 1965) INTRODUCTION
HE use of DDT and other pesticides to control flies, insects, etc., in poultry houses is a common practice. In addition, DDT and other pesticides are recommended for use in feed grain production (U.S.D.A., 1965). Unless the most careful application of these chemicals is accomplished, some will inadvertently get into the feed and/or water, and will result in a
T
1 Journal Paper No. 2619 of the Purdue Agricultural Experiment Station. 2 This investigation was supported in part by a grant from the American Poultry and Hatchery Federation, Kansas City, Missouri and by PHS Research Grant EF-OO049-O2 from the Division of Environmental Engineering and Food Protection, U.S. Public Health Service. 3 On educational leave from Virginia Polytechnic Institute.
residual buildup in the eggs and meat. Various workers (Naber and Ware, 1961; Liska, et al., 1964; Stadelman et al., 1965) have reported residues of chlorinated insecticides in tissues and eggs of chickens exposed to these insecticides. Recent attention focused on DDT residues in eggs has resulted in condemnation of several lots of eggs by government agencies in the midwest and other areas of the U.S. Though pesticide residues in meat and eggs may be a potential human health hazard, no tolerance level has as yet been set by the Food and Drug Administration. The objective of this investigation was to determine the effect of management practices on the depletion of DDT residues in the abdominal fat and egg yolks of commercial layers following a measured exposure to the insecticide.
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and fatty acid composition of the chicken. J. Nutrition, 75: 157-164. Marion, J. E., and H. M. Edwards, Jr., 1963. The effect of age on the response of chickens to dietary protein and fat. J. Nutrition, 79: 53-61. Marion, J. E., and J. G. Woodroof, 1963. The fatty acid composition of breast, thigh and skin tissues of chicken broilers as influenced by dietary fats. Poultry Sci. 42: 1202-1207. Miller, E. C , H. Menge and C. A. Denton, 1962. Effect of dietary fat on tissue fat and plasma cholesterol level in broilers. Poultry Sci. 4 1 : 970-974. Pope, D. L., 1960. Nutrition and environmental temperature studies with broilers. Proc. Univ. Maryland Nutr. Conf. Feed Mfg. 48-53. Reiser, R., 1950. The metabolism of polyunsaturated fatty acids in growing chicks. J. Nutrition, 42: 325-330.
321
Animal Sciences Department, Purdue University, Lafayette, Indiana ((Received for publication September 11, 1965)
investigators have demonSEVERAL strated that chicks reared at elevated
"Journal paper No. 2635 of the Purdue Agricultural Experiment Station. "This investigation was supported in part by NSF grant G-6243. 'Major portions of this study were conducted while the senior author was a Campbell Soup Fellow. Appreciation is expressed to Campbell Soup Company, Camden, New Jersey, for their support. Present address: Department of Food Science and Biochemistry, Clemson University, Clemson, South Carolina.
EXPERIMENTAL Day-old, White Hubbard cross male chicks were purchased from a commercial hatchery and grown to 4 weeks of age in electrically heated batteries. The 400 chicks were fed ad libitum a corn-soybean meal diet complete in all known nutrients but without added fat. At 28 days of age the chicks were assigned to one of 32 experimental groups (10 chicks/group) on a matched weight basis with the high and low extremes being discarded. The birds were than placed in growing batteries at either 21 or 29°C. in the Purdue University Herrick Laboratories with 16 groups assigned to each temperature chamber. Each of 4 experimental diets was fed to 4 groups of 10 birds each at both temperatures until 8 weeks of age in trial 1, and 3 groups of 10 birds each in trial 2.
313
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temperatures (8S°F. to 99°F. grow at a slower rate and consume less feed than chicks reared at "normal" temperatures (Joiner and Huston, 1957; Squibb et al., 1959; Pope, 1960; Adams et al., 1962a, b, c). Adams et al. (1962a) reported that high energy rations increased growth rate in chickens in elevated temperatures, whereas Pope (1960) obtained inconsistent results by adding fat to a ration fed to chicks in a 90°F. environment. Kleiber and Dougherty (1934) and Winchester and Kleiber (1938) concluded that the fat content of the carcass is increased and the water content decreased as the temperature in which chicks were reared was increased. Adams et al. (1962b) reported no difference in fat or moisture content of the carcass of chicks reared in 70°F. and 85°F. environments. Other investigators have demonstrated an increase in the fat content and a reduction in water content of the carcass as the dietary energy level is elevated (Hill and Dansky, 1954;
Donaldson et al., 1956; Miller et al., 1962). Fisher et al. (1962) stated that the subcutaneous fat from hens maintained at 0°C. was more unsaturated than fat from hens maintained at 21°C. or 32°C, but that there was no difference in the degree of saturation between hens maintained at 21°C. or 32°C. The change noted at 0°C. was accounted for primarily by an increase in dienoic acid. The research reported herein was designed to further study interrelationships between various types of dietary fat and environmental temperature on growth rate, feed efficiency and carcass composition.
314
W . C. MlCKELBERRY, J . C. ROGLER AND W . J . S T A D E L M A N
4
Furnished through the courtesy of Proctor and Gamble Co., Cincinnati, Ohio.
stored at 21°C. or below. Body weight and feed consumption were recorded on the 2nd and 4th weeks of each feeding trial, corresponding to the birds' age of 6 and 8 weeks. Growth was judged on the increase in body weight from 4 to 8 weeks and feed efficiency was calculated as grams of feed per gram of gain. Upon termination of trial 1 at 8 weeks of age, 4 birds were randomly selected from each treatment-replicate (group), conventionally slaughtered and subjected to moisture and fat analyses in the following manner. Breast, thigh, skin, abdominal fat and liver samples were pooled separately from each appropriate group of 4 carcasses. Samples were ground in an electric meat grinder, packaged and placed in frozen storage ( —10°C). The skin sample was obtained from the breast and thigh regions of the birds. The moisture content was determined by drying for 21 hours on a laboratory freeze dryer. A portion of the dried material was immediately transferred to a tared thimble and the fat content ascertained by extraction with peroxide-free anhydrous ethyl ether for 7 hrs. on a Soxhlet apparatus. Iodine values (Hanus) were determined upon the recovered fat samples by A.O.A.C. (1955) procedures, and the total cholesterol by the Sperry and Webb (1950) method. The fatty acid composition of the abdominal and liver fats were ascertained by gasliquid chromatography. Fat samples were saponified and acidified followed by extraction of the free fatty acids with diethyl ether and conversion of the free fatty acids to the methyl esters by refluxing for 2 hours in dry methanol and 1% H 2 S0 4 . Quantitative analyses of the methyl esters were conducted in an Aerograph Model 350-B gas chromatograph with thermal conductivity detectors and the following column conditions: length, 10 ft.; packing,
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The composition of the basal diet in percentage of the total ration was as follows: ground yellow corn, 53.18; soybean meal (50% protein), 32.0; vitamin premix, 3.0; cerelose, 10.0; dicalcium phospate, 2.2; limestone. 0.9; iodized sodium chloride, 0.45; manganese sulfate, 0.05; zinc oxide, 0.007; Tenox 2 (food grade antioxidant), 0.01; DL-methionine, 0.15. Ten percent of the following fats were substituted for cerelose to provide diets for comparison: refined corn oil, prime steam lard,4 hydrogenated coconut oil (HCO) .4 The vitamin premix supplied the following in amounts per 100 gm. of diet: vitamin A, 1000 I.U.; vitamin D 3 , 150 I.C.U.; vitamin E acetate, 0.56 I.U.; choline chloride, 166 mg.; niacin, 3.17 mg.; D-calcium pantothenate, 1.41 mg.; riboflavin, 0.71 mg.; menadione sodium bisulfite, 0.11 mg.; procaine penicillin, 0.44 mg.; vitamin B12, 0.66 [jig. The determined iodine values (Hanus, A.O.A.C, 1955) of the incorporated fats were: corn oil, 123.2; lard, 62.6; and HCO, 1.6. Iodine values of the ether extract of each diet were: control, 117.7; corn oil, 122.7; lard, 74.8; and HCO, 22.4. Values for the ration samples were somewhat higher than those of the respective fat because of a small quantity (approx. 2%) of corn oil present in the ground yellow corn of the basal ration. Humidity in trial 1 was uncontrolled and varied between 16 and 48% R.H. according to barograph recordings. In trial 2 the humidity was controlled to 50 ± 1% in both environmental chambers. Lights were adjusted to furnish a 12 hr. light day. Feed was allowed ad libitum. Feed was added in small portions twice daily to the troughs to avoid excessive feed accumulation and undue oxidation of the fats. Bulk feed was
GROWTH EFFECT OF DIETARY FAT AND TEMPERATURE
315
TABLE 1.—Influence of dietary fat and ambient temperature on 4-8 week gains Temperature 21°C. Diet
Gain1
29°C.
Improvement
Cain 1
Improvement
gm ;
-
control (%)
Trial 1 Control 10% corn oil 10% lard 10% HCO 2 Av.
988" 1,104" l,126 b 1,039" 1,064
— 11.7 14.0 5.2 10.3
920° l.OOS 11 978d« 944™ 962
— 9.2 6.3 2.6 6.0
6.8 9.0 13.1 9.1 9.5
Trial 2 Control 10% corn oil 10% lard 10% HCO 2 Av.
968* l,046 b 1,101" 1,036" 1,038
— 8.0 13.7 7.0 9.6
914° 996<*° l,014 d ° 960°° 971
— 9.0 10.9 5.0 8.3
5.6 4.8 7.9 7.4 6.4
^
8
-
control (%)
Within each trial, gains with the same superscript are not significantly different (P>.05). Hydrogenated coconut oil.
20% diethylene glycol succinate on 30-60 mesh fire brick; temperature, 210°C; and gas flow rate, approx. 100 ml. He/min. Data were analyzed by the analysis of variance (Snedecor, 1959) and the sites of significance were ascertained by the Newman-Keuls test (Duncan, 1955). RESULTS AND DISCUSSION Growth data from the two feeding trials are presented in Table 1. Improved growth resulted in all cases when fat was added to the diet. The response obtained from the corn oil and lard diets were significant (P < .05) in both experiments and in both temperatures. In general, corn oil and lard elicited similar responses with HCO producing consistent but, with the exception of trial 2 at 21°C., statistically insignificant increases in growth rate. The smaller response from HCO probably can be attributed to poor utilization of the lipid since the diet undoubtedly had sufficient linoleic acid to fulfill an essential fatty acid requirement. In agreement with previous work in these environmental chambers (Adams et
al., 1962a, b, c), the 29°C. temperature retarded growth as compared with 21°C. The extent of this retardation is noted in the last column of Table 1. Although growth rate was improved in both environments by dietary fats, the magnitude of the response, in general, was greater in the 21°C. environment than in the 29°C. environment. At 21°C. birds grown on the corn oil, lard and HCO enriched diets consumed 6.0, 6.1 and 6.2%, respectively, less feed than birds fed the control diet. In the 29°C. environment these differences were 4.7, 6.3, and 7.7% for the corn oil, lard and HCO enriched diets, respectively. On the whole, feed consumption of birds at 29°C. in trial 1 was 10.5% lower than that of birds at 21°C, and 19.0% lower in trial 2. The feed conversion values for trials 1 and 2 are itemized in Table 2. The'extent to which feed utilization was improved by incorporating a fat into the diet is readily discernible from these data. In all cases, the poorest conversion occurred with the low fat control diet, which was significantly different from all other diets (P < 0.01). The corn oil and lard diets resulted in
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1
[gm )
Percent decrease from 21°C.
316
W . C. MlCKELBERRY, J . C. ROGLER AND W . J . S T A D E L M A N TABLE 2.—Influence of dietary fat and ambient temperature on 4-8 week feed conversion1 Temperat :ure Diet
6-8 wks.
Trial 1 Control Corn oil Lard HCO 3 Av.
2.05 1.85 1.72 1.91 1.88
2.70 2.12 2.18 2.31 2.33
Trial 2 Control Corn oil Lard HCO 3 Av.
2.46 1.90 1.88 1.96 2.05
2.61 2.18 2.08 2.15 2.26
1
2
4-6 wks.
6-8 wks.
4-8 wks.
2.38* 2.00 b 1.96b 2.12 b 2.12
2.09 1.83 1.70 1.89 1.88
2.46 2.14 2.24 2.20 2.26
2.29* 2.00 b 1.97" 2.06 b 2.08
2.55" 2.05 b 1.99b 2.07 b 2.16
2.18 1.84 1.90 1.96 1.97
2.51 2.12 2.16 2.29 2.27
2.36° 1.99b 2.04 b 2.08 b 2.12
4-8 wks.
Grams of feed per gram of gain. Within each trial, values with the same superscript are not significantly different (P>.05). Hydrogenated coconut oil.
similar low feed conversion ratios. No significant overall main effect of temperature on feed conversion was obtained, and only in trial 2 was there a significant difference between temperatures which occurred only with the low fat control diet. The moisture, ether extract, iodine, and cholesterol values ascertained for the various samples are shown in Table 3. Elevating the environmental temperature had no significant influence upon the moisture content whereas dietary treatments resulted in significant differences (P < 0.01). Samples derived from birds fed the low fat control diet contained the greatest quantity of water while samples from birds fed hydrogenated coconut oil, corn oil and lard diets contained progressively less. All were significantly different from each other (P < 0.01) except for samples from birds fed corn oil and lard. In respect to individual tissues, the breast was noted to contain the highest quantity of moisture, with the thigh, liver, skin, and abdominal fat having progressively lesser amounts. These differences were significant (P < 0.01) one from the
other except for breast, thigh and liver which were not significantly different from each other. The ether extract of each sample was determined on a lyophilized sample and reconverted to the wet basis using the previously determined moisture values. The fat content of the liver and breast was not significantly altered by the fats fed, while the thigh muscle ether extract was increased by lard (P < 0.01) and corn oil ( P < 0 . 0 5 ) , but not by HCO. All three fats increased the ether extractable lipids in both the abdominal fat and skin by a highly significant (P < 0.01) degree. A greater increase in these latter two tissues, considered to be fat storage depots, would be expected. The elevated environmental temperature had no significant influence upon the ether extract quantities. However, an interesting trend was noted in that, with the exception of the liver, the 29°C. HCO samples contained more fat than the 21°C. HCO samples—the only diet to consistently show this effect. The feed efficiency ratio in trial 1, from which these samples originated,
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4-6 wks.
2
29°C.
21°C.
317
GROWTH EFFECT OF DIETARY FAT AND TEMPERATURE TABLE 3.—Broiler tissue analyses as affected by diet lipid and environmental temperature 21°C.
Moisture (%) Breast Thigh Skin Abdominal fat Liver Av.
Av. Iodine No. (Hanus) Breast Thigh Skin Abdominal fat Liver Av. Cholesterol2 Breast Thigh Skin Abdominal fat Liver Av. 1 2
Low fat
Corn oil
Lard
HCO
Av.
Low fat
Corn oil
Lard
HCO
Av.
75.0 74.6 59.2 24.0 72.4
74.6 71.9 52.5 14.8 72.3
73.3 72.5 50.0 13.8 71.2
74.8 73.3 55.6 21.2 72.1
74.4 73.1 54.3 18.4 72.0
75.2 75.0 62.3 25.3 74.0
74.6 73.2 54.4 16.0 72.9
74.6 71.8 53.1 15.9 72.0
74.5 73.1 52.5 17.1 74.2
74.7 73.3 55.6 18.6 73.3
61.0
57.2
56.2
59.4
58.4
62.4
58.2
57.5
58.3
59.1
0.9 4.4 27.9 72.1 2.8
1.1 7.6 36.0 82.0 3.1
2.3 7.5 37.5 84.1 3.6
0.8 6.6 32.0 76.4 3.0
1.3 6.5 33.4 78.6 3.1
1.1 4.6 24.6 71.0 2.5
1.6 7.1 33.5 81.4 3.2
1.4 7.4 36.4 82.3 3.7
1.6 6.7 36.8 80.9 2.8
1.4 6.4 32.8 78.9 3.0
21.6
26.0
27.0
23.8
24.6
20.8
25.4
26.2
25.8
24.5
80.2 82.0 78.4 75.9 101.5
111.6 110.3 110.2 115.6 110.4
79.2 76.6 75.7 71.7 95.8
53.4 48.7 46.3 44.0 91.3
81.1 79.4 77.6 76.8 99.8
75.9 79.8 78.4 77.0 99.0
110.6 110.4 110.8 116.1 111.5
78.3 76.0 76.1 77.2 94.7
49.3 48.8 46.9 41.2 87.1
78.5 78.6 78.0 77.9 98.1
83.6
111.6
79.8
56.7
82.9
82.0
111.9
80.5
54.7
82.3
52.0 55.1 88.6 96.4 120.0 120.6 69.2 63.9 374.2 385.4
61.6 87.2 105.8 55.0 334.3
56.1 85.3 99.0 55.0 378.4
56.2 89.4 111.4 60.8 370.6
51.6 89.3 116.2 65.8 413.2
57.4 87.7 114.6 62.8 373.4
63.1 42.2 96.6 50.0 395.4
64.8 83.6 99.2 44.4 338.1
59.2 75.7 106.7 55.8 380.0
140.8
128.8
134.8
137.7
147.2
139.2
129.5
126.0
135.5
146.3
Percent of wet tissue. Total cholesterol in mg./lOO gm. wet tissue.
was slightly better for hydrogenated coconut oil in the 29°C. environment than it was at 21°C. Perhaps highly saturated fats such as this are better utilized by the chicken when fed at higher temperatures. In considering the several tissues, abdominal fat contains the greatest quantity of ether extract, succeeded in descending order by the skin, thigh, liver, and breast. Each was significantly different (P < 0.01) from the other. The lard diet in general produced the greatest increase in fat as
compared to the controls and also the greatest decrease in moisture content. The greatest quantities of cholesterol were found in the liver, as expected, followed in decreasing order by skin, thigh and then breast and abdominal fat, which had approximately the same concentrations. Environmental temperature did not influence tissue cholesterol levels. In general, the cholesterol content of most tissues appeared to be slightly lower from birds fed lard and HCO as compared with corn
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Ether Extract (%) 1 Breast Thigh Skin Abdominal fat Liver
29°C.
318
W . C. MlCKELBERRY, J . C. ROGLER AND W . J . STADELMAN
The response of liver tissue to a change in iodine value by the various dietary fats is similar to other tissues but less pronounced. The liver seems to be more resistant to a change. Reiser (1950) noted that the organ lipids of chicks on a fat-free ration tended to retain the higher polyunsaturated fatty acids more tenaciously than the carcass lipids. This same tendency seems to be evident when birds are on a fat-containing diet. The fatty acid analyses of two selected tissue lipids are shown in Table 4. The influence of dietary lipid on carcass lipid can readily be observed by a comparison of the tissue fatty acid content with that of the dietary fast. Similar observations have
been reported by others (Cruickshank, 1934; Machlin and Gordon, 1961; Marion and Edwards, 1963; Marion and Woodruff, 1963; Rogler and Carrick, 1964). When compared with the low fat control, corn oil produced an increase in linoleic acid primarily at the expense of oleic and palmitic, and to a lesser extent, at the expense of palmitoleic and stearic. Dietary hydrogenated coconut oil resulted in an increase in the concentrations of lauric and myristic acids and a reduction in palmitic, palmitoleic, oleic and linoleic acids. Lard had less effect, but in general resulted in an increase in oleic acid and a reduction in palmitic, palmitoleic and linoleic acids. It is of interest to compare the fatty acid composition of liver with that of abdominal fat. This can best be noted on the low-fat control where the influence of diet is minimal. One large difference is the high concentration of arachidonic acid in the liver whereas arachidonic could not be detected in abdominal fat with the instrument used. Machlin and Gordon (1961) also reported large quantities of arachidonic acid in liver lipid and nearly complete absence in adipose tissue. Another striking difference is the large proportion of stearic acid in the liver as compared with abdominal fat. These differences are compensated for primarily by a lower concentration of oleic acid in liver lipid. The results on the influence of dietary fat on fatty acid content of tissues parallel the effects on iodine values, and confirm the observation that the liver lipid is much more resistant to change than is abdominal fat. This is best demonstrated by comparing the increased concentrations of linoleic acid and short chain fatty acids in liver and abdominal fat as a result of feeding corn oil and HCO, respectively. Environmental temperature did not appear to affect tissue fatty acid composition
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oil and the low-fat diet. In all tissues, the major portion of this sterol was found in the free form. Tissues from birds reared in the 21°C. environment contained the following percentages of cholesterol esters (% of total cholesterol): breast, 3.2; thigh, 4.0; skin, 3.8; abdominal fat, 2.4; liver, 18.6. The values from birds in the 29°C. environment were 1-2% lower. Iodine values in Table 3 demonstrate an overall trend for a shift in the carcass values toward that of the dietary fat. Unsaturated fats such as corn oil result in greater unsaturation of tissue lipids as compared with controls, whereas saturated fats such as HCO result in an increase in the saturated lipids in the tissues. There also appears to be an association in non-organ tissues between the degree of change and the fat content of the tissue. This is most pronounced in the HCO samples—the higher iodine value being noted in the low fat breast tissue and gradually decreasing in the thigh and skin and the lowest value being recorded for the abdominal fat. Statistically, the effect of diet was highly significant (P < 0.01), but the temperature treatments were insignificant.
GROWTH E F F E C T OF DIETARY FAT AND TEMPERATURE
319
TABLE 4.—Fatty acid analysis of abdominal and liver lipids expressed as percent of total. Fatty acid1
Al 2 A5 Av.
Av.
14:0
14:1
16:0
16:1
18:0
18:1
18:2
18:3 or 20:0
—
* *
1.00 1.02
0.34 0.38
27.28 28.86
6.64 7.73
7.08 7.16
37.57 34.87
18.80 19.41
0.50 0.55
—
—
—
1.01
0.36
28.32
7.18
7.12
36.22
19.11
0.52
—
—
—
* * *
0.38 0.36
—
15.10 15.82
1.71 1.64
3.68 3.64
29.64 30.25
48.68 47.51
0.80 0.78
—
—
— * * *
*
0.37
—
15.46
1.68
3.66
29.94
48.10
0.79
—
* * *
1.76 1.44
—
26.82 26.33
4.24 4.60
8.36 7.70
42.80 43.46
14.63 16.10
0.73 0.62
—
1.60
—
26.58
4.42
8.03
43.13
15.36
0.68
—
13.38 12.76
1.38 1.10
17.44 19.68
3.54 3.58
6.68 7.10
16.60 16.98
10.74 10.03
0.40 0.26
10:0
—
A3 A7 Av. A4 A8 Av. LI L5 Av. L2 L6 Av. L3 L7 Av. L4 L8 Av.
27.61 26.33
20:4
0.28 0.22
1.74 1.84
0.25
1.79
26.97
13.07
1.24
18.56
3.56
6.89
16.79
10.39
0.33
—
* *
* *
*
0.50 0.68
* *
26.74 28.06
3.16 3.96
18.53 16.57
22.53 24.66
19.13 18.39
0.22 0.46
9.33 7.42
* * *
* * *
* * *
0.59
*
27.40
3.56
17.55
23.44
18.76
0.34
8.38
0.39 0.40
—
19.38 20.06
1.22 1.04
13.96 16.16
18.04 18.06
37.20 35.04
0.18 0.44
9.62 8.50
* * *
*
*
0.40
—
19.72
1.13
15.06
18.05
36.12
0.31
9.06
0.15 0.05
0.82 0.98
—
25.18 26.34
2.08 3.43
16.53 11.51
29.48 36.78
17.94 16.58
0.36 0.56
7.50 3.74
*
* * *
0.10
0.90
—
25.66
2.76
14.02
33.13
17.26
0.46
5.62
0.08 0.11
0.40 0.56
8.60 10.80
5.35 6.96
0.31 0.45
24.60 22.78
1.69 1.77
18.36 16.96
16.03 14.56
16.64 17.67
0.46 0.44
7.52 6.94
0.10
0.48
9.70
6.16
0.38
23.69
1.73
17.66
15.30
17.15
0.45
7.23
*
1.73 13.31 10.66
28.82 45.38 0.98
56.56 10.64 0.61
1.12
Diet fats CO Lard HCO
8.73
* 7.70
* 48.28
1.68 15.54
—
11.88 25.91 7.51
3.08
—
1
Chain length: number of double bonds. A—abdominal lipid 3—10% lard, 21°C. 6—10% L—liver lipid 4—10% hydrogenated coconut oil 7—10% 1—control, 21°C. (HCO), 21°C. 8—10% 2—10% com oil (CO), 21°C. 5—control, 29°C. Each value given for a treatment represents the average of two replicates consisting of from five birds each. * Trace. 2
CO, 29°C. lard, 29°C. HCO, 29°C. pooled samples
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A2 A6
12:0
8:0
320
W . C. MlCKELBERRY, J . C. ROGLER AND W . J . SlADELMAN
in any of the dietary treatments. These results agree with Fisher et al. (1962) who only noted differences in tissue fatty acid concentrations when hens were maintained at a low temperature (0°C), and did not observe differences when hens maintained at 21°C. were compared with those maintained at 32°C. SUMMARY
REFERENCES Adams, R. L., F. N. Andrews, E. E. Gardiner, W. E. Fontaine and C. W. Carrick, 1962a. The effects of environmental temperature on the growth and nutritional requirements of the chick. Poultry Sci. 4 1 : 588-594. Adams, R. L., F. N. Andrews, J. C. Rogler and C. W. Carrick, 1962b. The protein requirement of 4-week-old chicks as affected by temperature. J. Nutrition, 77 : 121-126. Adams, R. L., F. N. Andrews, J. C. Rogler and C. W. Carrick, 1962c. The sulfur amino acid requirement of the chick from 4 to 8 weeks of age as affected by temperature. Poultry Sci. 41:1801-1806. Association of Official Agricultural Chemists, 1955. Methods of Analysis. 8th ed. Washington, D. C. Cruickshank, E. M., 1934. Studies in fat metabolism in the fowl. I. The composition of the egg fat and depot fat of the fowl as affected by the ingestion of large amounts of different fats. Biochem. J. 28: 965-977. Donaldson, W. E., G. F. Combs and G. L. Romoser, 1956. Studies on energy levels in poultry rations. 1. The effect of calorie-protein ratio of the ration on growth, nutrient utilization and body composition of chickens. Poultry Sci. 35: 1100-1105. Duncan, D. B., 1955. Multiple range and F tests. Biometrics, 11: 1-42. Fisher, H., K. G. Hollands and H. S. Weiss, 1962. Environmental temperature and composition of body fat. Proc. Soc. Exp. Biol. Med. 110:832833. Hill, F. W., and L. M. Dansky, 1954. Studies of the energy requirements of chickens. 1. The effect of dietary energy level or growth and feed consumption. Poultry Sci. 33: 112-119. Joiner, W. P., and T. M. Huston, 1957. The influence of high environmental temperature on immature domestic fowl. Poultry Sci. 36: 973. Kleiber, M„ and J. E. Dougherty, 1934. The influence on environmental temperature on the utilization of food energy in baby chicks. J. Gen. Physiol. 17 : 701-726. Machlin, L. J., and R. S. Gordon, 1961. Effect of dietary fatty acids and cholesterol on growth
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Four diets containing either 10% cerelose, corn oil, lard or hydrogenated coconut oil as variables were fed to broilers at two environmental temperatures (21° and 29°C.) from 4-8 weeks of age. From randomly selected 8 week birds, breast, thigh, skin, abdominal fat and liver samples were analyzed for moisture, ether extract, degree of saturation, and total cholesterol content. Bi-weekly growth and feed conversion data were computed. Liver and abdominal lipids were subjected to gas chromatographic separation of their component fatty acids. The elevated temperature markedly retarded growth and feed consumption but had no significant influence upon either the moisture, fat content, iodine value, total cholesterol content, or the fatty acid composition. Incorporation of fat into the diet improved both growth and feed conversion in all cases. Diets exerted a marked effect upon all attributes analyzed. An overall trend of the carcass fat to be similar to the derived dietary fat in both iodine value and fatty acid composition was observed. Differences between tissues were noted in their response to dietary fat with abdominal fat being the least resistant to change and liver lipid the most resistant to change. Liver lipid was found to contain much higher concentrations of stearic and arachidonic acids and lower concentration of oleic acid than abdominal lipid regardless of dietary treatment. Liver lipids contained the greatest quan-
tity of cholesterol, followed by the skin and thigh, with the breast and abdominal fat having minimal amounts. Cholesterol in all tissues was found present predominantly in the free form.
GROWTH EFFECT OF DIETARY FAT AND TEMPERATURE
Rogler, J. C , and C. W. Carrick, 1964. Studies on raw and heated unextracted soybeans for layers. Poultry Sci. 43 : 605-612. Snedecor, G. W., 1959. Statistical Methods, 5th ed. The Iowa State College Press, Ames, Iowa. Sperry, W. M., and M. Webb, 1950. A revision of the Schoenheimer-Sperry method for cholesterol determination. J. Biol. Chem. 187: 97106. Squibb, R. L., M. A. Guzman and N. S. Scrimshaw, 1959. Growth and blood constituents of immature New Hampshire fowl exposed to a constant temperature of 99 °F. for 7 days. Poultry Sci. 38: 220-221. Winchester, C. F., and F. Kleiber, 1938. The effect of environmental temperature on mortality, rate of growth, and utilization of food energy in White Leghorn chicks. J. Agr. Res. 57: 529S44.
Depletion of D D T from Commercial Layers1'2 R. L. WESLEY, 3 A. R. STEMP, B. J. LISKA AND W. J. STADELMAN Department of Animal Sciences, Purdue University, Lafayette, Indiana ((Received for publication September 11, 1965) INTRODUCTION
HE use of DDT and other pesticides to control flies, insects, etc., in poultry houses is a common practice. In addition, DDT and other pesticides are recommended for use in feed grain production (U.S.D.A., 1965). Unless the most careful application of these chemicals is accomplished, some will inadvertently get into the feed and/or water, and will result in a
T
1 Journal Paper No. 2619 of the Purdue Agricultural Experiment Station. 2 This investigation was supported in part by a grant from the American Poultry and Hatchery Federation, Kansas City, Missouri and by PHS Research Grant EF-OO049-O2 from the Division of Environmental Engineering and Food Protection, U.S. Public Health Service. 3 On educational leave from Virginia Polytechnic Institute.
residual buildup in the eggs and meat. Various workers (Naber and Ware, 1961; Liska, et al., 1964; Stadelman et al., 1965) have reported residues of chlorinated insecticides in tissues and eggs of chickens exposed to these insecticides. Recent attention focused on DDT residues in eggs has resulted in condemnation of several lots of eggs by government agencies in the midwest and other areas of the U.S. Though pesticide residues in meat and eggs may be a potential human health hazard, no tolerance level has as yet been set by the Food and Drug Administration. The objective of this investigation was to determine the effect of management practices on the depletion of DDT residues in the abdominal fat and egg yolks of commercial layers following a measured exposure to the insecticide.
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and fatty acid composition of the chicken. J. Nutrition, 75: 157-164. Marion, J. E., and H. M. Edwards, Jr., 1963. The effect of age on the response of chickens to dietary protein and fat. J. Nutrition, 79: 53-61. Marion, J. E., and J. G. Woodroof, 1963. The fatty acid composition of breast, thigh and skin tissues of chicken broilers as influenced by dietary fats. Poultry Sci. 42: 1202-1207. Miller, E. C , H. Menge and C. A. Denton, 1962. Effect of dietary fat on tissue fat and plasma cholesterol level in broilers. Poultry Sci. 4 1 : 970-974. Pope, D. L., 1960. Nutrition and environmental temperature studies with broilers. Proc. Univ. Maryland Nutr. Conf. Feed Mfg. 48-53. Reiser, R., 1950. The metabolism of polyunsaturated fatty acids in growing chicks. J. Nutrition, 42: 325-330.
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