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The Influence of Intestinal (Ceca) Flora on Serum and Egg Yolk Cholesterol Levels in Laying Hens
1935
DWARF BREEDER ENERGY NEEDS
hens in a meat-type strain of domestic fowl. World's Poultry Sci. J. 27: 292. Steel, R. G. D., and J. H. Torrie, 1960. Principles and Procedures of Statistics. McGraw Hill Co., New York, N.Y. Summers, J. D., 1971. Nutrition of the dwarf layer. World's Poultry Sci. J. 27: 287. vanTienhoven, A., J. H.Williamson, M.C. Tomlinson and K. L. Maclnnes, 1966. Possible role of the thyroid and pituitary glands in sex-linked dwarfism in the fowl. Endocrinology, 78: 950-957. Waldroup, P. W., B. L. Damron and R. H. Harms, 1966. Effect of low protein and high fiber grower diets on the performance of broiler pullets. Poultry Sci. 45: 393-402.
The Influence of Intestinal (Ceca) Flora on Serum and Egg Yolk Cholesterol Levels in Laying Hens F . TORTUERO, A . BRENES AND J . RlOPEREZ
Institute) de Alimentation y Productividad Animal, C.S.I.C.- Ciudad Universitaria, Madrid -3, Spain (Received for publication March 4, 1975)
ABSTRACT Normal and cecectomized laying hens were used to study the influence of intestinal (ceca) flora and the implantation of Lactobacillus acidophylus on the levels of serum and egg yolk cholesterol. The ceca had been surgically removed when the experimental birds were 16 months of age. Serum cholesterol levels of cecectomized laying hens were higher than that of normal birds; the Lactobacillus acidophylus implantation resulted in a significant decrease in serum cholesterol levels in both normal and cecectomized birds. The normal intestinal (ceca) flora and Lactobacillus acidophylus implantation did not influence fat digestibility. Egg yolk cholesterol levels were higher for cecectomized birds. A constant relationship between serum and egg yolk cholesterol was not observed. POULTRY SCIENCE 54: 1935-1938, 1975
INTRODUCTION
I
the
degree
of
hypercholesterolemia
and
T has been nearly 50 years since physicians
coronary atherosclerosis. However, this cor-
first linked serum cholesterol with heart
relation is not always observed in laying hens
disease. The facts are that cholesterol is only one of the factors that contribute to atheromatosis. It is true that atherogenesis, plasma lipids
(Kurnick, 1958). On the other hand, individual chickens exhibit different plasma and egg yolk cholesterol levels, particularly when fed a diet
and cholesterol levels may be affected by
containing cholesterol (March et al., 1964).
dietary constituents. Some workers, such as
Similar differences may also be observed in
Christensen (1964) and Banerjee et al. (1965),
the rates of cholesterol synthesis, absorption
showed an increase in cholesterol of the aorta
and elimination from the body.
of cockerels fed cholesterol and Pick et al.
The role of intestinal microorganisms in
(1967) found a positive relationship between
the cholesterol destruction or degradation in
Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 3, 2015
size and reproduction. World's Poultry Sci. J. 27: 281. Quisenberry, J. H., A. G. Delfino and J. W. Bradley, 1969. Effects of density and dietary protein level on performance of midgets versus normal layers. Poultry Sci. 48: 1861. Rajaratnam, G., T. Selvarajah and J. D. Summers, 1969. The effect of thyroprotein on growth rate of dwarf pullets. Poultry Sci. 48: 1768-1770. Rajaratnam, G., J. D. Summers, A. S. Wood and E. T. Moran, Jr., 1971. Some physiological and nutritional aspects of the dwarf chicken. Can. J. An. Sci. 51: 209-216. Ricard, F. M., and L. P. Cochez, 1971. Effects of the sex-linked dwarf gene, dw, on performance of
1936
F . TORTUERO, A . BRENES AND J . RlOPEREZ
MATERIALS AND METHODS Fifty battery-reared Babcock laying hens, 20 months old, were distributed into five groups of 10 birds each ( N p N 2 , N 3 , C, and C 2). The N , , N 2 and N 3 groups consisted of normal or control birds. At 16 months of age the hens of groups C, and C 2 had been cecectomized, having been previously anesthetized by intravenous injection of sodium pentobarbital. The operating room was well lighted and the temperature about 22° C. All instruments were washed and rinsed in ethyl alcohol. The abdominal area was disinfected with merthiolate and one incision was made at the right side. The vessels of the mesentery and the ceca were than ligated and the ceca removed. Finally, the peritoneum, muscles and skin were sutured and, for a period of four days, oxytetracycline and B-complex vitamins were added to the drinking water. Four months later the cecectomized birds were placed on experiment. All birds, except for those in group N , , were fed a diet with added cholesterol (0.2%). The composition of the experimental diet, relatively high in fat, was as follows (in %): yellow corn 58.15; lard 4.0; soybean meal (44% protein) 22.0; dehydrated alfalfa meal (17% protein) 5.0; dicalcium phosphate 2.6; limestone 7.5; salt 0.35; and vitamin-trace mineral mixture 0.2. The vitamin-trace mineral mix supplied per kg. of feed (mg./kg.):
vitamin A palmitate (325,000 I.U./g.) 3.0; vitamin D 3 (500,000 I.U./g.) 4.0; vitamin B 1 2 0.01; riboflavin 5.0; pantothenic acid 8.0; niacin 28.0; choline chloride 200.0; manganese 60.0; zinc 50.0; copper 4.0; iron 20.0; and iodine 0.5. The diet was fed ad libitum during the experimental period (20 to 23 months of age). One gelatin capsule containing 3 x 106 organisms (Lactobacillus acidophylus) was administered at the first of each month to each bird in groups N 3 and C 2 . Serum samples were collected monthly by heart puncture, the hens having previously fasted for 14 hours. At the end of the experiment six eggs were collected from each group and the yolks were used for cholesterol determination. Serum and yolk cholesterol analyses were made according to the procedure of Zlatkis et al. (1953). After two months on the experiment chromic oxide (0.3%) was added to the diet of all groups to determine the influence of intestinal (ceca) flora and the implantation of Lactobacillus acidophylus on fat digestibility. The determinations were made by acid digestion of the chromic oxide and the Soxhlet method, an analytical procedure for total fat of the feces and feed. The experimental data on serum cholesterol were analyzed by analysis of variance according to Snedecor (1956). RESULTS AND DISCUSSION Data on serum cholesterol levels, at different times of the experiment, are given in Table 1. The cholesterolemia from the first to the third experimental month seems to show a tendency to increase. Nevertheless, it is convenient to advise that much individual variations were obtained in serum cholesterol levels within treatments. These individual bird differences have been previously observed by other workers (March et al., 1964; Edwards and Jones, 1964). On the other hand,
Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 3, 2015
the rat has been reported by Danielsson and Gustafsson (1959). There are indications that the same may be true in the chicken (Kritchesky et al., 1959; Coates et al., 1965). However, there is no specific information in this regard. This study was conducted to determine the influence of ceca microorganisms and the implantation of Lactobacillus acidophylus on serum and egg yolk cholesterol levels in laying hens.
1937
CECA FLORA AND CHOLESTEROL
TABLE 1.—Effect
Groups 2,3 N, N2 N3
Organisms implanted
Cholesterol added (g-/Kg. of feed)
Plasma cholesterol levels' (mg./lOOml.) 20
—
— —
3 x 106
— 3 x 106
81.8 111.0 117.0 146.5 137.0
2.0 2.0 2.0 2.0
Age of the hens (in months) 21 22 111.1 106.5 n.s. 132.0* 158.0 n.s. 87.0 139.0 n.s. 179.9** 167.5** 121.3 143.8
1) Each value is the mean of eight hens. 2) Group N, has not been considered for statistical analysis. 3) The statistical values refer to normal or cecectomized birds fed cholesterol and only within themselves (N2 and N 3 ) (C, and C2) for each month of age separately; (n.s. = not significant; * = P < .05; ** = P < .01). the differences in the cholesterolemia seen between the normal and cecectomized birds (groups N 2 and C , ; N 3 and C 2 , respectively) indicate that the ceca microflora may have some influence on the degradation of cholesterol. It may also be observed that the implantation of Lactobacillus acidophilus (groups N 3 and C 2 ) resulted in a significant decrease in the cholesterolemia. The abovementioned differences confirm the suspicion of Kritchevsky et al. (1959) and Coates et al. (1965). This relationship is similar to the one obtained by Danielsson and Gustafsson (1959) in rats, the differences being in the order of 15 to 20 percent. The role of intestinal flora may be explained as the mechanism of cholesterol degradation which, according to Lofland et al. (1972) in reference to monkeys, is related to the conversion of cholesterol into bile acids. This
fact also applies to birds in which the cholesterol is entirely eliminated with the feces as neutral C-27 steroids and bile acids (Danielsson and Tchen, 1968). The changes in serum cholesterol levels among different groups are not well correlated with fat digestibility. In this respect, the results from Table 2 appear to show no marked differences in fat digestibility. On the other hand, the fat digestibility data, obtained from the groups in which the Lactobacillus acidophylus implantations were made, are in agreement with those reported by Tortuero (1973). The results on egg yolk cholesterol levels are also presented in Table 2. It may be observed that the egg yolk cholesterol levels increased in cecectomized birds, although a constant relationship between serum and egg yolk cholesterol levels has not been satisfac-
TABLE 2.—The influence of intestinal (ceca)floraand Lactobacillus acidophylus implantation in laying hens on fat digestibility and egg yolk cholesterol level
Groups N, N2 N3
c,
C2
Organisms implanted
— — 3 x 106
—
3 x 106
Cholesterol added (g./Kg. of feed)
— 2.0 2.0 2.0 2.0
1) Data are means of yolks of six eggs of similar weight.
Fat digestibility
(%) 95.5 95.7 95.8 95.7 96.1
Egg yolk 1 cholesterol levels (mg./g.) 16.6 16.6 17.2 20.3 20.3
Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 3, 2015
c, c2
of intestinal (ceca) flora and Lactobacillus acidophylus on plasma cholesterol level
1938
F . TORTUERO, A . BRENES AND J . RlOPEREZ
torily elucidated. At the same time, it appears that there is no influence of intestinal (ceca) flora and Lactobacillus acidophylus implantation on egg yolk cholesterol content. ACKNOWLEDGEMENTS
REFERENCES Banerjee, S., P. N. Rao and S. K. Ghosh, 1965. Biochemical and histochemical changes in aorta of chicks fed vegetable oils and cholesterol. Pro. Soc. Exptl. Biol. Med. 119: 1081-1086. Coates, M. E., G. F. Harrison and J. H. Moore, 1965. Cited by Cuthbertson, D. In: The Nutrition of Animals of Agricultural Importance. Oxford-Pergamon, Press, vol. XVII. l«Part. pgs. 253-259. 1969. Christensen, S., 1964. Transfer of labelled cholesterol across the aortic intimal surface of normal and cholesterol fed cockerels. J. Atherosclerosis Res. 4: 151-160. Danielsson, H., and B. Gustafsson, 1959. On serumcholesterol level and neutral fecal sterols in germfree rats. Bile acids and steroids. Arch. Biochem. Biophys. 83: 482-485.
NEWS AND NOTES (Continued from page 1926) SHAVER NOTES
A.H.I. NOTES
Dr. Paul C. Miller has been appointed to the Shaver Poultry Breeding Farms Limited Technical Department. He was previously at the University of Wisconsin, where he was involved in studies concerned with poultry nutrition and its role in environmental interaction during the rearing period.
At the annual meeting of the Animal Health Institute, held in Phoenix, Arizona, the following officers were elected: President—R. M. Hendrickson, Agricultural Division, Pfizer, Inc.; First Vice President—George S. Appleton, Agricultural and Veterinary Division, Abbott Laboratories; Second Vice President—P. G.
(Continued on page 1945)
Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 3, 2015
This work was supported in part by the Instituto de Microbiologia Industrial. We are particularly indebted to Prof. G. Gonzalez, Director of the Instituto de Alimentacion y Productividad Animal, for his assistance, and to Dr. R. Caballero for his help in statistical analysis. In addition, the authors thank Mr. A. Ramos and Mr. J. Picazo for their help in analytical determinations and for the care of the laying hens, respectively.
Danielsson, H., and T. T. Tchen, 1968. Steroid metabolism. In: Metabolic Pathways. Ed. by D. M. Greenberg, Academic Press (3rd ed.). vol. 11: 117168. Edwards, H. M. Jr., and V. Jones, 1964. Effect of dietary cholesterol on serum and egg cholesterol levels over a period of time. Poultry Sc. 43: 877-879. Kritchevsky, D., R. R. Kolman, R. M. Guttmacher and R. Forbes, 1959. Influence of dietary carbohydrate and protein on serum and liver cholesterol in germ-free chickens. Arch. Biochem. Biophys. 85:444-451. Kurnick, A. A., J. B. Sutton, M. V. Pasvogel and A. R. Kemmerer, 1958. Effect of betaine, choline and methionine on the concentration on serum, tissue and egg yolk cholesterol. Poultry Sci. 37: 1218. Lofland, H. B., Jr., T. B. Clarkson, R. W. St. Clair andN. D. M. Lehner, 1972. Studies on the regulation of plasma cholesterol levels in squirrel monkeys of two genotypes. J. Lipid Res. 13: 39-47. March, B. E., J. Biely and O. B. Lindsay, 1964. Fat and cholesterol absorption in relation to blood cholesterol level in the cockerel. Canad. J. Biochem. 42: 121-126. Pick, R., C. Kakita and P. Johnson, 1967. Relationship between plasma cholesterol level and coronary atherosclerosis in cholesterol-fed cockerels. Fed. Proc. 26: 490. Snedecor, G. W., 1956. Statistical Methods. The Iowa State University Press, Ames, Iowa. Tortuero, F., 1973. Influence of the implantation of Lactobacillus acidophylus in chicks on the growth, feed conversion, malabsorption of fat syndrome and intestinal flora. Poultry Sci. 52: 197-203. Zlatkis, A., B. Zar and A. J. Boyle, 1953. A new method for the direct determination of serum cholesterol. J. Lab. Clin. Med. 41: 486-487.
DWARF BREEDER ENERGY NEEDS
hens in a meat-type strain of domestic fowl. World's Poultry Sci. J. 27: 292. Steel, R. G. D., and J. H. Torrie, 1960. Principles and Procedures of Statistics. McGraw Hill Co., New York, N.Y. Summers, J. D., 1971. Nutrition of the dwarf layer. World's Poultry Sci. J. 27: 287. vanTienhoven, A., J. H.Williamson, M.C. Tomlinson and K. L. Maclnnes, 1966. Possible role of the thyroid and pituitary glands in sex-linked dwarfism in the fowl. Endocrinology, 78: 950-957. Waldroup, P. W., B. L. Damron and R. H. Harms, 1966. Effect of low protein and high fiber grower diets on the performance of broiler pullets. Poultry Sci. 45: 393-402.
The Influence of Intestinal (Ceca) Flora on Serum and Egg Yolk Cholesterol Levels in Laying Hens F . TORTUERO, A . BRENES AND J . RlOPEREZ
Institute) de Alimentation y Productividad Animal, C.S.I.C.- Ciudad Universitaria, Madrid -3, Spain (Received for publication March 4, 1975)
ABSTRACT Normal and cecectomized laying hens were used to study the influence of intestinal (ceca) flora and the implantation of Lactobacillus acidophylus on the levels of serum and egg yolk cholesterol. The ceca had been surgically removed when the experimental birds were 16 months of age. Serum cholesterol levels of cecectomized laying hens were higher than that of normal birds; the Lactobacillus acidophylus implantation resulted in a significant decrease in serum cholesterol levels in both normal and cecectomized birds. The normal intestinal (ceca) flora and Lactobacillus acidophylus implantation did not influence fat digestibility. Egg yolk cholesterol levels were higher for cecectomized birds. A constant relationship between serum and egg yolk cholesterol was not observed. POULTRY SCIENCE 54: 1935-1938, 1975
INTRODUCTION
I
the
degree
of
hypercholesterolemia
and
T has been nearly 50 years since physicians
coronary atherosclerosis. However, this cor-
first linked serum cholesterol with heart
relation is not always observed in laying hens
disease. The facts are that cholesterol is only one of the factors that contribute to atheromatosis. It is true that atherogenesis, plasma lipids
(Kurnick, 1958). On the other hand, individual chickens exhibit different plasma and egg yolk cholesterol levels, particularly when fed a diet
and cholesterol levels may be affected by
containing cholesterol (March et al., 1964).
dietary constituents. Some workers, such as
Similar differences may also be observed in
Christensen (1964) and Banerjee et al. (1965),
the rates of cholesterol synthesis, absorption
showed an increase in cholesterol of the aorta
and elimination from the body.
of cockerels fed cholesterol and Pick et al.
The role of intestinal microorganisms in
(1967) found a positive relationship between
the cholesterol destruction or degradation in
Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 3, 2015
size and reproduction. World's Poultry Sci. J. 27: 281. Quisenberry, J. H., A. G. Delfino and J. W. Bradley, 1969. Effects of density and dietary protein level on performance of midgets versus normal layers. Poultry Sci. 48: 1861. Rajaratnam, G., T. Selvarajah and J. D. Summers, 1969. The effect of thyroprotein on growth rate of dwarf pullets. Poultry Sci. 48: 1768-1770. Rajaratnam, G., J. D. Summers, A. S. Wood and E. T. Moran, Jr., 1971. Some physiological and nutritional aspects of the dwarf chicken. Can. J. An. Sci. 51: 209-216. Ricard, F. M., and L. P. Cochez, 1971. Effects of the sex-linked dwarf gene, dw, on performance of
1936
F . TORTUERO, A . BRENES AND J . RlOPEREZ
MATERIALS AND METHODS Fifty battery-reared Babcock laying hens, 20 months old, were distributed into five groups of 10 birds each ( N p N 2 , N 3 , C, and C 2). The N , , N 2 and N 3 groups consisted of normal or control birds. At 16 months of age the hens of groups C, and C 2 had been cecectomized, having been previously anesthetized by intravenous injection of sodium pentobarbital. The operating room was well lighted and the temperature about 22° C. All instruments were washed and rinsed in ethyl alcohol. The abdominal area was disinfected with merthiolate and one incision was made at the right side. The vessels of the mesentery and the ceca were than ligated and the ceca removed. Finally, the peritoneum, muscles and skin were sutured and, for a period of four days, oxytetracycline and B-complex vitamins were added to the drinking water. Four months later the cecectomized birds were placed on experiment. All birds, except for those in group N , , were fed a diet with added cholesterol (0.2%). The composition of the experimental diet, relatively high in fat, was as follows (in %): yellow corn 58.15; lard 4.0; soybean meal (44% protein) 22.0; dehydrated alfalfa meal (17% protein) 5.0; dicalcium phosphate 2.6; limestone 7.5; salt 0.35; and vitamin-trace mineral mixture 0.2. The vitamin-trace mineral mix supplied per kg. of feed (mg./kg.):
vitamin A palmitate (325,000 I.U./g.) 3.0; vitamin D 3 (500,000 I.U./g.) 4.0; vitamin B 1 2 0.01; riboflavin 5.0; pantothenic acid 8.0; niacin 28.0; choline chloride 200.0; manganese 60.0; zinc 50.0; copper 4.0; iron 20.0; and iodine 0.5. The diet was fed ad libitum during the experimental period (20 to 23 months of age). One gelatin capsule containing 3 x 106 organisms (Lactobacillus acidophylus) was administered at the first of each month to each bird in groups N 3 and C 2 . Serum samples were collected monthly by heart puncture, the hens having previously fasted for 14 hours. At the end of the experiment six eggs were collected from each group and the yolks were used for cholesterol determination. Serum and yolk cholesterol analyses were made according to the procedure of Zlatkis et al. (1953). After two months on the experiment chromic oxide (0.3%) was added to the diet of all groups to determine the influence of intestinal (ceca) flora and the implantation of Lactobacillus acidophylus on fat digestibility. The determinations were made by acid digestion of the chromic oxide and the Soxhlet method, an analytical procedure for total fat of the feces and feed. The experimental data on serum cholesterol were analyzed by analysis of variance according to Snedecor (1956). RESULTS AND DISCUSSION Data on serum cholesterol levels, at different times of the experiment, are given in Table 1. The cholesterolemia from the first to the third experimental month seems to show a tendency to increase. Nevertheless, it is convenient to advise that much individual variations were obtained in serum cholesterol levels within treatments. These individual bird differences have been previously observed by other workers (March et al., 1964; Edwards and Jones, 1964). On the other hand,
Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 3, 2015
the rat has been reported by Danielsson and Gustafsson (1959). There are indications that the same may be true in the chicken (Kritchesky et al., 1959; Coates et al., 1965). However, there is no specific information in this regard. This study was conducted to determine the influence of ceca microorganisms and the implantation of Lactobacillus acidophylus on serum and egg yolk cholesterol levels in laying hens.
1937
CECA FLORA AND CHOLESTEROL
TABLE 1.—Effect
Groups 2,3 N, N2 N3
Organisms implanted
Cholesterol added (g-/Kg. of feed)
Plasma cholesterol levels' (mg./lOOml.) 20
—
— —
3 x 106
— 3 x 106
81.8 111.0 117.0 146.5 137.0
2.0 2.0 2.0 2.0
Age of the hens (in months) 21 22 111.1 106.5 n.s. 132.0* 158.0 n.s. 87.0 139.0 n.s. 179.9** 167.5** 121.3 143.8
1) Each value is the mean of eight hens. 2) Group N, has not been considered for statistical analysis. 3) The statistical values refer to normal or cecectomized birds fed cholesterol and only within themselves (N2 and N 3 ) (C, and C2) for each month of age separately; (n.s. = not significant; * = P < .05; ** = P < .01). the differences in the cholesterolemia seen between the normal and cecectomized birds (groups N 2 and C , ; N 3 and C 2 , respectively) indicate that the ceca microflora may have some influence on the degradation of cholesterol. It may also be observed that the implantation of Lactobacillus acidophilus (groups N 3 and C 2 ) resulted in a significant decrease in the cholesterolemia. The abovementioned differences confirm the suspicion of Kritchevsky et al. (1959) and Coates et al. (1965). This relationship is similar to the one obtained by Danielsson and Gustafsson (1959) in rats, the differences being in the order of 15 to 20 percent. The role of intestinal flora may be explained as the mechanism of cholesterol degradation which, according to Lofland et al. (1972) in reference to monkeys, is related to the conversion of cholesterol into bile acids. This
fact also applies to birds in which the cholesterol is entirely eliminated with the feces as neutral C-27 steroids and bile acids (Danielsson and Tchen, 1968). The changes in serum cholesterol levels among different groups are not well correlated with fat digestibility. In this respect, the results from Table 2 appear to show no marked differences in fat digestibility. On the other hand, the fat digestibility data, obtained from the groups in which the Lactobacillus acidophylus implantations were made, are in agreement with those reported by Tortuero (1973). The results on egg yolk cholesterol levels are also presented in Table 2. It may be observed that the egg yolk cholesterol levels increased in cecectomized birds, although a constant relationship between serum and egg yolk cholesterol levels has not been satisfac-
TABLE 2.—The influence of intestinal (ceca)floraand Lactobacillus acidophylus implantation in laying hens on fat digestibility and egg yolk cholesterol level
Groups N, N2 N3
c,
C2
Organisms implanted
— — 3 x 106
—
3 x 106
Cholesterol added (g./Kg. of feed)
— 2.0 2.0 2.0 2.0
1) Data are means of yolks of six eggs of similar weight.
Fat digestibility
(%) 95.5 95.7 95.8 95.7 96.1
Egg yolk 1 cholesterol levels (mg./g.) 16.6 16.6 17.2 20.3 20.3
Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 3, 2015
c, c2
of intestinal (ceca) flora and Lactobacillus acidophylus on plasma cholesterol level
1938
F . TORTUERO, A . BRENES AND J . RlOPEREZ
torily elucidated. At the same time, it appears that there is no influence of intestinal (ceca) flora and Lactobacillus acidophylus implantation on egg yolk cholesterol content. ACKNOWLEDGEMENTS
REFERENCES Banerjee, S., P. N. Rao and S. K. Ghosh, 1965. Biochemical and histochemical changes in aorta of chicks fed vegetable oils and cholesterol. Pro. Soc. Exptl. Biol. Med. 119: 1081-1086. Coates, M. E., G. F. Harrison and J. H. Moore, 1965. Cited by Cuthbertson, D. In: The Nutrition of Animals of Agricultural Importance. Oxford-Pergamon, Press, vol. XVII. l«Part. pgs. 253-259. 1969. Christensen, S., 1964. Transfer of labelled cholesterol across the aortic intimal surface of normal and cholesterol fed cockerels. J. Atherosclerosis Res. 4: 151-160. Danielsson, H., and B. Gustafsson, 1959. On serumcholesterol level and neutral fecal sterols in germfree rats. Bile acids and steroids. Arch. Biochem. Biophys. 83: 482-485.
NEWS AND NOTES (Continued from page 1926) SHAVER NOTES
A.H.I. NOTES
Dr. Paul C. Miller has been appointed to the Shaver Poultry Breeding Farms Limited Technical Department. He was previously at the University of Wisconsin, where he was involved in studies concerned with poultry nutrition and its role in environmental interaction during the rearing period.
At the annual meeting of the Animal Health Institute, held in Phoenix, Arizona, the following officers were elected: President—R. M. Hendrickson, Agricultural Division, Pfizer, Inc.; First Vice President—George S. Appleton, Agricultural and Veterinary Division, Abbott Laboratories; Second Vice President—P. G.
(Continued on page 1945)
Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 3, 2015
This work was supported in part by the Instituto de Microbiologia Industrial. We are particularly indebted to Prof. G. Gonzalez, Director of the Instituto de Alimentacion y Productividad Animal, for his assistance, and to Dr. R. Caballero for his help in statistical analysis. In addition, the authors thank Mr. A. Ramos and Mr. J. Picazo for their help in analytical determinations and for the care of the laying hens, respectively.
Danielsson, H., and T. T. Tchen, 1968. Steroid metabolism. In: Metabolic Pathways. Ed. by D. M. Greenberg, Academic Press (3rd ed.). vol. 11: 117168. Edwards, H. M. Jr., and V. Jones, 1964. Effect of dietary cholesterol on serum and egg cholesterol levels over a period of time. Poultry Sc. 43: 877-879. Kritchevsky, D., R. R. Kolman, R. M. Guttmacher and R. Forbes, 1959. Influence of dietary carbohydrate and protein on serum and liver cholesterol in germ-free chickens. Arch. Biochem. Biophys. 85:444-451. Kurnick, A. A., J. B. Sutton, M. V. Pasvogel and A. R. Kemmerer, 1958. Effect of betaine, choline and methionine on the concentration on serum, tissue and egg yolk cholesterol. Poultry Sci. 37: 1218. Lofland, H. B., Jr., T. B. Clarkson, R. W. St. Clair andN. D. M. Lehner, 1972. Studies on the regulation of plasma cholesterol levels in squirrel monkeys of two genotypes. J. Lipid Res. 13: 39-47. March, B. E., J. Biely and O. B. Lindsay, 1964. Fat and cholesterol absorption in relation to blood cholesterol level in the cockerel. Canad. J. Biochem. 42: 121-126. Pick, R., C. Kakita and P. Johnson, 1967. Relationship between plasma cholesterol level and coronary atherosclerosis in cholesterol-fed cockerels. Fed. Proc. 26: 490. Snedecor, G. W., 1956. Statistical Methods. The Iowa State University Press, Ames, Iowa. Tortuero, F., 1973. Influence of the implantation of Lactobacillus acidophylus in chicks on the growth, feed conversion, malabsorption of fat syndrome and intestinal flora. Poultry Sci. 52: 197-203. Zlatkis, A., B. Zar and A. J. Boyle, 1953. A new method for the direct determination of serum cholesterol. J. Lab. Clin. Med. 41: 486-487.