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Observations on Certain Shell Variations of Hens’ Eggs
459
RESEARCH NOTES TABLE 1.—Effect of dietkylstilbestrol on fat deposition in turkeys (Birds 154 to 228 days of age at autopsy.)
Sex
Length of treatment
Birds
Stilbestrol absorbed
Treated
9
Weight of abdominal adipose tissue
Dressed weight Control
Treated
Control
days 30 44 90
no. 6 8 3
mg. 24.7 29.1 41.0
kilos 7.40 6.79 6.76
kilos 7.38 6.28 7.52 "
gm. 93.9 119.4 176.4
gm. 43.2 30.7 111.0
30 44 90
10 5 1
18.3 22.3 46.3
4.80 4.13 4.48
4.42 3.98 4.06
79.1 115.4 212.8
47.0 28.5 104.0
trols', however, and this difference was statistically significant. F. W. LORENZ Division of Poultry Husbandry University of California Davis Received for publication July 10, 1944
REFERENCES
Lorenz, F. W., 1943. Fattening cockerels by stilbestrol administration. Poultry Sci. 22, 190191. -, In press. The influence of diethylstilbestrol on fat deposition and meat quality in chicks.
OBSERVATIONS ON CERTAIN SHELL VARIATIONS OF HENS' EGGS Several interesting variations of egg shells have been produced by a small backyard flock of hens during the past year. The birds are crossbred from Barred P.R. cock with R.I. Red hens, and have been maintained under the ordinary type of conditions, with very good production records. In rubbing off a little dirt from one egg, it was found that the brown pigment came off also. In fact, when rubbed more vigorously with a damp handkerchief, it yielded almost all its color and was made nearly white. This surprising discovery led to further rubbing tests and observations. These showed that most of the eggs would give up some pigment when rubbed, but some, especially those with a somewhat glossy surface, were very tenacious of their color. On the other hand, a few lost the pigment so readily that they were already partially "wiped" when found in the nest.
A second type of variation was a chalky white finish on a few eggs. In some cases the whole egg was so covered; in others, the coating was not uniform, some areas of the brown shell being bare. The chalky coat could be scraped off in any area to reveal the normal shell color underneath. A peculiar egg shape was found repeatedly; one side of the shell was flattened, usually with a ring of slight corrugations around this area. Otherwise these eggs seemed normal, though often a bit small. We have been unable to find any literature commenting directly on these variations (cf. Hall, 1944). The physiology or pathology of the oviduct involved in such conditions would seem to be of considerable significance as well as interest. A few questions and speculations are here raised. First, is the condition of easily removable, superficial pigmentation of wide oc-
460
RESEARCH
NOTES
FIG. 1. Blown eggs demonstrating three types of shell variation. A is an egg as found in the nest, with areas of depigmentation. B, C, and D have been rubbed, and show differences in ease of removing color. The next row shows eggs variously coated with a chalky deposit; G has been scraped. The lower row shows shell deformations.
currence? It seems to be a spontaneous separation of the processes of lime and pigment secretion. Second, is the chalky coating found on some eggs due to retention of the egg in the oviduct some hours after the proper time for laying? It should
be noted that at least some of these eggs were laid by the hens at night, from the roost. It seems plausible to assume that additional calcium carbonate would be deposited on a finished egg if it were not laid promptly. Third, what could be the
461
RESEARCH NOTES
cause of the flattened egg shapes? Was there some pressure from crowding of the hen's internal organs in some way, or was one side of the shell-secreting region of the oviduct defective? At any rate, these shapes seem good evidence that rotation of the egg does not occur during shell formation, as suggested by some oologists. If such peculiarities are as common as indicated by their frequency in this small flock, a more extensive study of them in large populations and with laboratory
methods should yield very interesting information. MORRIS STEGGERDA W. F. HOLLANDER Department of Genetics Carnegie Institution of Washington Cold Spring Harbor, New York Received for publication July 27, 1944. REFERENCE
Hall, G. O. 1944. Egg shell color in crosses between white- and brown-egg breeds. Poultry Sci. 23:259-265.
VARIATION IN THE GROWTH-RATE OF EXPERIMENTAL BIRDS One of the difficulties with which the small, tends to obscure the effect on growth experimenter, who is conducting poultry by the ration under study and renders it feeding trials, must contend, is the great difficult to satisfactorily interpret the results of the experiment. Under such cirTABLE 1.—Ration composition cumstances, even the application of a statistical analysis to the data is not entirely Ration Ration Ingredient B satisfactory, and the investigator, if he A is to draw reliable conclusions from his ex20.00 15.00 Ground yellow corn 10.00 10.00 periments must minimize the influence of Wheat bran 10.00 5.00 Wheat shorts this variation by the use of a large number 10.00 10.00 Ground wheat 10.00 5.00 Rolled oat groats of birds per group. 10.00 12.00 Ground whole oats As pointed out by Schroeder and Law2.25 19.80 Ground barley 3.00 4.00 Dehydrated alfalfa rence (1943) the use of a sufficiently large 1.00 Cereal grass number of birds to permit the accurate' 2.50 Fish meal (65%) 5.00 3.00 Meat meal (50%) interpretation of results is a factor which 7.00 8.00 Soybean oil meal is too often disregarded in feeding trials. 5.00 2.00 Buttermilk powder 2.50 3.50 Oyster shell (fine) Undoubtedly, many of the failures to dupli0.50 0.50 Salt (iodized and manganized) cate the results of an experiment may be 1.00 1.00 Grit (insol.) 0.20 0.25 Cod liver oil (400 D 3000 A) traced to this factor, particularly if the 1.00 Steamed bone meal differences in growth due to the influence Totals 100.00 100.00 of the rations under study are relatively small. Crude protein percent 19.5 16.5 1200 Riboflavin (micrograms per lb.) 1670 Some data relating to this problem have been accumulated in the authors' laboravariability in growth exhibited by birds fed tory. While the data are not extensive they the same ration and reared, as far as pos- do illustrate very clearly the importance sible, under identical conditions. This diffi- of the above considerations, and are, thereculty, especially if the group sizes are fore, considered to be of sufficient interest
RESEARCH NOTES TABLE 1.—Effect of dietkylstilbestrol on fat deposition in turkeys (Birds 154 to 228 days of age at autopsy.)
Sex
Length of treatment
Birds
Stilbestrol absorbed
Treated
9
Weight of abdominal adipose tissue
Dressed weight Control
Treated
Control
days 30 44 90
no. 6 8 3
mg. 24.7 29.1 41.0
kilos 7.40 6.79 6.76
kilos 7.38 6.28 7.52 "
gm. 93.9 119.4 176.4
gm. 43.2 30.7 111.0
30 44 90
10 5 1
18.3 22.3 46.3
4.80 4.13 4.48
4.42 3.98 4.06
79.1 115.4 212.8
47.0 28.5 104.0
trols', however, and this difference was statistically significant. F. W. LORENZ Division of Poultry Husbandry University of California Davis Received for publication July 10, 1944
REFERENCES
Lorenz, F. W., 1943. Fattening cockerels by stilbestrol administration. Poultry Sci. 22, 190191. -, In press. The influence of diethylstilbestrol on fat deposition and meat quality in chicks.
OBSERVATIONS ON CERTAIN SHELL VARIATIONS OF HENS' EGGS Several interesting variations of egg shells have been produced by a small backyard flock of hens during the past year. The birds are crossbred from Barred P.R. cock with R.I. Red hens, and have been maintained under the ordinary type of conditions, with very good production records. In rubbing off a little dirt from one egg, it was found that the brown pigment came off also. In fact, when rubbed more vigorously with a damp handkerchief, it yielded almost all its color and was made nearly white. This surprising discovery led to further rubbing tests and observations. These showed that most of the eggs would give up some pigment when rubbed, but some, especially those with a somewhat glossy surface, were very tenacious of their color. On the other hand, a few lost the pigment so readily that they were already partially "wiped" when found in the nest.
A second type of variation was a chalky white finish on a few eggs. In some cases the whole egg was so covered; in others, the coating was not uniform, some areas of the brown shell being bare. The chalky coat could be scraped off in any area to reveal the normal shell color underneath. A peculiar egg shape was found repeatedly; one side of the shell was flattened, usually with a ring of slight corrugations around this area. Otherwise these eggs seemed normal, though often a bit small. We have been unable to find any literature commenting directly on these variations (cf. Hall, 1944). The physiology or pathology of the oviduct involved in such conditions would seem to be of considerable significance as well as interest. A few questions and speculations are here raised. First, is the condition of easily removable, superficial pigmentation of wide oc-
460
RESEARCH
NOTES
FIG. 1. Blown eggs demonstrating three types of shell variation. A is an egg as found in the nest, with areas of depigmentation. B, C, and D have been rubbed, and show differences in ease of removing color. The next row shows eggs variously coated with a chalky deposit; G has been scraped. The lower row shows shell deformations.
currence? It seems to be a spontaneous separation of the processes of lime and pigment secretion. Second, is the chalky coating found on some eggs due to retention of the egg in the oviduct some hours after the proper time for laying? It should
be noted that at least some of these eggs were laid by the hens at night, from the roost. It seems plausible to assume that additional calcium carbonate would be deposited on a finished egg if it were not laid promptly. Third, what could be the
461
RESEARCH NOTES
cause of the flattened egg shapes? Was there some pressure from crowding of the hen's internal organs in some way, or was one side of the shell-secreting region of the oviduct defective? At any rate, these shapes seem good evidence that rotation of the egg does not occur during shell formation, as suggested by some oologists. If such peculiarities are as common as indicated by their frequency in this small flock, a more extensive study of them in large populations and with laboratory
methods should yield very interesting information. MORRIS STEGGERDA W. F. HOLLANDER Department of Genetics Carnegie Institution of Washington Cold Spring Harbor, New York Received for publication July 27, 1944. REFERENCE
Hall, G. O. 1944. Egg shell color in crosses between white- and brown-egg breeds. Poultry Sci. 23:259-265.
VARIATION IN THE GROWTH-RATE OF EXPERIMENTAL BIRDS One of the difficulties with which the small, tends to obscure the effect on growth experimenter, who is conducting poultry by the ration under study and renders it feeding trials, must contend, is the great difficult to satisfactorily interpret the results of the experiment. Under such cirTABLE 1.—Ration composition cumstances, even the application of a statistical analysis to the data is not entirely Ration Ration Ingredient B satisfactory, and the investigator, if he A is to draw reliable conclusions from his ex20.00 15.00 Ground yellow corn 10.00 10.00 periments must minimize the influence of Wheat bran 10.00 5.00 Wheat shorts this variation by the use of a large number 10.00 10.00 Ground wheat 10.00 5.00 Rolled oat groats of birds per group. 10.00 12.00 Ground whole oats As pointed out by Schroeder and Law2.25 19.80 Ground barley 3.00 4.00 Dehydrated alfalfa rence (1943) the use of a sufficiently large 1.00 Cereal grass number of birds to permit the accurate' 2.50 Fish meal (65%) 5.00 3.00 Meat meal (50%) interpretation of results is a factor which 7.00 8.00 Soybean oil meal is too often disregarded in feeding trials. 5.00 2.00 Buttermilk powder 2.50 3.50 Oyster shell (fine) Undoubtedly, many of the failures to dupli0.50 0.50 Salt (iodized and manganized) cate the results of an experiment may be 1.00 1.00 Grit (insol.) 0.20 0.25 Cod liver oil (400 D 3000 A) traced to this factor, particularly if the 1.00 Steamed bone meal differences in growth due to the influence Totals 100.00 100.00 of the rations under study are relatively small. Crude protein percent 19.5 16.5 1200 Riboflavin (micrograms per lb.) 1670 Some data relating to this problem have been accumulated in the authors' laboravariability in growth exhibited by birds fed tory. While the data are not extensive they the same ration and reared, as far as pos- do illustrate very clearly the importance sible, under identical conditions. This diffi- of the above considerations, and are, thereculty, especially if the group sizes are fore, considered to be of sufficient interest