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Additional Data on Effect of Castration in Domestic Fowl
wattles, began to grow after eighteen months of age, eventually reaching a large size. These birds crow and exhibit sexual reactions. Castrated drakes, too, develop the plumage of the normal male. Those castrated completely possess one peculiarity; however, in that they do not assume the summer plumage but, although moulting frequently, always retain the so-called breeding plumage. On the other hand, the female whether duck or fowl, from which the ovaries have been completely removed always develop male characters in large measure though the degree to which these charactsars develop varies somewhat. In some individuals of each species the assumption of the male plumage has been practically complete. The castrated pullets look very much like capons, but have short legs. Sometimes, however, the comb and wattles become relatively large. The reason for this, perhaps, is to be found in a compensatory hypertrophy of the Wolfian body and duct observed in one instance, which seem to persist in some normal females for some months at least. It is quite posssible too that the comb and wattles of the male owe their development not so much to the sperrmatogenetic tissue as to the epididymis. In ducks, after the removal of the ovary, the plumage sometimes becomes exactly like that of the male. However, in no instance has it been observed that the color of the upper mandible became like that of the drake, nor has a duck been observed which developed the male's voice, though in some instances they are unable to produce a normal "quack." In some instances, too, the castrated ducks develop the summer plumage. There is, however, a class of females which after castration do not develop typical male plumage but acquire a distinctive type which is made up of numerous feathers of the male breeding plumage type and a second type bearing a close resemblance to the feathers of the male's summer plumage. In some sections, these last are often like those of the female. These females are undoubtedly constitutionally different from the others. Thus far, all pure bred females have belonged to the types just described, while those females which develop the most perfect male plumage have always been hybrids.
merely small spots or stripes on an otherwise pure white feather. It appears then from an analysis of the F l generation that in so far as the characters of eye color, beak color, and shank color are concerned that there is a sex limitation to the mode of inheritance. This apparent sex linking is also observed in the prevalence of black feathers in the female progeny. The results of the work to date will however warrant two general conclusions. The Black Langshan is essentially a pigmented bird, showing evidences of such pigmentation in eye, beak, shank and plumage color; while on the other hand the Leghorn is essentially a non-pigmented bird. Appreciating this difference we may safely say that this pigmentation is sex limited in its mode of inheritance only when the male parent possesses this factor; in which case so far as its inheritance in the first generation is concerned, it behaves similar to a dominant character. 2nd. White Leghorns carry without doubt, a factor for barring5. Observations tend to point to the fact that the factor which inhibits the appearance of the barring (if such a factor is used to explain the non-appearance of the barring) varies in intensity in different individuals and may vary in the same individual at different times. The cause for this! variation being at present undetermined.— H. R. LEWIS. NOTE.—For a more complete account, including photo illustrations, see Annual Report N. J. Agricultural Experiment Station, 1913.
ADDITIONAL DATA ON EFFECT OF CASTRATION IN DOMESTIC FOWL. It has been shown that orchidotomy does not cause the male bird to assume any female characters but causes him to retain certain juvenile characters for a time. On the other hand, ovariotomy results in the assumption of male characters by the operated female. Additional data resulting from operations on twenty-six females and numerous males is now available. Owing to the briefness of the abstract, it will be impossible to give the history of individual cases. The general results only can be reported. Castration of the male brings about comparatively small changes in the secondary sexual characters. A capon is externally like the male, except that the comb and wattles remain small for a long time. Moreover, they do not as a rule crow or tread the hens. However, in some capons kept for a number of years, the comb and
In a number of instances the complete removal of the ovary has not been effected, but minute portions remained behind. In these instances the new feathers which developed immediately after the operation were like those of the male, but those which developed still later were female. Many were partly male and partly female. The male portion in some instances being separated by a clear-cut transverse line from the female part. A regenerated ovary has been found in all such instances. In birds which were moulting when completely ovariotom-
5 Cf. Hadley, Davenport, loc, cit.
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ized the partly grown feathers exhibited the first sign of male characters about ten days after the operation, so that it seems probable that the change in the mode of development must take place almost immediately. It is of some interest to compare the results of castration in birds with those of other animals. Meisenheimer and others have shown in insects that the gonads have no effect whatever on the secondary sexual characters. In mammals it is known that castration causes certain characters of the male to remain in a juvenile condition, while in the female relatively little effect is produced. In certain Crustacea Smith found that the male assumed female characters as a result of parasitic castration. We may conclude, therefore, that while both the ovaries and testes produce internal secretions, their effect is quite different, that of the ovary being the most striking in that it is responsible for development of the female secondary sexual characters. Possibly, as a working hypothesis for birds, we may assume that the secondary sexual characters of the male, subject of course to the above observations on the comb, wattles and crowing instinct are common to each sex, but are modified in the female, under the influence of the ovary, Into her characters. Hence, after castration the male characters develop while in the male no .comparable change takes place. It is possible to show that the mechanism of inheritance of the internal secretions may follow a sex limited method of descent, but this will not be gone into here.— H. D. GOODALE.
THE
VALUE OF SOUR MILK FOR FEEDING LITTLE CHICKS. The value of sour milk for feeding little chicks seems to come from the actual food value in the milk rather than from the development of acid in souring as has been very commonly supposed. This evidence is quite plainly brought out by the following experiments: To prove the value of acid, experiments were conducted to compare sour milk containing 1% acid, Bulgaricus milk containing I to 2% acid and sweet milk containing no acid, all of these were conducted with check lots getting no milk. In all experiments records were kept showing mortality and gain of chicks, grain consumed and milk consumed. The chicks and grain were weighed each week. The milk was weighed out and what remained weighed back twice or three times each :day. The results were not in accordance with the claims made for Bulgaricus milk of high acid content. In fact it made little difference whether the milk was allowed to develop 2% acid or fed when it contained half that amount. In comparison with ordinary sour milk, the chickens did not seem to like it as well, ate less and
made smaller gains per pound of milk consumed. Sweet milk gave slightly better results than Bulgaricus milk but not equal to ordinary sour milk. In figuring the money value of sour milk for chickens, we have taken our estimates from the difference in growth between those having sour milk and those having no milk. The figures are taken from eight different experiments conducted over a period of two years, including chickens from three different breeds. _ It was very evident from our observation that milk was worth more the first few days than later on in the life of a chicken, consequently values were worked out by weeks. In converting the milk consumed to a money value, the grain eaten by each lot was figured at 2% cents per pound and the extra gains made by the sour milk pens were credited to the sour milk in terms of money value based on the cost of grain that would have been consumed to produce the same gains without milk. This method of figuring gives the following results : 1st week 4.7 cts. per qt. 2d week 3.6 cts. per qt. 3rd week 2.5 cts. per qt. 4th week 1.4 cts. per qt. 5th week 2.3 cts. per qt. 6th week 1.5 cts. per qt. Average for six weeks 2.5 cents per quart. It will be noted that the lowest value of milk comes in the fourth week with quite a noticeable increase on the fifth week. This we cannot seem to account for except through the fact that milk does not contain the particular protein which _ is necessary for feather growth. Aside from the increased growth which sour milk gives a chicken it has a marked influence on the vigor and vitality of the bird.—ROY JONES.
THE POULTRY DEPARTMENTS. Mr. H. E. Eswine of the Extension Department of the Ohio State University, has charge of the Poultry Educational exhibit which is being staged at the most prominent shows in Ohio. Mr. C. L. Long, formerly in charge of Poultrv Instruction in Extension School of Ohio State Universitv, has resigned to accept the position of Extension Lecturer in Horticulture at the New Hampshire State Agricultural College. The Poultry Departments of Cornell Universitv, Connecticut Agricultural College and New Jersey^ State College of Agriculture are cooperating in the conducting of an extensive educational poultry exhibit and lecture nrogram at the Madison Square Garden Poultry Show which is to be held February twelve to seventeen. The entire Concert hall will be used for educational purposes.
merely small spots or stripes on an otherwise pure white feather. It appears then from an analysis of the F l generation that in so far as the characters of eye color, beak color, and shank color are concerned that there is a sex limitation to the mode of inheritance. This apparent sex linking is also observed in the prevalence of black feathers in the female progeny. The results of the work to date will however warrant two general conclusions. The Black Langshan is essentially a pigmented bird, showing evidences of such pigmentation in eye, beak, shank and plumage color; while on the other hand the Leghorn is essentially a non-pigmented bird. Appreciating this difference we may safely say that this pigmentation is sex limited in its mode of inheritance only when the male parent possesses this factor; in which case so far as its inheritance in the first generation is concerned, it behaves similar to a dominant character. 2nd. White Leghorns carry without doubt, a factor for barring5. Observations tend to point to the fact that the factor which inhibits the appearance of the barring (if such a factor is used to explain the non-appearance of the barring) varies in intensity in different individuals and may vary in the same individual at different times. The cause for this! variation being at present undetermined.— H. R. LEWIS. NOTE.—For a more complete account, including photo illustrations, see Annual Report N. J. Agricultural Experiment Station, 1913.
ADDITIONAL DATA ON EFFECT OF CASTRATION IN DOMESTIC FOWL. It has been shown that orchidotomy does not cause the male bird to assume any female characters but causes him to retain certain juvenile characters for a time. On the other hand, ovariotomy results in the assumption of male characters by the operated female. Additional data resulting from operations on twenty-six females and numerous males is now available. Owing to the briefness of the abstract, it will be impossible to give the history of individual cases. The general results only can be reported. Castration of the male brings about comparatively small changes in the secondary sexual characters. A capon is externally like the male, except that the comb and wattles remain small for a long time. Moreover, they do not as a rule crow or tread the hens. However, in some capons kept for a number of years, the comb and
In a number of instances the complete removal of the ovary has not been effected, but minute portions remained behind. In these instances the new feathers which developed immediately after the operation were like those of the male, but those which developed still later were female. Many were partly male and partly female. The male portion in some instances being separated by a clear-cut transverse line from the female part. A regenerated ovary has been found in all such instances. In birds which were moulting when completely ovariotom-
5 Cf. Hadley, Davenport, loc, cit.
23
ized the partly grown feathers exhibited the first sign of male characters about ten days after the operation, so that it seems probable that the change in the mode of development must take place almost immediately. It is of some interest to compare the results of castration in birds with those of other animals. Meisenheimer and others have shown in insects that the gonads have no effect whatever on the secondary sexual characters. In mammals it is known that castration causes certain characters of the male to remain in a juvenile condition, while in the female relatively little effect is produced. In certain Crustacea Smith found that the male assumed female characters as a result of parasitic castration. We may conclude, therefore, that while both the ovaries and testes produce internal secretions, their effect is quite different, that of the ovary being the most striking in that it is responsible for development of the female secondary sexual characters. Possibly, as a working hypothesis for birds, we may assume that the secondary sexual characters of the male, subject of course to the above observations on the comb, wattles and crowing instinct are common to each sex, but are modified in the female, under the influence of the ovary, Into her characters. Hence, after castration the male characters develop while in the male no .comparable change takes place. It is possible to show that the mechanism of inheritance of the internal secretions may follow a sex limited method of descent, but this will not be gone into here.— H. D. GOODALE.
THE
VALUE OF SOUR MILK FOR FEEDING LITTLE CHICKS. The value of sour milk for feeding little chicks seems to come from the actual food value in the milk rather than from the development of acid in souring as has been very commonly supposed. This evidence is quite plainly brought out by the following experiments: To prove the value of acid, experiments were conducted to compare sour milk containing 1% acid, Bulgaricus milk containing I to 2% acid and sweet milk containing no acid, all of these were conducted with check lots getting no milk. In all experiments records were kept showing mortality and gain of chicks, grain consumed and milk consumed. The chicks and grain were weighed each week. The milk was weighed out and what remained weighed back twice or three times each :day. The results were not in accordance with the claims made for Bulgaricus milk of high acid content. In fact it made little difference whether the milk was allowed to develop 2% acid or fed when it contained half that amount. In comparison with ordinary sour milk, the chickens did not seem to like it as well, ate less and
made smaller gains per pound of milk consumed. Sweet milk gave slightly better results than Bulgaricus milk but not equal to ordinary sour milk. In figuring the money value of sour milk for chickens, we have taken our estimates from the difference in growth between those having sour milk and those having no milk. The figures are taken from eight different experiments conducted over a period of two years, including chickens from three different breeds. _ It was very evident from our observation that milk was worth more the first few days than later on in the life of a chicken, consequently values were worked out by weeks. In converting the milk consumed to a money value, the grain eaten by each lot was figured at 2% cents per pound and the extra gains made by the sour milk pens were credited to the sour milk in terms of money value based on the cost of grain that would have been consumed to produce the same gains without milk. This method of figuring gives the following results : 1st week 4.7 cts. per qt. 2d week 3.6 cts. per qt. 3rd week 2.5 cts. per qt. 4th week 1.4 cts. per qt. 5th week 2.3 cts. per qt. 6th week 1.5 cts. per qt. Average for six weeks 2.5 cents per quart. It will be noted that the lowest value of milk comes in the fourth week with quite a noticeable increase on the fifth week. This we cannot seem to account for except through the fact that milk does not contain the particular protein which _ is necessary for feather growth. Aside from the increased growth which sour milk gives a chicken it has a marked influence on the vigor and vitality of the bird.—ROY JONES.
THE POULTRY DEPARTMENTS. Mr. H. E. Eswine of the Extension Department of the Ohio State University, has charge of the Poultry Educational exhibit which is being staged at the most prominent shows in Ohio. Mr. C. L. Long, formerly in charge of Poultrv Instruction in Extension School of Ohio State Universitv, has resigned to accept the position of Extension Lecturer in Horticulture at the New Hampshire State Agricultural College. The Poultry Departments of Cornell Universitv, Connecticut Agricultural College and New Jersey^ State College of Agriculture are cooperating in the conducting of an extensive educational poultry exhibit and lecture nrogram at the Madison Square Garden Poultry Show which is to be held February twelve to seventeen. The entire Concert hall will be used for educational purposes.