Hostname: page-component-78c5997874-lj6df Total loading time: 0 Render date: 2024-11-10T06:54:22.389Z Has data issue: false hasContentIssue false

XXV.—An Experimental Analysis of the Plumage of the Brown Leghorn Fowl

Published online by Cambridge University Press:  15 September 2014

A. W. Greenwood
Affiliation:
Animal Breeding Research Department, University of Edinburgh
J. S. S. Blyth
Affiliation:
Animal Breeding Research Department, University of Edinburgh
Get access

General summary

1. The plumage of the Brown Leghorn fowl is analysed and the extent of its dependence on the activity of the thyroid and gonad is discussed.

2. Hypothyroidism results (a) in a diminution in the amount of melanin and a coincident increase in the red pigment; (b) in an increase in the amount of fringing due to a lack of barbule formation. The female pattern tends to disappear.

3. Hyperthyroidism in the male gives exactly the opposite effect—i.e. the melanin increases in amount while the red pigment and fringing tend to disappear. In the female the effect of hyperthyroidism is slight, and with moderate doses of thyroid there is practically no modification of the female pattern of pencilling and no melanin appears in the breast. The neck hackle, however, becomes darker and shows a decrease in fringing.

4. From these results, together with what is known concerning the effect of gonad on plumage, a hypothesis is advanced, that whereas the plumage typical of the male is developed independently of the gonad and depends for its maintenance on a certain level of thyroid functioning, both gonad and thyroid play a part in regard to that of the female; the former stimulates the latter to a higher level of activity than that present in the male and so indirectly causes a hyperthyroid effect on the feathers. At the same time it modifies this condition by acting directly on the feathers and restricting the deposition of melanin.

5. The fact that in both sexes the plumage in the young chick is similar to that of the female puts this theory in question. There is evidence to show, however, that yolk may have a modifying effect on plumage similar to that of the ovary, and thus the doubt regarding the validity of the hypothesis can be removed by the suggestion that the chick plumage develops under the influence of the yolk in its own yolk sac. This second theory gains confirmation by a study of the atypical plumage which is occasionally met with in growing females, and also by a consideration of the type of plumage developed in juvenile females following the successful implantation of testis.

Type
Proceedings
Copyright
Copyright © Royal Society of Edinburgh 1930

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Cole, L. J., and Reid, D. H. (1924). “The Effect of Feeding Thyroid on the Plumage of the Fowl,” Jour. Agric. Res., vol. xxix, No. 6, pp. 285287.Google Scholar
2.Cooper, E. R. A. (1925). “The Histology of the more Important Human Endocrine Organs at Various Ages,” Oxford Medical Publication.Google Scholar
3.Crew, F. A. E. (1927). “Die Wirkungen der Schildrüsenektomie am hennengefiederten Haln,” Arch. f. Geflug., vol. i, No. 7, pp. 234239.Google Scholar
4.Domm, L. V. (1927). “New Experiments on Ovariotomy and the Problem of Sex Inversion in the Fowl,” Jour. Exp. Zool., vol. xlviii, No. 1, pp. 31171.CrossRefGoogle Scholar
5.Greenwood, A. W. (1928). “Studies on the Relation of Gonadic Structure to Plumage Characterisation in the Domestic Fowl.—IV. Gonad Cross-Transplantation in Leghorn and Campine,” Proc. Roy. Soc., B, vol. ciii, pp. 7381.Google Scholar
6.Horning, B., and Torrey, H. B. (1927). “Thyroid and Gonad as Factors in the Production of Plumage Melanins in the Domestic Fowl,” Biol. Bull., vol. liii, No. 4, pp. 221232.CrossRefGoogle Scholar
7.Kopec, S., and Greenwood, A. W. (1929). “The Effect of Yolk Injections on Plumage in the Ovariotomised Fowl,” Roux' Arch. f. Entw. mech. (in the press).Google Scholar
8.Křiženeckÿ, J., and Nevalonnyj, M. (1927). “Weitere Versuche über den Einfluss der Schilddrüse und der Thymus auf die Entwicklung des Gefieders bei den Hühnenkücken,” Roux' Arch. f. Entw. mech., vol. cxii, pp. 594639.CrossRefGoogle Scholar
9.Kuhn, O. (1927). “Die Differenzierung des Haushuhngefieders durch Schilddrüse und Gonaden,” Zuchtungskunde, vol. iii, No. 2, p. 62.Google Scholar
10.Latimer, H. B. (1924). “Post-natal Growth of the Body Systems and Organs of the Single Comb White Leghorn Chicken,” Jour. Agric, Res., vol. xxix, pp. 363397.Google Scholar
11.Pezard, Sand, , and Caridroit, (1925). “L'évolution des Potentialités chez la Poulette,” C.R. Soc. de Biol., vol. xcii, pp. 495496.Google Scholar
12.Ridgway, R. (1886). A Nomenclature of Colors for Naturalists, Little Brown & Company, Boston.Google Scholar
13.Roxas, H. A. (1926). “Gonad Cross-Transplantation in Sebright and Leghorn Fowls,” Jour. Exp. Zool., vol. xlvi, No. 1, pp. 63113.CrossRefGoogle Scholar
14.Schafer, E. Sharpey (1924). The Endocrine Organs, 2nd edit., Longmans Green & Company, London.Google Scholar
15.Uhlenhuth, and Karns, (1927). Anat. Rec, vol. xxxv, No. 1 Abs., p. 27.Google Scholar
16.Wilson, G. E. (1927). “The Thyroid Follicle in Man, its Normal and Pathological Configuration,” Anat. Rec, vol. xxxvii, pp. 3161.CrossRefGoogle Scholar
17.Zawadovsky, B.M. (1927). “Zur Frage der Wechselbeziehungen zwischen Schilddrüse und Geschlechtsdrüsen bei Hühnern,” Roux' Arch. f. Entw. mech., vol. cx, No. 1, pp. 149182.CrossRefGoogle Scholar
18.Zawadovsky, B.M., and Rochlin, M. (1928). “Zur Frage nach dem Einfluss der Hyperthyreoidisierung auf die Färbung und Geschlechtsstruktur des Hühnergefieders,” Roux' Arch. f. Entw. mech., vol. cxiii, No. 2, pp. 323345.Google Scholar