24 MASS. EXPERIMENT STATION BULLETIN 429 



3. The time of onset of wing primary molt had a significant efTect on first- 

 year egg production. 



4. Date of completion of wing primary molt was probably the most important 

 consideration from the standpoint of antecedent egg production. 



5. Birds bred for high fecundity had the ability to lay for a considerable 

 period after wing molt began, and superior layers did not usually stop laying 

 until three or more primaries had been lost. 



6. Males and females bred for high fecundity completed their annual molt 

 later than stock bred for exhibition color. Males usually completed their molt 

 more than a month earlier than females. 



7. A decline in body weight during annual molt was characteristic of exhibi- 

 tion males and females. Males bred for production did not exhibit this decline, 

 but females showed a slight decline at the height of the molt. 



8. Evidence was inconclusive that selective breeding can increase the length 

 of the laying period during wing primary molt. There is evidence, however, that 

 the date of completion of molt is governed by inheritance. 



9. Hatchability during the second laying year may be reduced by extremely 

 long periods of molt as well as by a very late termination of molt. 



REFERENCES 



Bennett, J. C. 1852. The Poultry Book, p. 207. Phillips, Sampson & Co., 



Boston, Mass. 

 Greenwood, A. W. 1936. Physiology of the molt in the fowl. Report Sixth 



World's Poultry Congress 1 :265-269. 

 Hays, F. A. 1943. Egg production versus reproduction in Rhode Island Reds. 



Poultry Sci. 22 (2):118-122. 

 Hays, F. A. 1944. The significance of inherited characters affecting egg pro- 

 duction. Poultry Sci. 23 (4) :3 10-3 13. 

 Hays, F. A., and Ruby Sanborn. 1930. Duration of annual molt in relation to 



egg production. Mass. Agr. Expt. Sta. Bui. 264. 

 Hays, F. A., and Ruby Sanborn. 1939. Breeding for egg production. Mass. 



Agr. Expt. Sta. Bui. 307 (revised). 

 Jull, M. A. 1940. Poultry Breeding, pp. 429-430. John Wiley and Sons, New 



York. 

 Kempster, H. L. 1925. Time of molt as an index to productivity of hens. 



Mo. Agr. Expt. Sta. Bui. 228. 

 Lerner, I. M., and L. W. Taylor. 1941. Factors affecting the duration of the 



annual rest period. Poultry Sci. 20 (6):490-495. 

 Lippincott, W. A., and L. E. Card. 1939. Poultry Production, pp. 143-153 



Lea and Febiger, Philadelphia. 

 Marble, D. R. 1930. The molting factor in judging fowls for egg production 



N. Y. (Cornell) Agr. Expt. Sta. Bui. 503. 

 Rice, J. E., Clara Nixon, and C. A. Rogers. 1908. The molting of fowls. N. Y. 



(Cornell) Agr. Expt. Sta. Bui. 258. 

 Sherwood, R. M. 1922. Correlation between external body characters and 



annual egg production in White Leghorn fowls. Tex. Agr. Expt. Sta. 



Bui. 295. 



Publication of this Document Approved by Commission on Administration and Finance 

 4M 1-46-17629. 



