References
- ABPLANALP, H., D. C. LOWRY and J. H. van MIDDELKOOP (in press). Selection for increased incidence of double-yolked eggs in White Leghorn chickens. Br. Poult. Sci. (in press).
- BALL, R. F., R. J. MACKIN, J. F. HILL and A. J. WYATT (1973.) The nature and probable cause of rough egg shells laid by two lines of White Rocks. Poult. Sci. 52: 500.
- BERG, L. R., G. E. BEARSE and C. F. McCLARY, (1949). The development of two lines of S. C. White Leghorns differing in smoothness of egg shells. Poult. Sci. 28: 756.
- CORCELLE, P. (1969). L'héritabilité de la production d'oeufs doubles chez la poule. Ann. Génét. Sél. anim. 1: 195.
- FOSTER, W. H. (1970). Egg shell malformation. Agric. N. Ireland. 45: 213.
- IVY, C. A., M. C. NESHEIM, J. C. GEARY and G. D. RYAN (1972). Frequency of abnormally shaped eggs in White Leghorn hens. Poult. Sci. 51: 1414.
- JAAP, R. G. and J. A. CLANCY (1968). Reproductive idiosyncrasies of the broiler pullet. Proc. 3rd European Poult. Conf., p. 74.
- JAAP, R. G. and F. V. MUIR (1968). Erratic oviposition and egg defects in broiler-type pullets. Poult. Sci. 47: 417.
- KUIT, A. R. and J. H. van MIDDELKOOP (1972). The possibility to avoid irregular ovipositions by means of sex-linked dwarfism. Ann. Génét. Sél. anim. 4: 225.
- LACASSAGNE, L. and J. P. JACQUET (1963). Elevage de poulettes en lumière constante de six heures. Son action sur la croissance, la maturité sexuelle, le poids de l'oeuf et le pourcentage d'oeufs à double jaune en début de ponte. Ann. Zootech. 12: 159.
- LACASSAGNE, L. and J. P. JACQUET (1965). Maturité sexuelle et apparition d'oeufs à double jaune et sans coquille. Role du régime lumineux et du niveau alimentaire. Ann. Zootech. 14: 169.
- LOWRY, D. C. (1967). The incidence of double-yolked eggs in relation to improvement in egg production. Zuchter. 37: 82.
- LOWRY, D. C. and H. ABPLANALP (1967). Selection for an increase in multiple ovulation in chicken. Genetics. 56: 573.
- LOWRY, D. C. and H. ABPLANALP (1968). Genetic parameters in a line of chickens selected for increased multiple ovulation. In: Proc. 12th Int. Congr. Genetics Vol. 1: 272.
- MIDDELKOOP, J. H. van (1971). Shell abnormalities due to the presence of two eggs in the shell gland. Arch. Geflugelk. 35: 122.
- MIDDELKOOP, J. H. van (1972a). Hatching problems of hard-shelled eggs with additional shell deposition produced by broiler mothers. Arch. Geflugelk. 36: 2.
- MIDDELKOOP, J. H. van (1972b). The relationship between ovulation interval of White Plymouth pullets and the laying of abnormal eggs. Arch. Geflugelk. 36: 223.
- MIDDELKOOP, J. H. van (1973). Physiological and genetic aspects of egg production in White Plymouth Rock pullets. Agric. Res. Report 813, Pudoc, Wageningen, The Netherlands.
- MIDDELKOOP, J. H. van and P. B. SIEGEL (1976). Classification of abnormal chicken eggs. Poult. Sci. 55: 1563.
- MIDDELKOOP, J. H. van and P. C. M. SIMONS (1970). Abnormal eggs due to the presence of two eggs in the uterus at the same time. Tijdschr. Diergeneesk. 95: 21.
- MIKAMI, H. and Y. YAMADA (1975). The heritability of liability to lay abnormal eggs. Jap. Poult. Sci. 12: 253.
- PAYNE, C. G. (1975). Day-length during rearing and the subsequent egg production of meat-strain pullets. Br. Poult. Sci. 16: 559.
- REDDY, P. R. K. and P. B. SIEGEL (1976). Selection of bodyweight at eight weeks of age. 11. Ovulation and oviposition patterns. Poult. Sci. 55: 1518.
- ROLAND, D. A. Sr., J. B. THOMPSON, R. A. VOITTLE and R. H. HARMS (1975). Studies on the cause, prevention and artificial creation of pimpled egg shells. Poult. Sci. 54: 1485.
- RZASA, J. and Z. EWY (1970). Effects of vasotocin and oxytocin on oviposition in the hen. J. Reprod. Fert. 21: 549.
- SILBER, J. and P. MÉRAT (1974). Genetical study of the laying of soft-shelled eggs in the fowl. Proc. 15th World's Poult. Congr., p. 491.
- SIMONS, P. C. M. (1971). Structure of the hen egg shell and its physiological consequences. Agric. Res. Rep. 758; Pudoc, Wageningen, The Netherlands.
- TARDATJJAN, G. A. (1968). Effect of physiological early maturity and heredity on the formation of double-yolked eggs in White Leghorn hens. Mater. vses. nauch. Soveshck. Konf. vses. nauchnoissled. tekhnol. Inst. Ptitsev, 3: 55 (cited in: Anim. Br. Abstr. 39: 183, 1971).
- UDALE, R. W. (1972). Defective egg syndrome in growth selected lines of chickens. M.S. thesis-Virginia Polytechnic Institute and State University, Blacksburg, Va, U.S.A.
- UDALE, R. W., P. B. SIEGEL and H. P. van KREY (1972). Rates of ovulation and oviposition in growth selected lines of chickens. Poult. Sci. 51: 2098.
- WARREN, D. C. and H. M. SCOTT (1935). The time factor in egg formation. Poult. Sci. 14: 195.