Berardineli, J. G., Daiiey, R. A., Butcher, R. L. and Inskeep, E. K. 1979. Source of progesterone prior to puberty in beef heifers. J. Anim. Sci. 49: 1276–1280.
Carrick, M. J. and Shelton, J. N. 1969. Oestrogen-progesterone relationships in the induction of oestrus in spayed heifers. J. Endocr. 45: 99–109.
Donaldson, L. E., Bassett, J. M. and Thorburn, G. D. 1970. Peripheral plasma progesterone concentration of cows during puberty, oestrous cycles, pregnancy and lactation, and the effects of undernutrition or exogenous oxytocin on progesterone concentration. J. Endocr. 48: 599–614.
Echternkamp, S. E. and Hansel, W. 1973. Concurrent changes in bovine plasma hormone levels prior to and during the first postpartum estrous cycle. J. Anim. Sci. 37: 1362–1370.
Glencross, R. G. 1982. Influence of progesterone on the post-ovulatory peak in the concentration of plasma oestradiol-17β in cattle. In Factors Influencing Fertility in the Postpartum Cow (ed. Karg, H. and Schallenberger, E.), pp. 234–247. Martinus Nijhoff, The Hague.
Glencross, R. G., Esslemont, R. J., Bryant, M. J. and Pope, G. S. 1981. Relationships between the incidence of pre-ovulatory behaviour and the concentrations of oestradiol-17p and progesterone in bovine plasma. Appl. Anim. Ethol. 7: 141–148.
Glencross, R. G., Munro, I. B., Senior, B. E. and Pope, G. S. 1973. Concentrations of oestradiol-17(5, oestrone and progesterone in jugular venous plasma of cows during the oestrous cycle and in early pregnancy. Ada endocr. Copnh. 73: 374–384.
Glencross, R. G. and Pope, G. S. 1981. Concentration of oestradiol-17β and progesterone in the plasma of dairy heifers before and after cloprostenol-induced and natural luteolysis and during early pregnancy. Anim. Reprod. Sci. 4: 93–106.
Gonzalez-Padilla, E., Wiltbank, J. N. and Niswender, G. D. 1975. Puberty in beef heifers. 1. The interrelationship between pituitary, hypothalamic and ovarian hormones. J. Anim. Sci. 40: 1091–1104.
Karsch, F. J. and Foster, D. L. 1981. Environmental control of seasonal breeding: a common final mechanism governing seasonal breeding and sexual maturation. In Environmental Factors in Mammal Reproduction (ed. Gilmore, D. and Cook, B.), pp. 30–53. Macmillan, London.
Kesler, D. J., Garverick, H. A., Caudle, A. B., Elmore, R. G., Youngouist, R. S. and Bierschwal, C. J. 1980. Reproductive hormone and ovarian changes in cows with ovarian cysts. J. Dairy Sci. 63: 166–170.
Kiser, T. E., Kkaeling, R. R., Rampacek, G. B., Landmeier, B. J., Caudle, A. B. and Chapman, J. D. 1981. Luteinizing hormone secretion before and after ovariectomy in prepubertal and pubertal beef heifers. J. Anim. Sci. 53: 1545–1550.
Morrow, D. A. 1969. Estrous behavior and ovarian activity in pre-pubertal and postpubertal dairy heifers. J. Dairy Sci. 52: 224–227.
Roy, J. H. B., Gillies, Catherine M., Perfitt, M. W. and Stobo, I. J. F. 1980. Effect of season of the year and phase of the moon on puberty and on the occurrence of oestrus and conception in dairy heifers reared on high planes of nutrition. Anim. Prod. 31: 13–26.
Roy, J. H. B., Gillies, C. M. and Shotton, S. M. 1975. Factors affecting first oestrus in cattle and their effects on early breeding. In The Early Calving of Heifers and its Impact on Beef Production (ed. Taylor, J. C.), pp. 128–142. Commission of European Communities, Copenhagen.
Roy, J. H. B. and Stobo, I. J. F. 1978. Research on the composition of milk substitute diets for calves at the National Institute for Research in Dairying: an historical review. Bienn. Rev. Natn. lnst. Res. Dairying, pp. 13–24.
Schillo, K. K., Dierschke, D. J. and Hauser, E. R. 1982. Regulation of luteinizing hormone secretion in prepubertal heifers: increased threshold to negative feedback action of estradiol. J. Anim. Sci. 54: 325–336.
Shotton, Susan M., Roy, J. H. B. and Pope, G. S. 1978. Plasma progesterone concentrations from before puberty to after parturition in British Friesian heifers reared on high planes of nutrition and inseminated at their first oestrus. Anim. Prod. 27: 89–98.
Smith, J. F., Fairclough, R. J., Payne, E. and Peterson, A. J. 1975. Plasma hormone levels in the cow. I. Changes in progesterone and oestrogen during the normal oestrous cycle. N.Z. Jl agric. Res. 18: 123–129.
Staigmiller, R. B., Short, R. E. and Bellows, R. A. 1979. Induction of LH surges with 17β estradiol in prepuberal beef heifers: an age dependent response. Theriogenology 11: 453–459.
Suzuki, O. and Sato, M. 1980. [Puberty and serum levels of progesterone and estradiol-17β in beef heifers.] Bull. Natn. Grassld Res. lnst., Japan 16: 96–103.
Swanson, L. V. and McCarthy, Susan K. 1978. Estradiol treatment and luteinizing hormone (LH) response of prepubertal Holstein heifers. Biol. Reprod. 18: 475–480.