Corpus luteum function in the pig: progesterone profiles of cyclic and pregnant gilts.

Progesterone profiles of 7 cycling gilts and those of 6 gilts inseminated on day 1 (1 day after the onset of oestrus) were studied. The results showed that plasma progesterone concentration in the inseminated group was higher (P<0.05) from day 14 onwards, indicating that the "rescue" of the corpus luteum (i.e. from luteolyis) for pregnancy occurs before day 14. In 1 of the inseminated gilts, the progesterone concentration declined on day 27, and the gilt returned to oestrus on day 30. The progesterone and oestrone sulphate profiles of this gilt indicated that the return to oestrus may have been caused by embryonic loss before day 14 after a 1st signal for corpus luteum maintenance has been generated. Another gilt aborted on day 27. The data on this gilt indicate that pregnancy failure may have been caused by a maternal malfunction.

[1]  R. Rajamahendran,et al.  Comparison of plasma progesterone profiles in cyclic, pregnant, pseudopregnant and hysterectomized pigs between 8 and 27 days after oestrus. , 1988, The Journal of endocrinology.

[2]  F. Helmond,et al.  Effect of flushing of blastocysts on days 10-13 on the life-span of the corpora lutea in the pig. , 1988, Journal of reproduction and fertility.

[3]  J. A. Foulkes,et al.  Occurrence of two phases of return to oestrus in sows on commercial units , 1988, Veterinary Record.

[4]  R. Wettemann,et al.  Length of pseudopregnancy and pattern of uterine protein release as influenced by time and duration of oestrogen administration in the pig. , 1987, Journal of reproduction and fertility.

[5]  P. Dziuk,et al.  Relationship between the level of estrone sulfate in the plasma and the number of fetuses during pregnancy in the gilt. , 1983, Biology of reproduction.

[6]  N. First,et al.  Effect of removal of follicles, corpora lutea or ovaries on maintenance of pregnancy in swine. , 1981, Journal of animal science.

[7]  P. R. Hein,et al.  The effects of progesterone on estrogen-induced luteinizing hormone and follicle-stimulating hormone release in the female rhesus monkey. , 1980, Endocrinology.

[8]  N. Saba,et al.  Estimation of oestrone sulphate in the serum of pregnant sows. , 1980, Journal of reproduction and fertility.

[9]  H. W. Norton,et al.  The effect of corpora lutea induced during pregnancy on the length of gestation in the pig. , 1977, Biology of reproduction.

[10]  C. J. Wilcox,et al.  A study of prostaglandin F2alpha as the luteolysin in swine: II Characterization and comparison of prostaglandin F, estrogens and progestin concentrations in utero-ovarian vein plasma of nonpregnant and pregnant gilts. , 1977, Prostaglandins.

[11]  F. Ellendorff,et al.  Prospects and problems of pregnancy and fertility diagnosis in the pig by aid of progesterone determination. , 1976, The British veterinary journal.

[12]  H. Hawk.  Effect of prostaglandin F2α on luteal function in swine , 1975 .

[13]  G. J. King,et al.  Plasma concentrations of progesterone, oestrone, oestradiol-17beta and of oestrone sulphate in the pig at implantation, during pregnancy and at parturition. , 1974, Journal of reproduction and fertility.

[14]  N. First,et al.  Effects of ovariectomy, dexamethasone and progesterone on the maintenance of pregnancy in swine. , 1973, Journal of animal science.

[15]  P. Dziuk,et al.  Minimum daily dose of progesterone and plasma concentration for maintenance of pregnancy in ovariectomized gilts. , 1973, Biology of reproduction.

[16]  H. D. Guthrie,et al.  Plasma estrogen, progesterone, and luteinizing hormone prior to estrus and during pregnancy in pigs. , 1972, Endocrinology.

[17]  H. D. Guthrie,et al.  Plasma estrogen, progesterone and luteinizing hormone levels during the estrous cycle in pigs. , 1972, Biology of reproduction.

[18]  G. Niswender,et al.  Radioimmunoassay of serum levels of luteinizing hormone throughout the estrous cycle in pigs. , 1970, Endocrinology.

[19]  L. Ewing,et al.  Peripheral plasma progesterone levels in pigs during the oestrous cycle. , 1969, Journal of reproduction and fertility.

[20]  P. Dziuk,et al.  Effect on pregnancy in the pig after killing embryos or fetuses in one uterine horn in early gestation. , 1968, Journal of animal science.