Abstract
The use of laparoscopic insemination to deposit semen into the tip of the uterine horn ensures fertilization in ewes induced to ovulate at 3-5 weeks post-partum. Acceptable pregnancy rates are achieved if embryos from post-partum donors are transferred to a normal uterine environment yet embryos rarely survive when transferred or returned to a post-partum uterus.
Blastocyst transfer procedures were developed to test whether the post-partum uterus can support conceptus development during the period of rapid growth coincident with the maternal recognition of pregnancy. In Experiment 1, the efficiency of the blastocyst transfer procedure was determined using control ewes >150 days post-partum. Eight of nine recipient ewes established pregnancies and 75% of blastocysts survived to term. In Experiment 2, blastocysts were transferred to control (n = 12) or postpartum (n = 10) recipients that had been induced to ovulate 28 days after lambing during the breeding season. Conceptus development was assessed 96 h after blastocyst transfer on Day 15 of the cycle. At this time, conceptus mass in the seven post-partum ewes which remained pregnant was generally lower than in the 11 corresponding control ewes. Conceptus and endometrial tissues were cultured separately for a further 24 h in vitro in the presence of [H-3]leucine to determine production of oTP-1 and the pregnancy-specific endometrial protein p70 respectively. Oxytocin binding sites were measured in endometrial tissue. Following 96 h culture in a post-partum uterus the conceptus retained its competence to synthesize and secrete ovine trophoblast protein 1 (oTP-1) in vitro. However, despite normal oTP-1 production the conceptus tissue failed to completely suppress endometrial oxytocin receptor binding. The negative correlation between p70 production and oxytocin receptor density implies a possible role for this protein in the suppression of oxytocin receptor synthesis required to prevent luteolysis in pregnant ewes.
| Original language | English |
|---|---|
| Pages (from-to) | 191-200 |
| Number of pages | 10 |
| Journal | Reproduction, Fertility and Development |
| Volume | 5 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - 1993 |
Keywords
- endometrium
- ovine trophoblast protein-1
- recombinant bovine interferon-Alpha-1
- estrous-cycle
- autoradiographical localization
- maternal recognition
- oxytocin receptors
- secretoty proteins
- pregnancy
- sheep
- prostaglandin
Cite this
Conceptus Development In-Vivo, Endomentrial and Conceptus Protein Release In-Vitro Following Blastocyst Transfer to Ewes Induced to Ovulate at 28 Days. / Wallace, Jacqueline; Aitken, Raymond; Cheyne, M. A. .
In: Reproduction, Fertility and Development, Vol. 5, No. 2, 1993, p. 191-200.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Conceptus Development In-Vivo, Endomentrial and Conceptus Protein Release In-Vitro Following Blastocyst Transfer to Ewes Induced to Ovulate at 28 Days
AU - Wallace, Jacqueline
AU - Aitken, Raymond
AU - Cheyne, M. A.
PY - 1993
Y1 - 1993
N2 - The use of laparoscopic insemination to deposit semen into the tip of the uterine horn ensures fertilization in ewes induced to ovulate at 3-5 weeks post-partum. Acceptable pregnancy rates are achieved if embryos from post-partum donors are transferred to a normal uterine environment yet embryos rarely survive when transferred or returned to a post-partum uterus. Blastocyst transfer procedures were developed to test whether the post-partum uterus can support conceptus development during the period of rapid growth coincident with the maternal recognition of pregnancy. In Experiment 1, the efficiency of the blastocyst transfer procedure was determined using control ewes >150 days post-partum. Eight of nine recipient ewes established pregnancies and 75% of blastocysts survived to term. In Experiment 2, blastocysts were transferred to control (n = 12) or postpartum (n = 10) recipients that had been induced to ovulate 28 days after lambing during the breeding season. Conceptus development was assessed 96 h after blastocyst transfer on Day 15 of the cycle. At this time, conceptus mass in the seven post-partum ewes which remained pregnant was generally lower than in the 11 corresponding control ewes. Conceptus and endometrial tissues were cultured separately for a further 24 h in vitro in the presence of [H-3]leucine to determine production of oTP-1 and the pregnancy-specific endometrial protein p70 respectively. Oxytocin binding sites were measured in endometrial tissue. Following 96 h culture in a post-partum uterus the conceptus retained its competence to synthesize and secrete ovine trophoblast protein 1 (oTP-1) in vitro. However, despite normal oTP-1 production the conceptus tissue failed to completely suppress endometrial oxytocin receptor binding. The negative correlation between p70 production and oxytocin receptor density implies a possible role for this protein in the suppression of oxytocin receptor synthesis required to prevent luteolysis in pregnant ewes.
AB - The use of laparoscopic insemination to deposit semen into the tip of the uterine horn ensures fertilization in ewes induced to ovulate at 3-5 weeks post-partum. Acceptable pregnancy rates are achieved if embryos from post-partum donors are transferred to a normal uterine environment yet embryos rarely survive when transferred or returned to a post-partum uterus. Blastocyst transfer procedures were developed to test whether the post-partum uterus can support conceptus development during the period of rapid growth coincident with the maternal recognition of pregnancy. In Experiment 1, the efficiency of the blastocyst transfer procedure was determined using control ewes >150 days post-partum. Eight of nine recipient ewes established pregnancies and 75% of blastocysts survived to term. In Experiment 2, blastocysts were transferred to control (n = 12) or postpartum (n = 10) recipients that had been induced to ovulate 28 days after lambing during the breeding season. Conceptus development was assessed 96 h after blastocyst transfer on Day 15 of the cycle. At this time, conceptus mass in the seven post-partum ewes which remained pregnant was generally lower than in the 11 corresponding control ewes. Conceptus and endometrial tissues were cultured separately for a further 24 h in vitro in the presence of [H-3]leucine to determine production of oTP-1 and the pregnancy-specific endometrial protein p70 respectively. Oxytocin binding sites were measured in endometrial tissue. Following 96 h culture in a post-partum uterus the conceptus retained its competence to synthesize and secrete ovine trophoblast protein 1 (oTP-1) in vitro. However, despite normal oTP-1 production the conceptus tissue failed to completely suppress endometrial oxytocin receptor binding. The negative correlation between p70 production and oxytocin receptor density implies a possible role for this protein in the suppression of oxytocin receptor synthesis required to prevent luteolysis in pregnant ewes.
KW - endometrium
KW - ovine trophoblast protein-1
KW - recombinant bovine interferon-Alpha-1
KW - estrous-cycle
KW - autoradiographical localization
KW - maternal recognition
KW - oxytocin receptors
KW - secretoty proteins
KW - pregnancy
KW - sheep
KW - prostaglandin
U2 - 10.1071/RD9930191
DO - 10.1071/RD9930191
M3 - Article
VL - 5
SP - 191
EP - 200
JO - Reproduction, Fertility and Development
JF - Reproduction, Fertility and Development
SN - 1031-3613
IS - 2
ER -