TY - JOUR
T1 - Short-term effects of exogenous estradiol-17β on blastocyst development during the period of elongation in swine
AU - Cárdenas, H.
AU - Trout, W. E.
AU - Simmen, R. C M
AU - Pope, W. F.
N1 - Funding Information:
Salaries and research support were provided by Hatch Project 814 and State and Federal funds appropriated to The Ohio State University, Columbus, OH 43210. Manuscript No 147-94. Research support was provided in part by USDA grant 91-37203-6385 to RCMS. We wish to thanks Dr R.M. Roberts for his comments.
PY - 1997/5
Y1 - 1997/5
N2 - Objectives were to examine the effects of a single dose (4 mg) of estradiol-17β (E2) on blastocyst development around the period of elongation. Proestrus gilts were induced to ovulate with 750 IU of hCG and were mated before ovulation (normal mating, 24 to 32 h post-hCG) or after ovulation had begun (delayed mating, 43 h post-hCG). This difference in time of mating has been demonstrated to result in approximately a 7-h difference in time of blastocyst elongation. Normally and delay-mated gilts were ovariohysterectomized at 278 h post-hCG or injected with E2 or vehicle (corn oil) at 278 h and then ovariohysterectomized at 290 h post-hCG (five or six gilts per group). Blastocyst size was measured and concentrations of E2, retinol, uteroferrin, insulin-like growth factor-I (IGF-I), uterine plasmin/trypsin inhibitor (UPTI) and protein in uterine flushings were quantified. Blastocyst size and components of uterine flushings did not differ (P > 0.05) between normally and delay-mated gilts at 278 h post-hCG. However, at 290 h post-hCG, normally mated gilts had larger (P < 0.01) blastocysts (small spheres to filamentous) and their flushings tended to contain less (P < 0.07) amounts of retinol than those of delay-mated gilts whose blastocysts ranged from small spheres to ovoidals. Normally mated gilts receiving E2 at 278 h had smaller (P < 0.01) blastocysts and less (P < 0.05) amounts of retinol at 290 h post-hCG than gilts receiving vehicle. Conversely, delay-mated gilts treated with E2 or vehicle did not differ (P > 0.05) in blastocyst size and amounts of components of uterine flushings at 290 h post-hCG. Normally mated gilts treated with vehicle had litters in the process of elongating at 290 h post-hCG. Mean blastocyst size (P < 0.001) and amounts of components of uterine flushings (except for IGF-I) in these gilts were greater (P < 0.05, UPTI = 0.06) than in normally mated gilts at 278 h post-hCG, whose blastocysts were spherical. Among gilts not treated with E2 (278 h and 290 h pooled), mean blastocyst size was positively correlated (P < 0.05) with amounts of retinol, E2, uteroferrin and total protein. Results indicated that a single dose of E2 given before elongation altered blastocyst development depending on how close blastocysts were to onset of elongation at the time of E2 treatment.
AB - Objectives were to examine the effects of a single dose (4 mg) of estradiol-17β (E2) on blastocyst development around the period of elongation. Proestrus gilts were induced to ovulate with 750 IU of hCG and were mated before ovulation (normal mating, 24 to 32 h post-hCG) or after ovulation had begun (delayed mating, 43 h post-hCG). This difference in time of mating has been demonstrated to result in approximately a 7-h difference in time of blastocyst elongation. Normally and delay-mated gilts were ovariohysterectomized at 278 h post-hCG or injected with E2 or vehicle (corn oil) at 278 h and then ovariohysterectomized at 290 h post-hCG (five or six gilts per group). Blastocyst size was measured and concentrations of E2, retinol, uteroferrin, insulin-like growth factor-I (IGF-I), uterine plasmin/trypsin inhibitor (UPTI) and protein in uterine flushings were quantified. Blastocyst size and components of uterine flushings did not differ (P > 0.05) between normally and delay-mated gilts at 278 h post-hCG. However, at 290 h post-hCG, normally mated gilts had larger (P < 0.01) blastocysts (small spheres to filamentous) and their flushings tended to contain less (P < 0.07) amounts of retinol than those of delay-mated gilts whose blastocysts ranged from small spheres to ovoidals. Normally mated gilts receiving E2 at 278 h had smaller (P < 0.01) blastocysts and less (P < 0.05) amounts of retinol at 290 h post-hCG than gilts receiving vehicle. Conversely, delay-mated gilts treated with E2 or vehicle did not differ (P > 0.05) in blastocyst size and amounts of components of uterine flushings at 290 h post-hCG. Normally mated gilts treated with vehicle had litters in the process of elongating at 290 h post-hCG. Mean blastocyst size (P < 0.001) and amounts of components of uterine flushings (except for IGF-I) in these gilts were greater (P < 0.05, UPTI = 0.06) than in normally mated gilts at 278 h post-hCG, whose blastocysts were spherical. Among gilts not treated with E2 (278 h and 290 h pooled), mean blastocyst size was positively correlated (P < 0.05) with amounts of retinol, E2, uteroferrin and total protein. Results indicated that a single dose of E2 given before elongation altered blastocyst development depending on how close blastocysts were to onset of elongation at the time of E2 treatment.
KW - Blastocyst
KW - Embryology
KW - Oestradiol-pig
KW - Pig
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U2 - 10.1016/S0378-4320(97)00005-5
DO - 10.1016/S0378-4320(97)00005-5
M3 - Article
C2 - 9233512
AN - SCOPUS:0343554646
SN - 0378-4320
VL - 47
SP - 123
EP - 135
JO - Animal Reproduction Science
JF - Animal Reproduction Science
IS - 1-2
ER -