scholarly journals Paradoxical effect of supplementary progesterone between Day 3 and Day 7 on corpus luteum function and conceptus development in cattle

2014 ◽  
Vol 26 (2) ◽  
pp. 328 ◽  
Author(s):  
L. O'Hara ◽  
N. Forde ◽  
F. Carter ◽  
D. Rizos ◽  
V. Maillo ◽  
...  
Keyword(s):  
Corpus Luteum ◽  
Prostaglandin F2α ◽  
Strongly Correlated ◽  
Negative Effects ◽  
Fluid Medium ◽  
Treatment Groups ◽  
Paradoxical Effects ◽  
Conceptus Development ◽  
Positive Effect

The aim of the present study was to investigate the effect of short-term progesterone (P4) supplementation during the early metoestrous period on circulating P4 concentrations and conceptus development in cattle. The oestrous cycles of cross-bred beef heifers were synchronised using a 7-day P4-releasing intravaginal device (PRID® Delta; 1.55 g P4) treatment with administration of a prostaglandin F2α analogue (Enzaprost; CEVA Sante Animale) the day before PRID® Delta removal. Only those heifers recorded in standing oestrus (Day 0) were used. In Experiment 1, heifers were randomly assigned to one of five groups: (1) control: no treatment; (2) placebo: insertion of a blank device (no P4) from Day 3 to Day 7; (3) insertion of a PRID® Delta from Day 3 to Day 7; (4) insertion of a PRID® Delta from Day 3 to Day 5; or (5) insertion of a PRID® Delta from Day 5 to Day 7. In vitro-produced blastocysts were transferred to each heifer in Groups 2–5 on Day 7 (n = 10 blastocysts per heifer) and conceptuses were recovered when heifers were killed on Day 14. Based on the outcome of Experiment 1, in Experiment 2 heifers were artificially inseminated at oestrus and randomly assigned to one of three treatment groups: (1) placebo; (2) PRID from Day 3 to Day 5; or (3) PRID from Day 3 to Day 7. All heifers were killed on Day 16 and recovered conceptuses were incubated in synthetic oviducal fluid medium for 24 h; spent media and uterine flushes were analysed for interferon-τ (IFNT). In both experiments, daily blood samples were taken to determined serum P4 concentrations. Data were analysed using the PROC MIXED procedure of SAS (SAS Institute, Cary, NC, USA). Insertion of a PRID resulted in an increase (P < 0.05) in serum P4 that declined following removal. In Experiment 1, P4 supplementation from Day 3 to Day 5 (17.0 ± 1.4 mm) or Day 3 to Day 7 (11.3 ± 2.3 mm) increased conceptus length compared with placebo (2.1 ± 1.8 mm). Serum P4 was significantly lower from Day 9 to Day 14 (P < 0.05) and the weight of the Day 14 corpus luteum (CL) was lower in the PRID Day 3–7 group than the placebo or control groups. In Experiment 2, supplementation from Day 3 to Day 5 (94.0 ± 18.8 mm) or Day 3 to Day 7 (143.6 ± 20.6 mm) increased conceptus length on Day 16 compared with placebo (50.3 ± 17.4 mm). Serum P4 was significantly lower in the two supplemented groups following PRID removal compared with placebo (P < 0.05) and was associated with a lower CL weight in the Day 3–7 group. Conceptus length was strongly correlated with the IFNT concentration in the uterine flush (r = 0.58; P = 0.011) and spent culture medium (r = 0.68; P < 0.002). The findings of the present study highlight the somewhat paradoxical effects of P4 supplementation when given in the early metoestrous period in terms of its positive effect on conceptus development and its potentially negative effects on CL lifespan.

109 EFFECT OF SHORT TERM PROGESTERONE SUPPLEMENTATION ON CIRCULATING PROGESTERONE CONCENTRATION, CORPUS LUTEUM SIZE, AND EARLY EMBRYO DEVELOPMENT IN CATTLE

2013 ◽  
Vol 25 (1) ◽  
pp. 202
Author(s):  
L. O'Hara ◽  
N. Forde ◽  
D. Rizos ◽  
V. Maillo ◽  
A. D. Ealy ◽  
...  
Keyword(s):  
Corpus Luteum ◽  
Early Embryo ◽  
Negative Effects ◽  
Short Term ◽  
Concentration Data ◽  
Interferon Tau ◽  
Fluid Medium ◽  
Conceptus Development ◽  
Oviduct Fluid

The aim of this study was to investigate the effect of short term progesterone (P4) supplementation on circulating P4 concentrations, corpus luteum (CL) size, and conceptus development in cattle. The oestrous cycles of crossbred beef heifers were synchronised using a 7-day PRID® Delta (1.55 g P4) treatment with administration of a PGF2α analog (Enzaprost®) the day before PRID® Delta removal. Only those recorded in standing oestrus (Day 0) were used. In Experiment 1, heifers were randomly assigned to 1 of 5 groups: (1) control: no treatment, (2) placebo: insertion of a blank device (no P4) from Day 3 to 7, (3) insertion of a PRID® Delta from Day 3 to 7, (4) insertion of a PRID® Delta from Day 3 to 5, or (v5) insertion of a PRID® Delta from Day 5 to 7. In vitro produced blastocysts were transferred to each heifer on Day 7 (10 blastocysts per heifer) and conceptuses were recovered at slaughter on Day 14. In Experiment 2 heifers were artificially inseminated at oestrus and randomly assigned to 1 of 3 treatment groups (1) placebo, (2) PRID® Delta from Day 3 to 5, or (3) PRID® Delta from Day 3 to 7. All heifers were slaughtered on Day 16, and recovered conceptuses were incubated in synthetic oviduct fluid medium for 24 h; spent media and uterine flushes were analysed for interferon-tau (IFNT). In both experiments, daily blood samples were taken to measure serum P4 concentration. Data were analysed using the PROC MIXED procedure of SAS (SAS Institute Inc., Cary, NC, USA). Insertion of a PRID® Delta resulted in an increase (P < 0.05) in serum P4, which declined following removal. In Experiment 1, serum P4 concentration was significantly lower from Day 9 to 14 (P < 0.05) and Day 14 CL weight was lower in the PRID® Delta Day 3 to 7 group than the placebo or control groups. P4 supplementation from Day 3 to 5 (17.0 ± 1.4 mm) or Day 3 to 7 (11.3 ± 2.3 mm) increased conceptus length compared to the placebo (2.1 ± 1.8 mm). In Experiment 2, serum P4 was significantly lower in the two supplemented groups following PRID® Delta removal compared with the placebo (P < 0.05) and was associated with a lower CL weight in the Day 3 to 7 group. Supplementation from Day 3 to 5 (94.0 ± 18.8 mm) or Day 3 to 7 (143.6 ± 20.6 mm) increased conceptus length on Day 16 compared to the placebo (50.3 ± 17.4 mm). Conceptus length was strongly correlated with the concentration of IFNT in the uterine flush (r = 0.58; P = 0.011) and spent culture medium (r = 0.68; P < 0.002). These findings highlight the somewhat paradoxical effects of P4 supplementation when given in the early metoestrus period in terms of its positive effect on conceptus development and its potentially negative effects on CL lifespan. Supported by CEVA Sante Animale and Science Foundation Ireland (07/SRC/B1156).

102 UNILATERAL AND BILATERAL TRANSFER OF 2IN VITRO-PRODUCED EMBRYOS INCREASES PREGNANCY LOSS BETWEEN 30 AND 60 DAYS

2017 ◽  
Vol 29 (1) ◽  
pp. 159
Author(s):  
L. C. Carrenho-Sala ◽  
A. Garcia-Guerra ◽  
R. V. Sala ◽  
M. Fosado ◽  
D. C. Pereira ◽  
...  
Keyword(s):  
Corpus Luteum ◽  
Pregnancy Loss ◽  
Prostaglandin F2α ◽  
Poor Quality ◽  
Single Group ◽  
Treatment Groups ◽  
Bilateral Group ◽  
Conception Rates ◽  
Twin Pregnancies

Fertility of in vitro-produced embryos is affected by embryo stage and quality. Embryos quality 1 and stage 7 result in higher fertility than embryos of earlier stages and/or lower quality. The objective was to evaluate the effect of unilateral and bilateral transfer of 2 in vitro-produced embryos of earlier stages and/or poor quality on fertility. Heifers were synchronized using a 5-day CIDR Synch or 2 prostaglandin F2α injections 14 days apart followed by oestrus detection. Embryo transfer was performed 7 ± 1 day after gonadotropin-releasing hormone/oestrus and heifers were assigned randomly to 1 of 3 groups: single embryo ipsilateral to the corpus luteum (single; n = 188); 2 embryos in the uterine horn ipsilateral to the corpus luteum (unilateral; n = 138); 2 embryos bilaterally (bilateral; n = 128). Embryos stage 4 to 8 and quality 1 or 2 were randomly assigned to treatment groups. All embryos were 7-day fresh in vitro-produced embryos, and pregnancy diagnosis was performed by ultrasonography on Days 32 and 60. Data were analysed by logistic regression. Conception rates on Days 32 and 60 were not different (P > 0.10) between heifers receiving a single embryo [Day 32 = 30.9% (58/188) and Day 60 = 25% (47/188)] or those receiving 2 embryos [Day 32 = 36.5% (97/266) and Day 60 = 22.2% (59/266)]. However, pregnancy loss between Days 32 and 60 was greater (P < 0.01) in heifers with 2 embryos (39.2%; 38/97) than in those with a single embryo (18.9%; 11/58). Conception rate on Day 32 was not different between groups (P = 0.4) and was 30.9% (58/188) for single, 36.9% (51/138) for unilateral, and 35.9% (46/128) for bilateral. Similarly, there was no difference (P = 0.8) in conception rates on Day 60, single = 25% (47/188), unilateral = 23.9% (33/138), and bilateral= 20.3% (26/128). However, there was an effect of group on pregnancy loss between Days 32 and 60 (P = 0.04). Losses were higher (P = 0.01) in the bilateral group [43.5% (20/46)] compared with the single group [18.9% (11/58)], and the unilateral group was intermediate [35.3% (18/51)] and tended to be different from the single group (P = 0.1). Interestingly, when pregnancy loss was compared between heifers with twin or single pregnancies, as determined by ultrasonography, and regardless of the number of embryos transferred or their location, twin pregnancies had a greater pregnancy loss [62.1% (18/29)] compared with single pregnancies [24.6% (31/126); P < 0.01]. For twin bearing heifers, as determined by ultrasonography on Day 32, pregnancy loss did not differ between unilateral (62.5%; 10/16) and bilateral (61.5%; 8/13) transfers (P = 0.9). Similarly, there was no difference (P = 0.2) for heifers with single embryo pregnancies: single (18.9%; 11/58), unilateral (22.9%; 8/35), bilateral (36.4%; 12/33), although bilateral transfer of 2 embryos tended to be higher than single (P = 0.07). Transfer of 2 low quality in vitro-produced embryos results in similar conception rates, although pregnancy losses are greater. Interestingly, only 30% (29/97) of the pregnancies from heifers that received 2 embryos contained twins, indicating the loss of one of the embryos before Day 32. Furthermore, the increased losses observed with the transfer of 2 embryos were attributed to those heifers in which twin pregnancies were diagnosed on Day 32 regardless of distribution.

scholarly journals Prostaglandin F2α Represses IGF-I-Stimulated IRS1/Phosphatidylinositol-3-Kinase/AKT Signaling in the Corpus Luteum: Role of ERK and P70 Ribosomal S6 Kinase

2010 ◽  
Vol 24 (3) ◽  
pp. 632-643 ◽  
Author(s):  
Edward Arvisais ◽  
Xiaoying Hou ◽  
Todd A. Wyatt ◽  
Koumei Shirasuna ◽  
Heinrich Bollwein ◽  
...  
Keyword(s):  
Corpus Luteum ◽  
Prostaglandin F2α ◽  
Serine Phosphorylation ◽  
Phosphatidylinositol 3 Kinase ◽  
Akt Activation ◽  
Diminished Capacity ◽  
Igf I ◽  
In Vitro Treatment

Abstract Little is known about the early intracellular events that contribute to corpus luteum regression. Experiments were designed to determine the effects of prostaglandin F2α (PGF2α) on phosphatidylinositol-3-kinase (PI3K)/Akt signaling in the corpus luteum in vivo and in vitro. Treatment of midluteal-phase cows with a luteolytic dose of PGF2α resulted in a rapid increase in ERK and mammalian target of rapamycin (mTOR)/p70 ribosomal protein S6 kinase (p70S6K1) signaling and a rapid suppression of Akt phosphorylation in luteal tissue. In vitro treatment of primary cultures of luteal cells with PGF2α also resulted in an increase in ERK and mTOR/p70S6K1 signaling and a diminished capacity of IGF-I to stimulate PI3K, Akt, and protein kinase C ζ activation. Accounting for the reductions in PI3K and Akt activation observed in response to PGF2α treatment, we found that PGF2α promoted the phosphorylation of serine residues (307, 612, 636) in the insulin receptor substrate 1 (IRS1) peptide sequence in vivo and in vitro. Serine phosphorylation of IRS1 was associated with reduced formation of IGF-I-stimulated IRS1/PI3Kp85 complexes. Furthermore, treatment with inhibitors of the MAPK kinase 1/ERK or mTOR/p70S6K1 signaling pathways prevented PGF2α-induced serine phosphorylation of IRS1 and abrogated the inhibitory actions of PGF2α on Akt activation. Taken together, these experiments provide compelling evidence that PGF2α treatment stimulates IRS1 serine phosphorylation, which may contribute to a diminished capacity to respond to IGF-I. It seems likely that the rapid changes in phosphorylation events are among the early events that mediate PGF2α-induced corpus luteum regression.

108 FACTORS AFFECTING PREGNANCY RATES IN RECIPIENTS RECEIVING IN VITRO-PRODUCED EMBRYOS BY FIXED TIME EMBRYO TRANSFER

2016 ◽  
Vol 28 (2) ◽  
pp. 184
Author(s):  
M. Pelizzari ◽  
A. Tribulo ◽  
J. Garzon ◽  
B. Bernal ◽  
R. Tribulo ◽  
...  
Keyword(s):  
Corpus Luteum ◽  
Embryo Transfer ◽  
Body Condition Score ◽  
Prostaglandin F2α ◽  
Fixed Time ◽  
Pregnancy Rates ◽  
Uterine Horn ◽  
Device Removal ◽  
Embryo Transfer Technique

A retrospective analysis of factors that affect pregnancy rates from 4214 fresh in vitro-produced (IVP) embryos that were transferred at a fixed-time (FTET) in 20 different farms. Recipients were all cycling cows or heifers that were synchronized with 1 of 3 treatments: 1) treatments with progesterone (P4) devices and 2 mg of oestradiol benzoate (EB) on Day 0 (day of insertion) and 24 h after device removal (Day 8); 2) treatments with P4 devices and EB on Day 0, but with 0.5 mg of oestradiol cypionate (ECP) at device removal (Day 8); or 3) treatments with P4 devices and GnRH on Day 0 and a second GnRH 60 h after device removal (Day 5). Cows in all treatment groups also received 500 µg of cloprostenol (prostaglandin F2α) at the time of P4 device removal and 400 IU of eCG either at device removal or 3 days before device removal. All embryos were transferred 7 or 8 days after the expected time of oestrus (24 h after EB, 48 h after ECP or at the time of the second GNRH for each synchronization treatment, respectively). On the day of embryo transfer, recipients were examined by ultrasonography and those with corpus luteum >14 mm in diameter received a fresh, IVP embryo in the uterine horn ipsilateral to the corpus luteum. Pregnancy rates were determined by ultrasonography 35 days after FTET. Data were analysed by logistic regression. Independent variables were classified into the following three categories. 1) Factors related to the recipient and the environment; there were no significant differences in pregnancy rates for corpus luteum diameter (≥14 and <16 mm, ≥16 and <18 mm, or ≥18 mm; P = 0.46), number of corpus luteum (1 or ≥2; P = 0.26), and category of recipient (cow or heifer; P = 0.21). However, there were significant effects of farm (P = 0.01) and body condition score (BCS; P = 0.01). Cows with BCS ≥4.5 (1 to 5 scale) resulted in lower pregnancy rates (4/20, 20.0%) than those with BCS 2 (74/225, 32.9%), 2.5 (502/1434, 35.0%), 3 (570/1467, 38.9%), 3.5 (193/532, 36.3%), and 4 (44/118, 37.3%). 2) Factors related to the synchronization treatment; there were no significant differences between recipients receiving eCG at device removal (84/209, 40.2%) or 3 days before device removal (874/2291, 38.1%; P = 0.35). However, recipients synchronized with P4 devices and ECP had higher (P = 0.01) pregnancy rates (232/483, 48.0%) than those treated with EB (679/1888, 36.0%) or gonadotropin-releasing hormone (47/129, 36.4%). 3) Factors related to the embryo transfer technique; day of the recipient’s oestrous cycle (P = 0.36), stage of embryo transferred (IETS stages 6 or 7; P = 0.62), and operator (P = 0.57) did not affect pregnancy rates. However transfers made in the anterior third of the uterine horn resulted in higher (649/1545, 42.0%) pregnancy rates than those in the mid-third (845/2511, 33.6%) or in the distal third (6/35, 17.1%; P = 0.01). It was concluded that factors related to the recipient and the environment (farm and BCS), the synchronization treatment (ECP), and the embryo transfer technique (site of deposition) affect pregnancy rates in recipients of embryos produced in vitro and transferred at a fixed time.

100 EMBRYO SURVIVAL AND CONCEPTUS ELONGATION FOLLOWING ASYNCHRONOUS EMBRYO TRANSFER IN CATTLE

2015 ◽  
Vol 27 (1) ◽  
pp. 143
Author(s):  
F. Randi ◽  
B. Fernandez ◽  
M. McDonald ◽  
C. Johnson ◽  
N. Forde ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Prostaglandin F2α ◽  
Early Embryo ◽  
Embryo Survival ◽  
Treatment Groups ◽  
Length Data ◽  
Uterine Environment ◽  
To Receive ◽  
Intravaginal Device

Maternal progesterone (P4) regulates early conceptus growth and development in ruminants. Early embryo transfer studies in sheep and cattle demonstrated a need for close synchrony between the embryo and the uterine environment of the recipient. However, manipulating P4 may be one way of strategically regulating the temporal changes that normally occur in the uterine environment in order to allow flexibility in the timing of embryo transfer. For example, previous studies have demonstrated that P4 administration during the first few days of the oestrous cycle facilitates pregnancy establishment with older embryos. The aim of this study was to examine the effect of embryo-uterine synchrony on conceptus elongation in cattle. Oestrous cycles of crossbred beef heifers were synchronised using an 8-day P4-Releasing Intravaginal Device (PRID Delta®, CEVA, Mountain View, CA, USA) with administration of a prostaglandin F2α analogue (Enzaprost®, CEVA; 5 mL equivalent to 25 mg of dinoprost) given on the day before PRID removal. Heifers were checked for signs of oestrus 4 times per day commencing 30 h after PRID withdrawal. Only those seen in standing oestrus (n = 50) were randomly assigned to 1 of 5 treatment groups to receive Day 7 in vitro-produced blastocysts (n = 10 per recipient) (1) on Day 5 post-oestrus; (2) on Day 5, with P4 supplementation via PRID from Day 3 to 5 + 750 IU of eCG at PRID insertion; (3) on Day 5, PRID Delta from Day 3 to 5 plus 3000 IU of hCG at PRID insertion; (4) on Day 7, or (5) on Day 9. At embryo age Day 14, all heifers were slaughtered and the uterus was flushed to recover and measure conceptuses. Data are summarised in Table 1. Fewer recipients yielded conceptuses (P < 0.05) and fewer conceptuses overall were recovered (P < 0.05) following transfer on Day 5 compared with Day 7 or Day 9. Supplementation with P4 resulted in short cycles (evidenced by corpus luteum regression and/or a recent ovulation at slaughter) in 33.3 to 54.5% of recipients receiving embryos on Day 5. Mean conceptus length was greater (P < 0.05) following transfer to an advanced uterus. In conclusion, transfer of embryos to a retarded (Day 5) uterine environment results in poor embryo survival. Supplementation with P4 shortened the interoestrous period in a significant number of heifers. Transfer to an advanced uterine environment promotes conceptus elongation, presumably driven by P4. Table 1.Embryo survival and conceptus length data

80 RECIPIENT SERUM PROGESTERONE CONCENTRATION AND EARLY CONCEPTUS DEVELOPMENT IN BOVINE EMBRYOS PRODUCED IN VIVO OR IN VITRO

2012 ◽  
Vol 24 (1) ◽  
pp. 152
Author(s):  
C. V. Barnwell ◽  
C. S. Whisnant ◽  
C. E. Farin ◽  
J. E. Alexander ◽  
P. W. Farin
Keyword(s):  
State University ◽  
Progesterone Concentration ◽  
Serum Progesterone ◽  
Exact Test ◽  
Treatment Groups ◽  
Conceptus Development ◽  
Development Outcomes ◽  
The Relationship

The majority of pregnancy loss in cattle occurs during the first 2 to 3 weeks of pregnancy. This loss can be studied by the transfer of in vivo- and in vitro-produced embryos. The objective of this study was to examine the relationship between recipient serum progesterone levels both at the time of embryo transfer and at conceptus recovery on conceptus development from in vivo- or in vitro-produced embryos. Embryos were produced in vivo by superovulation of Holstein cows (IVO; n = 17) or in vitro with either serum-containing (IVPS; n = 27) or serum-restricted medium (IVPSR; n = 34). Single grade-1 blastocysts from each embryo production system were transferred into heifers at Day 7. Conceptuses were recovered at Day 17 of gestation (number recovered/number transferred: IVO, 11/17; IVPS, 16/27; IVPSR, 18/34) and classified as complete, degenerated, or no conceptus. Recipient serum progesterone concentrations were determined by radioimmunoassay and compared with conceptus development outcomes. Sex of conceptus was determined by PCR using a Y-chromosome specific probe. Data were analysed using Fisher's exact test or ANOVA and Duncan's multiple range test. Compared with the IVO group, in vitro-produced embryos had more (P = 0.055) degenerated conceptuses (IVO, 0%; IVPS, 18.5%; IVPSR, 20.6%). There were no differences (P > 0.05) in serum progesterone concentrations in recipients assigned to different treatments at Day 7. There was also no effect (P > 0.05) of treatment on progesterone levels in recipients with either male or female conceptuses at the time of transfer. Interestingly, heifers in the in vitro treatment groups had lower (P < 0.01) progesterone concentrations at Day 7 when no conceptus was recovered at Day 17 (IVPS, 2.1 ± 0.4 ng mL–1; IVPSR, 2.7 ± 0.4 ng mL–1; Least squares means ± standard error of the mean) compared with the IVO group (4.5 ± 0.6 ng mL–1). There was no difference in progesterone concentration between treatment groups for heifers with shorter conceptuses (≤194 mm). However, when longer (>194 mm) conceptuses were recovered, heifers with in vitro produced embryos had lower (P < 0.05) progesterone levels at Day 7 compared with those with in vivo produced embryos (IVPS, 2.2 ± 0.6 ng mL–1; IVPSR, 2.3 ± 0.5 ng mL–1; IVO, 3.9 ± 0.6 ng mL–1). In summary, serum progesterone concentrations in recipients at the time of transfer of in vivo- or in vitro-produced embryos were associated with conceptus development at Day 17 of gestation. Research supported by NC State University GAANN Biotechnology Fellowship (C. V. Barnwell) and the College of Veterinary Medicine.

scholarly journals Effect of follicular aspiration just before ovulation on corpus luteum characteristics, circulating progesterone concentrations and uterine receptivity in single-ovulating and superstimulated heifers

Reproduction ◽  
2012 ◽  
Vol 143 (5) ◽  
pp. 673-682 ◽  
Author(s):  
L O'Hara ◽  
S Scully ◽  
V Maillo ◽  
A K Kelly ◽  
P Duffy ◽  
...  
Keyword(s):  
Corpus Luteum ◽  
Uterine Receptivity ◽  
Subsequent Formation ◽  
Expected Time ◽  
Follicular Aspiration ◽  
Conceptus Development ◽  
Luteal Tissue ◽  
Follicle Aspiration ◽  
Length And Area

The aim of this study was to investigate, in unstimulated and superstimulated heifers, the effect of follicle aspiration just before ovulation on corpus luteum (CL) development, circulating progesterone (P4) concentrations and the ability of the uterus to support embryo development. Following follicle aspiration or ovulation timed from GNRH administration, CL development was assessed by daily ultrasonography, and CL function was assessed in terms of the capacity to produce P4 and the expression of genes involved in steroidogenesis in luteal tissue. The capacity of the uterine environment to support conceptus development was assessed following transfer and recovery of in vitro-produced embryos. Follicular aspiration just before the expected time of ovulation leads to a significant reduction in CL diameter, CL area and area of luteal tissue. This was associated with a decrease in circulating P4 in both unstimulated and superstimulated heifers. Follicle aspiration leads to a reduction in conceptus length and area on day 14 in unstimulated heifers only. Follicle aspiration leads to a reduction in the expression of LHCGR in luteal tissue from unstimulated heifers compared with those in which the CL formed after ovulation. Superstimulation significantly reduced the expression of STAR in luteal tissue in both ovulated and follicle-aspirated heifers. In conclusion, in stimulated and unstimulated heifers, aspiration of the preovulatory dominant follicle(s) just before expected ovulation interferes with the subsequent formation and function of the CL, in terms of size and P4 output and this, in turn, is associated with a reduced capacity of the uterus to support conceptus elongation in unstimulated heifers.

Effect of combined exogenous progesterone with luteotrophic support via equine chorionic gonadotrophin (eCG) on corpus luteum development, circulating progesterone concentrations and embryo development in cattle

2016 ◽  
Vol 28 (3) ◽  
pp. 269 ◽  
Author(s):  
L. O'Hara ◽  
N. Forde ◽  
P. Duffy ◽  
F. Randi ◽  
A. K. Kelly ◽  
...  
Keyword(s):  
Corpus Luteum ◽  
Embryo Quality ◽  
Single Injection ◽  
Chorionic Gonadotrophin ◽  
Serum Progesterone ◽  
Conceptus Development ◽  
Luteal Tissue ◽  
Exogenous Progesterone ◽  
Intravaginal Device

The aim was to examine the effect of a single intramuscular (i.m.) injection of equine chorionic gonadotrophin (eCG) on Day 3 after oestrus on corpus luteum (CL) development, circulating progesterone and conceptus development in cross-bred beef heifers. In Experiment 1, heifers received: (1) saline, or a single i.m. injection of eCG on Day 3 at (2) 250 IU (3) 500 IU (4) 750 IU or (5) 1000 IU. Administration of eCG resulted in increased luteal tissue area and progesterone and oestradiol concentrations compared with controls. In Experiment 2, heifers received (1) a progesterone-releasing intravaginal device (PRID Delta) from Day 3 to 5 or (2) a PRID Delta from Day 3 to 5 plus a single injection of 750 IU eCG on Day 3. In vitro-produced blastocysts (n = 10 per recipient) were transferred on Day 7 and heifers were slaughtered on Day 14 to assess conceptus development. Administration of eCG reduced the number of short cycles (6.3% vs 31.3%) and increased mean luteal tissue weight (P = 0.02). Insertion of a PRID Delta on Day 3 resulted in an elevation (P < 0.05) in serum progesterone until removal on Day 5. Administration of eCG at the time of PRID Delta insertion resulted in higher progesterone levels (P < 0.05) from Day 10 onwards. Conceptus dimensions were not affected. In conclusion, a single injection of eCG on Day 3 increased CL size and progesterone concentrations and, when given in conjunction with a progesterone-releasing device, appeared to reduce the number of short cycles, presumably due to its luteotrophic nature. The implications of the elevated oestradiol concentrations for embryo quality require further study.

scholarly journals Effects of a Nutritional Supplement on Cognitive Function in Aged Dogs and on Synaptic Function of Primary Cultured Neurons

Animals ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 393
Author(s):  
Maria Elena Pero ◽  
Laura Cortese ◽  
Vincenzo Mastellone ◽  
Raffaella Tudisco ◽  
Nadia Musco ◽  
...  
Keyword(s):  
Specific Effect ◽  
Nutritional Supplement ◽  
Synaptic Function ◽  
Negative Effects ◽  
In Vitro Effects ◽  
Navigation Test ◽  
Effects Of Aging ◽  
Neuronal Functions ◽  
Positive Effect

The objective of this research was to investigate the efficacy of DìSeniorTM, a nutraceutical formulated to improve cognitive functions in elderly dogs. To this purpose, some clinical and metabolic investigations and a spatial navigation test were performed in treated and untreated dogs. Moreover, the nutraceutical was also tested on primary hippocampal neuron cultures. Results showed no adverse effects on the dogs’ health and a positive effect on learning. In vitro effects on neuron cultures showed an increase in the level of cFOS in treated neurons compared with the vehicle, suggesting that DiSeniorTM has also a positive effect on neuronal functions. Overall, this study suggests that DiSeniorTM can exert a beneficial effect on aged dogs by preventing the negative effects of aging on cognition. Further studies are needed to assess the mechanisms by which it acts on neurons and the specific effect of the different components alone or combined.

146 DETRIMENTAL EFFECTS OF PROSTAGLANDIN F2α ON IN VITRO EMBRYO DEVELOPMENT IN BOVINE ARE INHIBITED BY A RECEPTOR ANTAGONIST

2008 ◽  
Vol 20 (1) ◽  
pp. 153 ◽  
Author(s):  
F. N. Scenna ◽  
J. L. Edwards ◽  
F. N. Schrick
Keyword(s):  
Prostaglandin F2α ◽  
Blastocyst Stage ◽  
Bovine Embryos ◽  
Negative Effects ◽  
In Vitro Development ◽  
Ann Arbor ◽  
Reproductive Techniques ◽  
Vitro Development ◽  
Cayman Chemical

Numerous studies have demonstrated negative effects of prostaglandin F2α (PGF2α) on bovine reproduction. Discovery of a PGF2α receptor (FPr) in bovine embryos (Scenna et al. 2006 Reprod. Fertil. Dev. 18, 180) allows for development of new therapeutic strategies to improve success of embryo transfer. Therefore, two experiments were performed to investigate the occurrence of any toxic effect of AL-8810 (Cayman Chemical Inc., Ann Arbor, MI, USA), an FPr antagonist, on in vitro development of bovine embryos. In Exp. 1, pre-compacted embryos were cultured in (1) 100 AL (100 nm AL-8810 in potassium simplex optimized medium with polyvinyl alcohol (KSOM-PVA); n = 94); (2) 50 AL (50 nm AL-8810 in KSOM-PVA; n = 94); (3) 25 AL (25 nm AL-8810 in KSOM-PVA; n = 94); and (4) CON (control: KSOM-PVA; n = 95). In Exp. 2, pre-compacted embryos were cultured in (1) 1000 AL (1000 nm AL-8810 in KSOM-PVA; n = 282); (2) 500 AL (500 nm AL-8810 in KSOM-PVA; n = 274); (3) 250 AL (250 nm AL-8810 in KSOM-PVA; n = 274); and (4) CON (control: KSOM-PVA; n = 278). Embryos remained in treatments until blastocyst assessment. Next, two experiments were performed to determine the efficiency of AL-8810 on preventing detrimental effects of PGF2α on pre-compacted embryos. In Exp. 3, pre-compacted embryos were cultured in (1) 100 AL (100 nm AL-8810 in KSOM-PVA; n = 121); (2) 10 PGF (10 ng mL–1 of PGF2α (Cayman Chemical Inc.) in KSOM-PVA; n = 91); (3) AL100+PGF (100 nm AL-8810 and 10 ng mL–1 of PGF2� in KSOM-PVA; n = 116); (4) CON (control: KSOM-PVA; n = 96). In Exp. 4, embryos were cultured in (1) 1000 AL (1000 nm AL-8810 in KSOM-PVA; n = 87); (2) 10 PGF (10 ng mL–1 of PGF2α in KSOM-PVA; n = 87); (3) AL1000+PGF (1000 nm AL-8810 and 10 ng mL–1 of PGF2α in KSOM-PVA; n = 84); (4) CON (control: KSOM-PVA; n = 84). In Exp. 3 and 4, embryos remained in treatments for 48 h when development to morula was assessed. Data for all experiments were analyzed using the GLIMMIX procedure of SAS (SAS Institute, Inc., Cary, NC, USA). For Exp. 1, results indicated that addition of 100, 50, and 25 nm did not compromise embryonic development to the blastocyst stage compared to controls (60.2%, 55.8%, 55.4%, and 49.9%, respectively). In addition, orthogonal contrasts indicated that 100 nm AL-8810 improved development to the blastocyst stage (100 AL = 61% v. CON = 50.6%, P = 0.01). Similarly for Exp. 2, 1000, 500, and 250 nm AL-8810 did not affect in vitro development to the blastocyst stage compared to controls (40%, 39%, 34.8%, and 37.7%, respectively). In Exp. 3 and 4, addition of 1000 nm AL-8810, but not 100 nm, to culture medium of pre-compacted embryos exposed to PGF2α increased the ability of embryos to undergo compaction 48 h later (1000 AL+PGF = 51% v. PGF = 40%; P = 0.05). In conclusion, AL-8810 at a concentration of 1000 nm inhibits detrimental effects of PGF2α on the development of pre-compacted bovine embryos and may prove beneficial for other assisted reproductive techniques in cattle. Funding was provided by Ultimate Genetics and the Tennessee Agricultural Experiment Station for completion of these studies.

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