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

Temporal changes in endometrial gene expression and protein localization of members of the IGF family in cattle: effects of progesterone and pregnancy

2012 ◽  
Vol 44 (2) ◽  
pp. 130-140 ◽  
Author(s):  
S. D. McCarthy ◽  
J. F. Roche ◽  
N. Forde
Keyword(s):  
Estrous Cycle ◽  
Cross Sections ◽  
Early Pregnancy ◽  
Protein Localization ◽  
Day Treatment ◽  
Transcript Abundance ◽  
Treatment Groups ◽  
Uterine Environment ◽  
To Receive ◽  
Intravaginal Device

In the study presented, the hypothesis that ligands of the insulin-like growth factor (IGF) family, as well as their binding proteins (BPs), are temporally regulated and are altered by elevated progesterone (P4) and/or pregnancy was tested. Heifers detected in standing estrus following synchronization ( n = 210, day 0), were artificially inseminated ( n = 140) or left as noninseminated cyclic controls ( n = 70). On day 3, half of each group were randomly assigned to receive a P4-releasing intravaginal device resulting in four treatment groups, pregnant and cyclic heifers with high and normal P4 concentrations on either day 5, 7, 13, or 16 of the estrous cycle/early pregnancy. Quantitative real-time PCR and immunohistochemistry were performed on endometrial homogenate and uterine cross sections to measure transcript abundance and protein localization respectively ( n = 5 per treatment per time point). No effect of day, treatment, or their interactions was observed for IGF2, IGFBP4, and - 5 ( P > 0.05). IGF1 and IGFBP6 expression decreased, while IGF1R and IGFBP2 expression increased ( P < 0.05) as the days of the cycle or pregnancy progressed. The expression of IGFBP2 was increased by elevated P4; in addition, localization of both IGF2 and IGFBP2 protein in the luminal and superficial glandular epithelium displayed a P4 × day interaction. In conclusion it is proposed that decreased IGF1 and IGFBP6 expression with a coordinate increase in IGF1R and IGFBP2 as the estrous cycle/early pregnancy progresses, along with other factors, are required to establish a uterine environment that promotes the growth and development of the conceptus prior to implantation. In addition, the increased protein abundance of both IGF2 and IGFBP2 observed in heifers supplemented with P4 contributes to the enhanced conceptus elongation observed in this model.

scholarly journals 150 ENVIRONMENT OF THE EARLY EMBRYO AND ITS EFFECT ON DEVELOPMENT AND POSTNATAL LIFE

2005 ◽  
Vol 17 (2) ◽  
pp. 225
Author(s):  
A. Watkins ◽  
A. Wilkins ◽  
T. Papenbrock ◽  
C. Osmond ◽  
M. Hanson ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Systolic Blood Pressure ◽  
Embryo Transfer ◽  
Litter Size ◽  
Early Embryo ◽  
Blastocyst Development ◽  
Treatment Groups ◽  
Elevated Systolic Blood Pressure

We have investigated the impact of mouse early embryo in vitro culture environment on (a) short-term blastocyst development and (b) long-term postnatal growth and physiology after embryo transfer. In vitro-developed blastocysts, cultured from the 2-cell stage, had reduced inner cell mass (ICM) and trophectoderm (TE) cell numbers when compared to in vivo-derived blastocysts at 96 h post-hCG (n = 13–39, P < 0.05). Despite the retardation in blastocyst development, the ICM:TE ratio was equivalent in both treatment groups. Using embryo transfer techniques, we compared the postnatal development of embryos cultured in vitro from the 2-cell to the blastocyst stage (termed “in vitro” mice) with offspring generated from blastocysts developed in vivo, but which also underwent embryo transfer (termed “in vivo” mice). These two treatment groups were in turn compared with mice derived from naturally mated mothers, which had their mean litter size at birth adjusted to a size comparable with that of the in vitro and in vivo mice (a mean of 6 animals) and which had not been transferred. All data were analyzed using a multilevel random effects regression model which took into account between-mother and within-mother variation in litter size for parameters measured from individual animals. No significant differences in birth weight were observed between in vitro and in vivo offspring. However, in vitro offspring were significantly lighter than in vivo offspring in a gender-dependent manner at 2 weeks of age (males, P = 0.009) and at 6 and 11 weeks of age (females, P = 0.037 and 0.035, respectively). In addition, at 4 weeks of age, the in vivo males became significantly lighter when compared to the naturally mated males (P = 0.034). At 8 weeks of age, the in vivo females had a significantly elevated systolic blood pressure when compared to the in vitro females (P = 0.003); however, at 21 weeks of age, both in vitro males and females had a significantly elevated blood pressure when compared to in vivo offspring (P < 0.003). At 8, 15, and 21 weeks of age, offspring derived from transferred embryos developed with significantly elevated systolic blood pressure when compared to non-embryo transfer offspring (P < 0.05). No significant differences in serum angiotensin-converting enzyme activity (a potent regulator of systolic blood pressure) was observed between the treatment groups. Significantly altered liver:body weight ratios were observed between the in vitro and in vivo males, and between the in vitro and the naturally mated (6) females (P < 0.038). All of the above data are independent of litter size. These data support the hypothesis that early embryo environment can influence postnatal growth and cardiovascular physiology. This research was funded by an MRC research grant to TPF, and by a DOHaD studentship.

scholarly journals Embryo transfer as an option to improve fertility in repeat breeder dairy cows

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Arkadiusz Nowicki
Keyword(s):  
Dairy Cows ◽  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Oocyte Quality ◽  
Poor Quality ◽  
Early Embryo ◽  
Reproductive Disorder ◽  
Uterine Environment ◽  
Repeat Breeder

Abstract Repeat breeding is a serious reproductive disorder in dairy cattle. The causes of repeat breeding are multifactorial and there are two main mechanisms: failure of fertilisation or early embryo death, mainly due to poor quality of oocytes and an inadequate uterine environment. Many methods have been used to increase the pregnancy rate for repeat breeder cows, such as intrauterine infusion of antibacterial agents or antibiotics, hormonal treatments for oestrus synchronisation and induction of ovulation, and progesterone supplementation or induction of accessory corpus luteum; however, the results were inconsistent between studies. Embryo transfer (ET) has the capability to minimalise the effects of poor oocyte quality and unfavourable uterine environments on early embryo development during the first seven days after ovulation in repeat breeder cows, and several studies showed that ET significantly improved the pregnancy rate in this group of animals. Thus, ET can be considered an option to increase the conception rate in repeat breeder dairy cows.

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.

107 FACTORS THAT INFLUENCE FERTILITY IN AN IVF EMBRYO TRANSFER PROGRAM IN DAIRY HEIFERS

2016 ◽  
Vol 28 (2) ◽  
pp. 183 ◽  
Author(s):  
L. C. Carrenho-Sala ◽  
R. V. Sala ◽  
M. Fosado ◽  
D. C. Pereira ◽  
S. Garcia ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Pregnancy Loss ◽  
Embryo Quality ◽  
Prostaglandin F2α ◽  
Transfer Program ◽  
Dairy Heifers ◽  
Embryo Transfer Program ◽  
Embryo Stage ◽  
Major Factors

A retrospective study was performed to evaluate factors that influence pregnancy per embryo transfer (P/ET) in an IVF-embryo transfer program. A total of 5026 fresh in vitro-produced embryos were transferred during 2014 and evaluated for effects of embryo quality, embryo stage, size of corpus luteum (CL; 18–19.9 mm or ≥20 mm), interval from GnRH to embryo transfer, number of previous embryo transfer (0, 1, 2, 3, ≥4); and interaction of embryo stage and interval from GnRH to embryo transfer. One group (n = 850) had detection of oestrus after prostaglandin F2α application but most heifers (n = 4176) received fixed timed embryo transfer after a 5-day CIDR-Synch protocol: Day –8 CIDR inserted; Day –3 CIDR removed and prostaglandin F2α; Day –2 prostaglandin F2α; Day 0 GnRH. Ultrasound was performed on Day 6 after GnRH or oestrus to measure CL size and on Day 32 and 60 to determine pregnancy. Data for P/ET were analysed by logistic regression (LOGISTIC procedure, SAS 9.4). Embryo quality influenced P/ET at Day 32 [Grade 1 48.4% (1273/2631) v. Grade 2 37.6% (900/2395); P < 0.01] and at Day 60 [Grade 1 38.9% (1023/2631) v. Grade 2 29.0% (694/2395); P < 0.01], and altered pregnancy loss [Grade 1 19.6% (250/1273) v. Grade 2 22.9% (206/900); P = 0.03]. Stage of the embryo also had an effect on P/ET at Day 32 [Stage 6 35.5%a (582/1641), Stage 7 46.3%b (1431/3092), and Stage 8 54.6%c (160/293); P < 0.01] and at Day 60 [Stage 6 28.2%a (462/1641), Stage 7 36.6%b (1131/3092), and Stage 8 41.6%b (122/293); P < 0.01], but did not affect pregnancy loss (P = 0.22). Interestingly, interval from GnRH (or oestrus) until embryo transfer did not affect P/ET at Day 32 (P = 0.10), 60 (P = 0.23), or pregnancy loss (P = 0.3), nor was there an interaction between interval and embryo stage at Day 32 (P = 0.77), 60 (P = 0.96) or pregnancy loss (P = 0.55). As shown in Table 1, embryo stage 6 was always the lowest and stage 8 always the greatest P/ET regardless of interval from GnRH to embryo transfer. Size of CL also did not affect P/ET at Day 32 (P = 0.09), 60 (P = 0.21), or pregnancy loss (P = 0.90). Number of previous embryo transfer also did not alter P/ET at Day 32 [0 = 43.3% (886/2046), 1 = 44.1% (639/1450), 2 = 43.4% (444/1024), 3 = 42.6% (146/343), and ≥4 = 35.6% (58/163); P = 0.33] or 60 (P = 0.51) or pregnancy loss (P = 0.12). In conclusion, embryo stage and quality are the major factors that impacted P/ET in this study, with surprisingly little effect of interval from GnRH to embryo transfer, size of the CL, and number of previous embryo transfer. Thus, recipient programs for IVF-embryo transfer can be designed with substantial flexibility. Table 1.Effect of embryo stage and recipient synchrony on pregnancies per embryo transfer on Day 32 in recipient dairy heifers

160 CONCEPTION RATES FOLLOWING TREATMENT OF LACTATING HOLSTEIN RECIPIENTS WITH A GONADOTROPIN RELEASING HORMONE (GnRH) ANALOGUE AT THE TIME OF TRANSFER OF OVUM PICK-UP/IVF-DERIVED EMBRYOS

2013 ◽  
Vol 25 (1) ◽  
pp. 228
Author(s):  
T. L. C. Pinto ◽  
J. N. S. Sales ◽  
R. R. Carvalho ◽  
T. M. França ◽  
J. C. Souza
Keyword(s):  
Dairy Cows ◽  
Embryo Transfer ◽  
Management Tool ◽  
Gnrh Analogue ◽  
Gnrh Analogues ◽  
Treatment Groups ◽  
Lactating Dairy Cows ◽  
Conception Rates ◽  
Day Of Embryo Transfer

The use of lactating dairy cows as ovum pick-up (OPU)/IVF-derived embryo recipients in large-scale embryo transfer programs may be limited by the effects of low progesterone concentrations on the uterine environment and subsequent embryo development. It was hypothesized that the injection of a GnRH analogue on the day of embryo transfer would induce ovulation and formation of an accessory corpus luteum, increasing progesterone concentrations and, as a result, conception rates. An experiment was designed to evaluate the effects of two different GnRH analogues injected IM on the day of embryo transfer on conception rates of lactating Holstein recipients. Oestrus was not synchronized and was detected continuously by multiple observers during the day and in the evening until midnight. Recipient days in milk varied from 45 to 150, daily milk production ranged from 20 to 45 kg, body condition scores and age ranged from 2.5 to 4.5 and 2.5 to 5.5 years, respectively. Herd pregnancy rates after the first artificial insemination ranged from 15% to 70%, considering the period the experiment was conducted. Embryos were produced by standard in vitro techniques following OPU on Holstein donors. Lactating Holstein recipients (n = 224) were allocated randomly to one of three treatment groups 7 days after detected oestrus: Control (n = 77) = vehicle; Buserelin (Sincroforte®, Ouro Fino, Sao Paulo, Brazil; n = 75) = 10 µg; and Deslorelin (Sincrorrelin®, Ouro Fino; n = 72) = 750 µg. Embryos were transferred nonsurgically 6 to 8 days after observed oestrus. Pregnancy was detected by ultrasonography between 62 and 72 days after embryo transfer. Percent pregnant data were analyzed as a binomial distribution under the GENMOD procedure of SAS (SAS Institute Inc., Cary, NC, USA). Conception rates were similar (P = 0.13) between Control (28%, 22/77), Buserelin (24%, 18/75), and Deslorelin (38%, 28/72) treatment groups. These data demonstrate that conception rates from in vitro produced embryos transferred to lactating dairy cows are not improved by treatment with a GnRH analogue on the day of transfer. Although not critically tested, results indicate that adequate conception rates may be obtained in commercial dairy operations from OPU/IVF-derived embryos, adding an important management tool for reproduction and animal breeding enhancement.

47 A New Device and Method for Successful Vitrification of In Vitro-Produced Ovine Embryos

2018 ◽  
Vol 30 (1) ◽  
pp. 163
Author(s):  
S. Ledda ◽  
J. M. Kelly ◽  
S. K. Walker ◽  
Y. Natan ◽  
A. Arav
Keyword(s):  
Survival Rate ◽  
Embryo Transfer ◽  
Blastocyst Stage ◽  
Embryo Cryopreservation ◽  
Control Group ◽  
Hatching Rate ◽  
High Survival ◽  
Embryo Survival ◽  
New Device

To advance the use of embryo vitrification technology in veterinary practice, we developed a system in which embryo vitrification, warming, and dilution can be performed within a straw. An in-straw embryo cryopreservation method reduces the need for equipment and technical skills and can facilitate direct embryo transfer to the uterus. This study proposes the use of a new device named “Sarah” that is designed to permit all in-straw embryo cryopreservation procedures. Ovine in vitro-produced (IVP) embryos were vitrified at either early blastocyst stage (EB, n = 65, 6 days post-IVF) or fully expanded blastocyst stage (FB, n = 168, 7 days post-IVF). The vitrification procedure using Sarah constituted a 0.25-mL straw with a capsule having 50-µm pores inserted at one end. Embryos at each stage (EB and FB) were divided into 2 subgroups and vitrified by 1 of 2 methods: (1) multi-step (MS) group-a straw containing 2 embryos was sequentially loaded vertically into 1.5-mL tubes containing 6 different vitrification solutions: 10, 20, 40, 60, 80, or 100% ES (with 100% ES being 7.5% DMSO +7.5% EG + 20% FCS in TCM-199; 90 s each step) followed by 30 s each in 75 and 100% VS (100% VS being 18% DMSO +18% EG + 0.5 M trehalose + BSA in TCM-199); and (2) two-step (TS) group-the straw (2 embryos/straw) was loaded with 100% of ES (5 min), followed by 100% VS solution for 30 s. For both methods, at the end of the preparation steps, the straws were plunged directly into liquid N2. Non-vitrified embryos were maintained in in vitro culture as a control group (n = 102). The warming procedure consisted of placing the straws directly into 5-mL tubes containing 100, 50, 25% WS (WS = 1 M sucrose in TCM-199+ 20% FCS) at 38.6°C (for first solution) and at room temperature for all the rest (5 min each), before being placed into the holding medium. Embryos were recovered from the straws, incubated at 38.6 C in 5% CO2 in air in TCM 199 + 5% FCS, and evaluated for blastocoel re-expansion, embryo survival, and hatching rate at 2, 14, 48 h post-warming. Blastocyst re-expansion (2 h) after warming increased as the developmental stage progressed and was not affected by the vitrification method. In fact, it was significantly (P < 0.05) higher for FB vitrified in the MS and TS methods (77.90% and 71.25%, respectively) compared with the EB method (62.5% and 48.50%, respectively). At 24 h, survival rate of vitrified FB was significantly higher (P < 0.05) in the MS system (95.35%) compared with those in TS (86.25%). Survival rates of FB embryos for both methods (MS and TS) were significantly higher (P < 0.001) than EB embryos vitrified in MS (56.25%) and TS (56.55) methods. After 48 h of culture, the hatching rate for FB vitrified in the MS system (87.21%) was comparable with TS (77.5%) and control (85.3%) groups but significantly higher (P < 0.001) than vitrified EB in MS (43.75%) and TS (36.36%). In conclusion, we showed that a high survival rate of IVP embryos can be achieved by this new in-straw vitrification and warming device (“Sarah”), with hatching rates in vitro comparable with that of control fresh embryos. This method has the potential for use in direct embryo transfer in field conditions.

94 EFFECTS OF 6- OR 12-HOUR CULTURE IN A Micro Q STRAW INCUBATOR ON DEVELOPMENT OF IN VITRO-PRODUCED BOVINE EMBRYOS

2016 ◽  
Vol 28 (2) ◽  
pp. 177
Author(s):  
C. R. Looney ◽  
J. H. Pryor ◽  
M. Snyder ◽  
A. Ilercil ◽  
C. R. Long
Keyword(s):  
Embryo Transfer ◽  
Uv Light ◽  
Tween 20 ◽  
Treatment Groups ◽  
Cell Counts ◽  
Stage 4 ◽  
Embryo Stage ◽  
Transfer Services ◽  
In Transit

Transporting in vitro-produced (IVP) embryos can be challenging when an embryo transfer destination is more than 6 h away or electricity is not available on site to unload embryos for transfer. The objective of this study was to determine if development rates would be compromised for Day 6.5 IVP embryos when placed in warmed Vigro holding medium (Vetoquinol, Pullman, WA, USA) loaded and plugged into 1/4 cc straws (Professional Embryo Transfer Services, Canton, TX, USA) for a period of either 6 or 12 h in a 38.5°C Micro Q straw block incubator (Micro Q iQ1T 64). Bovine oocytes were shipped and matured in transit from a commercial abattoir (DeSoto Biosciences, Seymour, TN, USA), fertilized (IVF = Day 0) with frozen-thawed semen, and cultured in Bovine Evolve (Zenith Biotech, Guilford, CT, USA) supplemented with 4 mg mL–1 BSA (Probumin, EMD Millipore, Norcross, GA, USA) under oil in a 5% CO2, 5%O2, 90% N2 humidified incubator (Pryor et al. 2011 Theriogenology 75, 24–33). Cleavage rates of 87.7% (664/757) from three replicates produced 273 (36.0%) viable embryos on Day 6.5 post-IVF, which were evenly distributed by IETS stage (4–7) and grade (1 and 2) into three treatment groups (0 = control, 6 or 12 h straw incubation) before in vitro culture for an additional 24 h. For each replicate, the average embryo stage was calculated by multiplying the number of embryos in each treatment by their IETS stage and dividing by total embryos per group. The change in stage for each treatment was calculated by subtracting the initial average stage from the final average stage on Day 8. Grade 1 and 2 embryos at stage 6–8 were counted and used to calculate total viable rates. Day 8 (post-IVF) embryos were fixed in cold methanol, washed in PBS/0.1%Tween 20, mounted in 10 μg mL–1 Hoechst 33342/glycerol and viewed under UV light to count nuclei. Percentage data were transformed using arcsine square root function before analysis, and means were compared using a one-way ANOVA and Tukey’s HSD. Although viability decreased with increasing time in straw incubation, there were no statistical differences between control, 6 and 12 h treatments for total viable rates (90.8, 80.3, and 70.8%, respectively). Average embryo stage on Day 8 for control, 6 and 12 h (7.0 ± 0.66, 6.6 ± 0.24, and 6.2 ± 0.30 s.e.m., respectively) was not different, but tended to be higher in control (P = 0.08). The change in stage, however, was different between control and 12 h (1.46 ± 0.33 and 0.66 ± 0.24, respectively; P < 0.05). Likewise, cell numbers were greater in control and 6 h embryos compared with 12 h straw incubation (149.8 ± 9.14, 138.7 ± 7.94, and 101.8 ± 5.29; n = 47, 50, and 46, respectively P < 0.01). In conclusion, 6.5 day IVP embryos held in warm Vigro holding medium for 12 h in 1/4 cc straws fail to develop at the same rate and incurred lower cell counts than either control or 6 h treatments. Further research to evaluate pregnancy rates following transfer and utilising different incubation or media and/or temperature is warranted to further evaluate the utility of in straw incubation for extended periods of time.

164 The Origin of Oocyte, In Vitro-Matured Oocyte With/Without Super-Stimulation, and In Vivo-Matured Oocyte Influence the Timing of Cleavage in Early Embryo and Oxygen Consumption of Blastocyst After IVF in Japanese Black Cow

2018 ◽  
Vol 30 (1) ◽  
pp. 221
Author(s):  
T. Yamanouchi ◽  
H. Matsuda ◽  
M. Ohtake ◽  
Y. Ogata ◽  
Y. Aikawa ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Oxygen Consumption ◽  
Prostaglandin F2α ◽  
Early Embryo ◽  
Developmental Competence ◽  
Induction Treatment ◽  
Time Interval ◽  
Matured Oocyte

It has been reported that in vitro- and in vivo-matured oocyte obtained from fully growth follicles have high developmental competence. Furthermore, the timing of cleavage in early embryo after IVF affect pregnancy success after embryo transfer. It is still unknown whether origin of oocyte affects the timing of cleavage. In this study, we examined the influence of oocyte origin on cleavage timing of early embryo after IVF. Japanese Black cows were used as donors. Oocytes derived from non-stimulation follicles (control: CON), fully grown follicles after super-stimulation treatment (SST) and follicles just before ovulation after ovulation-induction treatment (in vivo-matured oocyte: VIVO) were obtained by ovum pick-up (OPU). In the CON group, OPU was conducted on arbitrary days except oestrus. In SST group, dominant follicles were aspirated and a CIDR was inserted into the vagina on Day 0, and then FSH was injected twice a day from the evening of Day 1 to the morning of Day 5 with decreasing doses in total 20 AU. In the evening of Day 4, prostaglandin F2α (0.5 mg of cloprostenol) was administered. On Day 6, SST oocytes were collected after CIDR withdrawl. In the VIVO group, the treatment was carried out as SST until prostaglandin F2α administration, and then CIDR withdrawal and administration of gonadotropin-releasing hormone (GnRH, 0.2 mg of fertirelin acetate) performed on the evening of Day 4 and morning of Day 5, respectively. The VIVO oocytes were collected at 25 to 26 h after GnRH. The CON and SST oocytes were inseminated after 20 to 22 h of IVM, and VIVO oocytes were inseminated at 30 h after GnRH, with 3 × 106 sperm mL−1, respectively. After 6 h of IVF, presumptive zygotes were individually cultured for 168 h, using a well-of-the-well dish (Dai-Nippon-Print, Japan) and were observed by time-lapse cinematography (CCM-4MZS; Astec, Japan) to analyse the cleavage timing of embryos. Oxygen consumption (O2) was measured in blastocysts on 168 hpi with a scaning electrochemical microscopy system (HV-405SP; Hokuto Denko, Japan). Statistical analysis was carried out by Steel-Dwass test for the timing of cleavage and Tukey-Kramer test for O2. In CON (n = 15), SST (n = 25), and VIVO (n = 36), the time of first cleavage was 27.5, 29.1, and 26.1 hpi, that of second cleavage was 38.9, 40.3, and 36.0 hpi, and that of third cleavage was 48.5, 46.1, and 45.9 hpi, respectively. These cleavage times were shorter in VIVO than in CON and SST (P < 0.01). The time interval between first and second cleavage (2nd cell cycle) was shorter in VIVO (10.1; P < 0.01) than CON (11.4) and SST (11.2). The time interval between second and third (3rd cell cycle) were shorter (P < 0.01) in SST (9.4) than in VIVO (10.1), and in VIVO than in CON (10.2), respectively. Consumption of O2 was lower (P < 0.01) in CON (0.61 × 10−14 mol s−1) than in SST (0.94 × 10−14 mol s−1) and VIVO (0.94 × 10−14 mol s−1). These results suggest that the origin of oocyte influences the length of cell cycle and O2 consumption of blastocyst producted in vitro.

Effect of plasma urea concentration at the time of insemination or embryo transfer on pregnancy rate in cattle

2001 ◽  
Vol 26 (2) ◽  
pp. 367-370 ◽  
Author(s):  
V.P. Gath ◽  
J. Fahey ◽  
S.E.M. Snijders ◽  
D. O'Callaghan
Keyword(s):  
Pregnancy Rate ◽  
Embryo Transfer ◽  
High Energy ◽  
Subsequent Pregnancy ◽  
Plasma Urea ◽  
Retrospective Comparison ◽  
Significant Difference ◽  
Uterine Environment ◽  
Plasma Urea Concentration

AbstractPlasma urea concentrations have been used as a diagnostic tool in the investigation of reproductive performance in cattle. Data were compiled from three recent studies on bovine fertility and a retrospective comparison of plasma urea concentrations was made between those animals that conceived to an insemination or embryo transfer. In studies I and 2 plasma urea concentrations around the time of insemination were determined. Pregnancies were diagnosed using ultrasonography 35 days later. There was no significant difference between the mean plasma urea concentrations around the time of insemination in the cattle subsequently diagnosed pregnant or not pregnant. In study 3, in vitro produced good quality embryos were transferred into three groups of beef heifers. The three groups were allocated to diets of high energy / high urea, high energy / no urea and low energy / high urea. The plasma urea concentrations at the time of embryo transfer were different between the three groups. However, the pregnancy rates 28 days post transfer, were not significantly different between the three groups. This suggests that the previously reported effects of high protein diets on fertility are not solely due to disruptive effects on the uterine environment. The main effect of urea on fertility may be on oocyte development within the follicle. Overall, these results indicate that measurement of plasma urea concentrations in individual animals around the time of insemination or embryo transfer is not a useful predictor of subsequent pregnancy rate.

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