264 EFFECT OF FROZEN SEMEN BATCH ON THE IN VITRO PRODUCTION OF BOVINE EMBRYOS

2010 ◽  
Vol 22 (1) ◽  
pp. 289
Author(s):  
M. B. Fernandes ◽  
T. L. G. Torregrossa ◽  
R. B. Prado ◽  
R. A. Vila ◽  
F. P. Elias ◽  
...  

Within an in vitro production controlled system, bulls differ with respect to their semen potential in generating embryos when the variables of maternal effect are minimized (Marquant-le-Guienne and Humblot 1992 Ann. Zootech. 41, 361-370). We have tested the hypothesis that even with this variation among bulls, there is also an intra-bull variation, according to the frozen semen batch used in the in vitro fertilization, identified with the date of ejaculate and its freezing. In an embryo commercial production system, over 12 months, 10 619 viable oocytes were obtained by ultrasound-guided follicular aspiration from 642 Nelore cows (Bos indicus). The oocytes were matured in vitro for 24 h in TCM-199 supplemented with 0.5 μg mL-1 FSH, 50 μg mL-1 LH, and 10% fetal bovine serum. They were then inseminated for 18 hours in IVF-TALP medium, using the semen from 4 bulls (A to D) subdivided into 4 frozen batches (I to IV) and selected by 45/90% Percoll gradient. Putative zygotes surrounded in cumulus cells were transferred in CR2aa medium drops (Rosenkrans and First 1994 J. Anim. Sci. 72, 434-437) for 163 h at 39°C in a humidified atmosphere of 5% CO2 in air. The oocyte distribution, the total number of blastocysts, and the embryo development rate by each bull and respective batch are described in Table 1. The chi-square test was measured with a significance level of P < 0.05 and showed that there is a difference between the used batches of each bull regarding the development rate of blastocysts 163 h after IVF Therefore, there is intra-bull variation in the ability to develop in vitro embryos according to the batch of frozen semen. Table 1.Viable oocytes (VO), total blastocysts (TB), and embryo development rate (%E) by bull and batch used in IVF

2009 ◽  
Vol 21 (1) ◽  
pp. 209
Author(s):  
Y. Serita ◽  
C. Kubota ◽  
T. Kojima

This study tested whether embryo development yield using in vitro fertilization (IVF) could be improved by rocking cultures. Bovine ovaries were obtained at a slaughterhouse and transported to the laboratory within 6 h. Cumulus–oocyte complexes were collected and 20–25 were transferred in 100-μL drops of TCM-199 containing 10% fetal bovine serum and antibiotics under paraffin oil. Maturation was for 20–24 h at 38.5°C under 5% CO2 and 95% air in a humid atmosphere (IVM). In vitro fertilization was carried out for 6 h using frozen–thawed sperm from a single bull in modified Brackett and Oliphant (BO) medium. Presumptive zygotes were cultured in CR1aa supplemented with 10 mg mL–1 of BSA or 5% FBS for 9 d at 38.5°C under 5% CO2, 5% O2, and 90% N2 in a humid atmosphere (IVC). Rocking was performed to a height of 6 cm every 7 s using a Profile Rocker (New Brunswick Scientific Co., Edison, NJ, USA) in an incubator. Dishes were placed at a 15-cm distance from the fulcrum of the rocker. The conventional method (no rocking) served as a control, and every experiment was replicated 3 times. For Experiment 1, the effect of the period of rocking on developmental competence was examined when COC or zygotes were subjected to rocking for IVM, IVF, or IVC (IVM-move, IVF-move, and IVC-move). There were no significant differences in rates of oocyte maturation, cleavage, and development for IVM-move v. the control, or for rate of development between IVC-move and the control. However, the rate of fertilization for IVF-move was higher than that of the control (88.9 v. 67.5%; P < 0.01), and the rate of development was higher for IVF-move than for the control (39.0 v. 25.7%; P < 0.05). For Experiment 2, the effect of rocking frequency during IVF on development was determined. The IVF cultures were rocked every 7, 3.5, and 1.5 s (IVF-1move, IVF-2move, IVF-3move). The rates of cleavage on IVF-1move, IVF-2move, IVF-3move, and the control were 74.3, 69.8, 68.8, and 60.4%, and the rates of development were 39.0, 48.3, 26.2, and 25.7%, respectively. The rates of development on IVF-1move and IVF-2move were significantly different from the control and IVF-3move (P < 0.01). These results showed that rocking during IVF improved fertilization and embryo yield, and that frequency of rocking affected embryo development.


SPERMOVA ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 67-72
Author(s):  
Mijail Contreras Huamani ◽  
◽  
Mary Naveros ◽  
Cesar Olaguivel

The objective of this research was to evaluate the effect of the use of two sperm selection techniques for in vitro production of alpaca embryos. The ovaries and testis were collected from the local slaughterhouse and transport to 37 ° C in saline solution (0.9%) supplemented with gentamicin. Quality I, II and II oocytes were incubated in a maturation medium for 32 h at 38.5 ° C and 5% O2 and 5% CO2. For in vitro fertilization, sperm from the epididymis were selected using the Percoll gradient and Swim up technique. 18h after the oocytes were incubated with the sperm, these were denuded from the cumulus cells and cultured in SOFaa culture medium for 7 days. Morula and blastocyst rate and their morphological quality are evaluated at day 7 of culture. From a total of 370 ovaries, 1,137 oocytes were recovered, making an average of 3.6 oocytes / ovary. After the maturation and fertilization process and in vitro culture, the blastocyst rate was 8.43 ± 6.04% and 3.89 ± 1.75%, for oocytes fertilized with sperm selected with Percoll gradient and Swim up, respectively, not finding significant statistical differences (p> 0.05), between the groups. In conclusion, the in vitro fertilization of alpaca oocytes with spermatozoa selected with two selection techniques (percoll and swim up) did not significantly influence the quantity and quality of morulae and blastocysts at day 7 of embryo culture.


2007 ◽  
Vol 19 (1) ◽  
pp. 298 ◽  
Author(s):  
V. Malcolm ◽  
M. Marfil ◽  
M. Calvi ◽  
F. Rigali ◽  
M. Pugliese ◽  
...  

Sperm sexing has become a world-wide technology, now available in many countries. The method has been incorporated into many reproductive technologies such as embryo production (Zhang et al. 2003 Theriogenology 60, 1657–1663), but sex-sorting is limited when bulls are located far from sorters or when only frozen semen is available. Previous studies on sexing frozen–thawed spermatozoa have been done in rams, which resulted in retention of the spermatozoan functional capacities (Hollinshead et al. 2004 Reproduction 127, 557–568). In vitro characteristics were assessed in bulls after sexing of thawed sperm (Hollinshead et al. 2004 Theriogenology 62, 958–968); however, the fertilizing capacity of frozen–thawed sex-sorted (FTSS) spermatozoa was not tested. The aim of the present study was to compare cleavage and embryo development rate among frozen–thawed (FT), sex-sorted frozen–thawed (SSFT), and FTSS bull spermatozoa. For FT, sperm were diluted to a final concentration of 60 × 106 sperm/mL, packaged in 0.5-mL straws, and frozen. In SSFT, spermatozoa were sex-sorted by flow cytometry following Schenk protocols (1999 Theriogenology 52, 1375–1391). Three × 106 spermatozoa were packaged into 0.25-mL straws and frozen. The final treatment (FTSS) consisted of thawing 6 to 10 frozen straws of 4 different bulls containing an average of 25 × 106 spermatozoa and centrifuging at 600g for 15 min at 21°C to extract cryodiluent. Spermatozoa were diluted and stained with Hoechst 33342 (stain concentration of 112.5 µM, the same used for SSFT treatment) following Schenk sexed-semen protocols (1999), sex-sorted by a flow cytometer, and collected in Tris-base extender containing 20% egg yolk. For each ejaculate frozen–thawed, SSFT and FTSS spermatozoa were prepared for oocyte in vitro fertilization. Also, semen from a bull routinely used as a control in the laboratory was added for a better comparison of results. Oocytes from a slaughterhouse were processed following standard in vitro fertilization procedures (Ferré 2002 Theriogenology 57, 664) 4 times for each bull, and comparison was made between treatments. Results were analyzed by ANOVA. No significant differences were observed among bulls (data not shown) (P &gt; 0.05). Although embryo development rate was statistically different between sexed and non-sexed groups (P &lt; 0.05), results showed that frozen–thawed bull spermatozoa can be sex-sorted and used for in vitro fertilization with comparable developmental rates comparable to those when frozen sexed semen is used (Table 1). This opens a new commercial window for cases where pre-selected sexed embryos from bulls that are not in AI centers are desired, also giving an opportunity for dead bulls. Nevertheless, since a large number of straws are necessary, further studies must be carried out to make this procedure more efficient and economically profitable. Table 1. Results of cleavage and embryo development rates between spermatozoa treatments


2010 ◽  
Vol 22 (1) ◽  
pp. 305
Author(s):  
A. Renzi ◽  
F. P. Elias ◽  
R. A. Vila ◽  
R. B. Lôbo

Reproductive biotechnology is growing worldwide as one of the most important tools of cattle breeding because it accelerates the process of genetic improvement. Most of the embryos produced are obtained using frozen semen from different AI centers. During freezing and thawing of semen, the sperm can be damaged by the rapid and dramatic changes in the physicochemical conditions that occur during cooling and ice formation. It has previously been described that bad management of frozen semen can result in reduced fertilization. This study investigated the influence of different central bull stations on the development of in vitro-produced bovine embryos. We compared semen of 154 Nelore bulls, used for IVF, from 8 different central bull stations (all of which used the same cryopreservation protocol) in the development of blastocysts. The in vitro production of embryos was performed as described: oocytes were collected from the slaughterhouse and matured in TCM-199 + 10% fetal calf serum (FCS) +0.5 μg mL-1 FSH + 50 μg mL-1 LH+ 1 μg mL-1 estradiol, for 24 hat 38.5°C in 5%CO2 in atmospheric air. Viable spermatozoids were obtained by centrifugation in Percoll gradient (45 and 90%), and used for IVF in a concentration of 2 million spermatozoa per mL in TALP + 10 μg mL-1 of heparin medium. After 12 h, the presumptive zygotes were transferred to a CR2+ 10% FCS medium and co-cultured with cumulus cells. After 168 h of IVF, we evaluated the number and stage of cleaved embryos produced with the semen of each bull. Statistical analyses were performed by using the chi-square test. Our results suggest that there are differences among distinct central bull stations in the proportion of embryos that developed into blastocysts and the different stages they hatched. FAPESP, CNPq, PROEX, FAEPA.


2017 ◽  
Vol 29 (1) ◽  
pp. 180
Author(s):  
C. C. Chase ◽  
R. A. Cushman ◽  
A. K. McNeel ◽  
E. C. Wright-Johnson ◽  
G. A. Perry ◽  
...  

Our objective has been to compare the IVF and in vitro production (IVP) of embryos from low and high antral follicle count (AFC) heifers. This is the fourth year of the study with years 1 to 3 reported individually. For this report, we add data for the fourth year and present a combined analysis (years 1 to 4) for the first time. Each year, AFC was determined on ~120 Angus heifers using transrectal ultrasonography. Ten heifers with the lowest AFC and 10 heifers with the highest AFC and all with evidence of oestrous cyclicity were synchronized with two 5-mL injections of PGF2α 11 days apart. Half were harvested on Day 5 to 6 and half on Day 15 to 16 of the oestrous cycle. The IVF procedure was slightly modified each year. For year 4, the IVF procedure included protocols for semi-defined media and was as described (IVP Protocol, P. J. Hansen’s Laboratory, University of Florida). Cumulus-oocyte complexes (COC) from follicles less than 8 mm in diameter were cultured in maturation medium (5% CO2; 38.5°C) for 24 h. Matured COC were fertilized using thawed frozen semen from a bull that was purified using isolate. Motile spermatozoa were added to COC in fertilization medium at a final concentration of 1 × 106 spermatozoa per mL. About 24 h later, presumptive zygotes were placed in micro drops of development medium under oil, and cultured (5% CO2; 5% O2; balance N2; 38.5°C). On Day 3 and 8 after fertilization, cleavage and blastocyst development rates, respectively, were assessed. Data were analysed using the MIXED procedure of SAS (SAS Institute Inc., Cary, NC, USA) and the model included the effects of year (1 to 4), group (high or low AFC), and their interaction. The year × group interaction was not significant (P > 0.10). Low AFC heifers, compared with high AFC heifers, had fewer numbers of COC (P < 0.0001; 12.8 ± 1.83 v. 31.9 ± 1.86), fewer numbers of COC that cleaved (P < 0.0001; 8.0 ± 1.38 v. 21.6 ± 1.40), and fewer numbers of COC that developed to the blastocyst stage (P < 0.0001; 1.7 ± 0.58 v. 5.7 ± 0.58). Year affected the numbers of COC that cleaved (P < 0.003) and the numbers of COC that developed to the blastocyst stage (P < 0.0001). Year also influenced the percentage of COC that cleaved (P < 0.0002) and the percentage of COC that developed to blastocysts (P < 0.0001). Group (AFC) did not influence (P > 0.19) the percentage of COC that cleaved (61.2 ± 2.83 v. 66.4 ± 2.83%, for low v. high AFC, respectively). Low AFC heifers had a lower (P < 0.002) percentage of COC that developed to blastocysts (10.3 ± 1.52%) than high AFC heifers (17.6 ± 1.52%). These results indicate that high AFC heifers, compared to low AFC heifers, have more COC recovered, more COC cleaved, and more COC developed to the blastocyst stage. The percentage of COC cleaved did not differ between AFC groups; however, the percentage of COC that developed to the blastocyst stage was greater for high than low AFC heifers. This suggests a potential advantage in maternal to embryonic transition for high compared with low AFC heifers.


2004 ◽  
Vol 16 (2) ◽  
pp. 259
Author(s):  
K. Kikuchi ◽  
M. Ozawa ◽  
D.-I. Fuchimoto ◽  
J. Noguchi ◽  
H. Kaneko ◽  
...  

A successful in vitro production (IVP) of porcine blastocysts, which enables piglet production after transfer to recipients, was reported (Kikuchi et al., 2002 Biol. Reprod. 66, 1033–1041). Generally, in the IVP system, both glucose and glutamine as energy sources were included in vitro culture (IVC) medium from Day 2 (Day 0=the day of in vitro fertilization) until Day 6. However, the exact requirement of these substances for the development to the blastocyst stage of IVP embryos has not yet been clarified. The objective of the present study was to evaluate whether these two substances are necessary for embryonic development to the blastocyst stage in culture during the period. Porcine cumulus-oocyte complexes were matured for 46h and fertilized in vitro as reported by Kikuchi et al. (see above). After removal of cumulus cells and spermatozoa, the oocytes were cultured subsequently in NCSU-37 supplemented with pyruvate and lactate (IVC-PyrLac) for 2 days. Then they were cultured until Day 6 in other IVC medium prepared as follows (1–6); Basic IVC medium (BM) was a modified NCSU-37 consisting of 108.7mM NaCl, 4.8mM KCl, 1.7mM CaCl2, 1.2mMKH2PO4, 1.2mM MgSO4, 25.1mM NaHCO3 and 4mgmL−1 fatty acid-free BSA. Then one or more of the following energy sources were supplemented to BM;; (1) 12mM sorbitol (SigmaUltra), 5.55mM glucose (Wako special grade) and 1.0mM glutamine (Sigma) (NCSU-37/Gln+), (2) 19.2mM sorbitol and 1.0mM glutamine (IVC-Sorbitol/Gln+); (3) 19.2mM mannitol (SigmaUltra) and 1.0mM glutamine (IVC-Mannitol/Gln+), (4) 12mM sorbitol and 5.55mM glucose (NCSU-37/Gln−); 5) 19.2mM sorbitol (IVC-Sorbitol/Gln−); and 6) 19.2mM mannitol (IVC-Mannitol/Gln−). The osmolarity of these media was adjusted to 283–285 osmolg−1. All embryos were fixed as whole mounts, stained and evaluated. The rate of blastocysts in NCSU-37/Gln+ (26.8%) was significantly higher (P&lt;0.05; by analysis of variance and Duncan’s multiple range test) than those in IVC-Sorbitol/Gln+, IVC-Mannitol/Gln+ and NCSU-37/Gln− (19.0%, 17.0% and 15.5%, respectively). A remarkable decrease in the rates in IVC-Sorbitol/Gln− and IVC-Mannitol/Gln− (P&lt;0.05; 1.4% and 2.0%, respectively) was observed. The cell numbers of NCSU-37/Gln+, IVC-Sorbitol/Gln+, IVC-Mannitol/Gln+ and NCSU-37/Gln− (55.5, 52.0, 49.6 and 58.7, respectively) had a tendency to be higher than those of IVC-Sorbitol/Gln− and IVC-Mannitol/Gln− (38.0 and 35.2, respectively). These results confirm that the supplementation of maturation medium with at least one energy source (glucose or glutamine) promotes embryonic development in vitro to the blastocyst stage, that the combination of both sources improves the chance of the embryonic survival, and that porcine embryos do not utilize sorbitol or mannitol as an energy source. The importance of glucose and glutamine is suggested for the development to the blastocyst stage of porcine IVP embryos.


Author(s):  
O. M. Sharan ◽  
V. Yu. Stefanyk ◽  
S. G. Shalovylo

New literature data on research aimed at improving the in vitro production of sheep embryos presents in the article. An analysis of the achievements of scientists from different countries to increase the efficiency of the main stages of embryo production in vitro: maturation of oocytes in vitro, their in vitro fertilization and in vitro embryo culture. In the literature experience has shown that the efficiency of oocyte maturation in vitro is significantly influenced by the experience and qualifications of scientists, the age of the egg donor, the improvement of the environment by adding roscovitin to inhibit meiosis, α-linolenic acid, cerium dioxide nanoparticles (CeO2 NPs) and sericin to accelerate nuclear maturation and increase the number of oocytes of the second meiotic metaphase (MII). The main factors influencing the effectiveness of in vitro fertilization have been identified, and the parameters of the limited time of fertilization ability of sperm and the ability of oocytes to fertilize, which is called the “fertile span”, have been determined. The main effective medium that increases the effectiveness of in vitro fertilization – synthetic oviduct fluid (SOF) with the addition of heparin and serum of cattle or sheep. The main parameters of sheep embryo culture in vitro are presented with the definition of the most commonly used media and their influence on embryonic development. Potential ways to improve the production of sheep embryos in vitro with the determination of morphological evaluation of categories of oocytes, methods of synchronization of their maturation in vitro are also highlighted. At the same time, literature data on the synchronization of oocyte-cumulus complexes with the use of a large number of inhibitors of meiotic division are presented, which according to many scientists may be a key factor in improving the efficiency of sheep embryo production in vitro. In addition, the results of studies of many scientists on the expansion of the fertile gap of oocytes of sheep cultured in vitro using certain biologically active substances were analyzed. In conclusion, the prospect of using the technology of in vitro production of sheep embryos in biomedical research is highlighted.


2011 ◽  
Vol 23 (1) ◽  
pp. 211
Author(s):  
K. R. Babu ◽  
R. Sharma ◽  
K. P. Singh ◽  
A. George ◽  
M. S. Chauhan ◽  
...  

Ovarian nitric oxide (NO) and that produced within the oocytes and embryos have been reported to play important roles in oocyte meiotic maturation and embryo development. Production of NO is catalyzed by NO synthase (NOS), which exists in 3 isoforms, the constitutive endothelial (eNOS) and neuronal (nNOS) isoforms and the inducible (iNOS) isoform. We have previously shown that low concentrations of NO stimulate and high concentrations inhibit embryo development, and that endogenous NO produced by iNOS is necessary for optimal embryo development in the buffalo. The present study was aimed at localizing different isoforms of NOS and examining their relative mRNA abundance in buffalo oocytes and embryos. Oocytes from slaughterhouse ovaries were subjected to in vitro maturation in 100-μL droplets (10 to 15 oocytes/droplet) of in vitro maturation medium (TCM-199 + 10% FBS + 5 μg mL–1 of pFSH + 1 μg mL–1 of oestradiol-17β + 0.81 mM sodium pyruvate + 10% buffalo follicular fluid + 50 μg mL–1 of gentamicin) for 24 h in a CO2 incubator (5% CO2 in air) at 38.5°C. In vitro fertilization was carried out by incubating in vitro-matured oocytes with 2 to 4 million spermatozoa mL–1 for 18 h. The presumed zygotes were cultured on original beds of cumulus cells in in vitro culture medium (mCR2aa + 0.6% BSA + 10% FBS) for up to 8 days post-insemination. Immature and in vitro-matured oocytes and embryos at the 2-cell, 4-cell, 8- to 16-cell, morula, and blastocyst stages were examined for the presence of NOS isoforms by indirect immunofluorescence staining using epifluorescence microscopy and RT-PCR. Each experiment was repeated in triplicate, and data were analysed using one-way ANOVA, after arcsine transformation of percentage values. Expression of all 3 NOS isoforms was detected inside the cytoplasm, in all the stages of oocytes and embryos examined, by both immunofluorescence and RT-PCR. Abundance of the iNOS transcript was significantly higher (P ≤ 0.01) in the morula and blastocyst stages compared with that in immature and in vitro-matured oocytes and in embryos at the 2-cell, 4-cell, and 8- to 16-cell stages, indicating that its expression was up-regulated at the 8- to 16-cell stage. The expression of eNOS was significantly higher (P ≤ 0.05) in the immature and mature oocytes and in 8- to 16-cell stage embryos, morulae, and blastocysts than in the early-cleavage embryos at the 2- and 4-cell stages, indicating that it was down-regulated after fertilization and was up-regulated again at the 8- to 16-cell stage. Abundance of the nNOS transcript was not significantly different among all the stages of oocytes and embryos examined. These results demonstrate that different NOS isoforms are expressed in a dynamic manner during embryonic development in the buffalo. The role of an increase in expression of iNOS and eNOS at the 8- to 16-cell stage, at which a developmental block occurs in this species, needs to be examined.


2011 ◽  
Vol 23 (1) ◽  
pp. 209
Author(s):  
S. Miyashita ◽  
K. Miyata ◽  
C. Tachibana ◽  
Y. Inaba ◽  
H. Koyama ◽  
...  

The objective of this study was to investigate the effect of stage of corpus luteum (CL) development on the in vitro production of bovine embryos. Ovaries were classified according to the expected day of the oestrous cycle based on the morphology of the ovaries. Ovaries with a corpus hemorrhagicum and the remnant of the follicular lumen filled with blood were considered the early luteal stage (Days 2 to 4; Day 0 = day of ovulation, n = 46). Ovaries with a large mass of orange tissue in the CL were classified as the midluteal stage (Days 7 to 10, n = 42). Cumulus–oocyte complexes (COC) were collected by aspiration of 2- to 6-mm follicles. The COC were classified into the following grades: COC with >3 compact layers of cumulus cells and evenly granulated cytoplasm were classified into Grade 1; COC with >3 layers cumulus cells and evenly granulated cytoplasm were classified into Grade 2; COC with partially remaining cumulus cells and abnormal cytoplasm were classified into Grade 3; COC without cumulus cells or those with expanded cumulus cells were classified into Grades 4 and 5, respectively. Grades 1 and 2 COC were in vitro matured for 20 h in TCM-199 supplemented with 5% calf serum and 0.02 mg mL–1 of FSH at 38.5°C under an atmosphere of 5% CO2 in air. Matured COC were inseminated with 5 × 106 sperm for 18 h. Presumptive zygotes were cultured in CR1aa medium supplemented with 5% calf serum at 38.5°C under an atmosphere of 5% O2, 5% CO2, and 90% N2 for 9 days (fertilization = Day 0). The mean number of COC and the proportion of COC classified as Grades 1 and 2 were analysed by ANOVA. Cleavage rates on Day 3 and blastocyst rates on Days 7 to 9 were analysed by a chi-square test. The mean number of recovered oocytes in the early luteal stage (18.7 ± 9.5) was significantly higher (P < 0.05) than the number in the midluteal stage (12.2 ± 5.7). The proportion of Grades 1 and 2 oocytes in the early luteal stage [66.7% (531/789)] was significantly higher (P < 0.01) than that in the midluteal stage [51.6% (252/484)]. The cleavage and blastocyst rates in the early luteal stage [60.9% (181/297) and 32.7% (97/297), respectively] were significantly higher (P < 0.05) than those in the midluteal stage [50.7% (76/150) and 20.7% (31/150) respectively].The present study suggests that the stage of development of the CL in bovine ovaries influences the number of recovered oocytes per ovary and the development of in vitro production of bovine embryos.


2010 ◽  
Vol 22 (1) ◽  
pp. 285
Author(s):  
S. Wohlres-Viana ◽  
M. M. Pereira ◽  
A. P. Oliveira ◽  
J. H. M. Viana ◽  
M. A. Machado ◽  
...  

The Zebu breeds (Bos indicus) are different from European breeds (Bos taurus) in some aspects of their reproductive physiology, including follicle recruitment, number of follicular waves, and oocyte ultrastructure. On the other hand, embryos produced in vivo and in vitro show morphological and developmental differences, which can be related to culture environment. The aim of this study was to evaluate the effect of breed (Gyr v. Holstein) within embryo production system (in vivo and in vitro), as well as effect of production systems within breeds on relative abundance of transcripts related to formation, survival, and subsequent development of blastocysts, such as those involved in water and small solutes transport (Aquaporins 3 and 11), blastocoel formation (Na+/K+-ATPase a1 and |52), and cellular stress response (Peroxiredoxin 1). For in vivo embryo production, donors were superstimulated with FSH and inseminated, and embryos were recovered 7 days after AI. For in vitro embryo production, oocytes recovered by ovum pickup were in vitro matured and fertilized and then cultured for 7 days in culture medium under 5% CO2 at 38.5°C. For each group, blastocysts (n = 15) distributed in 3 pools were used for RNA extraction (RNeasy MicroKit, Qiagen, Valencia, CA, USA), followed by RNA amplification (Messageamp II amplification kit, Ambion-Applied Biosystems, Foster City, CA, USA) and reverse transcription (SuperScript III First-Stand Synthesis Supermix, Invitrogen, Carlsbad, CA, USA). The cDNA were submitted to real-time PCR, using the H2a gene as endogenous control, and analyzed by REST© software. To evaluate breed effect within the production systems, 2 comparisons were performed: (1) in vivo: Gyr v. Holstein and (2) in vitro: Gyr v. Holstein, considering Holstein data as 1.00. To evaluate production system effect within breeds, 2 comparisons were performed: (1) Gyr: in vivo v. in vitro and (2) Holstein: in vivo v. in vitro, considering in vivo produced embryo data as 1.00. The results are shown as mean ± SEM. For in vivo comparison between breeds, Aquaporin 3 (1.66 ± 0.77), Na+/K+-ATPase a1 (1.61 ± 0.56), and Peroxiredoxin 1 (1.61 ± 0.66) were up-regulated (P < 0.05) in Gyr embryos when compared with Holstein embryos, whereas for in vitro comparison, no differences (P > 0.05) were found. For comparisons between production systems within breeds, only Peroxiredoxin 1 (0.31 ± 0.39) was down-regulated (P < 0.01) in in vitro produced Gyr embryos when compared with in vivo counterparts. No differences (P > 0.05) were found between production systems for the Holstein breed. In conclusion, these data suggest that there is a difference on gene expression between Bos taurus and Bos indicus blastocysts, but such difference between breeds can be attenuated by the in vitro production system, indicating an embryo adaptation to the in vitro culture conditions. The data also suggest that the in vitro production system can influence the amount of transcripts in Gyr embryos. Other genes should be evaluated for a better understanding of these differences. Financial support was provided by CNPq and FAPEMIG.


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