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Öğe Determination of the relationship between serum anti-Mullerian hormone level and superovulatory response in Simmental cows(Wliey, 2019) Sevgi, Ramazan; Erdem, Hüseyin; Karaşahin, Tahir; Yılmaz, Mehmet Ali; Satılmış, Muharrem; Okuroğlu, Alaeddin; Ünal, İlker; Dursun, Şükrü; Alkan, Hasan; Satılmış, FatmaThe most significant focal points of the embryo transfer technology are as follows: the selection of donors, the response of the selected donor to the superovulation protocol and the obtained number of the transferable embryos. For this purpose, it is suggested that donor selection can be done by anti-Mullerian hormone (AMH) levels, and embryo production is evaluated. AMH is secreted by the granulosa cells of primordial, pre-antral and antral follicles below 4 mm in the ovary, independent of FSH. Therefore, the aim of this study was to investigate the relationship between serum AMH levels and the number of corpus luteum (CL), total embryos and transferable embryos that were shaped after a uniform superovulation protocol. For this reason, 48 Simmental cows, which were located at General Directory of Agricultural Enterprises (region, province, etc. instead of the general directorate), were used as donors for the embryo transfer. Blood samples were taken at random, regardless of the stage of animal's sexual cycle. AMH levels were measured by enzyme-linked fluorescent assay (ELFA) method of the miniVIDAS (R) (bioMerieux SA) using AMH Bovine Test Kit. According to the statistical analyses of the obtained data, AMH levels were positively correlated with CL and total embryos (p .05). No significant correlations between AMH and transferable embryos were approved (p > .05). It was also determined that each 200 pg/ml increase in serum AMH level resulted in one increase in CL number. Overall, considering the positive correlation between AMH level and the obtained number of CL and total embryos after a superovulation treatment, it was concluded that measuring blood AMH level prior to any further costly implementation may be an effective method in donor selection.Öğe Effect of embryo quality and developmental stages on pregnancy rate during fresh embryo transfer in beef heifers(Springer, 2020) Erdem, Hüseyin; Karaşahin, Tahir; Alkan, Hasan; Dursun, Şükrü; Satılmış, Fatma; Güler, MehmetThe objective of this study was to evaluate the effect of embryo quality and developmental stages on pregnancy rate in beef heifer recipients. The present study used 168 Simmental breed cows as donors, and 618 beef cattle breed heifers as recipients. The quality and developmental stages of the collected embryos were evaluated according to the criteria specified by the International Embryo Technology Society. Accordingly, the embryos in the compact morula, early blastocyst, blastocyst, and expanded blastocyst stages that were of Code I (excellent) and Code II (good) quality levels were transferred as fresh embryos to the recipient heifers. Prior to the transfer, the recipients were synchronized using the Ovsynch protocol, and the embryos obtained were transferred to 618 beef heifers. Pregnancy examinations were performed on days 30 and 60. On day 30, the pregnancy rates with Code I and Code II embryos were determined as 44.15% and 32.58%, respectively. According to the developmental stages, the pregnancy rates with Code I quality compact morula, early blastocyst, blastocyst, and expanded blastocyst were determined as 44.64%, 45.67%, 45.83%, and 33.33%, respectively. The rates of pregnancy with Code II quality compact morula, early blastocyst, and blastocyst were determined as 32.03%, 32.14%, and 50.0%, respectively. In conclusion, the pregnancy rates with Code I quality embryos were found to be higher compared with Code II embryos (P < 0.05). It was also determined that the embryonic developmental stages had no effect on the pregnancy rate (P > 0.05).Öğe Effect of flunixin meglumine treatment during and after embryo transfer on the pregnancy rate in cattle(John Wiley and Sons Inc, 2021) Karaşahin, Tahir; Alkan, Hasan; Satılmış, Fatma; Dursun, Şükrü; Erdem, HüseyinThis study aimed to determine the effect of flunixin meglumine treatment during and after the transfer of in vivo produced embryos to Angus (cows) and Holstein (cows and heifers) breeds of cattle on pregnancy rate. Holstein cows were used as donors in the study. A double dose of prostaglandin F2? was administered to the recipient animals for synchronization. Uterine flushing was performed in donors on day 7 after artificial insemination. A total of 295 transferable embryos were obtained. These embryos were transferred to Angus cows (n = 85), Holstein heifers (n = 80) and Holstein cows (n = 130). After the transfer, these animals were divided into three subgroups. The first subgroup (TI) was administered flunixin meglumine during embryo transfer, and the second subgroup (TII) was administered flunixin meglumine both during embryo transfer and on days 8 and 9 after the transfer. The third subgroup (TIII) was not administered anything and it was considered the control group. Pregnancy examination of the recipients was performed on days 30–35 after the transfer using real-time ultrasonography. The pregnancy rates after embryo transfer were found to be 43.52% in Angus cows, 42.5% in Holstein heifers, and 24.61% in Holstein cows (p <.05). When the animals were not classified according to breed, the pregnancy rates in subgroups TI, TII and TIII were found to be 29.29%, 45.10% and 29.79%, respectively (p <.05). In addition, the pregnancy rates were higher in TII and TIII subgroups of Angus cows and Holstein heifers compared to that of Holstein cows (p <.05). As a result, the pregnancy rates obtained after embryo transfer in Angus cows and Holstein heifers were found to be higher than that in Holstein cows. In addition, it was concluded that the administration of flunixin meglumine during and during/after embryo transfer has a positive effect on pregnancy rates in Angus cows and Holstein heifers.Öğe Evaluation of the factors that affect the pregnancy rates during embryo transfer in beef heifers(Blackwell Publishing Ltd, 2020) Alkan, Hasan; Karaşahin, Tahir; Dursun, Şükrü; Erdem, Hüseyin; Satılmış, Fatma; Güler, MehmetThe aim of this study was to evaluate the effects of the transfer side, transfer location, cervix transfer score, type and diameter of corpus luteum (CL) during embryo transfer on pregnancy rates in beef heifers. Progesterone-based synchronization and superovulation protocol were applied to Simmental cows used as donors (n = 168). Uterine flushings were performed on day 7 following artificial insemination. Obtained Code I (excellent or good) and II (fair) quality embryos were transferred to recipient beef heifers (n = 561). During embryo transfer, side of transfer (right or left), transfer location (the cranial or middle third of uterine horn), cervix transfer score (easy, moderate or difficult) and type (CLa, CLb and CLc) and diameter of CL were determined. Pregnancy rates following the transfer of Code I and II embryos were 44.66% and 33.07%, respectively (p <.05). The rates of pregnancy after transfers to the right and left uterine horn were 37% and 42.2%, respectively (p >.05). The pregnancy rates were 41.2%, 34.9% and 30.3% for cervix transfer scores as easy, moderate and difficult, respectively (p >.05). Pregnancy rates after transfer to the cranial third and middle third were 41.06% and 29.67%, respectively (p <.05). According to types of CL, pregnancy rates were 31.7%, 40.4% and 45.3% for CLa, CLb and CLc, respectively (p <.05). Moreover, it was found that as the CL diameter increased, the pregnancy rates increased. As a result, it was concluded that there was no effect of side of transfer and cervix transfer score, but embryo quality, transfer location, type and diameter of CL had significant effects on the pregnancy rate during embryo transfer in beef heifers.Öğe Evaluation of the relationship between serum paraoxonase-1 activity and superovulation response/embryo yield in holstein cows(Japanese Society of Veterinary Science, 2021) Alkan, Hasan; Satılmış, Fatma; Karaşahin, Tahir; Dursun, Şükrü; Erdem, HüseyinIn this study, the effect of serum paraoxonase-1 (PON-1) activity on superovulation response and embryo yield was evaluated. The study material comprised 50 Holstein cows aged 3–4 years on postpartum day 90–120 with a body condition score of 3–3.25. A progesterone-based estrus synchronization protocol was initially administered to the selected donors. For this purpose, progesterone source was inserted intravaginally (day 0) and gonadotropin-releasing hormone injection was performed (day 6). Seven days after the insertion of progesterone device, follicle-stimulating hormone injections (total dose of 500 µg in decreasing doses for 4 days) were administered for superovulation. On the morning of the ninth day, prostaglandin (PG) F2? was administered, and the progesterone device was removed from the vagina in the evening on the same day. Two days after PGF2? administration, fixed-time artificial insemination was performed in the morning and in the evening. On the day of artificial insemination, blood samples were taken from the donors to determine the serum PON-1 activity. Uterine flushing was performed seven days after insemination. The results revealed that the serum PON-1 activity (mean ± SD, 562.71 ± 140.23 U/l) of the cows that responded to superovulation (donors with total corpus luteum count of ?3 in both ovaries) was higher than those (389.91 ± 80.51 U/l) that did not (P<0.05). On the day of insemination, a positive correlation was determined between serum PON-1 activity and the counts of total corpus luteum (r=0.398), total oocyte/embryo (r=0.468), transferable embryo (r=0.453), and Code I embryos (r=0.315, P<0.05). Unlike the Code I embryos, there was no significant correlation between serum PON-1 activity and the number of Code III embryos. Moreover, no significant difference in the number of Code III embryos between the two PON-1 groups was observed. However, embryo yield and quality were found to have increased with increased PON-1 activity. Therefore, it was concluded that serum PON-1 activity may be associated with superovulation response, embryo yield and quality in donor cows.Öğe Relationship between total antioxidant/oxidant status, and oxidative stress index and superovulation response in donor cows(Elsevier, 2021) Karaşahin, Tahir; Alkan, Hasan; Satılmış, Fatma; Dursun, Şükrü; Öztürk, Caner; Bulut, Gaye; Aksoy, Neşe Hayat; Tekindal, Mustafa Agah; Çağlayan, Tamer; Yeşilkaya, Ömer Faruk; Erdem, HüseyinThe aim of the present study was to determine the effects of serum total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) on counts of corpus luteum, transferable embryo, and embryo quality in cows treated with superovulation protocol. A total of 60 Simmental cows (postpartum 90 to 120 days) were used. The donors were treated with a 9 day-progesterone based estrus synchronization protocol. On the 7th day of the progesterone treatment, donors were treated with FSH twice daily as decreasing doses for 4 days. On day 9, PGF 2 injection was performed in the morning and progesterone source was removed in the evening. The cows were inseminated twice artificially on day 11 at 12 hours interval. On the day of artificial insemination, blood samples were collected to determine serum TAS, TOS and OSI concentrations. Uterine flushing was performed on day 7 after artificial insemination. Serum TAS, TOS and OSI concentrations of cows were 1.62 mu mol/L, 5.44 mu mol/L and 0.45 AU, respectively. There was a positive correlation between TAS concentration and the counts of transferable embryo, Code I and II quality embryo (P<0.05). TOS and OSI concentrations were negatively correlated with the counts of transferable embryo and Code I embryo, and positively correlated with unfertilized oocyte counts (P<0.05). As a result, it was concluded that TAS, TOS, and OSI affected the counts of transferable embryo, embryo quality, and unfertilized oocyte in donor cows.Öğe Retrospective evaluation of factors affecting superovulatory response in embryo production in Simmental cattle(TUBITAK, 2020) Erdem, Hüseyin; Alkan, Hasan; Karasahin, Tahir; Dursun, Şükrü; Satılmış, Fatma; Güler, MehmetIn the present study, it was aimed to investigate the effect of lactation status, days in milk (DIM), follicle stimulating hormone (FSH) dose, and repeated superstimulations on superovulation response and embryo yield in Simmental cattle. In the present study, 193 Simmental breed cattle (lactating, nonlactating, and heifer) were used as donors, of which 149 were superovulated only once and the other 44 were superovulated for 3 times. Progesterone-based estrus synchronization protocol was applied to the donors. Starting from day 7, FSH was given intramuscularly to donors in decreasing doses twice a day for 4 days. The donors were injected with prostaglandin F2? at the 5th FSH treatment and progesterone source was removed 12 h later. Artificial insemination was performed twice after the removal of progesterone source. In the present study, 134 of the 149 donors who underwent a superovulation protocol for the first time responded to superovulation treatment (?3 corpus luteum (CL); 89.93%) and the mean count of transferable embryos per donor was 5.58. No statistical difference was observed for the counts of CL, total oocyte/embryo, and transferable embryo among heifers, lactating cows, and nonlactating cows. A positive correlation was noted between DIM and embryo yield (P < 0.05). Superovulation response and embryo yield were increased depending on the dose of FSH in cows undergoing superstimulation treatment (P < 0.05). Although no statistical difference was detected between the embryo yields obtained from the first two applications in repeated superovulation treatments, the embryo yield decreased after the 3rd superstimulation. In conclusion, in Simmental breed cows, the embryo yield in superovulation applications was unaffected by lactation status, but was affected by the applied FSH dose and DIM. It was also concluded that the embryo yield decreased after the 3rd application in repeated superovulation treatments.
