Browsing by Author "Alkan, Ali"
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Item Conception rate after timed artificial insemination protocols using by PGF(2 alpha) and GnRH in dairy heifers(Wiley, 2010-09) Alkan, Ali; Güzeloğlu, Aydın; Okut, Hayrettin; Gümen, Ahmet; Keskin, Abdülkadir; Yılmazbaş, Gülnaz Mecitoğlu; Karakaya, Emre; Uludağ Üniversitesi/Veterinerlik Fakültesi/Klinik Bilimler Bölümü.; 0000-0003-2817-3221; AAH-1406-2021; AAG-4440-2019; AAH-3831-2021Item Conception rate in lactating dairy cows after artificial insemination with sexed semen(Wiley, 2011-08) Karakaya, Ebru; Keskin, Abdulkadir; Mecitoğlu, Gülnaz Yılmazbaş; Alkan, Ali; Doğan, Ramazan; Gümen, Ahmet; Uludağ Üniversitesi/Veterinerlik Fakültesi/Veterinerlik Doğum ve Jinekolojisi Bölümü.; 0000-0003-2817-3221; AAH-1555-2021; AAH-3831-2021; AAG-4440-2019; AAH-1406-2021Item The effect of intrauterine cephapirin treatment after insemination on conception rate in repeat breeder dairy cows subjected to the progesterone-based Ovsynch protocol(TÜBİTAK, 2012) Alkan, Ali; Taşdemir, Umut; Okut, Hayrettin; Gümen, Ahmet; Mecitoğlu, Gülnaz Yılmazbaş; Keskin, Abdulkadir; Karakaya, Ebru; Uludağ Üniversitesi/Veteriner Fakültesi/Jinekoloji ve Doğum Anabilim Dalı.; 0000-0003-2817-3221; AAG-4440-2019; AAH-1406-2021; AAH-3831-2021; 6602393069; 36457964000; 24473229800; 36457784500Subclinical endometritis contributes to repeat breeder syndrome in dairy cows. This study evaluated the effect of intrauterine cephapirin benzathine administration aft er timed artificial insemination (TAI) on the conception rate (CR) in repeat breeder dairy cows. To determine the antibiotic effects, all cows (n = 335) that had more than 3 services with no clinical abnormalities of the reproductive tract received the same combined synchronisation protocol: an ear implant containing progestagen using the Ovsynch protocol and a third gonadotropin-releasing hormone (GnRH) administration 7 days aft er TAI. Cows in the treatment group (TRT; n = 160) received intrauterine cephapirin 12 h aft er TAI, and cows in the control group (CON; n = 175) did not receive intrauterine antibiotics. The percentage of cows that responded to the first (67.5% in TRT, 70.9% in CON) and second (98.8% in TRT, 97.1% in CON) GnRH of Ovsynch was similar between the groups. In addition, the response to the third GnRH administration aft er TAI (88.1% in TRT, 83.9% in CON) did not differ between the groups. However, there was no effect of the cephapirin administration on CR on days 31 and 62 in the repeat breeder cows (43.8% in TRT and 44.0% in CON; 39.4% in TRT and 40.6% in CON, respectively). Thus, post-TAI intrauterine cephapirin administration was not found to be useful for the treatment of potential subclinical endometritis in repeat breeder dairy cows.Item Effect of presynchronization strategy before ovsynch on fertility at first service in lactating dairy cows(Elsevier Science, 2012-11) Alkan, Ali; Okut, Hayrettin; Wiltbank, Milo Charles; Gümen, Ahmet; Keskin, Abdülkadir; Yılmazbaş, Gülnaz Mecitoğlu; Karakaya, Ebru; Uludağ Üniversitesi/Veteriner Fakültesi/Jinekoloji ve Doğum Anabilim Dalı.; 0000-0003-2817-3221; AAH-1406-2021; AAG-4440-2019; AAH-3831-2021; 6602393069; 24473229800; 36457964000; 36457784500The aim of this study was to evaluate the effect of presynchronization with or without the detection of estrus on first service pregnancy per artificial insemination (P/AI) and on Ovsynch outcome in lactating dairy cows. A total of 511 cows were divided randomly but unevenly into 3 treatment groups at 44 to 50 days in milk (DIM). Ovsynch was started at the same time (69 to 75 DIM) in all three groups. Cows in the Ovsynch group (CON, N = 126) received no presynchronization before Ovsynch, and all cows were bred by timed AT (TAI). Cows in the presynchronization with estrus detection (PED) and the presynchronization with only TAI (PTAI) groups received two doses of prostaglandin F-2 alpha (PGF) 14 days apart, starting at 44 to 50 DIM. Ovsynch was initiated 11 days after the second PGF treatment. Cows in the PED group (N = 267) received AI if estrus was detected after either PGF injection. Cows that were not determined to be in estrus after PGF injection received Ovsynch and TAI. Cows in the PTAI group (N = 118) were not inseminated to estrus, with all cows receiving TAI after Ovsynch. The ovulatory response to the first GnRH injection administered as part of Ovsynch differed (P = 0.002) among treatment groups (83.1% in PTAI, 72.6% in PED, and 62.7% in CON). However, the ovulatory response to the second injection of GnRH during Ovsynch did not differ among treatment groups. Of the 267 PED cows, a total of 132 (49.4%) exhibited estrus and were inseminated. The P/AI at the 31-day pregnancy diagnosis was similar between the cows in the PED group with AI after estrus detection (37.9%; 50/132) and those bred with TAI (34.1%; 46/135). The P/AI in the CON group (46.8%; 59/126) was greater (P < 0.05) than that in the PED group (36.0%; 96/267). In addition, the P/AI in the CON group was greater (P = 0.04) than that in the PED cows receiving TAI (34.1%; 46/135) but less than that in the PED cows bred to estrus (37.9%; 50/132) (P = 0.16). At the 31-day pregnancy diagnosis, the cows in the PTAI group had greater P/AI (55.9%; 66/118) than both those in the PED group (P < 0.01; either estrus or TAI) and those in the CON group (P = 0.08). Thus, presynchronization with PGF (PTAI) increased the ovulatory response to Ovsynch and improved P/AI in dairy cows. Interestingly, the breeding of cows to estrus during presynchronization reduced fertility to the TAI and overall fertility, including cows bred to estrus and TAI. These results indicate that maximal fertility is obtained when all cows receive TAI after the presynchronization protocol.Item Effects of presynchronization with gonadotropin-releasing hormone-prostaglandin F-2 alpha or progesterone before Ovsynch in noncyclic dairy cows(Elsevier Science, 2012-12) Alkan, Ali; Okut, Hayrettin; Yılmazbaş, Gülnaz Mecitoğlu; Karakaya, Ebru; Keskin, Abdülkadir; Gümen, Ahmet; Uludağ Üniversitesi/Veteriner Fakültesi/Jinekoloji ve Doğum Anabilim Dalı.; 0000-0003-2817-3221; AAH-3831-2021; AAG-4440-2019; AAH-1406-2021; 36457964000; 36457784500; 24473229800; 6602393069The aim of this study was to evaluate the efficiency of presynchronization with GnRH and PGF(2 alpha) or with progesterone on overall Ovsynch (OVS) outcomes in noncyclic dairy cows. Cows were scanned 7 d apart with ultrasonography to determine cyclicity. Noncyclic cows (n = 281; no corpus luteum on ovaries at both examinations) were randomly divided into 3 groups. In the GP group (n = 108), the cows received GnRH and PGF(2 alpha) (PGF) administrations 7 d apart, and OVS was started 11 d after PGF (GnRH-7 d-PGF-11 d-OVS). In the P4 group (n = 90), the cows were treated for 7 d with an intravaginal progesterone (P4) implant (PRID), and then OVS was started 11 d after removal of the implant (7 d PRID-11 d-OVS). The control group (CON, n = 83) did not receive any presynchronization, and OVS was started at the same time as in the other groups (18 d-OVS). The percentage of cows that became cyclic at the beginning of OVS was lower in the CON group (38.6%; 32/83) than in the presynchronization groups (66.7%, 72/108 in GP; 71.1%, 64/90 in P4). The response to the first GnRH of OVS did not differ among groups (63.9%, 53/83 in CON; 67.6%, 73/108 in GP; 63.3%; 57/90 in P4), and synchronization rates were similar among the groups (74-82%). The cows that responded to presynchronization treatments (GP or P4) had higher pregnancy per artificial insemination (P/AI) than did nonresponding cows. Pregnancy per AI at 31 d did not differ between groups (30.1%, 25/83 in CON; 43.5%, 47/108 in GP; and 35.6%, 32/90 in P4). However, CON cows (24.1%, 20/83) had lower P/AI at 62 d than GP cows (41.7%, 45/108). Embryonic loss was higher in CON (20%, 5/25) compared with the P4 group (3%, 1/32). The administration of GnRH followed by PGF or exogenous progesterone (PRID) similarly increased the percentage of cows that became cyclic before Ovsynch in noncyclic cows, but fertility did not improve. However, the cows that responded to presynchronization had higher fertility rates than the nonresponding cows.Publication Efficacy and safety of trastuzumab emtansine in her2 positive metastatic breast cancer: Real-world experience(Taylor & Francis, 2021-06-05) Bahçeci, Aykut; Paydaş, Semra; Ak, Naziye; Ferhatoğlu, Ferhat; Saip, Pınar Mualla; Şeydaoğlu, Gülşah; Bilici, Mehmet; Şimşek, Melih; Tekin, Salim Başol; Çalıkuşu, Züleyha; Yavuz, Sinan; Şahin, Ahmet Bilgehan; Çubukcu, Erdem; Evrensel, Türkkan; Değirmencioğlu, Serkan; Demiray, Atike Gökçen; Yumuk, Perran Fulden; Alan, Özkan; Çıkman, Duygu İlke; Demirelli, Fuat Hulusi; Köstek, Osman; Gökyer, Ali; Doğan, Mutlu; Bal, Öznur; Çakar, Burcu; Gökmen, Erhan; Yamaç, Deniz; Korkmaz, Taner; Aliyev, Altay; Keskin, Özge; Urvay, Semiha; Buyukşimşek, Mahmut; Karadeniz, Cemile; Yıldız, Birol; Çınkır, Havva Yeşil; Demir, Hacer; Beypınar, İsmail; Karacin, Cengiz; Eser, Kadir; Baykara, Meltem; Kılıçkap, Saadettin; Okutur, Kerem; Bulut, Gülcan; Alkan, Ali; Arpacı, Erkan; Pilancı, Kezban Nur; Demir, Atakan; Işık, Deniz; Yıldırım, Nilgün; ŞAHİN, AHMET BİLGEHAN; ÇUBUKÇU, ERDEM; EVRENSEL, TÜRKKAN; 0000-0002-7846-0870 ; AAM-4927-2020; JGT-4101-2023 ; EXZ-0745-2022Aim The aim of this study is to evaluate the efficacy and toxicity of trastuzumab emtansine (T-DM1) in cases with metastatic breast cancer (mBC) in different lines of treatment. Method Retrospective analysis of T-DM1 results of human epidermal growth factor receptor 2 (Her2) positive 414 cases with mBC from 31 centers in Turkey. Findings Except 2, all of the cases were female with a median age of 47. T-DM1 had been used as second-line therapy in 37.7% of the cases and the median number of T-DM1 cycles was 9. Progression-free survival (PFS) and overall survival (OS) times were different according to the line of treatment. The median OS was found as 43, 41, 46, 23 and 17 months for 1st, 2nd, 3rd, 4th and 5th line, respectively (p = 0.032) while the median PFS was found as 37, 12, 8, 8 and 8 months, respectively (p = 0.0001). Treatment was well tolerated by the patients. The most common grade 3-4 adverse effects were thrombocytopenia (2.7%) and increased serum gamma-glutamyl transferase (2%). Discussion The best of our knowledge this is the largest real-life experience about the safety and efficacy of T-DM1 use in cases with mBC after progression of Her2 targeted treatment. This study suggests and supports that T-DM1 is more effective in earlier lines of treatment and is a reliable option for mBC.Item Fertility in dairy cows after artificial insemination using sex-sorted sperm or conventional semen(Wiley, 2014-04) Alkan, Ali; Taşdemir, Umut; Santos, José Eduardo P.; Karakaya, Ebru Bilen; Yılmazbaş, Gülnaz Mecitoğlu; Kesin, Abdülkadir; Gümen, Ahmet; Uludağ Üniversitesi/Veterinerlik Fakültesi/Klinik Bilimler Bölümü.; 0000-0003-2817-3221; AAH-1406-2021; AGY-3496-2022; AAH-3831-2021; AAG-4440-2019; 36457784500; 36457964000; 24473229800; 6602393069Contents The aim of this study was to compare pregnancy per artificial insemination (P/AI) after timed AI with sex-sorted sperm (SS) or conventional semen (CS) in lactating dairy cows. Cyclic cows (n=302) were synchronized by Ovsynch and randomly assigned into two groups at the time of AI. Cows with a follicle size between 12 and 18mm and clear vaginal discharge at the time of AI were inseminated with either frozen-thawed SS (n=148) or CS (n=154) of the same bull. A shallow uterine insemination was performed into the uterine horn ipsilateral to the side of probable impending ovulation. Pregnancy per AI on Day 31 tended (p=0.09) to be less for SS (31.8%) than CS (40.9%). Similarly, P/AI on Day 62 was less (p=0.01) for cows inseminated with SS (25.7%) compared with CS (39.0%). The increased difference in fertility between treatments from Days 31 to 62 was caused by the greater (p=0.02) pregnancy loss for cows receiving SS (19.2%) than CS (4.8%). Cow parity (p=0.02) and season (p<0.01) when AI was performed were additional factors affecting fertility. Primiparous cows had greater P/AI than multiparous cows both on Day 31 (41.7% vs 25.0% in SS and 53.0% vs 31.8% in CS groups) and on Day 62 (33.3% vs 20.5% in SS and 48.5% vs 31.8% in CS groups). During the hot season of the year, P/AI on Day 31 was reduced (p=0.01) in the SS group (19.6%) when compared with the rates during the cool season (38.1%). In conclusion, sex-sorted sperm produced lower fertility results compared to conventional semen even after using some selection criteria to select most fertile cows.Item Fertility of lactating dairy cows treated with different timed artificial insemination protocols before using of sex-sorted sperm vs. conventional semen(Wiley, 2014) Bisinotto, Rafael; Santos, José Eduardo P.; Gümen, Ahmet; Bilen, Ebru; Yılmazbaş, Gülnaz Mecitoğlu; Keskin, Abdulkadir; Alkan, Ali; Uludağ Üniversitesi.; 0000-0003-4837-1858; 0000-0003-2817-3221; AIF-3815-2022; AAH-3831-2021; AAG-4440-2019; AAH-1406-2021Item Improving conception rate in lactating dairy cows by using modified ovsynch protocol during summer(Uludağ Üniversitesi, 2012-01-24) Tasdemir, Umut; Alkan, Ali; Okut, Hayrettin; Mecitoglu, Gulnaz Yılmazbas; Gumen, Ahmet; Keskın, Abdulkadir; Karakaya, Ebru; Uludağ Üniversitesi/Veteriner Fakültesi.The aim of this study was to test two different timed artificial insemination (AI) protocols in order to improve the percentage of pregnant cows per AI in lactating dairy cows during the summer. Cows (n=140) were randomly divided into two groups; cows in the OVS group (n=75) received the Ovsynch protocol (GnRH–7d–PGF2α–2d–GnRH–16h–AI), and cows in the MOVS group (n=65) received the Ovsynch protocol with exogenous progesterone (P4) which administrated between GnRH and PGF2α. In addition, GnRH was injected 7 d after AI in the MOVS group (GnRH–P4–7d –PGF2α–2d–GnRH–16h–AI–7d–GnRH). Response to the second GnRH treatment of Ovsynch (GnRH-2) was greater (P<0.03) in the MOVS (98.5%) than the OVS (89.3%) group. Although P/AI at 31 d was numerically greater in the MOVS (46.2%, 30/65) than the OVS (37.3%, 28/75) group, this difference was statistically insignificant. Thus, because of the greater response to GnRH-2 and P/AI in MOVS compared with the OVS group, the MOVS protocol can be used to improve P/AI in lactating dairy cows during the summer, but further studies are needed to be evaluated the effects of the MOVS protocol on P/AI during the summer.Item Reducing the duration between gonadotropin-releasing hormone (GnRH) and prostaglandin F-2 alpha treatment in the Ovsynch protocol to 6 days improved ovulation to second GnRH treatment, but inclined to reduce fertility(Elsevier, 2013-06) Alkan, Ali; Mecitoğlu, Gülnaz Yılmazbaş; Karakaya, Ebru Bilen; Keskin, Abdülkadir; Gümen, Ahmet; Uludağ Üniversitesi/Veterinerlik Fakültesi/Veteriner Doğum ve Jinekoloji Bölümü.; 0000-0003-2817-3221; AAG-4440-2019; AAH-3831-2021; AGY-3496-2022; AAH-1406-2021; 36457964000; 36457784500; 24473229800; 6602393069The aim of this study was to test Ovsynch (OVS) versus modified OVS (decreasing the interval between first GnRH and PGF(2 alpha) to 6 d) protocols on pregnancy per artificial insemination (AI) and OVS outcomes in cyclic dairy cows. Cyclic cows (n = 920) were assigned to 1 of 2 groups: the OVS7 group (n = 459) received the OVS protocol [GnRH treatment, PGF(2 alpha) treatment 7 d later, a second GnRH (GnRH2) treatment 56 h later, and timed AI (TAI) 16 to 18 h after the GnRH2 treatment], and the OVS6 group (n = 461) received a modified OVS protocol, in which the interval between the first GnRH and PGF(2 alpha) was decreased to 6 d (GnRH treatment, PGF(2 alpha) treatment 6 d later, GnRH2 treatment 56 h later, and TAI 16 to 18 h after the GnRH2 treatment). The response to the first GnRH of OVS was similar between OVS7 (54.5%, 250/459) and OVS6 (54.2%, 250/461) groups. The ovulatory response to GnRH2 of OVS was higher in OVS6 (91.3%, 421/461) than OVS7 (84.5%, 388/459). The follicle size (mean +/- standard error of the mean) at the time of TAI was smaller in OVS6 (15.23 +/- 0.11 mm) than OVS7 (16.04 +/- 0.11 mm). When all cows were evaluaed, the pregnancy per AI at 31 d tended to be lower in OVS6 (38.0%, 175/461) than in OVS7 (43.8%, 201/459). Moreover, the pregnancy per AI at 31 d was lower in OVS6 (40.9%, 172/421) compared with OVS7 (50.3%, 195/388) in synchronized cows. In conclusion, although the modified OVS protocol decreased the follicle size at the time of AI and increased the ovulatory response to GnRH2 of OVS, it unexpectedly reduced fertility in cyclic lactating dairy cows.Item Siklik ve siklik olmayan sütçü ineklerde ovsynch protokolüne verilen yanıtın karşılaştırılması(Uludağ Üniversitesi, 2010-11-26) Taşdemir, Umut; Alkan, Ali; Okut, Hayrettin; Keskin, Abdulkadir; Mecitoğlu, Gülnaz Yılmazbaş; Karakaya, Ebru; Gümen, Ahmet; Uludağ Üniversitesi/Veteriner Fakültesi.Ovsynch protokolü, iki GnRH ve bir PGF2α uygulamasından oluşan ve ovulasyonu sinkronize eden zaman ayarlı suni tohumlama (ST) protokolüdür (GnRH–7gün-PGF2α–56saat–GnRH–18 saat-ST). Bu protokolün avantajı, östrus tespitine gerek kalmadan ST’ye olanak sağlamasıdır. Yapılan çalışmalarda Ovsynch protokolü hem siklik hem de siklik olmayan ineklerde ovulasyonu başarılı bir şekilde sinkronize etmesine rağmen, elde edilen gebelik oranlarında farklılıklar mevcuttur. Bu çalışmanın amaçları; 1) siklik olmayan ineklerde Ovsynch öncesi en büyük follikül çapını belirlemek 2) siklik olmayan ineklerde follikül çapının Ovsynch sonuçları üzerine etkisini saptamak 3) siklik ve siklik olmayan ineklerde Ovsynch protokolüne verilen yanıtı karşılaştırmaktı. İneklerin siklik olup olmadıklarını saptamak amacıyla 7 gün arayla iki kez ovaryumların ultrasonografik muayenesi yapıldı. Çalışma, 181 baş siklik, 69 baş ise siklik olmayan toplam 250 baş inekte gerçekleştirildi. Siklik olmayan ineklerde Ovsynch öncesi en büyük follikül çapı 16-24 mm olan inek oranı (%44.9), 9-15 mm (P<0.05; %28.9) ve ≥ 25 mm (P<0.01; %26.0) follikül çaplarına sahip ineklerin oranından daha yüksek saptandı. Ovsynch’in ilk GnRH’na alınan yanıt, siklik olmayan ineklerde (%97.1, 67/69) siklik ineklere (%57.5, 104/181) göre daha fazla saptandı (P<0.0004). Ovsynch’in ikinci GnRH’ına yanıt, siklik (%88.4,160/181) ve siklik olmayan (%85.5, 59/69) ineklerde benzer tespit edildi. Aynı zamanda 31. gün gebelik oranında siklik (%39.8, 72/181) ve siklik olmayan (%31.9, 22/69) inekler arasında fark bulunmadı. Bununla birlikte ≥25 mm follikül çapına sahip siklik olmayan ineklerin Ovsynch’in ikinci GnRH’ına yanıtı ve gebelik oranı (sırasıyla; %100 ve %55.5), follikül çapı 9-15 mm (sırasıyla; %75.0 ve %15.0) ve 16-24 mm (sırasıyla; %83.8 ve %29.0) olan ineklere göre daha yüksek saptandı. Sonuç olarak, siklik olmayan ineklerin Ovsynch protokolüne en az siklik inekler kadar yanıt verdiği ve Ovsynch başlangıcında siklik olmayan ineklerde en büyük follikül çapının ikinci GnRH’a yanıtı ve gebelik oranını etkilediği saptandı.