Browsing by Author "Keskin, Abdülkadir"
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Item Bursa Bölgesindeki süt sığırı işletmelerinde mastitise karşı hipramastivac ile aşılamanın profilaktik etkisi(Uludağ Üniversitesi, 2005) Keskin, Abdülkadir; İntaş, Kamil Seyrek; Uludağ Üniversitesi/Sağlık Bilimleri Enstitüsü/Doğum ve Jinekoloji Anabilim Dalı.Çalışmada polivalan bir mastitis aşısının (Hipramastivac®) saha şartlarında etkinliğinin araştırılması amaçlandı. Daha önce aşı uygulanmamış dört farklı işletmedeki 218 adet sağmal süt sığırı iki gruba ayrılarak aşı (n: 111) ve kontrol grupları (n: 107) oluşturuldu. Çalışma başlangıcında ineklerin bireysel Somatik Hücre Sayıları (SHS), California Mastitis Test (CMT) bulguları ve klinik mastitis vakaları belirlendi. Aşılama sonrası hayvanlar altı ay boyunca takip edilerek yukardaki bulgular yönünden aylık periyotlarda muayene edildi. CMT(+3) ve klinik mastitisli meme loblarından bakteriyolojik incelemeler için süt numuneleri alındı. Çalışma sonunda aşı grubunun somatik hücre sayısı ve CMT’ne göre subklinik mastitis oranı kontrol grubuna göre bir miktar düşük olmakla birlikte, gruplar arasındaki farklılıklar istatistiki açıdan önemsiz bulundu (P>0,05). Aşı grubunda toplam klinik mastitis %26,1, kontrol grubunda %18,7 olarak saptandı. Ancak gruplar arasındaki fark önemsiz bulundu (P>0,05). CMT(+3) pozitif meme loplarından alınan süt numunelerinde aşı ve kontrol grubunda sırasıyla %11,5 ve %15,6 Staphylococcus aureus (S. aureus) belirlendi. Tek kültür ve miks enfeksiyonlar şeklinde memede saptanan toplam Streptecoccus uberis (S. uberis) enfeksiyonu aşı grubunda %6,0 kontrol grubunda %4,3 olarak saptandı. Toplam Koagulaz Negatif Stafilokok (KNS) enfeksiyonu kontrol grubunda %6,2 aşı grubunda %9 olarak tespit edildi. Ancak S. aureus, S. uberis ve KNS enfeksiyonu bakımından gruplar arasında fark belirlenemedi. Aşının diğer komponentlerinin ilgili diğer bakterilere karşı koruma sağlayıp sağlamadığı değerlendirilemedi. Sonuç olarak; aşı grubunda meydana gelen klinik mastitislerin yangı derecesinin daha az ve iyileşme sürecinin daha hızlı olduğu kanısı uyanmakla birlikte, kullanılan polivalan mastitis aşısının mastitise karşı istenen düzeyde etkili olmadığı kanısına varıldı.Publication Butaphosphan and cyanocobalamin treatment of pregnant ewes: Metabolic effects and potential prophylactic effect for pregnancy toxaemia(Elsevier, 2015-04-01) Temizel, Ethem Mutlu; Batmaz, Hasan; Keskin, Abdülkadir; Orman, Abdülkadir; Gençoğlu, Hıdır; Çatık, Serkan; Topal, Onur; TEMİZEL, ETHEM MUTLU; BATMAZ, HASAN; KESKİN, ABDULKADİR; ORMAN, ABDÜLKADİR; GENÇOĞLU, HIDIR; Çatık, Serkan; TOPAL, ONUR; Uludağ Üniversitesi/Veteriner Fakültesi/İç Hastalıkları Anabilim Dalı; 0000-0001-9138-4422; 0000-0002-1933-7354; 0000-0003-1991-8957; HJZ-4775-2023; AAH-1712-2021; AAH-3831-2021; AAG-9134-2021; S-8278-2017; ECV-4083-2022; CHM-0716-2022The effect of administration of butaphosphan and cyanocobalamin on the prophylaxis of pregnancy toxaemia in ewe was investigated. Moreover, the effects of these compounds on body weight gain and biochemical metabolism of pregnant ewe was assessed. A total of 59 pregnant Kivircik crossbred ewes were used in this study. Group I (n: 15) was administered butaphosphan and cyanocobalamin three times before delivery at 1-week intervals. Group II (n: 15) was administered butaphosphan and cyanocobalamin three times before delivery at 3-day intervals. Group III (n: 15) was administered 0.9% NaCl three times before delivery at 1-week intervals. Group IV (n: 14) was administered 0.9%NaCI three times before delivery at 3-day intervals. Six blood samples Were taken from each ewe four times before delivery and two times after delivery. Haematological and biochemical analyses were performed.The levels of BHB and NEFA in groups administered butaphosphan and cyanocobalamin were noticeably lower but there were no statistically significance. Elevated BHB (>0.8 mmol/L), subclinical pregnancies toxaemia were identified in 56.66% in test groups and 72.41% in control groups in all ewes and this was higher in the ewes bearing multiple pregnancies 71.42 in test groups and 82.35% in control groups. Subclinical pregnancy toxaemia in pregnant ewes with twins or triplets is lower than the levels for the control groups, despite the greater lamb counts and weights of the ewes in test groups.Based on our results, it was concluded that the butaphosphan and cyanocobalamin combination could be used as an alternative treatment for the prevention of pregnancy toxaemia. (C) 2015 Elsevier B.V. All rights reserved.Item Clinical laboratory findings, vaginal cytology and pathology in a controlled study of pyometra in cats(Australian Small Animal Veterinary Association, 2005-03) Nak, Deniz; Mısırlıoğlu, Deniz; Nak, Yavuz; Keskin, Abdülkadir; Uludaǧ Üniversitesi/Veterinerlik Fakültesi.; AAH-3831-2021; AAH-5494-2021; 9280090000; 6507455482; 8615464000; 24473229800Pyometra was diagnosed in 17 cats with a mean (+/-SE) age of five years. The most common signs detected by owners included vaginal discharge, anorexia and lethargy. Main clinical findings on physical examination were vaginal discharge, abdominal distention and dehydration. During ultrasonographic examinations, the uteri in cats with pyometra appeared as hypoechoic and anechoic areas with linear and disordered tubular structures. Cats with pyometra were found to have normocytic, normocromic anaemia, leukocytosis, neutrophilia and thrombocytopaenia. In cats with pyometra, decreased ALT levels were recorded compared to the results from healthy cats. Increased parabasal cell density was detected in vaginal cytology. Histopathologic diagnosis of pyometra was classified as types III and IV and most of the ovaries had corpi lutea.Item Comparing conception rate of the repeat breeder vs. normal dairy cows following a combined treatment protocol during the warm season(Wiley, 2010-09) Çevik, Sait; Okut, Hayrettin; Keskin, Abdülkadir; Yılmazbaş, Gülnaz Mecitoğlu; Gümen, Ahmet; Karakaya, Emre; Uludağ Üniversitesi/Veterinerlik Fakültesi/Klinik Bilimler Bölümü.; 0000-0003-2817-3221; AAG-4440-2019; AAH-1406-2021; AAH-3831-2021Item Comparison of responses to Ovsynch between Holstein-Friesian and Swedish Red cows(Elsevier, 2010) Çelik, Yakup; Okut, Hayrettin; Wiltbank, Milo Charles; Keskin, Abdülkadir; Yılmazbaş, Gülnaz Mecitoğlu; Gümen, Ahmet; Karakaya, Ebru Bilen; Uludağ Üniversitesi/Veterinerlik Fakültesi/Klinik Bilimler Bölümü.; 0000-0003-2817-3221; AAH-1406-2021; AAG-4440-2019; AAH-3831-2021; 24473229800; 36457964000; 6602393069; 36457784500The Ovsynch protocol was designed to synchronize ovulation, thereby allowing timed artificial insemination (TAI) of all cows without detection of estrus. However, the effectiveness of Ovsynch in different breeds of dairy cows has not been previously compared. The aim of this study was to compare the response to Ovsynch in cycling lactating Holstein-Friesian (HF) and Swedish Red (SR) dairy cows. A total of 495 cyclic cows (n=347 HF, n=148 SR) were housed together and treated with Ovsynch (GnRH - 7 d - PGF2α - 56h - GnRH - 16 to 18h - TAI). Ovulatory responses, synchronization rate, maximal follicle size at the time of AI, and percentage of pregnant cows per AI (P/AI at 31 and 62 d after AI) were compared between breeds. Ultrasonography was performed during Ovsynch at first GnRH, PGF2α, at time of AI, and 7 d after AI. Ovulatory response and synchronization rate were similar in HF versus SR cows (60.2 vs. 62.2%; 88.4 vs. 88.5%, respectively). Cows that ovulated to the first GnRH of Ovsynch had smaller follicle size at AI (15.9±0.1 vs. 16.4±0.2mm). Maximal follicle size at AI was greater for HF (16.4±2.2mm) than SR (15.5±2.3mm) cows. The P/AI was greater for SR than HF cows at the 62-d pregnancy diagnosis (56.1 vs. 46.1%). In addition, pregnancy loss between 31 and 62 d of pregnancy was greater in HF (10.1%) than SR (3.5%) cows. Fertility was less in HF cows during the hot season (57.7 in cold vs. 38.1% in the hot season), whereas such a decrease was not observed in SR (60.0 in cold vs. 53.5% in the hot season) cows. Thus, although the GnRH treatments of Ovsynch were equally effective in SR and HF cows, pregnancy outcomes (P/AI at d 62 and pregnancy survival) were greater in SR than HF cows, and P/AI in SR cows was not compromised during the hot season as was found for HF cows.Item Comparison of responses to Ovsynch between Holstein-Friesian and Swedish Red cows(Elsevier Science, 2011-04) Çelik, Yakup; Okut, Hayrettin; Wiltbank, Milo Charles; Keskin, Abdülkadir; Mecitoğlu, Gülnaz Yılmazbaş; Gümen, Ahmet; Karakaya, Ebru; Uludağ Üniversitesi/Veterinerlik Fakültesi/Kadın Hastalıkları ve Doğum Anabilim Dalı.; 0000-0003-2817-3221; AAH-1406-2021; AAG-4440-2019; AAH-3831-2021; 24473229800; 36457964000; 6602393069; 36457784500The Ovsynch protocol was designed to synchronize ovulation, thereby allowing timed artificial insemination (TAI) of all cows without detection of estrus. However, the effectiveness of Ovsynch in different breeds of dairy cows has not been previously compared. The aim of this study was to compare the response to Ovsynch in cycling lactating Holstein-Friesian (HF) and Swedish Red (SR) dairy cows. A total of 495 cyclic cows (n = 347 HF, n = 148 SR) were housed together and treated with Ovsynch (GnRH - 7 d - PGF(2 alpha) - 56 h - GnRH - 16 to 18 h - TAI). Ovulatory responses, synchronization rate, maximal follicle size at the time of AI, and percentage of pregnant cows per AI (P/AI at 31 and 62 d after AI) were compared between breeds. Ultrasonography was performed during Ovsynch at first GnRH, PGF(2 alpha), at time of AI, and 7 d after AI. Ovulatory response and synchronization rate were similar in HF versus SR cows (60.2 vs. 62.2%; 88.4 vs. 88.5%, respectively). Cows that ovulated to the first GnRH of Ovsynch had smaller follicle size at AT (15.9 +/- 0.1 vs. 16.4 +/- 0.2 mm). Maximal follicle size at AT was greater for HF (16.4 +/- 2.2 mm) than SR (15.5 +/- 2.3 mm) cows. The P/AI was greater for SR than HF cows at the 62-d pregnancy diagnosis (56.1 vs. 46.1%). In addition, pregnancy loss between 31 and 62 d of pregnancy was greater in HF (10.1%) than SR (3.5%) cows. Fertility was less in HF cows during the hot season (57.7 in cold vs. 38.1% in the hot season), whereas such a decrease was not observed in SR (60.0 in cold vs. 53.5% in the hot season) cows. Thus, although the GnRH treatments of Ovsynch were equally effective in SR and HF cows, pregnancy outcomes (P/AI at d 62 and pregnancy survival) were greater in SR than HF cows, and P/AI in SR cows was not compromised during the hot season as was found for HF cows.Item Comparison of synchronisation and fertility after different modifications of the ovsynch protocol in cyclic dairy cows(Akademiai Kiado Zrt, 2012-12-11) Koç, Volkan; Okut, Hayrettin; Yilmazbaş-Mecitoğlu, Gülnaz; Karakaya-Bilen, Ebru; Keskin, Abdülkadir; Gümen, Ahmet; Uludağ Üniversitesi/Veteriner Fakültesi/Kadın Hastalıkları ve Doğum Anabilim Dalı.; 0000-0003-2817-3221; 0000-0003-4837-1858; AGY-3496-2022; AAG-4440-2019; AAH-1406-2021; AAH-3831-2021; 36457964000; 36457784500; 24473229800; 6602393069The objectives of this study were to evaluate the effects of (1) double doses of PGF(2 alpha) administration or (2) an exogenous progesterone (CIDR) applied concurrently with, or (3) the day after, first GnRH of Ovsynch (GnRH-1), on synchronisation and fertility during the Ovsynch protocol. All cows (n = 378) received the Ovsynch protocol (GnRH-7d-PGF(2 alpha)-56h-GnRH-18h-TAI). The 'OVS' group (n = 105) received only the Ovsynch protocol. The 'OVS-PGF' group (n = 118, GnRH-7d-PGF(2 alpha)-12h-PGF(2 alpha)-44h-GnRH-18h-TAI) received an extra dose of PGF(2 alpha) 12 h later on Day 7. The 'OVS-7CIDR' group (n = 78, GnRH+CIDR-7d-PGF(2 alpha)-56h-GnRH-18h-TAI) received a CIDR for 7 days between GnRH-1 and PGF(2 alpha). In the 'OVS-6CIDR' group (n = 77, GnRH-24h-CIDR-6d-PGF(2 alpha)-56h-GnRH-18h-TAI), CIDR was applied one day after GnRH-1 and removed 6 days later. When all cows were evaluated, the responses to GnRH-2 were higher (P = 0.005) in cows that responded to GnRH-1 (95.4%) compared to the cows that did not respond (87.6%). The pregnancy rates at 31 and 62 days for each group were 48.6% and 42.9% in the OVS, 54.2% and 52.5% in the OVS-PGF, 52.6% and 48.7% in the OVS-7CIDR, and 55.8% and 49.3% in the OVS-6CIDR groups. Thus, none of the three different treatments has an effect on increasing the outcomes of the Ovsynch protocol in cyclic lactating dairy cows.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 following timed artificial insemination protocols in dairy heifers synchronised by PGF(2 alpha) and GnRH(Ankara Üniversitesi, 2011) Taşdemir, Umut; Çelik, Yakup; Güzeloǧlu, Aydın; Mecitoğlu, Gülnaz Yılmazbaş; Keskin, Abdülkadir; Bilen, Ebru Karakaya; Gümen, Ahmet; Uludağ Üniversitesi/Veterinerlik Fakültesi/Kadın Hastalıkları ve Doğum Anabilim Dalı.; 0000-0003-2817-3221; AAH-3831-2021; AAH-1406-2021; AAG-4440-2019; 36457964000; 24473229800; 36457784500; 6602393069This study aimed to develop a timed artificial insemination (TAI) protocol using PGF(2 alpha) and GnRH with acceptable pregnancy rate in dairy heifers. Dairy heifers (n=290), aged between 13 and 26 months (mean 16.1 months), were used in this study. Heifers were synchronized with two PGF(2 alpha) administrations by 14 d intervals. After the second PGF(2 alpha), heifers were randomly assigned into two groups. In Group 1 (n=155), GnRH was given at 56h following 2nd PGF(2 alpha) and TAI was performed at 16-18h after the GnRH. In Group 2 (n=135), GnRH was administered at 72h after 2nd PGF(2 alpha), at the time of TAI. Ultrasonography was performed at both PGF(2 alpha) administrations to determine cyclicity, at the time of TAI to measure ovulatory follicle size, 7 d after TAI to determine ovulation, 31 and 62 d post-AI to determine pregnancy. Ovulatory follicle size at the time of TAI was not significantly different between groups (12.8 +/- 1.6 mm and 13.2 +/- 1.8 mm in group 1 and 2, respectively). Synchronization rate was similar in group 1 (85.2%;132/155) and in group 2 (91.1%;123/135). Conception rate (CR) at 31 d was not different in group 1(59.8%;79/132) and in group 2 (55.3%;68/123). Embryonic loss (7.6%; 6/79 and 7.4%; 5/68 in group 1 and 2 respectively) was not different. Gender ratio of the calves was found different between groups. Proportion of the female calves born were higher (P=0.03) in group 1 (63.3%; 38/60) than in group 2 (42.0%; 21/50). In conclusion, both protocols can be used in order to eliminate estrous detection in large dairy herds. Although GnRH administration at the time of TAI was found to be useful to reduce handling of heifers, GnRH can be applied 16-18 h before Alto achive higher female calves ratio in large dairy farms.Item Dry period management and optimization of post-partum reproductive management in dairy cattle(Wiley, 2011-09) Wiltbank, Milo Charles; Gümen, Ahmet; Keskin, Abdülkadir; Yılmazbaş, Gülnaz Mecitoğlu; Karakaya, Ebru Bilen; Uludağ Üniversitesi/Veterinerlik Fakültesi/Kadın Hastalıkları ve Doğum Anabilim Dalı.; 0000-0003-2817-3221; AAH-1406-2021; AAG-4440-2019; AAH-3831-2021; 6602393069; 24473229800; 36457964000; 36457784500Dry period and early post-partum management are decisive factors for fertility in lactating dairy cows. Previous studies have shown that decreased dry matter intake (DMI) and increased non-esterified fatty acids (NEFA) negatively affect fertility and subsequent milk production. The traditional dry period decreases DMI prior to parturition, resulting in a decrease in energy intake. A negative energy balance increases NEFA concentration, and increased NEFA may impair the immune system, especially by decreasing neutrophil function prior to parturition. Earlier studies have shown that postpartum health disorders, including retained placenta and metritis, were correlated with periparturient neutrophil function. In addition, decreased DMI is also linked to a reduced body condition score (BCS) in dairy cows. These events in the periparturient period negatively affect fertility. Some manipulation, such as shortening the dry period, may be a solution to increased DMI in the periparturient period, preventing postpartum disorders and subsequent fertility issues. This article aims to explain the effects of shortening the dry period on reproduction and early post-partum treatments to improve fertility. In addition, timed artificial insemination protocols will be discussed for use during the post-partum period to improve fertility in dairy cows.Item The effect of early or late breeding on milk production in lactating dairy cows(Wiley, 2008-07) Çelik, Yonca Çağatay; Burucu, Y.; Gümen, Ahmet; Keskin, Abdülkadir; Mecitoğlu, Gülnaz Yılmazbaş; Uludağ Üniversitesi/Veteriner Fakültesi/Jinekoloji Anabilim Dalı.; 0000-0003-2817-3221; AAH-1406-2021; AAH-3831-2021; AAG-4440-2019Item Effect of hCG vs GnRH at the beginning of the ovsynch protocol on ovulation and conception rate in cyclic lactating dairy cows(Wiley, 2009-09) Darıcı, R.; Keskin, Abdülkadir; Mecitoğlu, Gülnaz Yılmazbaş; Gümen, Ahmet; Karakaya, Emre; Uludağ Üniversitesi/Veteriner Fakültesi/Kadın Hastalıkları ve Doğum Anabilim Dalı.; 0000-0003-2817-3221; AAH-1406-2021; AAH-3831-2021; AAG-4440-2019Item Effect of hCG vs. GnRH at the beginning of the Ovsynch on first ovulation and conception rates in cyclic lactating dairy cows(Elsevier, 2010-09-01) Darıcı, R.; Okut, Hayrettin; Keskin, Abdülkadir; Yılmazbaş Mecitoğlu, Gülnaz; Gümen, Ahmet; Karakaya Bilen, Ebru; Uludağ Üniversitesi/Veterinerlik Fakültesi/Klinik Bilimler Bölümü.; 0000-0003-2817-3221; AAH-3831-2021; AAH-1406-2021; AAG-4440-2019; 24473229800; 36457964000; 6602393069; 36457784500Ovulatory response to the first GnRH of Ovsynch is a very important factor for determining the outcome of a successful synchronization. The aim of the present study was to develop a protocol to increase the percentage of cows that ovulated in response to the first administration of Ovsynch. This study was designed to compare ovulation rates in response to GnRH or hCG at the beginning of Ovsynch and to evaluate the effects of this manipulation on pregnancy. Cows (n = 371) with corpus luteum (CL) and at least one follicle greater than 10 mm diameter size on either ovary were included in the study. Cows were divided into two groups. The Ovsynch protocol began with GnRH (10 mu g) in the GPO group (n = 161; GnRH-7d-PGF2 alpha-56h-GnRH-18h-AI), whereas in the HPG group, the first GnRH of the Ovsynch was replaced with 1500 IU hCG (n = 210; hCG-7d-PGF2 alpha-56h-GnRH-18h-AI). Ovarian ultrasonography was performed at the times of GnRH or hCG and of PGF2 alpha administration, at the time of artificial insemination (AI) and seven days after Al, to determine ovulation. Maximal follicle size at the beginning of the Ovsynch did not affect on response to the first GnRH/hCG treatment. Conception rate (31 d) was 0.6 times more likely to be higher (P < 0.001) in cows that responded to the first hormonal administration of Ovsynch than in those that did not respond (95% CI = 0.29-0.71). Conception rate was found to be different between the HPG (37.6%, 79/210) and the GPO groups (48.4%, 78/161). Thus, beginning of the Ovsynch protocol with hCG did not increase ovulation and conception rate in lactating dairy cows, suggesting that hCG is not a suitable replacement of the first GnRH of Ovsynch. However, our results do show that increasing the ovulation rate in response to the first hormonal administration of Ovsynch can have a significant effect on conception rate.Item Effect of post-ai cephapirin on conception rate in repeat breeder cows(Wiley, 2010-09) Çelik, Yakup; Okut, Hayrettin; Yılmazbaş, Gülnaz Mecitoğlu; Keskin, Abdülkadir; Karakaya, Emre; Gümen, Ahmet; Uludağ Üniversitesi/Veterinerlik Fakültesi/Klinik Bilimler Bölümü.; 0000-0003-2817-3221; AAH-3831-2021; AAG-4440-2019; AAH-1406-2021Item 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 GnRH, PGF2α and oxytocin treatments on conception rate at the time of artificial insemination in lactating dairy cows(Czech Academy Agricultural Sciences, 2011) Çevik, Samet; Gümen, Ahmet; Keskin, Abdülkadir; Mecitoğlu, Gülnaz Yılmazbaş; Bilen, Ebru Karakaya; Balcı, Faruk; Uludağ Üniversitesi/Veterinerlik Fakültesi/Kadın Hastalıkları ve Doğum Anabilim Dalı.; Uludağ Üniversitesi/Veterinerlik Fakültesi/Zootekni ve Hayvan Besleme Bölümü.; 0000-0003-2817-3221; AAH-1406-2021; AAG-4440-2019; AAH-3831-2021; 6602393069; 24473229800; 36457964000; 36457784500; 16062981700In several studies, hormones such as gonadotropin-releasing hormone (GnRH), prostaglandins and oxytocin were used to increase pregnancy rate by inducing ovulation and improving the sperm transport in the female reproductive tract in lactating dairy cattle. The objective of this study was to compare the effects of GnRH, prostaglandin F-2 alpha (PGF(2 alpha)) and oxytocin treatments at the time of artificial insemination (AI) after spontaneous oestrus on the conception rate (CR) of lactating dairy cows. Oestrus was detected by visual observations by experienced personnel. All cows (n = 430, 308 Holstein-Frisian and 122 Swedish-Red dairy cows) were inseminated based on the am/pm rule by veterinarians of the farm. After AI, cows were alternately assigned to one of the four treatment groups: (1) GnRH (n = 113); (2) PGF(2 alpha) (n = 106); (3) oxytocin (n = 106) and (4) non-treated control (n = 105). Pregnancy diagnosis was performed 28-34 and 58-64 days post-insemination by transrectal ultrasonography. Conception rates on days 28-34 and 58-64 were not different among GnRH (46.0%; 52/113 and 44.3%; 50/113), PGF(2 alpha) (37.7%; 40/106 and 35.9%; 38/106) and control (49.5%; 52/105 and 47.6%; 50/105) groups. However, conception rates were lower (P = 0.02) in oxytocin (31.1%; 33/106 and 30.2%; 32/106) than in GnRH and control groups on days 28-34 and 58-64. Other covariant factors, such as milk production, days in milk (DIM), breed, parity, service number did not affect the conception rate. Thus, there were no beneficial effects of treatments with GnRH and PGF(2 alpha) at the time of AI, and oxytocin had an adverse effect on CR in lactating dairy cows in this study.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.Item Effects of presynchronizations with GnRH/PGF(2 alpha) vs. progesterone before Ovsynch in noncyclic dairy cows(Elsevier, 2010) Darıcı, R.; Okut, Hayrettin; Yılmazbaş, Gülnaz Mecitoğlu; Keskin, Abdülkadir; Gümen, Ahmet; Karakaya, Ebru; Uludağ Üniversitesi/Veterinerlik Fakültesi/Klinik Bilimler Bölümü.; Uludağ Üniversitesi/Veterinerlik Fakültesi/Klinik Öncesi Bilimler Bölümü.; 0000-0003-2817-3221; AAH-3831-2021; AAH-1406-2021; AAG-4440-2019Item Effects of reducing interval from GnRH to PGF(2 alpha) in Ovsynch protocol on pregnancy rate in cyclic lactating dairy cows(Elsevier, 2010) Çelik, Yakup; Okut, Hayrettin; Gümen, Ahmet; Yılmazbaş, Gülnaz Mecitoğlu; Keskin, Abdülkadir; Karakaya, Emre; Uludağ Üniversitesi/Veterinerlik Fakültesi/Klinik Bilimler Bölümü.; Uludağ Üniversitesi/Veterinerlik Fakültesi/Klinik Öncesi Bilimler Bölümü.; 0000-0003-2817-3221; AAG-4440-2019; AAH-1406-2021; AAH-3831-2021Item The effects of varying levels of dietary starch on reproductive traits in lactating dairy cows(TÜBİTAK, 2015-11-26) Keskin, Abdülkadir; Gençoğlu, Hıdır; Mecitoğlu, Gülnaz; Çetin, İsmail; Kara, Çağdaş; Udum, Duygu Küçükşen; Bilen, Ebru; Güner, Barış; Orman, Abdülkadir; Gümen, Ahmet; Uludağ Üniversitesi/Veteriner Fakültesi/Jinekoloji Anabilim Dalı.; Uludağ Üniversitesi/Veteriner Fakültesi/Hayvan Besleme ve Beslenme Hastalıkları Anabilim Dalı.; Uludağ Üniversitesi/Veteriner Fakültesi/Biyokimya Anabilim Dalı.; 0000-0003-4837-1858; 0000-0003-2817-3221; 0000-0001-9138-4422; AIF-3815-2022; AAH-3831-2021; AGY-3496-2022; HJZ-4775-2023; AAH-1406-2021; AAG-4440-2019; AAG-9134-2021; 24473229800; 15753357900; 36457964000; 56707038100; 31967678500; 31967936400; 57040965000; 57188841418; 24335834100; 6602393069The aim of this study was to determine the effects of three different dietary starch levels on postpartum milk yield, blood metabolites, and reproductive traits in cows. A total of 23 primiparous Holstein-Friesian cows were fed three different diets including different starch levels on a dry matter basis from parturition until day 80. Cows were randomly assigned into the three groups according to the starch levels: low (LS, 16%, n = 7), medium (MS, 20%, n = 8), and high (HS, 24%, n = 8). Milk yields were recorded daily, and body condition score (BCS) was determined every week. Transrectal ultrasonography was performed, and blood samples were taken three times each week to determine reproductive traits and blood metabolites. Although the milk yield was greater in the LS group compared to the other groups, BCS and blood metabolites did not differ among the groups. The postpartum follicular patterns, times of first postpartum ovulation, and involution processes did not differ among the groups. In addition, the ovulatory follicle and corpus luteum sizes and the progesterone levels after induced estrus were numerically greater in HS than other groups. Thus, there were no effects of starch levels on postpartum reproductive traits.