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Öğe Boğaların potansiyel fertilitelerinin belirlenmesinde yeni bir servikal mukus penetrasyon test tekniği (Payet yöntemi)(2006) İleri, İrfan Kamuran; Bacınoğlu, Süleyman; Ak, Kemal; Cirit, Ümit; Taş, MuzafferBu çalışmada boğaların potansiyel fertilitelerinin belirlenmesinde kullanılabilecek yeni bir servikal mukus penetrasyon test (CMPT) tekniği geliştirildi.Araştırmanın ilk aşamasında 10 Holstein boğanın dondurulmuş spermaları ile suni tohumlamalar yapıldı. Ortalama non return rate (NRR) değerleri arasında istatistiksel farklılık bulunan ilk 3 ve son 3 sıradaki boğalar sırasıyla yüksek ve düşük fertilite gruplarını oluşturdu ve dondurulmuş spermaları çalışmanın 2. aşamasında (CMPT) kullanıldı. Yaygın olarak kullanılan CMPT yöntemlerinden farklı olarak servikal mukus 0.25 ml’lik şeffaf payetlere çekildi. Daha sonra eritilmiş sperma ile 3 farklı ısı (37, 39 ve 41ºC) ve iki farklı sürede (15 ve 45 dakika) inkübasyona tabi tutuldu. İnkübasyonlardan sonra payetler, sıvı azot buharında dondurularak -20ºC’de saklandı. İnceleme gününde payetlerin uç kısmından itibaren ölçülerek 15–17.5 mm (1. penetrasyon aralığı; PA1), 32.5–35 mm (PA2) ve 50–52.5 mm’ler (PA3) arasındaki 2.5’er mm’lik parçalar kesilerek ayrıldı. Daha sonra kesilen parçalar içerisindeki mukus bir tel vasıtasıyla itilerek donmuş halde lamlar üzerine aktarıldı ve lamel kapatılarak faz-kontrast mikroskop (200x) spermatozoonlar sayıldı.Boğaların bireysel NRR skorları ile PA 3’te saptanan spermatozoon sayıları (P<0.05) ve motilite (P<0.01) arasında önemli derecede pozitif, akrozomal bozukluk (P<0.01), diğer morfolojik bozukluk (P<0.01) ve toplam morfolojik bozukluk oranları (P<0.01) arasında negatif korelasyon bulundu. Ayrıca 41ºC ısı ve 15 dakika sürede yapılan inkübasyonda düşük fertilite grubuna oranla yüksek fertilite grubunda PA 3’te önemli derecede daha fazla sayıda spermatozoon saptandı (P<0.01).Bu çalışmadan, (a) rutin spermatolojik testlerle kombine bir şekilde bu yeni CMPT yönteminin boğaların potansiyel fertilitelerinin belirlenmesinde kullanılabileceği ve (b) uzak bölgedeki penetrasyon aralığının (PA3), yüksek inkübasyon ısısının (41ºC) ve kısa inkübasyon süresinin (15 dk) test sonuçlarını daha da belirginleştirdiği sonuçları çıkarıldı.Öğe The effects of a low dose of cabergoline on induction of estrus and pregnancy rates in anestrous bitches(Elsevier Science Bv, 2007) Cirit, Umut; Bacinoglu, Suleyman; Cangul, I. Taci; Kaya, Huriye Horoz; Tas, Muzaffer; Ak, KemalThis is the first report of successful induction of normal estrus and ovulation in breeder bitches with as a low dose as 0.6 mu g/kg/day of cabergoline formulation marketed for use in women. Sixty-one pure breed bitches from various breeds were used in the study at their already determined periods of anestrus. Twenty-four dogs formed the control group, while 37 bitches were administered with two different doses of cabergoline (recommended dose group, n = 10, 5 mu g/kg/day and low dose group, n = 27, 0.6 mu g/kg/day). Induced estrus rates and mean treatment and proestrus durations of dogs in these two dose groups were compared. At the second phase of the study, the effects of 500 IU human chorionic gonadotropin (hCG) administered on days 1 and 3 of estrus induced by the low dose of cabergoline, on the duration of behavioral estrus, ovulation rates, pregnancy rates and the number of offspring were investigated. For this purpose, the dogs with signs of proestrus (22/27) following the treatment in the low dose group were assigned into two subgroups. Five hundred IU of hCG (Pregnyl, Organon, Turkey) was intramuscularly administered to eight of these dogs [low dose (hCG+) group] on days 1between days 8-45 and 4-48 (mean: 23.63 +/- 14.33 and 24.41 +/- 14.31 days), in the ratio of 80.0 and 81.5%, respectively (p > 0.05). In both dose groups, post-treatment interestrous intervals were significantly shorter than both those of the control group and their own pre-treatment interestrous intervals (p < 0.05). Ovulation rates, pregnancy rates and mean number of offspring delivered by the dogs in the recommended dose, low dose (hCG-), low dose (hCG+) and control groups were found to be similar (p > 0.05). However, the mean duration of behavioral estrus of the dogs in the low dose (hCG+) group was found to be significantly longer compared to dogs in all other groups (p < 0.05). In both dose groups, no correlation could be found between the anestrus stages and treatment durations (p > 0.05). Shortly, it has been concluded from the study that (1) normal and fertile estrus can be induced more economically in bitches during different stages of anestrus using as a low dose of 0.6 mu g/kg of cabergoline formulation marketed for use in women, and that (2) hCG injections on days 1 and 3 of the estrus induced by this method has no positive effects on the ovulation rates, pregnancy rates and the number of offspring per pregnancy. (C) 2006 Elsevier B.V. All rights reserved. and 3 of estrus. The remaining 14 dogs were not treated with hCG [low dose (hCG-) group]. An aqueous solution of cabergoline (Dostinex, Pharmacia, Italy) was orally administered until 2 day after the onset of proestrus or for a maximum of 42 days. Blood samples were taken daily from all treatment and 11 control bitches during the first five days of behavioral estrus to measure progesterone concentrations. In the recommended dose and low dose groups, estrus was inducedÖğe Effects of cooling rate on membrane integrity and motility parameters of cryopreserved ram spermatozoa(2015) Pabuccuoğlu, Serhat; Cirit, Ümit; Demir, Kamber; Birler, Sema; Bozkurt, H. Hakan; Ak, Kemal; Bakırer, Gül ÖztürkBu çalışmada koç spermasının 26°Cden +5°Cye indirilmesinde farklı soğutma hızlarının (0.3°C/dk., 0.6°C/dk. ve 0.9°C/dk.) eritme sonrasıspermatolojik özellikler ve spermatozoonların ultrastrüktürel yapısı üzerindeki etkilerinin incelenmesi amaçlanmıştır. Altı adet koçtan elektroejakülatörle alınan spermalar 26°Cdaki su banyosunda pooling işlemine tabii tutuldu. Tris bazlı sulandırıcıyla sulandırılan birleştirilmiş sperma üç eşithacme bölünerek 3 farklı hızda (0.3, 0.6 ve 0.9°C/dk.) +5°C ye soğutuldu. Sperma iki basamakta sulandırıldı, gliserol sperma ısısının +5°Cye indiğiikinci basamakta katıldı. Sulandırma sonrası sperma 1 saat ekilibre edildi daha sonrasında 0.25 ml payetlere çekilerek sıvı azot buharında donduruldu.Sperma pooling, sulandırma, soğutma, ekilibrasyon ve eritme sonrası gibi tüm aşamalarında motilite değerleri Bilgisayar Destekli Analiz Sistemleri(CASA) ile değerlendirildi. Pooling ve soğutma sonrasında elektron mikroskop incelemeleri gerçekleştirildi. 0.3°C/dk. soğutma grubunun, spermanın+5°Cye soğutma, ekilibrasyon ve eritme sonrasındaki hem total motilite hem de progressive motilite değerleri 0.9°C/dk. soğutma grubuna göre önemliderecede yüksek bulundu (P<0.05). Bu grup 0.6°C/dk soğutma hızı ile karşılaştırıldığında ise, 0.3°C/dk. soğutma grubunun soğutma ve ekilibrasyonsonrasındaki total motilite değerleri yüksek bulundu ancak eritme sonrası gruplar arasında fark bulunmadı (P>0.05). Soğutma ve eritme sonrasında iseprogressive motilite değerleri daha yüksek bulunurken(P<0.05), ekilibrasyon aşamasında progresif motilite değerleri arasında fark bulunmadı(P>0.05).Yapılan TEM incelemesinde, tüm soğutma hızı gruplarında eritme sonrasında tespit edilen toplam hasarlı spermatozoit oranı, pooling sonrasına göreönemli derecede yüksek bulunmuştur (P<0.05). Sonuç olarak koç spermasının dondurulması öncesinde +5°Cye soğutulmasında 0.3°C/dk.nın üzerindesoğutma hızlarının kullanılmasının sperma kalitesini olumsuz etkilediği ve soğutma hızı 0.6 ve 0.9°C/dk.ya arttırıldıkça eritme sonrası total ve progresifmotilitenin artan oranlarda etkilendiği sonucu çıkarılmıştır. Ayrıca, koç spermasında düşük sıcaklara bağlı olarak oluşan ultra strüktürel hasarların ilksulandırma aşamasından itibaren başladığı ve ultra strüktürel hasarların, spermanın gördüğü işleme ve soğutma hızlarına göre başın farklı bölgelerindelokalize olma eğiliminde olduğu sonucu çıkarılmıştır.Öğe Effects of Cooling Rate on Membrane Integrity and Motility Parameters of Cryopreserved Ram Spermatozoa(Kafkas Univ, Veteriner Fakultesi Dergisi, 2015) Demir, Kamber; Bakirer Ozturk, Gul; Cirit, Umit; Bozkurt, H. Hakan; Aktas, Abit; Birler, Sema; Ak, KemalIn this study we aimed to determinate the effects of three different cooling rates from +26 degrees C to +5 degrees C at (0.3 degrees C/min 0.6 degrees C/min and 0.9 degrees C/min) on spermatologic and ultrastructure properties of ram semen. For this purpose semen from 6 rams was collected by electroejaculator and was pooled in a +26 degrees C waterbath. Pooled semen was diluated with tris based extender and divided into three equal parts according cooling rates (0.3 degrees C/min., 0.6 degrees C/min. and 0.9 degrees C/min). Cooled semen was reextended with extender B +5 degrees C in the second step. Diluated samples were equilibrated for 1 h and then were loaded in 0.25 mL straws and freezed in liquid nitrogen vapor. After each freezing stage semen was evaluated motility with computer-assisted semen analysis (CASA). Electron microscobic evaluation was done for pooled and chilled samples. It has been observed that 0.3 degrees C/min. cooled group had meaningfully higher values of motility and progressive motility at +5 degrees C after equilibration and post-thaw stages when compared with the 0.9 degrees C/min. group (P<0.05). When compared to the 0.6 degrees C/min., the 0.3 degrees C/min. cooled group had higher total motility values at after cooling to +5 degrees C (P<0.05), equilibration (P<0.05) and post thaw stages (P>0.05) and had higher progressive motility at after cooling to + 5 degrees C (P<0.05), equilibration (P>0.05) and post-thaw stage (P<0.05). The TEM evaluation showed that at cooling to the +5 degrees C increases the total damaged spermatozoa in all groups (P<0.05). In conclusion, cooling the ram semen to +5 degrees C with a rate above 0.3 degrees C/min. affected negatively the spermatological characteristics. Reaching the cooling rates of 0.6 and 0.9 degrees C/min. increasingly deteriorated the post-thaw motility and progressive motility values. Also, low temperature related to ultrastructural damage was observed at the first dilution step and localized at different regions of the sperm head depends upon the processes and cooling rates.Öğe Evaluation of short estrus synchronization methods in dairy cows(Elsevier, 2008) Cirit, Uemuet; Bacinoglu, Suleyman; Tas, Muzaffer; Demir, Kamber; Bas, Ahmet; Ak, Kemal; Ileri, Irfan KamuranIn the present study, two new short estrus synchronization methods have been developed for lactating dairy cows. The study was completed in three consecutive phases. In experiment (Exp) 1, 32 cows, that were not detected in estrus since calving between the 50th and 84th post-partum days, were treated with PGF2 alpha (PGF, D-Cloprostenol, 0.150 mg), estradiol propionate (EP, 2 mg) and GnRH (lecirelina, 50 mu g) at 24 h intervals, respectively, and timed artificial insemination (TAI) was performed 48 h after PGF. Different from Exp 1, EP and GnRH were given at 48 and 60 h, respectively after PGF in Exp 2 (n = 20), instead of 24 and 48 h. Ovulations were investigated by ultrasound for 7 days starting from the day of PGF treatment, and ovulation rates were compared with the ones obtained in Exp 1. In Exp 3, cows were given the same treatments as Exp 2, but treatments started at certain estrus stages. Cows detected in estrus and with a confirmed ovulation (n = 27) after the second PGF given 11 days apart were assigned to three treatment groups. Treatment was initiated at Day 3 (group metestrus, n = 9), Day 12 (group diestrus, n = 9) and Day 18 (group proestrus, n = 9) after ovulation. All cows included in Exp 3 were TAI between 16 and 20 h after GnRH treatment. In Exp 2 and 3, blood samples were obtained once every 2 days, starting from Day 0 to the 10th day after GnRH injection, and once every 4 days between the 10th and the 22nd days after GnRH to examine post-treatment luteal development. During the study, animals exhibiting natural estrus were inseminated and served as controls (n = 85). The rate of estrus was found to be significantly higher in cows with an active corpus luteum (CL) at the start of Exp 1 (72.7% vs. 30.0%, P < 0.05) and the pregnancy rate tended to be higher than cows without an active CL (40.9% vs. 10.0%, P = 0.08). Compared to those in Exp 1, cows in Exp 2 had higher rates of synchronized ovulation (94.1% vs. 59.1%, P = 0.013), In Exp 3, estrus (P < 0.001) and pregnancy rates (P = 0.01) were found to be significantly higher in cows in the proestrus group than in those in the metestrus group. Comparable pregnancy rates were obtained from the first and second inseminations in Exp 1 and 3 with results from those inseminated at natural estrus (P > 0.05). It was concluded from the study that the treatment in Exp 1 and 3 could result in comparable pregnancy rates after timed Al of lactating dairy cows at random stages of the estrus cycle relating to those inseminated at natural estrus, but the stage of the estrus cycle can have significant effects on pregnancy rates. (C) 2007 Elsevier B.V. All rights reserved.Öğe Evaluation of synergic effects of iodixanol and trehalose on cryosurvival of electroejaculated ram semen(Wiley, 2020) Ozmen, Mehmet Ferit; Cirit, Umut; Arici, Ramazan; Demir, Kamber; Kurt, Dogan; Pabuccuoglu, Serhat; Ak, KemalThe primary aim of the study was to investigate whether iodixanol and trehalose would have a synergic effect on the cryosurvival of electroejaculated ram semen. Tris-based diluter was used to prepare 9 different extenders by the addition of iodixanol or trehalose alone or varying combinations of these substances. Diluters were prepared as follows: Tris (control), Io5 (5% iodixanol), Tr25 (25 mmol/L trehalose), Tr50 (50 mmol/L trehalose), Tr50 + Io1.25 (50 mmol/L trehalose and 1.25% iodixanol), Tr50 + Io2.5 (50 mmol/L trehalose and 2.5% iodixanol), Tr50 + Io5 (50 mmol/L trehalose and 5% iodixanol), Tr25 + Io5 (25 mmol/L trehalose and 5% iodixanol) and Tr12.5 + Io5 (12.5 mmol/L trehalose and 5% iodixanol). Supplementation of the freezing extender with trehalose or iodixanol alone supported the protection of both morphological and functional integrity of ram spermatozoa and total motility at 1 and 4 hr post-thawing respectively. However, beyond these positive effects, the combination of trehalose (25 mmol/L) and iodixanol (5%) significantly increased post-thaw sperm longevity and motion properties at the end of 4-hr incubation. The results of the study clearly showed that there was positive synergic effect of iodixanol and trehalose on cryosurvival of ram semen.Öğe İn vitro elde edilen sığır embriyolarının dondurulmasında vitrifikasyon medyumuna maruz kalma sürelerinin çözünme sonrası gelişim üzerine etkisi(2012) Pabuccuoğlu, Serhat; Alkan, Serhat; Demir, Kamber; Ak, Kemal; Cirit, Ümüt; Özdaş, Özen Banu; İrez, TülayGünümüzde dondurulmuş embriyoların transferi ile üstün verim özelliklerine sahip sürülerin oluşturulması, hastalıkların kontrolü ve genetik materyallerin uzun süre saklanması mümkün olabilmektedir. Ancak donmuş embriyolarda eritme sonrası tranfer edilebilir embriyo eldesi ve gebelik oranları istenilen düzeyde değildir. Özellikle embriyoların dondurulması sırasında dejenerasyonlar oluşmaktadır. Dejenerasyonların, embriyoların kriyoprotektif maddelere maruz kalma süreleri ile toksik etkilerinden meydana geldiği düşünülmektedir. Çalışmada mezbahada kesilen sığırların ovaryumları kullanıldı. Aspirasyon yöntemi ile elde edilen oositler (1290 adet) TCM-199 da 22-24 saat süreyle %5 CO2, %5 O2, %90N2 gaz atmosferinde 38,8 ºC de in vitro olarak olgunlaştırıldılar. Olgun oositler IVFTALP medyumunda 18-24 saat süreyle fertilize edildiler. Fertilizasyon sonrası 48. saatte cleavage %67,05 (865/1290) saptandı. Embriyolar %10 FCS’li SOF medyumunda 7 gün süreyle %5 CO2, %5 O2, %90N2 gaz karışımında blastosist (%34,91; 302/865) aşamasına kadar inkübe edildiler. Erken blastosist-blastosist aşamasına ulaşan 302 adet embriyodan 254 tanesi vitrifikasyon solüsyonunda farklı sürelere (15, 30, 60, 90 sn) maruz bırakılarak donduruldular. Bu amaçla sırasıyla 4 grup oluşturuldu. Her grup sırasıyla 67, 64, 63 ve 60 embriyo içerdi (Grup 1, 2, 3, 4). Embriyolar önce % 10 Gliserol + % 10 FCS içeren PBS solüsyonunda (Vs1) 5 dk, sonra %10 Gliserol + %10 FCS+ %20 Etilen Glikollü PBS’de (Vs2) 5 dk. bekletildiler. Daha sonra embriyolar payet içindeki %25 Gliserol + %20 Etilen Glikol + %10 FCS + 0,1 M Sükroz vitrifikasyon solüsyonuna (Vs3) aktarıldılar ve değişik sürelere (15, 30, 60, 90 sn) maruz bırakıldıktan sonra sıvı azota daldırılarak donduruldular. Eritme sonrası (37ºC) embriyolar birkaç kez yıkama medyumunda ve SOF medyumunda yıkandıktan sonra, her bir gruba ait embriyolar 48 saat süreyle tekrar inkübe edildiler. Çalışmada istatistiki analizde ki-kare testi kullanıldı. Eritme sonrası, genişlemiş blastosist-zonadan çıkma safhasında en iyi gelişim %52,2 (35/67) ile Grup 1 de saptanırken, bunu %45,3 (29/64) ile Grup 2, %22,2 (14/63) ile Grup 3 ve %5 (3/60) ile Grup 4 takip etti. Grup I ve II arasında istatiksel bir fark bulunmadı. Grup 1 ile Grup 3 arasındaki istatistiksel fark P<0,01, Grup 1 ile Grup 4 arasında ise P<0,001 düzeyinde anlamlı bulundu.Öğe The potential fertility estimation capacity of the hypoosmotic swelling test, the thermal stress test and a modified cervical mucus penetration test in the bovine(Elsevier Science Bv, 2008) Bacinoglu, Suleyman; Tas, Muzaffer; Cirit, Umut; Ozdas, Ozen Banu; Ak, KemalIn this study, hypoosmotic swelling (HOS), thermal stress (TS) and modified cervical mucus penetration (mCMP) tests have been used with routine tests for the assessment of semen quality. This is the first study in which the comparison of potential fertility estimation of fore-mention three tests was performed. Bull semen samples were divided into two fertility groups (high: n = 3, low: n = 3), according to their post-insemination NRR (non-return rate). Prior to the tests, post-thawed spermatological characteristics were assessed after which HOS, TS and mCMP tests were carried out. In the HOS test, the ratio of swollen cells, in the TS test the motility, and in the mCMP test the number of spermatozoa penetrating the cervical mucus, were examined. The relationship between the tests and fertility was also evaluated. HOS test was carried out according to different incubation times and temperatures (37 degrees C 60 min/41 degrees C 15 min/41 degrees C 30 min/46 degrees C 15 min/46 degrees C 30 min). For TS test, samples were subjected to various temperatures for different periods (no incubation (37 degrees C)/41 degrees C 15 min/41 degrees C 30 min/46 degrees C 15 min/46 degrees C 30 min). The mCMP test were subjected to various temperatures for the same period (37 degrees C 15 min/41 degrees C 15 min). In this study, post-thawed motility was found to be similar in high and low fertility groups. However, it has been determined that acrosomal (p < 0.01) and other morphological defects (p < 0.05) were low in the high fertility group. When HOS test was carried out at 37 degrees C, no difference was observed between the bulls with high and low fertility, but at 41 and 46 degrees C, results of high fertility group were significantly higher than those of low fertility group (p < 0.01). Similarly in TS test, the progressive motility rates of high fertility bulls was higher after thermal practices at 41 and 46 degrees C (p < 0.01). In mCMP test, at 37 degrees C, the number of cells that had penetrated was similar. However, significant differences were observed in the incubation at 41 degrees C (p < 0.01). It has been concluded that for the estimation of potential fertility of bulls, HOS, TS and mCMP tests, in combination with routine spermatological tests can be used and the use of further penetration distance range (PDR2) in mCMP test and higher temperatures such as 41 degrees C instead of 37 degrees C, during the incubations in the afore-mentioned performance tests, is more determinative. (C) 2007 Elsevier B.V. All rights reserved.Öğe Relationship between bovine fertility and the number of spermatozoa penetrating the cervical mucus within straws(Elsevier Science Bv, 2007) Tas, Muzaffer; Bacinoglu, Suleyman; Cirit, Umut; Ozdas, Ozen Banu; Ak, KemalIn this study, by using a recently developed test technique, the relationship between the total spermatozoa number penetrating determined sites of bovine cervical mucus in straws and potential fertility of bulls, and other spermatological characteristics were investigated. Furthermore, we aimed to determine the effect on the test results, of two different incubation temperatures (37 and 41 degrees C) and two sperm penetration distance ranges (PDRs). Frozen semen samples of six Holstein bulls were used in the study. The bulls were divided into two fertility groups (high and low fertility) according to the non-return rates (NRR). For the penetration test, cervical mucus was drawn into transparent plastic straws and incubated with semen at 37 and 41 degrees C for 15 min. After the incubation, straws were frozen in liquid nitrogen vapour and stored at -20 degrees C. On the evaluation day, concentrations of spermatozoa penetrated to the PDRs, each of which was 2.5 mm, between 32.5 and 35 mm (first penetration distance range, PDR1), and 50 and 52.5 mm (second penetration distance range, PDR2) distance in the straws from the open end, were measured. When compared with the low fertility group, bulls from the high fertility group showed a higher number of spermatozoa at the determined PDRs, and a significant positive correlation was found between the total number of spermatozoa at the penetration distances and the NRR scores of the bulls. (C) 2006 Elsevier B.V. All rights reserved.
