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Öğe Comparison of blood metabolites and GSH-Px, SOD, MDA levels as a predictor of pregnancy in primiparous cows after the Presynch-Ovsynch protocol(Sivar-Soc Italiana Veterinari Animali Reddito, 2022) Yazlik, Murat Onur; Kurt, Serdal; Terzi, Osman Safa; Kaya, Ufuk; Olgac, Kemal TunaThe reactive oxygen species level and antioxidants have determinative roles in gamete development, steroid synthesis and fertilization. The objective of the current study was to compare some metabolic and antioxidant parameters in primiparous cows with and without pregnancy after the presynch-ovsynch protocol in the postpartum period. Sixty dairy cows were allocated to two groups according to their pregnancy status after timed artificial insemination following the presynch-ovsynch protocol. Blood samples were collected at the day of presynch-ovsynch protocol started, at AI and at pregnancy examination to determine glucose, urea, total protein, phosphorus and calcium, GSH-Px, SOD and MDA levels. Receiver operating characteristics (ROC) curves were used to determine the cow-level thresholds for the subsequently pregnant. Moreover, pairwise comparisons were made of the area under the curve (AUC) of ROC curves for the thresholds of GSH-Px, SOD and MDA for identifying the cows most likely to conceive. The biochemical metabolites were in physiological ranges. Serum glucose concentration was greater at the beginning of presynch-ovcsynch in cows that became subsequently pregnant. An interaction was noted between group x time for serum SOD, MDA and GSH-Px levels. The MDA concentration was lower before the synchronization protocol in cows that became subsequently pregnant. Although GSH-Px concentration was greater, SOD was lower after the synchronization sampling time in cows that became subsequently pregnant. MDA and SOD concentrations changed over time in cows that became subsequently pregnant. MDA level at the beginning of synchronization was the best predictor for identifying the cows most likely to conceive with AUC values of 0.866. In conclusion, while presynchronization MDA and post synchronization SOD were lower, post synchronization GSH-Px were higher in pregnant cows. MDA level at the beginning of presynch-ovsynch was the only risk factor for pregnancy. Thus, MDA levels before the synchronization might be used as a biomarker for selecting the cows for presynch-ovsynch protocol.Öğe Determination of expression patterns of miR-26a, and preimplantation factor levels for early pregnancy detection in nulliparous and multiparous cows(Wiley, 2024) Olgac, Kemal Tuna; Yazlik, Murat Onur; Ozkan, Huseyin; Kaya, Ufuk; Tirpan, Mehmet BorgaFor maximum productivity in a dairy farm, the earliest and the most accurate detection of pregnancy is essential. The aim of this study was to determine the efficacy of expression patterns of miR-26a, and serum Preimplantation Factor (PIF) levels for pregnancy diagnosis during the early pregnancy in nulliparous and multiparous cows. A total of 60 cows (30 nulliparous and 30 multiparous Holstein cows) were enrolled in the study. Blood samples were collected for miR-26a on days 8 and 16 (D8 and D16), and for the PIF on days 10 and 20 (D10 and D20) following insemination (D0). Pregnancies were determined by ultrasonography on the 28th day after insemination. Expression levels of miR-26a determined by qPCR. PIF levels were assessed by using commercial ELISA kits. All data were analyzed by using the MIXED procedure of SPSS. The expression levels of miR-26a were 6.64 folds higher on D16 in pregnant compared to non-pregnant multiparous cows (p < .05). On D8 and D16, miR-26a expression levels were found higher 13 folds in pregnant compared to non-pregnant nulliparous cows (p < .05). Additionally, miR-26a expressions were higher 5.42 folds (p < .05) on D8, 7.19 folds higher (p < .01) on D16 in pregnant nulliparous and multiparous cows, and were 6.30 folds higher (p < .001) on D8 and D16 according to non-pregnant animals. PIF levels were greater in pregnant animals (p < .05). Analyzing miR-26a on D8 might be considered as sufficient in nulliparous cows. Pregnancy detection in multiparous cows can be made on the 16th day with this method. Furthermore, PIF evaluations may be sufficient on D10 in multiparous cows. Besides, PIF levels and miR-26a expression levels might be used safely in field conditions and clinical applications.Öğe Effects of vitamin B1, vitamin E and selenium on pregnancy and blood metabolites profile during non-breeding season and early prediction of pregnancy by thermographic monitoring in Merino ewes(Indian Counc Agricultural Res, 2020) Yazlik, Murat Onur; Olgac, Kemal Tuna; Colakoglu, Hatice Esra; Kaya, Ufuk; Yildirim, Merve Menekse; Bas, BulentThe objective of this study was to evaluate the effects of injectable selenium, vitamin E and vitamin B compounds on serum metabolic profile and pregnancy rates (PR) during the non-breeding season in Merino ewes that were synchronized with progesterone and equine chorionic gonadotrophin (eCG). Thermographic monitoring of ewes on the last day of synchronization was successful in the early selection of ewes to be used in artificial insemination and its relationship with pregnancy outcomes. Cyclic and non-pregnant ewes (n=75) were randomly assigned to treatment (n=30) and control (n=45) groups. All animals were synchronized using PGF(2)alpha at day 0. progesterone impregnated intravaginal sponges for 14 days, eCG 48 h before sponge withdrawal and artificial insemination were carried out 43-45 h after sponge removal. Animals of treatment group (n=30) were administered (intramuscularly) with 1 mg sodium selenite, 60 mg vitamin E and 40 mg vitamin B-1 on two occasions, at the beginning of sponge insertion and following sponge removal. Blood samples were collected at sponge insertion and removal. Perianal and perivulvar areas were considered to evaluate the thermal pattern at day 0 and 14 using a thermo camera. Overall, 90.6% of ewes exhibited estrus in response to the synchronization protocol. Ewes of treatment group showed greater PR as compared to that of control group (70.3% vs 56%). Perivulvar temperature was influenced by time only. At the time of sponge removal, perivulvar temperatures were significantly lower in pregnant ewes than in non-pregnant animals. In conclusion, injectable selenium, vitamin E and vitamin B-1 compounds increased PR after synchronization protocol and thermographic evaluation that was performed on the last day of synchronization could be used for very early prediction of pregnancy.Öğe Fertility comparison of frozen bull semen stored in cryogenic deep freezer (-152 °C) and LN2 container(Elsevier Science Inc, 2022) Tirpan, Mehmet Borga; Olgac, Kemal Tuna; Korkmaz, Firat; Sonat, Ali; Kaya, Ufuk; Akcay, ErgunThe present study aimed to use cryogenic deep freezers that could be a feasible alternative for cryopreserved semen storage. A total of 284 straws from three Simmental bulls and 272 Simmental cows were used. The experimental group consisted of 151 semen straws that were stored at -152 & DEG;C for a week. Moreover, the control group consisted of 133 semen straws that were stored at -196 & DEG;C. Firstly, two samples per bull (n = 6) were examined in terms of sperm kinetic parameters by CASA. Furthermore, plasma membrane, acrosome integrity (PMAI) and high mitochondrial membrane potential (HMMP) were analyzed by flow cytometry. Then, artificial inseminations were performed on Simmental cows with 272 straws belonging to two groups. Then, 56th-day Non-return Rate (NRR56) was determined. All spermatological data were subjected to a linear mixed model. Chi-Square test was performed to NRR56 between storage temperature groups. Also, logistic regression analysis was used to examine the effect of bull, storage temperature and age of cows on pregnancy status. While age of cows was included in the final logistic regression model, effect of bull x storage temperature was not included because it was found as non-significant. The post-thaw PMOT and STR of cryopreserved bull semen, which was stored at -152 & DEG;C, had lower and statistically significant values (p < 0.05). However, frozen bull semen, which were stored at -152 & DEG;C, kept its fertility ability as which stored at -196 & DEG;C. Besides, NRR56 of semen stored at -152 & DEG;C and -196 & DEG;C were detected as 57.24% (83/145) and 55.91% (71/127), respectively (p > 0.05). Nevertheless, these results should be supplemented with more pre-freezing and post-thaw sperm quality analyses and more fertility data for increasing the accuracy of the method. (C)& nbsp;2022 Elsevier Inc. All rights reserved.Öğe Pregnancy rates according to follicle diameter and uterus edema in different age groups in two consecutive ovulations in Arabian mares(Univ Zagreb Vet Faculty, 2024) Tirpan, Mehmet Borga; Olgac, Kemal Tuna; Sahin, Mustafa Oguzhan; Kaya, UfukThe study aimed to evaluate the pregnancy rates of mares in different age groups based on follicle diameter and uterine edema during two consecutive ovulations in three breeding seasons. Thirty Arabian mares were divided into two groups: below and equal to 10 years (Group A=54) and above 10 years old (Group B=36). Throughout the breeding season, the diameters of ovulatory follicles and uterine edema were recorded. After the first ovulation, when the follicle diameters of all mares in both Group A and Group B were analyzed independently of age, and compared between pregnant and non -pregnant mares, no differences were found (P>0.05). The differences between the agerelated groups were insignificant (P>0.05). Follicle diameters between pregnant and non -pregnant mares at the second ovulation were significantly different (P<0.05). It was determined that there was no relationship between age and pregnancy rate (P>0.05). Differences between uterine edema values determined in mares that were pregnant and nonpregnant in two consecutive ovulations were found to be insignificant in terms of pregnancy (P>0.05). As a result, although preovulatory diameter is not a reliable marker for pregnancy detection, it remains an important parameter for determining ovulation and artificial insemination timing. Uterine edema is only useful for determining the timing of insemination and is not associated with pregnancy. Moreover, since similar pregnancy rates were observed among different age groups, age alone is not a sufficient parameter for assessing reproductive efficiency in mares.Öğe The thermographic monitoring in early pregnancy detection in Holstein cows and heifers(Elsevier, 2023) Olgac, Kemal Tuna; Yazlik, Murat Onur; Kaya, Ufuk; Ozkan, Huseyin; Tirpan, Mehmet BorgaThis study aimed to conduct a comprehensive investigation to demonstrate early pregnancy detection using thermography in heifers and cows. A total of 60 heifers (n: 30) and cows (n: 30) were divided into two groups as pregnant (n: 15 heifers, n: 15 cows) and non-pregnant (n: 15 heifers, n: 15 cows) according to the day 28 of gestation. Thermographic images were taken from the vulvar and anal regions on alternate days from D0 to D20. Blood samples were collected to determine estrogen and progesterone concentrations. The mean temperature difference between the anal and vulvar regions (?T C-?) was used in the statistical analyses. Based on the hormonal profiles, no abnormalities were observed for follicular waves or luteal profiles in heifers and cows. The ?T C-? values between heifers and cows and between days were statistically significant (P < 0.001). In thermographic analyses, the differences observed in other main effects and interactions of the group, sampling time, and pregnancy were not statistically significant (P > 0.05). In receiver operating characteristic (ROC) analyses, it was concluded that the ?T C-? value of = 2.9 C-? (100% Se -61.9% Sp) was highly correlated with pregnancy diagnosis in cows on day six after artificial insemination (AI) (P < 0.001). In conclusion, it was determined that the clinical application of thermography can be used for the detection of pregnancy on day six after AI in cows. However, further studies are needed to determine heifers' thermographic characteristics and profiles.Öğe Ultrasonographic patterns of different regions of uterus according to pregnancy in cows and heifers(Wiley, 2023) Olgac, Kemal Tuna; Yazlik, Murat Onur; Kaya, Ufuk; Tirpan, Mehmet BorgaThis study aimed to detect pregnancy within the first 20 days after artificial insemination by evaluating the ultrasonographic patterns of the different regions of uterus in Holstein heifers and cows. Animals were divided into subgroups according to pregnancy on 28th day as pregnant (heifer, n: 15; cow, n: 15) and non-pregnant (heifer, n: 15; cow, n: 15). Images were taken from the ovulation-side cornu uteri (OSC), non-ovulation-side cornu uteri (NOSC), and the corpus uteri (CU) on alternate days from D0 to D20. The images were evaluated by ImageJ software in terms of mean gray value (MGV), homogeneity (HOM), and contrast (CON) and endometrium thickness (ET). The mean MGV and G*T and P*T interactions, the mean CON and G*T and G*P interactions, the mean HOM and G*P interactions, and the mean ET and G*P interactions were statistically significant (p < 0.05). In receiver operating characteristic analyses, D2-D6 for CON and D2, D6, D8, D16, and D20 for HOM of OSC in cows and D8 and D10 MGV and D18 and D20 ET of OSC in heifers had high relationship with positive pregnancy (p < 0.05). The use of echogenicity evaluations and endometrium thickness measurements in reproductive management seems to be suitable for the prediction of pregnancy in cows and heifers.
