Person: GÜMEN, AHMET
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Publication Effect of oestrous expression prior to timed artificial insemination with sexed semen on pregnancy rate in dairy cows(Wiley, 2022-11-16) Güner, Barış; Ertürk, Melih; Dursun, Mehmet; Öztürk, Buse; Yılmazbaş-Mecitoğlu, Gülnaz; Keskin, Abdulkadir; Dikmen, Serdal; Gümen, Ahmet; Yılmazbaş-Mecitoğlu, Gülnaz; KESKİN, ABDULKADİR; DİKMEN, SERDAL; GÜMEN, AHMET; Veteriner Fakültesi; Zootekni Ana Bilim Dalı; 0000-0002-5611-4993; HGP-8282-2022; AAH-3831-2021; A-5731-2018; AAH-1406-2021The objectives of the study were to determine (1) oestrous expression rate and (2) the effect of oestrous expression prior to progesterone-based Ovsynch protocol on pregnancy rate in Holstein cows. All cows (n = 917) were subjected to 7-day progesterone-based Ovsynch protocol. In this protocol, cows that expressed oestrus before (HEAT1) the scheduled second GnRH were inseminated 20 h later after the onset of oestrus without GnRH administration. Cows that expressed oestrus after the second GnRH administration (HEAT2) or did not express oestrus (NOHEAT) received fixed-timed AI. Oestrous expression was determined by using activity-rumination monitoring system and all cows were inseminated with sexed semen. Oestrous expression rate prior to FTAI was 40.5% and the majority (p < .01) of oestrous expression were in HEAT2 compared with HEAT1 in both primiparous (71.8 vs. 28.1%) and multiparous cows (69.5 vs. 30.5%). The mean interval from intravaginal device removal to the onset of oestrus was 47.4 +/- 0.9 h and 62.9 +/- 0.5 in HEAT1 and HEAT2, respectively. Primiparous cows (47.7%) had a higher (p < .01) expression rate compared with multiparous cows (37.2%). Overall pregnancy rate was 37.4% and there was two-way significant interaction between parity and oestrous expression on pregnancy rate (p < .01). Both primiparous (48.1 vs. 35.8%) and multiparous cows (47.4 vs. 28.4%) that expressed oestrus had greater (p < .01) pregnancy rate compared with cows that did not express oestrus. There was no difference in pregnancy rates of HEAT1 and HEAT2 in both primiparous (44.7 vs. 49.5%) and multiparous cows (47.2 vs. 47.6%). Pregnancy rate was not influenced (p = .21) by milk production (high or low) in both primiparous (47.6 vs. 48.6%) and multiparous (54.9 vs. 42.1%) cows that expressed oestrus, respectively. In conclusion, cows showing oestrus before or after second GnRH of the Ovsynch protocol had greater pregnancy rate than cows not showing oestrus.Publication Effects of daily propylene glycol drenching during the Ovsynch protocol on fertility and metabolic parameters in lactating dairy cows(Wiley, 2023-06-18) Çakırcalı, Rabia; Karakaya-Bilen, Ebru; Güner, Barış; Mecitoğlu, Zafer; Ortaç, Cihan Tolga; Keskin, Abdulkadir; Orman, Abdulkadir; Gümen, Ahmet; Çakirçalı, Rabia; MECİTOĞLU, ZAFER; Ortaç, Cihan Tolga; KESKİN, ABDULKADİR; ORMAN, ABDÜLKADİR; GÜMEN, AHMET; Veteriner Fakültesi; Jinekoloji Ana Bilim Dalı; 0000-0001-9138-4422 ; 0000-0002-5557-121X ; DWK-3046-2022; AAH-1677-2021; JLZ-4927-2023; AAH-3831-2021; AAG-9134-2021; AAH-1406-2021Negative energy balance (NEB) caused by restricted feed intake leads to body condition loss (BCS), increased metabolic stress and reduced fertility in dairy cows. Propylene glycol (PG) is a precursor of ruminal propionate for gluconeogenesis used to increase metabolic adaptation to the early postpartum period. The aim of this study was to determine the effects of daily drenching of PG during the fixed-time artificial insemination (FTAI) protocol on beta-hydroxybutyric acid (BHBA), glucose, adiponectin, insulin-like growth factor-1 (IGF1) concentrations, follicle size and pregnancy rate in dairy cows. Cows (n = 148) were randomly divided into two groups and received either 300 mL of PG (PG-OVS, n = 76) or 300 mL of water (CON- -OVS, n = 72) each day of the Ovsynch protocol (GnRH-7 days-PGF2a-56 hours-GnRH-16-18-hour FTAI) between days 57 +/- 3 to 67 +/- 3 postpartum for the first service. Body condition scores (14 days before expected calving, at calving, on days 21 and 42 postpartum) were recorded. Blood samples were collected days 7 +/- 3, 21 +/- 3 postpartum, at the beginning of the Ovsynch (days 57 +/- 3) and at the time of FTAI (days 67 +/- 3) for measurements of BHBA, glucose, adiponectin and IGF1 concentrations. Ultrasonographic examinations were done to measure follicle size at the beginning of Ovsynch and FTAI and to determine pregnancy on days 30 and 60 following FTAI. There were no differences (p >.05) in glucose, adiponectin and IGF1 concentrations between the groups during the study. Although there was no difference ( p >.05) in BHBA concentrations on postpartum day 7 +/- 3, 21 +/- 3 and 57 +/- 3 between the groups, BHBA concentrations at the time of insemination was lower (p <.05) in the PG-OVS group (0.72 +/- 0.03 mmol/L) than in the CON-OVS group (0.81 +/- 0.03 mmol/L). Follicle sizes at the beginning of Ovsynch (PG-OVS, 14.5 +/- 0.48 mm; CON-OVS, 14.3 +/- 0.59 mm) and FTAI (PG-OVS, 17.8 +/- 0.52 mm; CON-OVS, 17.7 +/- 0.42 mm) were not different ( p <.05). Pregnancy rate of the cows in the PG-OVS group (46.1%, 35/76) was higher (p =.05) than in the CON-OVS group (30.6%, 22/72) on day 30 following FTAI. In conclusion, decreasing serum BHBA concentrations at the time of FTAI by means of daily drenching of PG during the Ovsynch protocol, increased the pregnancy rate at first service in lactating dairy cows. On the other hand, blood glucose was not related with pregnancy rates in our study, probably as a result of our sampling time and more rapid fluctuations of blood glucose concentrations when compared to BHBA.Publication The variation in the beta-casein genotypes and its effect on milk yield and genomic values in holstein-friesian cows(Taylor & Francis Inc, 2023-10-12) Aksu, Emrah; Ardıçlı, Sena; ARDIÇLI, SENA; Aldevir, Özgür; Gümen, Ahmet; GÜMEN, AHMET; Veteriner Fakültesi; Jinekoloji ve Doğum Ana Bilim Dalı; 0000-0003-2758-5945; O-3394-2019The A2 milk marker is gaining popularity worldwide; thus, many farms plan to convert their dairy cattle herds to the A2A2 genotype. Variation in beta-casein genotypes needs to be monitored in large dairy cattle populations. Therefore we aimed to evaluate the genotypic distributions, population genetics, and diversity parameters in Holstein-Friesian cows. A total of 1200 cattle were genotyped using the Affymetrix (R) Axiom (R) array system. We performed an association analysis regarding the CSN2 genotypes and phenotypic traits, including lactation and test-day milk yield. We next evaluated the effects of the genotypes considering the genetic merit of the animals. Animals were grouped based on their PTAs for milk production, fat, protein, and daughter pregnancy rate. Thus, we tested the genotype x genetic merit interaction for significance. The A2 allele frequency is remarkably high (0.68), and the heterozygous genotype is predominant (46.25%). The marker showed intermediate variability and diversity levels, indicating a considerable frequency of the A1A1 genotype (9.33%) remains in the population. ANOVA results showed no significant association between the CSN2 genotypes and milk yield traits. A similar finding is valid for the genotype x genetic merit regarding the genomic test results. The data presented here may be helpful for further investigations and applications on A2 milk production.Publication Distributions of CYP19, ERα and PGR allele frequencies between fertile and subfertile Holstein-Friesian heifers(Kafkas Üniversitesi, 2015-11-01) Keskin, Abdulkadir; Öner, Yasemin; Yılmazbaş-Mecitoğlu, Gülnaz; Güner, Barış; Karakaya, Ebru; Elmacı, Cengiz; Gümen, Ahmet; KESKİN, ABDULKADİR; ÖNER, YASEMİN; MECİTOĞLU, GÜLNAZ; Güner, Barış; Karakaya, Ebru; ELMACI, CENGİZ; GÜMEN, AHMET; Ziraat Fakültesi; Hayvan Bilimleri Biyometri ve Genetik Bölümü; 0000-0002-2904-8986; 0000-0003-2817-3221; 0000-0001-6414-6752; 0000-0003-4837-1858; 0000-0003-4819-0221; 0000-0002-3607-4365; V-7882-2019; AIF-3815-2022; ABB-3181-2020; AAH-3831-2021; AAH-1406-2021; AAG-4440-2019; AGY-3496-2022; ABG-2047-2020The aim of this study was to investigate the gene and genotype distributions of some mutations in the aromatase cytochrome P450 (CYP19), estrogen receptor alpha (ER alpha), and progesterone receptor (PGR) genes in fertile and subfertile Holstein-Friesian heifers using the PCR-RFLP method and comparing the distributions between groups. A total of 106 heifers were included the study, and the heifers that became pregnant after the first artificial insemination (n=51) were used as a fertile group. Heifers (n=55) with equal and more than 3 AIs were accepted as a subfertile heifers. Blood samples from all of the heifers were obtained for DNA isolation. While two alleles and three genotypes were found at the PGR and ER alpha loci, two alleles and two genotypes were detected at the CYP19 locus. The A allele and AA genotype, G allele and GG genotype, and C allele and CT genotype were found to be predominant in CYP19, ER alpha and PGR, respectively. According to the chi-square test (chi(2)), two of the groups investigated were in Hardy-Weinberg equilibrium for all gene loci. There were no differences detected in allele or genotype frequencies between the fertile and subfertile heifers.Publication Prolonged gestation in a Swedish Red cow due to fetal unilateral adrenal gland dysgenesis(Tübitak Bilimsel ve Teknolojik Araştırma Kurumu Türkiye, 2019-01-01) Karakaya Bilen, Ebru; Akkoç, Ahmet; Güner, Barış; Yılmazbaş Mecitoğlu, Gülnaz; Gümen, Ahmet; Keskin, Abdulkadir; AKKOÇ, AHMET; Yılmazbaş Mecitoğlu, Gülnaz; GÜMEN, AHMET; KESKİN, ABDULKADİR; Veteriner Fakültesi; Patoloji Ana Bilim Dalı; 0000-0002-5090-7917; 0000-0003-2817-3221; 0000-0002-3607-4365; AAG-4440-2019; AAH-1406-2021; AAH-3831-2021; DTZ-3578-2022A 5-year-old Swedish Red cow, pregnant for 465 days according to the last insemination record, was presented in this case. She conceived by artificial insemination at spontaneous estrus using frozen-thawed sperm of Swedish Red sire. No abnormalities were detected during gestation and no clinical signs of parturition at the expected time of delivery were noted. She was reexamined several times to eliminate breeding records error and, once prolonged gestation was confirmed, parturition was induced. The calf survived birth but died 10 min after birth. A macroscopically giant fetus was diagnosed. Following necropsy, some congenital anomalies were noticed. While the structure of the right adrenal gland was normal, disorganized soft tissue was observed in the left one, in which cortical and medullar regions could not be distinguished. The calf's pituitary gland was also normal. Thus, prolonged gestation was attributed to a case of unilateral adrenal gland dysgenesis.