Sait Sendag

Prof. Dr. Sait Sendag

orcid

Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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17 February 2024 in Reproduction in Domestic Animals
Verified
Journal Article
Open access
DKDavut Koca
Davut Koca
YNYavuz Nak
Yavuz Nak
SSSait Sendag
Sait Sendag
DNDeniz Nak
Deniz Nak
ATAli Osman Turgut
Ali Osman Turgut
AWAxel Wehrend
Axel Wehrend
The anti‐Müllerian hormone (AMH) indicates ovarian reserve in cattle, maintaining a consistent trajectory post‐puberty. In heterosexual pregnancies, the development of the Müllerian duct in female foetuses is inhibited, resulting in an anticipated minimal or absent ovarian reserve capacity. This investigation aimed to compare AMH levels in healthy Holstein heifers that had reached puberty with those of freemartin animals of the same breed and age. The study incorporated Holstein heifers reaching puberty between 11 and 15 months of age in Group 1 (G1, n = 20) and freemartin animals in Group 2 (G2, n = 19, 16). AMH measurements (AMH‐1/AMH‐2) were recorded at 12‐day intervals for the study participants. Notably, AMH levels in three freemartin animals could not be detected, prompting statistical analysis based on measurements from the remaining 16 freemartin animals in G2. A statistically significant correlation was observed between two separate measurements in G1 and G2 (p < .001). Furthermore, AMH‐1 and AMH‐2 levels were statistically higher in G1 than in G2 (p < .001). In G1, AMH‐1 levels ranged from 227 to 677 pg/mL, with an average of 367.3 ± 25.5 pg/mL, and AMH‐2 levels ranged from 234 to 645 pg/mL, with an average of 380.8 ± 24.4 pg/mL. Conversely, in G2, AMH‐1 levels ranged from 10 to 72 pg/mL, with an average of 26.8 ± 4.44 pg/mL, and AMH‐2 levels ranged from 12 to 68 pg/mL, with an average of 28.75 ± 4.18 pg/mL. The mean AMH levels in G1 were approximately 14 times higher than in G2 (p < .001). Consequently, ROC analysis utilizing AMH‐1 and AMH‐2 data established cut‐off values of ≤72 and ≤ 68 pg/mL respectively for distinguishing freemartin animals. In conclusion, AMH could be used as a reliable biomarker for identifying Holstein freemartin animals.

3 October 2023 in Reproduction in Domestic Animals
Verified
Journal Article
Open access
DKDavut Koca
Davut Koca
YNYavuz Nak
Yavuz Nak
SSSait Sendag
Sait Sendag
DNDeniz Nak
Deniz Nak
TATalha Avcılar
Talha Avcılar
AWAxel Wehrend
Axel Wehrend
Anti‐Müllerian hormone (AMH) levels in the blood of dairy cattle are associated with the count of antral follicles (AFC), ovarian function. Numerous studies, particularly in human medicine, have shown that vitamin D3 (Vit D3) has a positive effect on AMH levels. To our knowledge, the effects of Vit D3 on serum AMH levels in heifers have not been investigated. The goal of the current study was to evaluate the concentrations of serum AMH in dairy heifers following Vit D3 treatment. The study included 20 healthy non‐pregnant Holstein Friesian heifers. These animals came to estrus at least once. All heifers received a single intramuscular dosage of 5 million IU Vit D3 (Cholecalciferol). Blood samples were collected from the coccygeal veins of all animals before and after Vit D3 injection (days 7, 14, and 28) for the measurement of AMH and 25(OH)D concentrations. In our analysis, we observed that after exogenous Vit D3 administration, circular 25(OH)D increased constantly (up to day 28 after Vit D3 injection) in all animals. On day 28, AMH concentrations saw a 10% increase in comparison with those measured the day before the Vit D3 injection. However, a comparison of AMH concentrations measured across days did not reveal statistically significant differences between Day 0, 7, 14, and 28 levels (p = .10). Furthermore, no statistical correlation was observed between the pairs (age‐AMH) and (weight‐AMH). Considering all times, no correlation was found between 25(OH)D and blood AMH levels. These findings demonstrated that exogenous Vit D3 did not affect serum AMH in Holstein Friesian heifers.


19 June 2023 in Veterinary Medicine and Science
Verified
Journal Article
Open access
SSSait Sendag
Sait Sendag
MSMarlene Sickinger
Marlene Sickinger
TATalha Arslan
Talha Arslan
GSGerhard Schuler
Gerhard Schuler
AWAxel Wehrend
Axel Wehrend
Objective: The current study investigates how uterine torsion influences placental oestrogens and progesterone blood concentrations in intrapartum cows. Our research tests the hypothesis that intrapartum uterine torsion impairs the ability of the placenta to synthesize steroids and may also suppress the release of synthesized steroids into the maternal circulation.Methods: The study included a total number of 37 intrapartum dairy cows of various breeds and ages. These animals were transported to our clinic by their owners. Furthermore, general and obstetrical examinations of all these animals were performed in our clinic. The uterine torsion (UT) group consisted of 20 animals. The presence of UT was verified during clinical general examinations by vaginal and transrectal examination. The comparison (C) group included 17 animals whose birth was undisturbed or could be terminated with moderate obstetrical assistance. The clinical examination of group C animals showed no problems with their general health and genital organs. Blood samples were collected immediately after the initial obstetrical examination from 37 cows for radioimmunological measurement of estradiol‐17β (E2), free total estrogen (FTE), conjugated total estrogen (CTE), and progesterone (P4).Results: In terms of P4, there was no statistical difference between the two groups. For all estrogen parameters, however, concentrations were significantly lower in the UT group than in the C group. In the correlation analysis, there was a significant correlation between the P4 and the FTE in the C group. Furthermore, the positive correlation between all estrogen parameters in the UT group was significant. In group C, significant positive correlations were found apart from the correlation between E2 and CTE.Conclusions: The results are consistent with the hypothesis and suggest that in UT animals processes dependent on estrogens or other placental hormones may be impaired during the peri‐ or postpartum period.

15 February 2025 in Journal of Feline Medicine and Surgery
Verified
Journal Article
Open access
SSSait Sendag
Sait Sendag
DHDoreen Hardegen
Doreen Hardegen
DKDavut Koca
Davut Koca
AWAxel Wehrend
Axel Wehrend
Objectives: The aim of this study was to investigate the efficacy and success of emergency obstetric care interventions for feline dystocia and to analyse the effects of therapeutic interventions on maternal mortality and stillbirth. Methods: This retrospective, observational study included 153 queens of various breeds and ages that presented to the clinic with dystocia. Anamnesis, signalment, physical examination, ultrasonography, radiography and subsequent intervention data were also collected. Differences in stillbirth rates between the treatment groups were evaluated using the χ2 test. The mean litter size, mean duration of labour and number of stillbirths were calculated in each case. In addition, to obtain information on further breeding of dystocia patients, 51 queen owners were contacted by telephone. Results: Medical treatment was successful in 17% of patients, and 83% underwent surgical treatment for dystocia. Ovariohysterectomy (59%) was the most common surgical method, followed by conservative caesarean section (35%). En bloc resection was performed in 6% of patients. A total of four (2.4%) queens died. Of 542 kittens from 153 deliveries, 210 (39%) were stillborn. Singleton pregnancies were associated with a high risk of difficult labour. Similarly, prolonged duration of labour increased the stillbirth rate. The fertility status of queens after caesarean section was assessed by interviewing 51 owners, 27 (53%) of whom provided information. Of these, 12 were mated again and nine successfully (they became pregnant with successful natural births in five). Conclusions and relevance: Similar to previous studies, our data showed that medical management led to success in only a minority of cases. In addition, mortality data for emergency births under modern standardised treatment conditions were provided. Singleton pregnancy is a suspected risk factor for dystocia. Pregnancy after caesarean section is possible with natural unassisted birth.

1 February 2014 in Theriogenology
Verified
Journal Article
Closed access
YCYunus Cetin
Yunus Cetin
MKMesih Kocamuftuoglu
Mesih Kocamuftuoglu
NONihat Ozyurtlu
Nihat Ozyurtlu
IKIbrahim Kucukaslan
Ibrahim Kucukaslan
SSSait Sendag
Sait Sendag
AWAxel Wehrend
Axel Wehrend