Browsing by Author "Koca, Davut"

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Anti-Mullerian Hormone as a Promising Novel Biomarker for Litter Size in Romanov Sheep
(Wiley, 2024) Turgut, Ali Osman; Koca, Davut
Anti-Mullerian hormone (AMH) is a hormone produced by growing preantral and antral follicles of the ovary. AMH is accepted as an important biomarker for fertility and superovulation parameters in livestock species. This study aimed to evaluate changes in serum AMH level in the oestrous cycle, repeatability of AMH, the effect of age on serum AMH level and the effects of AMH on litter size in Romanov sheep. In the study, a total of 36 Romanov sheep were used as animal material. First blood samples (0th day) were collected from 36 ewes to evaluate AMH and progesterone levels. Second blood samples were collected randomly from 20 ewes 9 days after first sampling to compare AMH levels at two different periods of the oestrous cycle in Romanov ewes. The ewes were categorized into three groups as low, medium and high AMH based on their first AMH levels. Results indicated that serum AMH level did not change during the oestrous and dioestrous phases of the oestrous cycle and two random time points of the oestrous cycle (p > .05). Pearson correlation analysis revealed that there is a high (r = .95) and significant (p < .001) correlation between AMH levels at the 0th (AMH-1) and 9th (AMH-2) days. The effect of AMH level on litter size was found to be significant. Litter size was significantly higher in the high AMH group than in the low AMH group (p < .05). In addition, the age of ewes did not affect serum AMH levels (p > .05). ROC analysis indicates that AMH cut-off value >320 pg/mL with 70% sensitivity and 100% specificity can be used for litter size in Romanov ewes. In conclusion, AMH is highly repeatable and its serum AMH level did not change during the oestrous cycle in Romanov sheep. In addition, AMH affects litter size and can be reliably used as a marker for litter size in Romanov sheep.
Anti-Mullerian Hormone Concentrations Can Be Reliably Determined by a Single Measurement, Irrespective of Cycle, in Synchronised Ewes During Non-Breeding Season
(Wiley, 2025) Cetin, Nebi; Koca, Davut
Improvement of yield characteristics in animal breeding is important in terms of increasing animal production and sustainability. Fertility is one of the most important yield traits affecting economic gain in sheep breeding. Anti-M & uuml;llerian Hormone (AMH) is widely recognised as a dependable biomarker for assessing ovarian reserves and fertility potential. The aim of this study was to evaluate the dynamics of AMH during different phases of the sexual cycle in Norduz ewes the non-breeding season. Additionally, the study sought to assess the effects of age and body condition score (BCS) on AMH concentrations during these phases. A total of 32 Norduz ewes with a body condition score (BCS) of 3-4.5 and aged between 2 and 4 years were used as animal material in the study. All experimental procedures were carried out outside the breeding season and when the ewes were lactating. In all ewes in anestrus, intravaginal sponges (Esponjavet, 60 mg MAP, Hipra, Turkey) were kept in the vagina for 7 days for estrus synchronisation. Intramuscular injections of PMSG (Oviser, 500 IU, Hipra, Turkey) and PGF2 alpha analog (Gestavet, 50 mu g, Hipra, Turkey) were administered 48 h prior to sponge removal. Twenty-four hours after sponge removal, ewes were exposed to the ram for estrus detection. Since 5 ewes did not show estrus, blood samples were collected regularly from animals (n = 27) in which estrus was detected at three different stages: one just before the insertion of vaginal sponges (anestrus), another when heat was detected exposing to the ram (estrus), and the final one 10 days after estrus (diestrus). The serum samples were assessed for the levels of AMH and progesterone through the electrochemiluminessence immunoassay technique (ECLIA). The results of the analyses showed that serum AMH concentration did not vary between anestrus, estrus and diestrus phases of the sexual cycle of Norduz ewes outside the breeding season (p > 0.05). Furthermore, age and BCS had no effect on progesterone and AMH levels in different phases of the sexual cycle (p > 0.05). In conclusion, this study shows that serum AMH levels are constant at any stage of the estrus cycle. This suggests that phenotypic evaluation of ewes can be performed with a single measurement and that AMH is a reproducible and dependable biomarker that can be measured at any stage of the estrus cycle at an arbitrary time point.
Anti-Müllerian Hormone: a Novel Biomarker for Detecting Bovine Freemartinism
(Wiley, 2024) Koca, Davut; Nak, Yavuz; Sendag, Sait; Nak, Deniz; Turgut, Ali Osman; Avcilar, Talha; Wehrend, Axel
The anti-M & uuml;llerian hormone (AMH) indicates ovarian reserve in cattle, maintaining a consistent trajectory post-puberty. In heterosexual pregnancies, the development of the M & uuml;llerian 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.
Comparison of Blood Βhba Measurement Devices for Diagnosis of Subclinical Pregnancy Toxaemia in Sheep: a Field Study
(Wiley, 2024) Turgut, Ali Osman; Koca, Davut; Unver, Ali
Pregnancy toxaemia is a serious disease that occurs during the last trimester of pregnancy in sheep. Yet, in most cases, the disease may have a subclinical course. This study was aimed at comparing blood beta HBA measurement devices for diagnosis of subclinical pregnancy toxaemia in late pregnant sheep. In the study, a total of 50 blood samples were collected from Romanov (n = 30) and cross-bred Hamdani (n = 20) sheep. Blood beta HBA levels were measured using TaiDoc TD-4235 and CentriVet beta HBA hand-held meter. Randox beta HBA (Ranbut) assay was used as a reference laboratory method to compare hand-held meters. beta HBA value of 0.8 mmol/L was set as the cut-off value for diagnosis of subclinical pregnancy toxaemia. Statistical analyses were carried out using Minitab 21 and Jamovi software. In the study, the correlation of Randox-TaiDoc TD-4235 and Randox-CentriVet was .822 (p < .001) and .728 (p < .001), respectively. Based on the Ranbut assay, nine ewes out of 50 were diagnosed with subclinical pregnancy toxaemia. Specificity (detection of healthy ewes) and sensitivity (detection of ewes with subclinical pregnancy toxaemia) for TaiDoc TD-4235 and CentriVet hand-held meters were 100%, 77.8%, and 100%, 66.7%, respectively. In the receiver operating characteristic (ROC) analysis, areas under the ROC curve (AUC) were 0.976 and 0.920 for TaiDoc and CentriVet, respectively. Bland-Altman analysis revealed a bias of 0.092 mmol/L for TaiDoc and a bias of 0.132 mmol/L for CentriVet. TaiDoc hand-held meter shows a better correlation with the Randox Ranbut assay and greater sensitivity compared to the CentriVet hand-held meter. In conclusion, both TaiDoc and CentriVet hand-held meters can be securely used in the diagnosis of subclinical pregnancy toxaemia in sheep. For these reasons, subclinical pregnancy toxaemia and these devices will be evaluated within the scope of herd management programme in the sheep industry. It should also be taken into account that these conditions will affect the future fertility of the mother and offspring.
Comprehensive Evaluation of Changes in Placentomes in the Second and Third Trimesters of Pregnancy in Cross-Bred Hamdani Sheep
(Wiley, 2025) Kandil, Banu; Turgut, Ali Osman; Koca, Davut; Isbilir, Fatma; Atli, Muhammed Zahid; Guzel, Baris Can
Background: A proper placentation is required for establishment and continuity of pregnancy. In sheep, placentomes are unique structures that enable nutrition and gas exchange between the mother and the foetus. Although placentomes are dynamic formations, there is limited knowledge of changes in placentomes during pregnancy. Objective: This study aimed to identify changes in sheep placentomes in the second and third trimesters of pregnancy using both macroscopic and microscopic methods. Methods: This study investigated 14 healthy cross-breed Hamdani sheep placentomes, comprising seven second and seven third trimesters of pregnancy. The histomorphometric analysis included measurements of capillary number and area in cotyledonary and caruncular regions, while morphometric assessments encompassed placentome dimensions such as number, length, width, and depth. Results: Placentomes were oval and circular in shape in the second and third trimesters. In the second trimester, they were observed as concave structures with thick edges, whereas in the third trimester, they were determined as thin-edged structures with a slight depression in the centre. In the third trimester, foetal and maternal tissues became more intertwined with increased branching of foetal villi and maternal crypts. Placental hematomas and erythrocytes in the cytoplasm of trophoblast cells were more prominent in the third trimester. Statistical analysis revealed no difference in placentome number between the second and third trimesters. However, the dimensions (length, width, and depth) of placentomes were greater in the third trimester compared to the second trimester (p < 0.001). Additionally, while there was no difference in the number of cotyledonary versus caruncular capillaries in the second trimester, cotyledonary capillaries outnumbered caruncular capillaries in the third trimester (p < 0.001). Furthermore, both cotyledonary and caruncular capillary areas increased in the third trimester compared to the second trimester, with the caruncular capillary area being consistently higher than the cotyledonary capillary area in both trimesters (p < 0.05). Conclusion: This study underscores the substantial structural and physiological transformations of placentomes in the second and third trimesters of pregnancy in sheep. These adaptations facilitate efficient flow exchange between the foetus and mother, highlighting the dynamic nature of placental development during late gestation.
The Effects of Case/Control Ratio and Sample Size on Genome-Wide Association Studies: a Simulation Study
(Wiley, 2024) Turgut, Ali Osman; Koca, Davut
BackgroundGenome-wide association studies (GWAS) is a useful tool for the detection of disease or quantitative trait-related genetic variations in the veterinary field. For a binary trait, a case/control experiment is designed in GWAS. However, there is limited information on the optimal case/control and sample size in GWAS.ObjectivesIn this study, it was aimed to detect the effects of case/control ratio and sample size for GWAS using computer simulation under certain assumptions.MethodUsing the PLINK software, we simulated three different disease scenarios. In scenario 1, we simulated 10 different case/control ratios with increasing ratio of cases to controls. In scenario 2, we did versa of scenario 1 with the increasing ratio of controls to cases. In scenarios 1 and 2, sample size gradually was increased with the change case/control ratios. In scenario 3, the total sample size was fixed to 2000 to see real effects of case/control ratio on the number of disease-related single nucleotide polymorphisms (SNPs).ResultsThe results showed that the number of disease-related SNPs were the highest when the case/control ratio is close to 1:1 in scenarios 1 and 2 and did not change with an increase in sample size. Similarly, the number of disease-related SNPs was the highest in case/control ratios 1:1 in scenario 3. However, unbalanced case/control ratio caused the detection of lower number of disease-related SNPs in scenario 3. The estimated average power of SNPs was highest when case/control ratio is 1:1 in all scenarios.ConclusionsAll findings led to the conclusion that an increase in sample size may enhance the statistical power of GWAS when the number of cases is small. In addition, case/control ratio 1:1 may be the optimal ratio for GWAS. These findings may be valuable not only for veterinary field but also for human clinical experiments. An increase in sample size may enhance the statistical power of GWAS when the number of cases is small. Case/control ratio 1:1 may be the optimal ratio for GWAS. These findings may be valuable not only for veterinary field but also for human clinical experiments. image
The Effects of Supplementation of Vitamin D To the Egg-Yolk Extender on Cryopreservation of Ram Semen
(Wiley, 2024) Aktar, Ahmet; Toker, Mehmed Berk; Koca, Davut; Uzun, Umit Can; Alcay, Selim
Objectives: This study aimed to examine the effects of supplementation of vitamin D to the egg-yolk extender on characteristics of frozen-thawed ram semen. Methods: Semen samples obtained from adult rams were pooled and divided into five equal volumes. It was reconstituted with extenders containing different concentrations of vitamin D: 0 (control), 12.5 (VITD 12.5), 25 (VITD 25), 50 (VITD 50), and 100 ng/mL (VITD 100), and then they were frozen. Sperm motility parameters, plasma membrane functional integrity, acrosomal integrity, DNA fragmentation, and mitochondrial membrane potential of the groups were evaluated after sperm thawing. Results: Total motility and progressive motility were higher in VITD 50 than in all other groups (p < 0.05). Higher sperm straightness, linearity, and wooble were higher in VITD 50 than in the control group (p < 0.05). A similar pattern of VITD 50 was observed for plasma membrane integrity and mitochondrial membrane potential (p > 0.05). Conclusions: In the study, it was observed that adding vitamin D to the extender had a beneficial effect on ram spermatological parameters. In addition, it was concluded that the use of the 50 ng/mL vitamin D in the extender provided more effective protection than the other doses.
Elecsys® Amh Assay: Determination of Anti-Müllerian Hormone Levels and Evaluation of the Relationship Between Superovulation Response in Holstein Dairy Cows
(Wiley, 2024) Koca, Davut; Aktar, Ahmet; Turgut, Ali Osman; Sagirkaya, Hakan; Alcay, Selim
Background: Anti-Mullerian Hormone (AMH) serves as a crucial parameter in assessing the reproductive herd life and ovarian reserve in cattle. Consequently, extensive research is conducted on AMH levels. Various measurement methods can be employed to determine AMH levels. However, to our knowledge, no study has been conducted on Holstein donors using the Elecsys (R) AMH kit. Objective: This study was designed to determine AMH levels in donors utilising the Elecsys (R) AMH kit and to evaluate the relationship between superovulation response parameters and AMH levels. Methods In this study, we measured the serum AMH levels of 36 cows using the Elecsys (R) AMH automated assay before the superovulation protocol (1st sample) and FSH injections (2nd sample). The cows were categorised into three groups based on their AMH levels: low, medium, and high AMH. Results: Positive correlations were identified between AMH and parameters associated with superovulation response. The high AMH level group exhibited significantly greater numbers of corpus luteum, total embryos, transferable embryos, and grade 1 embryos compared to the medium and low AMH groups (p < 0.05) There was no significant difference between AMH levels before the superovulation protocol and FSH injections(p > 0.05). Body condition score and parity did not significantly affect AMH levels in cows (p > 0.05). Also, AMH cut-off values for the number of corpus luteum, total embryo, and transferable embryos were detected as 234, 227, and 210 pg/mL, respectively. Conclusion: These findings demonstrate that a high serum AMH level has a positive influence on the superovulation response. AMH can be used as a reliable marker for the selection of donors in Holstein cows.
Evaluation of Placentome Morphology in the Last Two Periods of Pregnancy in Hair Goats (Capra Aegagrus Hircus)
(Wiley, 2024) Isbilir, Fatma; Kandil, Banu; Isbilir, Ihsan; Koca, Davut; Guzel, Baris Can
This study was carried out on pregnant uteruses obtained from healthy Hair goats (Capra aegagrus hircus). A total of thirteen pregnant uteruses, six second and seven third trimesters, were used. Morphometrically, placentome numbers, lengths, widths and depths were measured. Randomly selected placentomes from the second and third trimesters were stained with the triple staining method. Caruncular and cotyledonary areas, capillary numbers and areas were measured using Qupath v0.5.0 software. The Minitab (version 21.4.1) was used for statistical analysis. While no statistical difference was observed in the number of placentomes between trimesters (p > 0.05), placentome length, width and depth were higher in the third trimester compared to the second trimester (p < 0.001). No difference was observed in the number of caruncular and cotyledonary capillaries in the second trimester. In the second trimester, the caruncular capillary area was higher than the cotyledonary capillary area (p < 0.05). Both caruncular and cotyledonary capillary area parameters were higher in the third trimester than in the second trimester (p < 0.001). In the third trimester, the caruncular capillary area was higher than the cotyledonary capillary area (p < 0.001). The number of caruncular capillaries and cotyledonary capillaries was statistically significantly higher in the third trimester compared to the second trimester. In addition, the number of cotyledonary capillaries was higher than that of caruncular capillaries in the third trimester (p < 0.001). A positive and significant correlation was found between the day of pregnancy and the number of placentomes in the second trimester (p < 0.05). No correlation was observed between the day of pregnancy and the number of placentomes in the third trimester. Vascular area density showed a faster development in foetal tissue than in maternal tissue. Placentome size and angiogenesis increased with the progression of pregnancy.
Evaluation of Serum Anti-Mullerian Hormone Concentrations Following Treatment With Vitamin D in Holstein Friesian Heifers
(Wiley, 2023) Koca, Davut; Nak, Yavuz; Sendag, Sait; Nak, Deniz; Avcilar, Talha; Sahin, Mustafa Eren; Wehrend, Axel
Anti-Mullerian 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.
Evaluation of Some Systemic Inflammatory Biomarkers in Canine Malignant Mammary Tumors [I]
(Kafkas Univ, veteriner Fakultesi dergisi, 2023) Ekici, Zeynep Merve; Ozyigit, Musa Ozgur; Nak, Deniz; Avci Kupeli, Zehra; Kuruoglu, Fikriye Ecem; Koca, Davut; Nak, Yavuz
The aim of this study is to investigate whether neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), albumin-to-globulin ratio (AGR), and prognostic nutritional index (PNI) parameters could be used as biomarkers for canine malignant mammary tumors (MMTs), and the changes in these parameters according to different tumor (T), lymph node (N), and metastasis (M) stages (TNM I-II-III, TNM IV, TNM V) and the number of affected mammary glands (single, multiple). Thirty-seven with MMT and 20 healthy dogs were used in this study. Complete blood count and biochemistry analysis were performed in all dogs. Tumor material is removed by tru-cut and sent to the pathology laboratory for diagnosis. NLR, PLR, and SII values increased, and LMR and PNI values decreased in dogs with MMT. Median NLR values increased and median LMR and PNI values decreased as the TNM stage progressed. In dogs with a single MMT, median NLR, and PLR values were found to be lower than in dogs with multiple MMTs, and median LMR, SII, AGR, and PNI values were higher. The present results indicated that NLR, LMR, PLR, SII, and PNI parameters could be used as biomarkers for canine MMT. Also, NLR, LMR, PLR, SII, PNI, and AGR parameters may be valuable biomarkers that reveal the degree of systemic immune response according to different TNM stages and the number of affected mammary glands.
Incidence of Some Reproductive Problems Following a Voluntary Waiting Period in Cows on Family-Type Cattle Breeding Farms in Van Province
(2024) Çetin, Nebi; Koca, Davut
This study aimed to identify some reproductive problems in cows on family-type cattle breeding farms in rural areas of Van province using transrectal ultrasonographic examination. The study included 196 cows (at least 50 days postpartum and non-pregnant) of various breeds and ages. Postpartum days and current body condition scores (BCS) were recorded. Genital organs of each animal were examined twice using rectal palpation and ultrasonography, at intervals of 7-11 days. Cows with a detected corpus luteum in their ovaries were classified as cyclic, while those without were classified as non-cyclic, also categorized according to anovulatory anestrus types. The average number of days postpartum for cows was determined to be 94.42 days. Based on ovarian examination results, 51.03% (n = 99) of the cows were classified as cyclic, while 48.97% (n = 95) were classified as non-cyclic. According to anovulatory anestrus types, 15% (n = 15) of the cows were classified as Type I anovulatory anestrus, 26% (n = 26) as Type II anovulatory anestrus, 54% (n = 54) as Type III anovulatory anestrus, and 5% (n = 5) as Type IV anovulatory anestrus. In addition, pyometra was diagnosed in two of the cows. In the study, it was concluded that the cows in family-type cattle breeding farms in rural areas of Van Province were delayed in starting postpartum cycle activities and high anestrus rates may be primarily due to nutrition. It was concluded that the widespread use of ultrasonography in family-type cattle breeding farms would have significant and positive effects on the reproductive success of cows and sustainable animal breeding.
Investigation of Maternal Mortality and Stillbirth in Feline Dystocia After Emergency Obstetric Care Interventions: a Retrospective Analysis
(Sage Publications Ltd, 2025) Sendag, Sait; Hardegen, Doreen; Koca, Davut; Wehrend, Axel
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 chi 2 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.
Investigation of Relationships Between Serum Lactate, Acute Phase Proteins, Pro/Antiinflammatory Cytokine Levels, and Metritis Formation in Holstein Dairy Heifers
(Tubitak Scientific & Technological Research Council Turkey, 2023) Avcilar, Talha; Koca, Davut; Nak, Yavuz; Sahin, Mustafa Eren; Ozyigit, Musa Ozgur; Nak, Deniz
The main purpose of this investigation was to identify and suggest suitable early screening inflammatory markers for the early diagnosis of uterine infections such as acute septic metritis (ASM) in the Holstein heifers. In addition, to achieve the above-mentioned aim, the objectives of the present study were tried to determine the relationship between blood serum lactate, acute phase proteins (APPs), pro/anti inflammatory cytokine levels, and metritis formation in Holstein heifers. For this purpose, 250 Holstein heifers which were 11-13 months old, were chosen as the study material. After heifers were conceived, blood serum samples were collected at the 8th and 4th weeks before the parturition. In the postpartum period, animals with ASM (n = 15) and healthy animals (n = 15) were identified, and blood serum samples were taken. Lactate, serum amyloid-A (SAA), haptoglobin (Hp), Interleukin-1beta (IL-1 (3), IL-6, IL-8, IL-10, and tumor necrosis factor-alpha (TNF -& alpha;) levels were measured from these collected blood serum samples. Acute-phase proteins, lactate, and pro and anti inflammatory cytokine levels of healthy and animals with ASM were statistically compared. Heifers with metritis had a significantly greater concentration of IL-6 and SAA versus healthy heifers in the prepartum 8th week. In addition, it was determined that IL-6, IL-1(3, IL-10, TNF-& alpha;, and SAA levels were significantly higher in the 4th week before parturition in the ASM group than those of the healthy group. When all these findings are evaluated together, this study suggested that IL-6, and IL-10, can be used as early biomarkers in the prepartum preliminary diagnosis of postpartum important inflammatory processes such as ASM.
Melatonin Receptor 1a (Mtnr1a) Gene Polymorphism in Cross-Bred Hamdani Sheep: a Preliminary Study
(2024) Turgut, Ali Osman; Koca, Davut
Melatonin plays a key role in regulating several vital physiological processes, including the maturation and functioning of the reproductive system, pubertal development, seasonal reproduction, and adaptation. The activation of the melatonin hormone is facilitated by melatonin receptors. This study aimed to investigate melatonin receptor 1A (MTNR1A) gene polymorphism in cross-bred Hamdani sheep. A total of 102 cross-bred Hamdani ewes were used as animal material. DNA was extracted from whole blood. The 824 bp PCR products from the exon II region of the MTNR1A gene underwent analysis for restriction fragment length polymorphism (RFLP) using the RsaI restriction enzyme. In the study, RR, Rr, and rr genotypes were detected for MTNR1A gene in cross-bred Hamdani sheep. Genotype frequencies for RR, Rr, rr were 0.69, 0.27, and 0.04, respectively. Allele frequencies were detected as 0.82 and 0.18 for R and r alleles, respectively. In conclusion, more comprehensive research investigating association between MTNR1A genotypes and reproductive traits should be carried out in cross-bred Hamdani sheep.
Methods for Evaluating Testicular Function in Domestic Cats
(Wiley, 2025) Homola, Stepanka; Sendag, Sait; Koca, Davut; Wehrend, Axel
This study aimed to describe the physiological sonomorphology of the cat testicle and to verify the findings by histological and endocrinological analyses. Furthermore, two methods of testicle measurement and volume calculation were compared. For the study, a clinical examination of the testicles was carried out in 39 cats. The testicles were measured with the Podany testimeter and using a sonographic examination. This was followed by a castration and histological examination of the testicle. The testosterone level was measured from a blood sample. The cat testicles showed a characteristic sonomorphology. The parenchyma was homogeneous, with a distinct echogenic mediastinum. The histological examination verified that there was spermatogenesis activity in testicular tissue. It was found that the testosterone concentrations varied greatly between the animals (0.1-4.40 ng/mL) although spermatogenesis was detected in all cats. Significant correlations were detected between right and left testicular volumes of the cats according to the measured values of sonography and Podany testimeter (p < 0.001). In addition, there was a significant and positive correlation between testosterone and testicular volume. Testosterone levels increase with increasing testicular volume according to the sonographic method (p < 0.05). With the help of the sonographic measurement, significantly higher testicular volumes are calculated than were compared with the measurement method with the Podany testimeter (p < 0.05). The present study is the first to provide detailed information and reliable data for the evaluation of the testicle size and volume in male cats as well as for sonomorphology, which can be used as comparison values for the andrological examination of this animal species.
Milk Composition Traits of Hamdani Crossbreed Sheep Raised Under Extensive Management
(2023) Turgut, Ali Osman; Gülendağ, Erman; Koca, Davut; Üner, Sefa
This study aimed to reveal the milk composition traits of Hamdani crossbred sheep (Hcs) raised under extensive conditions. A total of 96 sheep milk samples were collected during the early lactation stage. Selected ewes did not have clinical mastitis or subclinical mastitis. Milk composition analyses were performed using milk autoanalyzer. Mean values for milk fat (%), solid non-fat (SNF) (%), protein (%), lactose (%), salt (%) and pH, conductivity (mS/cm), freezing point (⸰C) and density (kg/m3) in Hcs were determined as 7.49±0.15, 8.69±0.08, 4.13±0.04, 3.89±0.04, 0.62±0.01, 6.93±0.04, 4.05±0.07, -0.5±0.01, and 1.027.84±0.38 respectively. In correlation analysis, negative and significant correlations were detected between milk fat and protein (r=- 0.368, p<0.001), milk fat and SNF (r=-0375, p<0.001) milk fat and lactose (r=-0.380, p<0.001). On the other hand, positive and significant correlations were detected between SNF and milk protein (r=0.999, p<0.001), SNF and salt (r=0.963, p<0.001), and SNF and lactose (r=0.976, p<0.001). As a result, the milk fat percentage of Hcs was higher compared to other native sheep breeds of Turkey. In addition, phenotypic variation for milk fat percentage was found to be high among individuals in the same flock. These findings may contribute to new studies to improve milk composition traits in Hamdani crossbred sheep.
Molecular Survey of the Toxoplasma Gondii and Neospora Caninum in Brain Tissue of Aborted Fetuses of Morkaraman Sheep in Muş, Türkiye
(2023) Turgut, Ali Osman; Koca, Davut; Celık, Burcak Aslan; Ayan, Özge Oktay; Çelik, Özgür Yaşar; Ayan, Adnan; Kılınç, Özlem Orunç
Toxoplasma gondii and Neospora caninum are obligate intracellular protozoan parasites that can affect different warm-blooded species worldwide. In this study, it was aimed to detect T. gondii and N. caninum using PCR method in brain tissues of aborted sheep fetuses. Brain specimens were collected from 50 Morkaraman sheep fetuses that had undergone abortion at various stages of pregnancy, within the lambing seasons of 2023 in Muş. Approximately 1 cm³ of brain tissue from the right cerebral hemisphere was excised and subsequently frozen at -20°C for DNA extraction. DNA extraction and PCR amplification were then performed. As a result of this study, 11 (22%) of 50 brain tissues were positive. All brain samples examined in this study were negative for Neospora caninum. Based on the results of this study, it is possible to say that T. gondii is an important abortion agent in sheep in this region. Although N. caninum was not detected in this study, larger scale studies are recommended. Moreover, this study provides important information to breeders and veterinarians in the evaluation and management of abortion in the field.
Molecular Survey of Toxoplasma Gondii Infection in Aborted Fetuses of Sheep in the Iğdır Province of Türkiye
(2023) Koca, Davut; Kılınç, Özlem Orunç; Ayan, Adnan; Oğuz, Fatma Ertaş; Turgut, Ali Osman; Ayan, Özge Oktay
Toxoplasma gondii, an obligatory intracellular protozoan parasite, can infect a wide range of warm- blooded animals, including livestock species. T. gondii is a zoonotic protozoan parasite that affects both humans and other warm-blooded animals. The aim of this study was to detect T. gondii by using PCR in the brain tissues of 60 aborted sheep fetuses from the Iğdır Province in Türkiye. For this purpose, 60 brain tissue samples of sheep were collected within the lambing seasons of 2023 in Iğdır, Türkiye. The DNA extraction was performed using the PureLink™ Genomic DNA Mini Kit from brain samples. The PCR was performed with the appropriate primers from the obtained DNA samples. T. gondii was found in the brain (16.6%) samples of aborted sheep fetuses. According to the present study, T. gondii infection can be one of the causes of fetus abortion of sheep in Iğdır province, Türkiye. This result emphasizes the need for vigilance and preventive measures in managing this potential public and animal health concerns.
The Negative Effects of Subclinical Pregnancy Toxaemia on Fetal Skeletal Muscle Development and Evaluation of the Protective Effects of Dietary L-Carnitine Supplementation in Sheep
(Wiley, 2025) Turgut, Ali Osman; Kandil, Banu; Bilen, Ebru Karakaya; Koca, Davut; Unver, Ali; Isbilir, Fatma; Wehrend, Axel
This study evaluated the effects of subclinical pregnancy toxaemia (SPT) on fetal skeletal muscle development and assessed the potential protective role of L-carnitine supplementation during gestation. A total of 18 crossbred Hamdani ewes underwent oestrous synchronisation, natural mating and pregnancy confirmation via ultrasonography on day 45 post-mating. The ewes were managed according to NRC (2007) dietary guidelines until day 100 of gestation, after which they were assigned to three experimental groups: subclinical PT group (group 1; G1, n = 6), treatment group (subclinical PT + L-carnitine, group 2; G2, n = 6) and control group (group 3; G3, n = 6). Blood beta-hydroxybutyrate (beta HBA) concentrations were measured on day 100 and 138 of the gestation. Then, all ewes were slaughtered for fetal muscle sampling from the Musculus Longissimus Dorsi (MLD) and Vastus Lateralis (VL). Results indicated a significant reduction in muscle fibre number and fibre diameter in both MLD and VL in the SPT group (G1) compared to the control (G3) (p < 0.05). No significant differences were observed between G1 and G2 or between G2 and G3 for these parameters (p > 0.05). On the other hand, large effect sizes for group and pairwise comparisons imply that SPT may negatively affect prenatal muscle development and L-carnitine supports muscle development during the prepartum period. These findings highlight the negative effects of SPT and protective effects of L-carnitine supplementation on fetal skeletal muscle development in ewes with SPT. The observed deficits may negatively impact postnatal growth, survival rates and meat quality. Further investigations are warranted to optimise maternal nutrition strategies and evaluate therapeutic interventions aimed at mitigating the adverse impacts of SPT on fetal muscle development in ruminants. Furthermore, L-carnitine supplementation may be a useful in compensating for the negative effects of SPT.