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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.
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    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; Ekici, Zeynep Merve
    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.
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    Chemical Composition and Physical Properties of Milk in Norduz Sheep
    (2023) Koca, Davut; Turgut, Ali Osman; Çetin, Nebi; Üner, Sefa; Gülendağ, Erman; Karagülle, Bahtiyar
    The objective of this study was to uncover the milk composition traits of Norduz sheep, which are bred in the Gürpınar district of the Van province, during the mid-term lactation period. The chosen ewes exhibited no signs of clinical or subclinical mastitis. A total of 104 sheep milk samples were meticulously collected to undergo comprehensive milk composition analysis. The chemical and physical attributes of Norduz sheep milk were methodically determined utilizing a milk autoanalyzer. The mean values for various milk constituents were as follows: milk fat (%), 2.48±0.11; solids-not-fat (SNF) (%), 10.76±0.08; milk protein (%), 5.09±0.04; lactose (%), 4.79±0.04; pH, 6.93±0.02; conductivity (mS/cm), 4.41±0.04; freezing point (°C), -0.602±0.80; salt (%), 0.8035±0.66; and density (kg/m3), 1039.73±0.39. Noteworthy negative and statistically significant correlations were observed between milk fat and protein (r=-0.36, p<0.001), milk fat and SNF (r=-0.32, p<0.001), as well as milk fat and lactose (r=-0.36, p<0.001). Conversely, positive and significant correlations emerged between SNF and milk protein (r=0.90, p<0.001), SNF and salt (r=0.87, p<0.001), and SNF and lactose (r=0.90, p<0.001). In summation, the protein content of Norduz sheep's milk exceeded that of the majority of sheep breeds reared in Türkiye. These findings carry the potential to make a valuable contribution to enhancing the milk composition of Norduz sheep.
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    Comparison of blood ?HBA 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.
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    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.
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    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.
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    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.
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    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.
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    Molecular Survey of the Toxoplasma gondii and Neospora caninum in brain tissue of aborted fetuses of Morkaraman sheep in Muş, Türkiye
    (2023) Koca, Davut; Çelik, Burçak Aslan; Çelik, Özgür Yaşar; Ayan, Adnan; Kılınç, Özlem Orunç; Turgut, Ali Osman; Ayan, Özge Oktay
    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.
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    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.
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    PAEP gene restriction fragment length polymorphism and its effects on milk composition in cross-bred Hamdani sheep
    (2024) Turgut, Ali Osman; Gülendağ, Erman; Koca, Davut; Üner, Sefa
    ?-lactoglobulin (?LG) stands as the primary whey protein in ruminant milk, synthesized by mammary gland cells during lactation and encoded by the ?LG gene. This study aimed to assess the impact of ?LG gene exon II polymorphism on milk composition traits in crossbreed Hamdani sheep. Sheep were examined for clinical diseases and mastitis. Milk and blood samples were only collected from healthy ewes. The composition and physical properties of milk were analyzed using milk autoanalyzer. The ?LG gene exon II region's 452 bp PCR products were subjected to RFLP analysis using the RsaI restriction enzyme. Two genotypes, AA and AB, were identified for the ?LG gene exon II region, with A and B allele frequencies of 0.7 and 0.3, respectively. Statistical analysis, conducted with Minitab® (Version: 19.2020.2.0), revealed that the AA genotype is associated with a higher milk fat percentage p<0.05). However, no significant genotype effect was observed for other milk composition traits in cross-bred Hamdani sheep. These results suggest that PAEP genotypes could serve as valuable indicators for enhancing milk composition in cross-bred Hamdani sheep through breeding programs.
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    Serum Anti-Mullerian Hormone Levels during Estrus and Diestrus Phases of the Estrous Cycle and its Possible Effect on Fertility in Cross-bred Hamdani Sheep
    (Univ Agriculture, Fac Veterinary Science, 2024) Turgut, Ali Osman; Koca, Davut
    This study aimed to assess the variations in serum Anti-mullerian hormone (AMH) levels during the estrus and diestrus phases of the estrous cycle and its effect on fertility in cross-bred Hamdani ewes. In the study, 21 non-prolific cross-bred Hamdani ewes (aged 2-3 years with BCS 2.75-3.25) were subjected to estrous synchronization using intra-vaginal sponges. Following synchronization, ewes underwent natural mating and pregnancy examination was carried out on the 45(th) day after mating through trans-rectal ultrasonography. Jugular blood samples were collected on day of estrus and 8 days later and analyzed for serum AMH and progesterone concentrations. Results showed that serum AMH levels were 100-480 and 95-520 pg/ml during estrus and diestrus phases, respectively. There was no change in serum AMH levels due to age, BCS and during estrus and diestrus phases of the estrous cycle (P>0.05). Estrus and diestrus serum AMH levels were significantly higher in pregnant ewes compared to non-pregnant ewes (P<0.05). Receiver-operating characteristic (ROC) analysis revealed that serum AMH cut-off value of >270 pg/mL was feasible to predict fertility in cross-bred Hamdani ewes. In conclusion, serum AMH can be used as a marker of fertility in non-prolific cross-bred Hamdani ewes.
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    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