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    Evaluation of the Accuracy and Performance of Two Commercial Pregnancy‐Associated Glycoprotein Tests for Early Pregnancy Detection in Cows
    (Wiley, 2025-01-28) Tarik Safak; Kenan Çağrı Tümer; Yağmur İpek Alp; Taha Yasin Özen; Oznur Yilmaz‐Koc
    The aim of this study was to determine and compare the diagnostic accuracies of two commercial pregnancy-associated glycoprotein tests, Alertys OnFarm Pregnancy Test (AOPT) and Alertys Milk Pregnancy Test (AMPT), for early pregnancy diagnosis in dairy cattle. Holstein cows (n = 124) were used in the study. Whole blood samples were collected from the jugular vein 28 days after fixed-time artificial insemination (FTAI). In addition, teats of these cows were swabbed and milk samples were collected into sterile Falcon tubes. AOPT was performed on the farm within 2 h after whole blood collection. Milk samples for AMPT analysis were taken to the laboratory and analysed within 2 h. Transrectal ultrasonography was performed on the 32nd day after FTAI as a reference test. Comparative evaluation was made according to the AOPT and AMPT results, 28 days after FTAI. The sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) for the AOPT were 92.4%, 80.0%, 87.9%, 89.0% and 85.7% and for AMPT were 97.5%, 82.2%, 91.9%, 90.6% and 94.9% respectively. Cohen's kappa statistic showed a 91.9% agreement (kappa = 0.820, p < 0.001) between the reference test and AMPT, and an 87.9% agreement (kappa = 0.735, p < 0.001) between the reference test and AOPT. AOPT and AMPT offers a reliable, non-invasive (in milk) and practical approach to pregnancy diagnosis in cows. These methods enable early pregnancy detection and can be easily integrated into farm routines, enhancing reproductive management and overall herd productivity.
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    Evaluation of β-hydroxybutyrate, calcium, and non-esterified fatty acids at day one postpartum in predicting the risk of diseases in dairy cows
    (University of Veterinary Sciences Brno, 2024) Tarik Safak; Efe Durukan; Oznur Yilmaz-Koc; Ali Risvanli; Berrak Isik Soyturk; Metin Bayraktar
    In this study, the usability of calving type, non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHB), and calcium (Ca) concentrations in predicting postpartum diseases was examined. For this purpose, 120 Holstein cows were used in the study. These cows were divided into two subgroups according to the calving type: unassisted parturition (eutocic, n = 58) and assisted parturition (dystocia, n = 62). Cows were followed for 15 days postpartum. Diseases of retained foetal membranes (RFM), metritis, and clinical mastitis that developed in the postpartum period were recorded. Then, NEFA, BHB, and Ca concentrations were measured in blood samples collected at parturition from cows with RFM (n = 19), metritis (n = 34), clinical mastitis (n = 20) and cows that did not develop the disease (n = 47). Our results show the decreased Ca concentration to be positively associated with the risk of mastitis (P < 0.001, odds ratio [OR] 4.599), metritis (P = 0.008, OR 4.286), and RFM (P < 0.001, OR 5.016); and increased BHB concentration to be positively associated with the risk of metritis (P = 0.002, OR 4.069) and RFM (P < 0.001, OR 9.498). The results of the study indicated that low Ca and high BHB concentration at parturition could negatively affect the productive efficiency of dairy cows.
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    Interpretable Artificial Intelligence for Analysing Changes in Gases in the Uterine Environment of Cows According to Physiological Structures in the Ovary
    (Wiley, 2025-02-19) Ali Risvanli; Burak Tanyeri; Güngör Yildirim; Yetkin Tatar; Mehmet Gedikpinar; Hakan Kalender; Tarik Safak; Burak Yuksel; Burcu Karagulle; Oznur Yilmaz Koç; Cebrail Barut; Mehmet Akif Kilinc
    The objective of the present study was to examine the relationship between the gases in a cow's uterine environment and its ovarian physiological structures using the sunflower optimisation algorithm (SFOA) deployed in a device called Metrisör, developed by our project team. A total of 500 uteruses obtained from slaughtered cows served as the experimental sample. Gas measurements were taken from 489 uteruses with no clinical metritis or microbiological growth. Additionally, the diameters of the corpus luteum and follicles in the ovaries were measured using callipers. These results were then analysed based on the presence or absence of a corpus luteum (CL) and follicles larger or smaller than 1.5 cm. According to uterine gas fluctuations, the presence and absence of CL could be detected at rates of 80.60% and 79.60%, respectively. Also, based on uterine gas changes, the presence of ovarian follicles larger than 1.5 cm was determined 82% of the time, and the presence of follicles smaller than 1.5 cm was determined 80% of the time. In conclusion, it was found that different stages of a cow's sexual cycle might involve changes in uterine gases. Thus, the data from this study may enable the development of a new estrus detection method for cows.