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    Association among lipopolysaccharide, the transforming growth factor-beta superfamily, follicular growth, and transcription factors in spontaneous bovine ovarian cysts
    (ELSEVIER SCIENCE INC, 2020) Colakoglu, H. E.; Kuplulu, S.; Polat, I. M.; Pekcan, M.; Ozenc, E.; Baklaci, C.; Seyrek-Intas, K.
    The aim of this study was to investigate some of the growth and transcriptional factors originating from oocytes and granulosa cells in follicular fluid and to identify the relationships between the basic blood metabolite-metabolic hormones and intrafollicular lipo-polysaccharide (LPS) concentrations. Thirty cows included in the study were allocated into 2 groups comprising 15 cows with healthy preovulatory follicles (cyclic cows) and 15 cows with confirmed cystic follicles. The ovaries and uteri of all cows were assessed by transrectal ultrasonographic examination. Blood serum samples were collected at 15, 25, 35, 45, and 55 d after calving for analysis of nonesterified fatty acids, beta-hydroxybutyrate, insulin, glucose, IGF-1, ACTH, and cortisol. Ovaries and uteri were examined using transrectal ultrasound. Vaginal discharge was evaluated on the same days. Follicular fluid was also aspirated on days 35-55 from the healthy preovulatory follicles and cystic follicles using a transvaginal ovum pickup method. The densitometric levels of inhibin-a, growth and differentiation factor (GDF-9), bone morphogenetic protein (BMP-6), and GATA-4 and GATA-6 proteins were analyzed by the Western blotting technique; the concentrations of antimullerian hormone (AMH), IGF-I, estradiol-17 beta (E2), and progesterone (P4) were determined by ELISA; and the concentrations of LPS in the follicular fluid were measured by the Limulus amebocyte lysate test. The serum insulin, ACTH, and cortisol concentrations were higher in cystic cows than cyclic cows, but serum IGF-I concentrations were lower in cystic cows. The IGF-1 concentrations of cystic follicular fluids were lower, whereas AMH levels were significantly greater than those of healthy preovulatory follicular fluids. The cystic follicles had significantly lower expression levels of GDF-9, BMP-6, GATA-4, and GATA-6; in contrast, inhibin-alpha expression and LPS concentrations were significantly higher than in healthy preovulatory follicles. The proportion of pathologic vaginal discharge within 25 d postpartum in cystic cows were higher than in the cyclic group. In conclusion, it is suggested that intrafollicular dysregulation of the transforming growth factor-beta superfamily, growth, and transcriptional factors is affected by high intrafollicular LPS concentrations and systemic metabolic changes and these disturbances may be responsible for the generation of ovarian cysts. (C) 2019 Elsevier Inc. All rights reserved.
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    Associations between leptin, body condition score, and energy metabolites in Holstein primiparous and multiparous cows from 2 to 8 weeks postpartum
    (Ecole Nationale Veterinaire Toulouse, 2017) Colakoglu, H. E.; Polat, I. M.; Vural, M. R.; Kuplulu, S.; Pekcan, M.; Yazlik, M. O.; Baklaci, C.
    The present study aimed to investigate the relationship between serum leptin and body condition score (BCS) during the postpartum period in Holstein cows. We also explored the potential associations with other metabolic traits and fertility parameters. Primiparous and multiparous cows were subjected to leptin analysis on calving day. Starting at the second week postpartum, cows underwent seven weeks of weekly monitoring of serum concentrations of NEFA, BHB, leptin, cholesterol, AST, and bilirubin. During study, BCS changes were recorded, and the genital tract was assessed by ultrasonography and some fertility parameters were evaluated. During the study period, primiparous cows showed a lower mean BCS (P < 0.05). Leptin concentrations between calving and 8 weeks postpartum were higher in multiparous cows than primiparous cows (P < 0.001). Between postpartum weeks 2 and 8, primiparous cows showed higher concentrations of NEFA, BHB, and AST and lower cholesterol concentrations. Multiparous cows showed greater largest follicle diameters and ovulated earlier. Primiparous cows showed higher intervals of calving-to-first insemination and calving-to-conception, more insemination indices for the conception. Improved cow metabolic and reproductive performance was associated with lower concentrations of NEFA, BHB, and AST; higher concentrations of leptin and cholesterol; and greater BCS change during the early postpartum period. Delayed ovarian activity in primiparous cows might be caused by lower postpartum concentrations of leptin and cholesterol.
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    Does serum anti-Mullerian hormone levels always discriminate presence of the ovaries in adult bitches? Comparison of two ELISA kits
    (Wiley-Blackwell, 2016) Yagci, I. Pir; Pekcan, M.; Polat, I. M.; Kalender, H.; Macun, H. C.
    Anti-Mullerian hormone (AMH) is produced in the ovary, and thus, it is an excellent marker of follicle pool in females. Current interest is the clinical use of this parameter as a biomarker to assess presence or absence of an intact ovary and to diagnose ovarian remnant syndrome (ORS) following incomplete ovariohysterectomy (OHE) in bitches. The aim of this study was to evaluate serum AMH concentrations in bitches (n = 34) before and after OHE using two different commercial ELISA kits, one of which is based on detecting human AMH and the other is based on detecting human AMH and the other specified for canine AMH. Furthermore, serum AMH levels were also measured in six ORS cases to compare the diagnostic utility of the two different ELISA kits. Serum AMH concentrations measured using the human and canine kit prior to and after OHE were 0.32 +/- 0.24, 0.006 +/- 0.22 ng/ml (p<.001) and 12.08 +/- 22.81, 9.55 +/- 15.42 ng/ml (p=.868), respectively. Thus, the canine-based kit was not able to reveal the significant drop in serum AMH levels. In conclusion, the human-based ELISA kits successfully detected the drop in serum AMH concentrations. Reliable results can only be achieved from well-designed ELISA kits, and AMH levels might be a useful diagnostic tool for the evaluation of presence or absence of ovaries as well as for the detection of ORS cases in bitches.