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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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    Rumination Time and Physical Activity Monitoring, Milk Yield Changes Around Estrus and First Service Pregnancy Rate in Dairy Cows Assigned to Voluntary Waiting Period
    (Israel Veterinary Medical Assoc, 2018) Yazlik, M. O.; Colakoglu, H. E.; Polat, I. M.; Aloglu, E.; Baklaci, C.; Kaya, U.; Kuplulu, S.
    In high milk-yielding dairy cows, the energy balance challenges in early lactation and impact reproductive performance often affects estrus intensity, duration and detection. This study determined the role of a voluntary waiting period on rumination time, physical activity and milk yield changes during the peri-estrus period in the first service and further fertility in high-yielding dairy cows. To the best of our knowledge, this is the first study to demonstrate a relationship between voluntary waiting period and estrus-related parameters. This study was conducted on 145 Holstein-Friesian dairy cows aged 2 to 6 years of age. Cows were assigned a short voluntary waiting period, 45 to 70 day in milk (SVWP; n=73), and the long voluntary waiting period, 71 to 95 day in milk (LVWP; n=72). Rumination time, physical activity and milk yield changes around estrus in the first service were detected by an automated monitoring system. Artificial insemination procedures were performed between 45 to 70 days in milk for SVWP and 71 to 95 days in milk for LVWP. The barn's daily temperature and humidity index (THI) was recorded throughout the study period and was <72. Basal rumination time were significantly lower in SVWP (376.82 +/- 74.58 min/clay) than LVWP group at the day of estrus (352,07 +/- 68.90 min/day) (P<0.01). First service pregnancy rate was 23.72% and 38.46% in short and long voluntary waiting period, respectively (p<0.05). Physical activity intensity and milk yield changes were similar among groups during the peri-estrus period and on the day of estrus. The results indicated that the short voluntary waiting period was associated with the lower basal rumination time around estrus and lower first service pregnancy rate.