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Hachiro Kamada 아세아·태평양축산학회 2017 Animal Bioscience Vol.30 No.3
Objective: The effects of the pre- and postpartum supplementation of cows with Se on their plasma P4 concentrations after calving were investigated. Methods: Thirty-four Holstein cows were used to investigate the effects of dietary selenium supplementation on the postpartum recovery of the luteal function in cows. Selenium-rich yeast (containing 300 ppm selenium) was mixed with total mixed ration fed to 17 pregnant cows from 30 days before they were due to calve (10 g yeast daily) to 100 days after calving (20 g yeast daily). The control cows (n = 17) were fed the same amount of ordinary yeast. The cows’ plasma progesterone concentrations were determined every two days using an enzyme immunoassay after calving. Results: Feed intake (total digestive nutrient, crude protein), milk production, body weight and the biochemical properties of blood plasma did not differ between the two groups; however, the plasma selenium concentrations of the supplemented animals were significantly greater than those of the controls at and after calving. The postpartum plasma progesterone concentrations of the selenium-yeast-supplemented group increased earlier than those of the control group. Moreover, during the estrus cycle after the 3rd ovulation or ovulation with estrus between 60 to 80 days after calving, the selenium-supplemented cows exhibited greater progesterone concentrations than the control cows. Conclusion: Selenium supplementation promotes the postpartum progesterone production of cows.
Hachiro Kamada Asian Australasian Association of Animal Productio 2023 Animal Bioscience Vol.36 No.3
Objective: 12-oxo-5Z,8Z,10E,14Z-eicosatetraenoic acid (12-KETE), a metabolite of arachidonic acid, is a strong candidate signal for placenta separation following calf discharge at delivery. In the present study, the effects of 12-KETE on bovine trophoblast cells were investigated to determine its function in the placentome at delivery. Methods: Bovine trophoblast cells derived from blastocysts were used. They were cocultured with or without fibroblasts derived from bovine placentome and/or bovine uterine epithelial cells. 12-KETE was added to the culture medium. Results: Bovine trophoblast cells contained binucleate cells and strongly expressed caudal type homeobox 2 (CDX-2) genes. Addition of 12-KETE to the trophoblast cell colony without feeder cells or that on a fibroblast monolayer induced rapid exfoliation of the colony. After 12-KETE addition, trophoblast cells emitted strong fluorescence caused by the degradation of dye-quenched collagen, indicating that 12-KETE activated matrix metalloproteinase of the trophoblast cells. Exfoliated cell colonies were stained with YOPRO-1, but not propidium iodide (PI). Moreover, DNA fragmentation and Bcl-2 associated X protein (Bax) gene (apoptosis stimulator) upregulation were observed in exfoliated cells, indicating that 12- KETE induced trophoblast cell apoptosis. These results were consistent with previous in vivo observations; however, even a lower concentration of 12-KETE activated trophoblast protease. Meanwhile, fibroblasts derived from the bovine placentome converted arachidonic acid to 12-KETE. Conclusion: These observations indicate that 12-KETE may serve as a signal for placenta separation at delivery.
Kamada Hachiro,Matsui Yoshitaka 아세아·태평양축산학회 2023 Animal Bioscience Vol.36 No.9
Objective: We aimed to determine the effects of 12-oxoeicosatetraenoic acid (12-KETE)- induced placenta release on the performance of mother cows (milk yield, ovarian function, and blood plasma biochemical properties). Methods: Experimental treatments were as follows: i) natural delivery including natural placental release (control cows); ii) induced calf delivery with placental retention (RP cows); and iii) induced calf delivery and 12-KETE-induced placental release (KE cows). Delivery in pregnant KE cows was induced with dexamethasone and prostaglandin. These cows were injected with 12-KETE after calf discharge, resulting in the release of the fetal placenta. RP cows were not treated with 12-KETE after inducing delivery, resulting in placental retention. Results: The milk yield in RP cows during the first 50 days after delivery was significantly lower than that in control cows (p<0.05), whereas KE cows exhibited a similar milk yield to that of control cows. The postpartum plasma progesterone levels of control cows increased 14 days after delivery on average; however, its increase was delayed by 10 days in RP cows. Meanwhile, the 12-KETE treatment (KE cows) brought the timing of progesterone increase forward to the normal level (control cows). Among the 20 biochemical parameters examined, the total cholesterol levels in blood plasma 14 days after delivery were lower in RP cows than that in the other two treatment groups (control cows and KE cows) (p<0.05). In addition, the plasma level of haptoglobin tended to be low in cows that discharged their placentas shortly after delivery. Conclusion: These findings indicate that 12-KETE treatment can alleviate the disorder caused by placental retention.