Department of Animal Science & Technology, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian, 271018, Shandong, P. R. China.
Department of Animal Science & Technology, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Shandong Agricultural University, Taian, 271018, Shandong, P. R. China.
Poult Sci. 2022 Apr;101(4):101736. doi: 10.1016/j.psj.2022.101736. Epub 2022 Jan 17.
Calcium and phosphorus homeostasis is crucial for the performance and bone health of laying hens. The calcium and phosphorus transporters play an important role in calcium and phosphorus absorption, reabsorption, and excretion. In the present study, Hy-Line Brown layers were sampled at brooding period (1, 4, 6 wk), growing and developing period (12, 18 wk) and laying period (20, 28, 80 wk) respectively, and the calcium transporters CaBP-D28k and PMCA1b and phosphorus transporters NPt2a and NPt2b were respectively measured in duodenum, jejunum, ileum and kidney. The result showed that serum calcium increased (P < 0.0001) and phosphorus level fluctuated (P = 0.0019), while alkaline phosphatase activity decreased with age (P < 0.0001). The mRNA and protein expressions of CaBP-D28k in small intestine elevated after maturity (P ≤ 0.0001). In contrast, the PMCA1b mRNA showed a trend to increase with age in jejunum (P = 0.0059) and ileum (P = 0.0825) whereas there was a decrease for PMCA1b protein in 12-18 wk (P ≤ 0.0009). The peak of NPt2b mRNA were observed at 28 wk in duodenum (P = 0.0001) and jejunum (P = 0.0622) and 1 wk in ileum (P < 0.0001). The NPt2b protein expression reached the top point at 4 or 6 wk and 20 wk and decreased to the lowest point around 12 wk (P ≤ 0.0850). In kidney, CaBP-D28k mRNA was not influenced by age (P = 0.4999), while PMCA1b highly expressed in 6-12 wk (P = 0.0003). The protein expressions of CaBP-D28k (P = 0.0148) and PMCA1b (P = 0.0003) decreased with age and lowly expressed in 12-18 wk and increased thereafter. In contrast, NPt2a expression increased steadily with age and decreased at 80 wk (P < 0.0001). In conclusion, the expressions of intestinal calcium and phosphorus transporters were changed by age, intestinal CaBP-D28k and renal NPt2a showed a dramatic increase after maturity, which coincide with the increased calcium and phosphorus requirement for egg production.
钙磷稳态对蛋鸡的生产性能和骨骼健康至关重要。钙磷转运蛋白在钙磷的吸收、重吸收和排泄中发挥着重要作用。本研究分别在育雏期（1、4、6 周）、生长发育期（12、18 周）和产蛋期（20、28、80 周）采集海兰褐蛋鸡样本，测定十二指肠、空肠、回肠和肾脏中钙转运蛋白 CaBP-D28k 和 PMCA1b 以及磷转运蛋白 NPt2a 和 NPt2b 的表达。结果表明，血清钙随日龄增加而升高（P＜0.0001），磷水平波动（P＝0.0019），碱性磷酸酶活性随日龄降低（P＜0.0001）。小肠 CaBP-D28k 的 mRNA 和蛋白表达在成熟后升高（P≤0.0001）。相反，空肠和回肠中 PMCA1b mRNA 随日龄呈增加趋势（P＝0.0059 和 P＝0.0825），而 PMCA1b 蛋白在 12-18 周下降（P≤0.0009）。十二指肠和空肠中 NPt2b mRNA 的表达高峰在 28 周（P＝0.0001 和 P＝0.0622），回肠在 1 周（P＜0.0001）。NPt2b 蛋白表达在 4 或 6 周和 20 周达到最高点，在 12 周左右降至最低点（P≤0.0850）。肾脏中，CaBP-D28k mRNA 不受年龄影响（P＝0.4999），而 PMCA1b 在 6-12 周高度表达（P＝0.0003）。CaBP-D28k（P＝0.0148）和 PMCA1b（P＝0.0003）蛋白表达随日龄降低，12-18 周表达较低，此后增加。相反，NPt2a 表达随日龄稳定增加，80 周时降低（P＜0.0001）。总之，肠道钙磷转运蛋白的表达随日龄变化，空肠 CaBP-D28k 和肾脏 NPt2a 在成熟后显著增加，这与产蛋对钙磷需求的增加相吻合。
