Fig. 5

Daily dynamic phosphorus feeding regimen improved MB remodeling in 70-week-old Hy-Line Brown laying hens for 12 weeks. A) serum calcium (n = 6 per group); B) serum phosphorus (n = 6 per group); C) calcium content of MB (n = 6 per group); D) phosphorus content of MB (n = 6 per group); E) calcium/phosphorus ratio of MB (n = 6 per group); F) area percentage of MB analyzed by toluidine blue staining (n = 3 per group); G) representative images of toluidine blue staining of femur transverse sections, bar represents 100 µm. Data are presented as the mean ± SEM. P < 0.05 by one-way ANOVA followed by Duncan's multiple range tests, the letters (A, B) and the letters (a, b) indicate significant differences among all treatment groups chosen from 6 h post-oviposition and 18 h post-oviposition, respectively (P < 0.05). The significance of difference between 6 h and 18 h post-oviposition for each group was analyzed using two-tailed students’ t-tests, ^*P < 0.05, ^**P < 0.01, ^***P < 0.001. RR, provided with regular phosphorus diet at both 09:00 and 17:00 for 12 weeks; RL, provided with regular phosphorus diet at 09:00 and low phosphorus diet at 17:00 for 12 weeks; LR, provided with low phosphorus diet at 09:00 and regular phosphorus diet at 17:00 for 12 weeks; LL, provided with low phosphorus diet at both 09:00 and 17:00 for 12 weeks; MB, medullary bone