Dose-Dependent Impact of Bee Pollen Supplementation on Macroscopic and Microscopic Structure of Femoral Bone in Rats

SIMPLE SUMMARY: Bee pollen is considered an interesting feed supplement with beneficial health impacts. It contains many basic nutritional compounds that improve growth performance, development and immune response of animals. However, its effect on bone structure has been studied to a limited extent and the results published so far are ambiguous. Therefore, the impact of bee pollen supplementation on selected bone characteristics of rats was investigated in our study. We determined a dose-dependent effect of bee pollen administration on macroscopic and microscopic structure of femoral bone. Several negative effects of bee pollen supplementation at the level of 0.75% on bone features have been demonstrated, while the level of 0.5% did not influence these properties in rats. ABSTRACT: Bee pollen has been successfully used as a feed additive with beneficial impacts on productive, reproductive, and immune conditions of animals. However, its effect on bone structure and bone health remains controversial. Therefore, the purpose of our study was to examine the impact of bee pollen supplementation on macroscopic and microscopic structure of a femoral bone using rats as suitable animal models. Male rats (1 month-old) were assigned into three groups: control (C group) that was fed a standard diet without bee pollen and two bee pollen supplemented groups (P1 and P2 groups) that received an experimental diet including 0.5% and 0.75% of bee pollen, respectively, for 3 months. A number of unfavorable effects of 0.75% bee pollen administration on bone weight, cortical bone thickness, calcium content, alkaline phosphatase activity, sizes of primary osteons’ vascular canals, Haversian canals and secondary osteons in the cortical bone have been recorded, whereas these bone parameters were significantly decreased in the P2 group versus the C group. On the contrary, the concentration of 0.5% did not affect any of bone features mentioned above. In conclusion, the impact of bee pollen supplementation on femoral bone structure of rats depends on the dose used.