Effects of Supplementation with Bee Pollen and Propolis on Growth Performance and Serum Metabolites of Rabbits: A Meta-Analysis.

The objective of this study was to evaluate the effects of bee pollen (BP) and propolis (PRO) supplementation on rabbits' productive performance and serum metabolites through a meta-analysis. Sixteen peer-reviewed publications were included in the data set. The rabbit strains used in the studies included in the data set were New Zealand White, V-line, Rex, and V-line crosses. Weighted mean differences (WMD) between treatments supplemented with BP or PRO and control treatments were used to assess the magnitude of the effect. BP supplementation decreased ( < 0.001) daily feed intake (DFI) and feed conversion ratio (FCR); however, increased ( < 0.001) average daily gain (ADG) and hot carcass yield (HCY). PRO supplementation reduced DFI ( = 0.041) and FCR ( < 0.001), and increased ADG ( < 0.001) and HCY ( = 0.005). In blood serum, BP supplementation increased total antioxidant capacity (TAC; = 0.002) and decreased serum creatinine concentration ( = 0.049). Likewise, decreased serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and malondialdehyde (MDA) were detected in response to BP supplementation ( < 0.05). PRO supplementation increased the TAC in blood serum ( = 0.018); however, decreased serum concentrations of AST, ALT, and MDA were observed ( < 0.05). In conclusion, BP or PRO supplementation can be used as a natural growth promoter in rabbits, and both can also improve rabbits' antioxidant status. However, BP or PRO supplementation does not affect rabbits' renal or hepatic health status.