Effects of red ginseng by-product supplementation in pollen substitute patties on colony strength of Apis mellifera

This study evaluated the effects of pollen substitute patties supplemented with graded levels of red ginseng by-product (RGBP) on Apis mellifera colonies.Saponin content, nutritional composition, colony strength, sealed brood ratio, feed consumption, and adult worker population were assessed.As the inclusion level of RGBP increased from 0.5 to 10.0% (w/w), crude saponin content in the pollen patty increased proportionally, ranging from 22.0 to 140.7 mg•100 g -1 .With increasing supplementation levels, total carbon and crude fiber contents slightly increased, whereas crude protein and crude fat contents decreased.Mineral contents of Ca, K, and Fe increased slightly, except for phosphorus.During the feeding period from June to October, colony strength and brood development differed among treatments.Colonies fed pollen patties containing 0.5 -1.0%RGBP showed increased numbers of combs and higher sealed brood ratios compared with the control.In contrast, higher inclusion levels (≥ 2.5%) resulted in gradual reductions in colony growth and brood development.Feed consumption was comparable between the control and 0.5 -1.0% treatments, whereas higher supplementation levels reduced pollen patty intake, particularly at 10.0%.Prior to overwintering, colonies fed pollen substitute patties supplemented with 0.5 -1.0%RGBP exhibited significantly greater adult worker populations compared with the control (p < 0.05), whereas colonies receiving ≥ 2.5% supplementation showed reduced worker numbers.These findings indicate that moderate supplementation levels (0.5 -1.0%) enhance colony strength without negatively affecting feed consumption.