13. Quality over Quantity: The Oxygen Advantage of Bee Pollen Supplementation.

Abstract Physiological expansions in blood volume can often outpace red blood cell (RBC) production under conditions such as growth, sexual behavior, or nutritional supplementation. This mismatch often causes hemodilution, reducing the ratio of RBCs to plasma and lowering hemoglobin (HGB) concentration. When hemodilution is excessive, systemic oxygen delivery may be compromised due to lower oxygen-carrying capacity of the blood. Measuring anemia’s parameters (Hematocrit [HCT], mean corpuscular volume [MCV], mean corpuscular hemoglobin [MCH], and HGB) can help capture both the quality and quantity of oxygen delivery by reflecting RBC size, HGB amount, and overall oxygen-carrying capacity. Low HCT can indicate hemodilution, while MCV and MCH reflect cellular adaptations that affect oxygen delivery, and HGB reflects total oxygen availability. In addition, FAMACHA scores can be used to assess clinical anemia. Bee pollen (BP), a nutrient-dense supplement rich in proteins, minerals, amino acids, and antioxidants, may reduce anemia and the oxygen-delivery limitations associated with hemodilution by enhancing RBC size, HGB density, and functional efficiency rather than increasing total RBC mass. Crossbred dams (Boer ´ Spanish n = 35) were randomly assigned to supplemented BP (T-BP: n = 18) or control (T-CTL: n = 17). T-BP received 1 g of BP per kilogram of body weight, daily administered orally via syringe. BP was prepared using a 1:1 water mixture. T-CTL individually received 90 mL of water orally via syringe. Both groups were fed the same maintenance diet, including Bermuda hay, corn, and pellets. The experiment was conducted during the decreasing photoperiod (October to November, Northern Hemisphere) and lasted 54 days, including 10 days for adaptation to diet and handling. FAMACHA scores and blood parameters were collected via jugular venipuncture for CBC analysis on days -12, 0, 20, and 41. Key indicators included MCV, MCH, HCT, and HGB. Each animal was considered an experimental unit, and data were analyzed using mixed models and repeated measures of SAS. Significance was declared at P ≤ 0.05. Across the experiment, MCV was higher in T-BP than T-CTL (T-BP: 15.76 vs. T-CTL: 15.59 fL; P < 0.05), and MCH was also increased (T-BP: 5.48 vs. T-CTL: 5.28 fL; P < 0.05), suggesting macrocytic RBC. HCT differed between treatments (T-BP: 31.18% vs. T-CTL: 29.63%; P ≤ 0.05), reflecting RBC characteristics rather than an increased number. HGB concentrations (T-BP: 10.23 g/dL vs. T-CTL: 10.01 g/dL; P > 0.05) and FAMACHA scores (T-BP: 2.7 vs. T-CTL: 2.9; P > 0.05) were similar between treatments. In conclusion, despite no change in the total number of HGB or FAMACHA scores, BP supplementation was associated with higher MCV and MCH values, suggesting possible improvements in RBC characteristics. These changes may enhance oxygen transport efficiency under subclinical stress, suggesting that supplementation, such as BP, could improve microscopic blood quality without altering visible health indicators.