Nutritive Evaluation of Bee Pollen Collected in a Suburban Area
Author(s)
Date Issued
2022
Type
conferenceObject
Abstract
Adequate pollen nutrition is a basic condition for good growth and development of
honey bees (HB). However, it can be expected that locally environmental conditions can
play a role on the nutrition of HB colonies through the diversity pollen. Two ex-hive trials
were performed to evaluate the nutritive value of bee pollen collected in a suburban area
(Viterbo, Central Italy) where an experimental apiary was established in the frame of
PLANT-B, an European project funded by the PRIMA Foundation (grant n. 1812). From March
to August 2021 pollen was collected monthly. A queen (50% membership to the subspecie
Apis mellifera ligustica Spin.) was caged in a honeycomb and, and the comb with capped
brood was moved to an incubator till the emergence of young workers. Groups of 30 0-24
h HB were collected and then moved into small cages provided with solid diets, water and
sugar solution 50% w/w (SS50) ad libitum. The cages were incubated at 28°C and at 70%
relative humidity. Six pollen-based diets (levelled on the dry matter) and two controls,
no pollen or Haydak’s formulation, were set up. Each thesis was replicated three times.
All solid the diets were subjected to centesimal analysis to determine their composition.
Every day for 2 weeks, deceased HB were counted and removed, and the consumption (μl/
bee/day) of water and SS50 was recorded; solid diets were replaced every two days and
the consumption (mg dry matter/bee/day) was measured. Survival rate and daily weight
gain (DWG) were calculated at the end of the trials. The diet had a significant effect (p
< 0.01) on DWG. In detail, the pollen of April, May, and July were the ones that showed
higher HB weight gain at 14 days versus Haydak’s diet and the no pollen thesis. In contrast,
the treatment does not affect SS50, water consumption and survival rate. The higher dry
matter intake correlated with DWG (r = 0.70, p < 0.01) and the DWG correlated with all the
nutritional components, especially with crude protein (p<0.01). Concluding, the biological
composition of pollen influences the DWG but further investigation must be conducted on
field.
Conference(s)
EurBee 9 - 9th European Congress of Apidology