THE USE OF BIOLOGICALLY ACTIVE SUBSTANCES FOR STRENGTHENING OF RESISTANCE TO DISEASES OF HONEYBEE COLONIES APIS MELLIFERA
Valentina Cebotari, I. Toderaş, I. Buzu
Abstract
The purpose of researches lies in cultivation and testing the bee food for some nutritional supplements (remedies) with high content of biologically active substances, in particular of proteins and microelements (Fe and Se), and working out the processes for bee families feeding in order to strengthen their resistance to overwinter and diseases. So, was cultivated the strain of cyanobacteria Spirulina platensis CNM-CB-02 in presence of selenite of Fe (III) hex hydrate - FeSeO3 6H2O, given as part of nutritious environment in amount of 30 to 35 mg/L, first three days of cultivation. Subsequently, was obtained the extract from nominated biomass, by extracting of biologically active substances with an alcoholic solution of 20 to 30%, with sediment isolation from supernatant, drying of isolated sediment, double extracting with 0.45% NaOH solution of biologically active substances, combining of obtained supernatants and making of dialyze up to 7.5 - 8.5 pH, and finally obtaining the supplement, named by us "Apispir+Fe+Se". At the end of august 2010 and early April 2011, have been carried out comparative testing experiences of this supplement on bee colonies from three batches (table), within ten families in each batch. Test results have shown that feeding bees with nutritional supplement "Apispir+Fe+Se", at the end of august, during reduced harvest, has contributed to significantly higher overwintering resistance with 10.5 - 19.5% (P<0.001). Feeding bees with nutritional supplement "Apispir+Fe+Se", in the spring, at the beginning of April, during reduced harvest, has contributed to significantly higher disease resistance of bee colonies (measured by the test of hygiene speed and removal of dead brood from the comb cells), on the 15th day - with 8.4 - 18.5% (P<0.001). Disease resistance remained higher at experimental groups also in June. Bee colonies from IIIrd experimental group, which have got in food nutritional supplement "Apispir+Fe+Se", had a higher resistance to diseases, compared with IInd and Ist batches, with 7.9 to 15.5% (P<0.001). The generalized result of using the nutritional supplement "Apispir+Fe+Se" consists in strengthening the bee immunity, conducting to their higher overwintering and disease resistance, also decreasing of their morbidity and mortality.