Effects of zinc supplementation (organic and inorganic) on antioxidant system gene expression of Apis mellifera L. honey bees

• Grant number: 19/01138-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2019
• End date: October 31, 2020
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Production
• Principal Investigator: Ricardo de Oliveira Orsi
• Grantee: Iloran do Rosário Corrêa Moreira
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Apis mellifera worker bees present polyethylism behavior, the division of labor within the colony according to their physiological age or colony necessities. In its internal nest activities, the metabolic rate is reduced and the damages caused by oxidative stress are reduced. However, in the stage forragers they need to forage large areas to collect food resources, increasing significantly their metabolism and consequently their more susceptible to the production of reactive species production that can promote severe cellular damages, leading to premature aging. To minimize this effect, A. mellifera has a system of antioxidant enzymes that degrade the compounds that produce damages, supporting the organic balance. Among the minerals, zinc can improve the antioxidant system, so deficiency of this mineral can affect the functioning of the antioxidant system enzymes. Thus, the hypothesis of the present proposal is to verify if the of zinc supplementation (inorganic and organic) can help in the proper functioning of the antioxidant system of bees and in the increase of vitellogenin (protein main that carrier of zinc) by gene expression analysis. For this, 15 colonies of A. mellifera bees will be submitted to the following treatments: Zn0 (Control), ZnO50 (50 mg L-1 Zinc-methionine) and ZnI50 (50 mg L-1 Zinc Sulphate Monohydrate), supplied in sugar syrup. Zinc levels will be confirmed by Flame Atomic Absorption Spectrometry (FAAS). For the analysis of zinc action in the antioxidant system of foragers bees (seven days old) will be analyzed the expression of catalase, glutathione peroxidase and vitellogenin genes, using the rp49 gene as a control. Bee mortality and population development will also be evaluated. The results of mortality and population development will be by analysis of variance (ANOVA) followed by Tukey test for comparison of means. For the results of gene expression will be used the Dunnet test. In all tests, results will be considered statistically different when P <0.05. This project is expected to provide important information on nutrition and the effects zinc can have on the antioxidant system balance of bees.