Protein supplementation on longevity and gene expression related to the detoxification system of Apis mellifera bees exposed to the lethal dose of Fipronil inseticide

• Grant number: 17/24941-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2018
• End date: June 30, 2018
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Production
• Principal Investigator: Ricardo de Oliveira Orsi
• Grantee: Bianca Gomes Sassaki
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Studies have shown that protein supplementation can increase the amount of protein in the hemolymph of bees and improve their resistance to contamination by agrochemicals, such as fipronil. Thus, the objective of the present proposal is to evaluate the effect of protein supplementation on longevity and gene expression related to the detoxification system of Apis mellifera bees exposed to the lethal dose of the agrotoxic Fipronil. For this, two experiments will be performed to evaluate the effect of protein supplementation during larval development (E1) and during the first six days of adult life (E2). For E1 will be used 06 hives distributed in the following treatments: T1 Control - without protein supplementation; and T2 - ration with 25% of crude protein that will be offered weekly in the amount of 200g / colony. Four weeks after the initiation of protein supplementation, newly emerged bees will be marked with non-toxic pen and reintroduced into observation hives containing one open brood frame and queen of their respective swarms. On the sixth day after reintroduction, sugar syrup containing or not containing LD50% of the pesticide fipronil (0.009 ± 0.003 ¼g / bees) will be provided. After 12 and 24 hours, 10 labeled bees will be recaptured in each observation hive, immediately frozen for RNA extraction and evaluation of the cytochrome P450 gene expression. The remaining bees will be evaluated for longevity, with a daily mortality record. The protein will be quantified by the Bradford method, with spectrophotometer reading at 595 nm, using bovine serum albumin as standard. For E2, newly emerged bees of six clusters kept under natural feeding (without supplementation) will be marked, reintroduced in observation hives containing one open brood frame and queen, of their respective swarms, and submitted to the same treatments of E1, for the period of six days. Afterwards, sugar syrup containing or not containing LD50% of the agrochemical fipronil (0.009 ± 0.003 ¼g / bees) will be supplied. Harvesting the bees, gene expression analysis procedures and longevity will be the same as described above. The results will be evaluated using Student's t-test and will be considered statistically different when P <0.05. (AU)