title: Effect of propolis ethanol extract on myostatin gene expression and muscle morphometry of Nile tilapia in net cages.
abstract: Propolis can be used as growth enhancer due to its antimicrobial, antioxidant, and immune-stimulant properties, but its effects on morphometry and muscle gene expression are largely unknown. The present study evaluates the influence of propolis on muscle morphometry and myostatin gene expression in Nile tilapia (Oreochromis niloticus) bred in net cages. Reversed males (GIFT strain) with an initial weight of 170 ± 25 g were distributed in a (2 x 4) factorial scheme, with two diets (DPRO, commercial diet with 4% propolis ethanol extract and DCON, commercial diet without propolis, control) and four assessment periods (0, 35, 70, and 105 experimental days). Muscles were evaluated at each assessment period. Histomorphometric analysis classified the fiber diameters into four groups: <20 μm; 20-30 μm; 30-50 μm; and > 50 μm. RT-qPCR was performed to assess myostatin gene expression. Fibers < 20 µm diameter were more frequent in DPRO than in DCON at all times. Fiber percentages >30 µm (30-50 and > 50 µm) at 70 days were 25.39% and 40.07% for DPRO and DCON, respectively. There was greater myostatin gene expression at 105 days, averaging 1.93 and 1.89 for DCON and DPRO, respectively, with no significant difference in any of the analyzed periods. Propolis ethanol extract did not affect the diameter of muscle fibers or the gene expression of myostatin. Future studies should describe the mechanisms of natural products' effects on muscle growth and development since these factors are highly relevant for fish production performance.
authors.affiliation: Unidade Industrial de Rações, Integrada Cooperativa Agroindustrial, Londrina, PR, Brasil.
authors.forename: E L
authors.initials: EL
authors.lastname: Buck
authors.affiliation: Departamento de Zootecnia, Programa de Pós-Graduação em Ciência Animal, Universidade Estadual de Londrina, Londrina, PR, Brasil.
authors.forename: I Y
authors.initials: IY
authors.lastname: Mizubuti
authors.affiliation: Departamento de Medicina Veterinária Preventiva, Programa de Pós-Graduação em Ciência Animal, Universidade Estadual de Londrina, Londrina, PR, Brasil.
authors.forename: A A
authors.initials: AA
authors.lastname: Alfieri
authors.affiliation: Departamento de Medicina Veterinária Preventiva, Programa de Pós-Graduação em Ciência Animal, Universidade Estadual de Londrina, Londrina, PR, Brasil.
authors.forename: R A A
authors.initials: RA
authors.lastname: Otonel
authors.affiliation: Faculdade de Veterinária, Universidade Filadélfia, Londrina, PR, Brasil.
authors.forename: L Y
authors.initials: LY
authors.lastname: Buck
authors.affiliation: Departamento de Zootecnia, Programa de Pós-Graduação em Ciência Animal, Universidade Estadual de Londrina, Londrina, PR, Brasil.
authors.forename: F P
authors.initials: FP
authors.lastname: Souza
authors.affiliation: Departamento de Zootecnia, Programa de Pós-Graduação em Ciência Animal, Universidade Estadual de Londrina, Londrina, PR, Brasil.
authors.forename: O P
authors.initials: OP
authors.lastname: Prado-Calixto
authors.affiliation: Departamento de Zootecnia, Programa de Pós-Graduação em Ciência Animal, Universidade Estadual de Londrina, Londrina, PR, Brasil.
authors.forename: A R
authors.initials: AR
authors.lastname: Poveda-Parra
authors.affiliation: Universidade Estadual de Maringá, Campus Regional do Noroeste, Diamante do Norte, PR, Brasil.
authors.forename: L
authors.initials: L
authors.lastname: Alexandre Filho
authors.affiliation: Departamento de Zootecnia, Programa de Pós-Graduação em Ciência Animal, Universidade Estadual de Londrina, Londrina, PR, Brasil nmlopera@uel.br.
authors.forename: N M
authors.initials: NM
authors.lastname: Lopera-Barrero
mesh_terms: D000818:Animals; D017756:Aquaculture / Q000379:methods; D023681:Cichlids / Q000033:anatomy & histology* / Q000235:genetics; D000431:Ethanol / Q000008:administration & dosage* / Q000737:chemistry / Q000494:pharmacology; D029941:Fish Proteins / Q000235:genetics; D005786:Gene Expression Regulation / Q000187:drug effects; D008297:Male; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000648:ultrastructure; D055435:Myostatin / Q000235:genetics*; D009929:Organ Size / Q000187:drug effects; D010936:Plant Extracts / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology; D011429:Propolis / Q000737:chemistry*
chemical_list: D029941:Fish Proteins; D055435:Myostatin; D010936:Plant Extracts; D000431:Ethanol; D011429:Propolis