title: Vitamin C supplementation has no effect on American bullfrog's immune response.
abstract: American bullfrog (Lithobates catesbeianus) is the only species raised in Brazilian commercial frog farms, and the intensive culture of these animals has gained great popularity in Brazil over the past several years. Stress is one of the major obstacles in frog culture. To minimise this problem, the aim of the present study was to investigate the role of added vitamin C in the diet of American bullfrogs as an antistress factor through the assessment of plasma corticosterone, leucocyte levels and macrophage activation in animals raised in confinement. The experimental design was entirely randomised, with six treatments (supplementation of 0, 250, 500, 750, 1000 and 2000 mg of vitamin C/kg of feed) and four replications. The plasma corticosterone level, leucocyte level and macrophage activation were evaluated. It was concluded that vitamin C had no influence on the evaluated parameters due to the possible adaptation of the animals to life in captivity (domestication). The results of this research indicate that farmers should not increase the levels of vitamin C in commercial feeds because this would only enhance production costs.
authors.affiliation: Instituto de Pesca, APTA-SAA, São Paulo, SP, Brasil.
authors.forename: R
authors.initials: R
authors.lastname: Knoop
authors.affiliation: Instituto de Pesca, APTA-SAA, São Paulo, SP, Brasil.
authors.forename: D C
authors.initials: DC
authors.lastname: Dias
authors.affiliation: Universidade de São Paulo - USP, Lorena, SP, Brasil.
authors.forename: F M
authors.initials: FM
authors.lastname: França
authors.affiliation: Universidade Estadual de Maringá (UEM), Maringá, PR, Brasil.
authors.forename: A M
authors.initials: AM
authors.lastname: Antonucci
authors.affiliation: Instituto de Pesca, APTA-SAA, São Paulo, SP, Brasil.
authors.forename: P C
authors.initials: PC
authors.lastname: Teixeira
authors.affiliation: Departamento de Reprodução Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo (FMZV-USP), São Paulo, SP, Brasil.
authors.forename: P
authors.initials: P
authors.lastname: Viau
authors.affiliation: Departamento de Reprodução Animal, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo (FMZV-USP), São Paulo, SP, Brasil.
authors.forename: C A
authors.initials: CA
authors.lastname: Oliveira
authors.affiliation: Instituto Biológico, APTA-SAA, São Paulo, SP, Brasil.
authors.forename: M
authors.initials: M
authors.lastname: Hipolito
authors.affiliation: Instituto de Pesca, APTA-SAA, São Paulo, SP, Brasil.
authors.forename: C M
authors.initials: CM
authors.lastname: Ferreira
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000822:Animal Husbandry; D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology*; D004032:Diet / Q000662:veterinary; D019587:Dietary Supplements; D010586:Phagocytes / Q000502:physiology; D010587:Phagocytosis / Q000502:physiology; D011892:Rana catesbeiana / Q000276:immunology*
chemical_list: D001205:Ascorbic Acid
keywords: Lithobates catesbeianus; bullfrog; corticosterone; leucocytes; macrophage activation; vitamin C