title: Cinnamon (Cinnamomum sp.) inclusion in diets for Nile tilapia submitted to acute hypoxic stress.
abstract: The aim of this study was to evaluate the possible effects of diets supplemented with probiotics and different cinnamon levels (powder and essential oil) on immunological parameters of Nile tilapia after being subjected to acute stress by hypoxia. Three hundred and thirty juvenile male tilapia fish (66.08 ± 2.79 g) were distributed in 30 tanks of 100 L capacity (11/cage) with a water recirculation system. The animals were fed for 71 days with diets containing extruded cinnamon powder at different levels (0.5, 1, 1.5, 2%), cinnamon essential oil (0.05, 0.1, 0.15; 0.2%) and probiotics (0.4%), all in triplicate. At the end of the experiment, the fish (200.36 ± 19.88 g) of the different groups were subjected to stress by hypoxia. Hypoxia was achieved by capturing the animals with a net, keeping them out of the water for three minutes, and then sampling the blood 30 min after the procedure to determine the levels of cortisol, glucose, haematocrit, lysozyme, bactericidal index, total protein, and its fractions. The animals kept blood homeostasis after hypoxic stress. Diet supplementation with 0.5% cinnamon powder improved the fish immune response, since it resulted in an increase of 0.5% in γ-globulin level. Administration of 0.15% cinnamon essential oil resulted in an increase of α1 and α2-globulins, which may be reflected in increased lipid content of the carcass and the hepatosomatic index. More studies are necessary to better understand the effects of these additives for fish immunity.
authors.affiliation: Laboratório de Aquacultura, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil. Electronic address: welliene@yahoo.com.br.
authors.forename: Welliene
authors.initials: W
authors.lastname: M Dos Santos
authors.affiliation: Laboratório de Aquacultura, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Túlio
authors.initials: T
authors.lastname: S de Brito
authors.affiliation: Laboratório de Aquacultura, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Samuel
authors.initials: S
authors.lastname: de A Prado
authors.affiliation: Laboratório de Aquacultura, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Camila
authors.initials: C
authors.lastname: G de Oliveira
authors.affiliation: Laboratório de Aquacultura, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Andréia
authors.initials: A
authors.lastname: C De Paula
authors.affiliation: Laboratório de Aquacultura, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Daniela
authors.initials: D
authors.lastname: C de Melo
authors.affiliation: Laboratório de Aquacultura, Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Paula
authors.initials: P
authors.lastname: A P Ribeiro
mesh_terms: D000693:Anaerobiosis / Q000502:physiology; D000821:Animal Feed / Q000032:analysis; D000818:Animals; D023681:Cichlids / Q000502:physiology*; D002935:Cinnamomum zeylanicum; D004032:Diet / Q000662:veterinary*; D019587:Dietary Supplements; D008297:Male; D009822:Oils, Volatile; D011208:Powders; D019936:Probiotics; D013312:Stress, Physiological / Q000502:physiology*
chemical_list: D009822:Oils, Volatile; D011208:Powders
keywords: Haematology; Immunostimulants; Plant extracts; Protein fractionation