title: Effects of a homeopathic complex on the performance and cortisol levels in Nile tilapia (Oreochromis niloticus).
abstract: BACKGROUND
  Intensive fish farming results in stress adversely effecting the performance of farmed fish. Plasma cortisol is a validated measure of stress in fish. We evaluated the effect of a homeopathic complex on the cortisol level of Nile tilapias (Oreochromis niloticus).
  
  
  METHODS
  60 animals with approximate average weight of 100 g each at the start of experiment were randomly distributed in six glass fiber water tanks, capacity 1000 liters, with a daily water renewal rate of 20%. They received one of two treatments: 30 animals in control treatment and 30 animals receiving the homeopathic complex Homeopatila 100. On days 1, 30 and 60, all fish were anesthetized and blood was collected by puncture on the caudal vein, to determine the levels of circulating cortisol.
  
  
  RESULTS
  At the end of the experiment the fish receiving a homeopathic complex, had significantly lower circulating cortisol level (17.96 ng/mL ± 0.95) than the control group (38.68 ng/mL ± 1.21) (p < 0.05).
  
  
  CONCLUSIONS
  Cortisol levels were significantly lower in the treated group than control, and the fish were larger in the treated group.
authors.affiliation: Universidade Paranaense, Umuarama, PR, Brazil.
authors.forename: Luiz Sérgio
authors.initials: LS
authors.lastname: Merlini
authors.affiliation: Universidade Estadual de Maringá, Maringá, PR, Brazil.
authors.forename: Lauro
authors.initials: L
authors.lastname: Vargas
authors.affiliation: Universidade Paranaense, Umuarama, PR, Brazil. Electronic address: piau@unipar.br.
authors.forename: Ranulfo
authors.initials: R
authors.lastname: Piau
authors.affiliation: Universidade Estadual de Maringá, Maringá, PR, Brazil.
authors.forename: Ricardo Pereira
authors.initials: RP
authors.lastname: Ribeiro
authors.affiliation: Universidade Estadual Paulista Júlio de Mesquita Filho, UNESP, Botucatu, SP, Brazil.
authors.forename: Natalie Bertelis
authors.initials: NB
authors.lastname: Merlini
mesh_terms: D000818:Animals; D023681:Cichlids / Q000097:blood / Q000502:physiology*; D006705:Homeopathy / Q000379:methods*; D006854:Hydrocortisone / Q000097:blood*; D008419:Materia Medica / Q000494:pharmacology*; D013312:Stress, Physiological / Q000187:drug effects*
chemical_list: D008419:Materia Medica; D006854:Hydrocortisone
keywords: Cortisol; Homeopathy; Nile Tilapia (Oreochromis niloticus); Stress