Fish Physiology and Biochemistry

, Volume 16, Issue 1, pp 11–18 | Cite as

Young of the Midas cichlid get biologically active nonnutrients by eating mucus from the surface of their parents

  • M. Schütz
  • G. W. Barlow


Fry (first mobile offspring) of the Midas cichlid,Cichlasoma citrinellum, feed on the epidermal mucus of their parents. Ingesting mucus increased at first then fluctuated during the four-week period of parental care of swimming young (fry). Total protein in the mucus was assessed using Bio-Rad-Protein-assays. Western blots revealed prolactin (tiPRL 177 and traces of tiPRL 188) and growth hormone (tiGH). Thyroxine (T4) was also detected quantitatively by RIA. Fry with parents grew faster initially than those raised without. The growth rate of fry isolated from parents increased, however, when fed daily about 0.01 mg ovine PRL or ovine GH.


thyroxine prolactin growth hormone parental care epidermal mucus development fry parenting parentophagy 


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Copyright information

© Kugler Publications 1997

Authors and Affiliations

  • M. Schütz
    • 1
  • G. W. Barlow
    • 1
  1. 1.Department of Integrative BiologyUniversity of CaliforniaBerkeleyUSA

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