title: Antimicrobial peptide CAP18 and its effect on Yersinia ruckeri infections in rainbow trout Oncorhynchus mykiss (Walbaum): comparing administration by injection and oral routes.
abstract: The antimicrobial peptide CAP18 has been demonstrated to have a strong in vitro bactericidal effect on Yersinia ruckeri, but its activity in vivo has not been described. In this work, we investigated whether CAP18 protects rainbow trout Oncorhynchus mykiss (Walbaum) against enteric red mouth disease caused by this pathogen either following i.p. injection or by oral administration (in feed). It was found that injection of CAP18 into juvenile rainbow trout before exposure to Y. ruckeri was associated with lowered mortality compared to non-medicated fish although it was less effective than the conventional antibiotic oxolinic acid. Oral administration of CAP18 to trout did not prevent infection. The proteolytic effect of secretions on the peptide CAP18 in the fish gastrointestinal tract is suggested to account for the inferior effect of oral administration.
authors.affiliation: Faculty of Health and Medical Sciences, Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg C, Denmark.
authors.forename: J K
authors.initials: JK
authors.lastname: Chettri
authors.affiliation: Faculty of Health and Medical Sciences, Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg C, Denmark.
authors.forename: F
authors.initials: F
authors.lastname: Mehrdana
authors.affiliation: National Food Institute, Technical University of Denmark, Søborg, Denmark.
authors.forename: E B
authors.initials: EB
authors.lastname: Hansen
authors.affiliation: National Food Institute, Technical University of Denmark, Lyngby, Denmark.
authors.forename: A
authors.initials: A
authors.lastname: Ebbensgaard
authors.affiliation: Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark.
authors.forename: M T
authors.initials: MT
authors.lastname: Overgaard
authors.affiliation: BioMar A/S, Mylius Erichsensvej 35, Brande, Denmark.
authors.forename: A H
authors.initials: AH
authors.lastname: Lauritsen
authors.affiliation: National Veterinary Institute, Technical University of Denmark, Copenhagen, Denmark.
authors.forename: I
authors.initials: I
authors.lastname: Dalsgaard
authors.affiliation: Faculty of Health and Medical Sciences, Department of Veterinary Disease Biology, University of Copenhagen, Frederiksberg C, Denmark.
authors.forename: K
authors.initials: K
authors.lastname: Buchmann
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000494:pharmacology*; D023181:Antimicrobial Cationic Peptides / Q000008:administration & dosage / Q000494:pharmacology*; D005393:Fish Diseases / Q000382:microbiology / Q000517:prevention & control*; D007274:Injections, Intraperitoneal / Q000662:veterinary; D017686:Oncorhynchus mykiss; D014611:Vaccination / Q000662:veterinary*; D015009:Yersinia Infections / Q000382:microbiology / Q000517:prevention & control / Q000662:veterinary*; D044124:Yersinia ruckeri / Q000187:drug effects*; D054804:Cathelicidins
chemical_list: D000890:Anti-Infective Agents; D023181:Antimicrobial Cationic Peptides; D054804:Cathelicidins
keywords: 
  Yersinia ruckeri
  ; CAP18; antimicrobial peptide; rainbow trout