Evaluation of two GnRH-I based vaccine formulations on the testes function of entire suffolk cross ram lambs

E.R. Earl, M.M. Waterston, E. Aughey, M.J. Harvey, C. Matschke, A. Colston, V.A. Ferro

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26 Citations (Scopus)


A modified GnRH peptide (CHWSYGLRPG-NH2) was conjugated to tetanus toxoid (TT) or diphtheria toxoid (DT) and formulated with Quil A saponin or a sustained release injectible PLGA (poly(lactide-co-glycolide)/triacetin). For the Quil A formulations, two administrations of TT conjugate at 3-weekly intervals were followed by two booster injections with the DT conjugate in entire ram lambs. With the PLGA formulations, only two injections were administered; the first containing TT and the second DT at 6-weekly intervals. Evaluation was carried out by comparing the specific antibody levels produced in relationship to hormone profiles and testicular changes. The Quil A formulation was considered the most effective, as it caused significant reduction in testosterone and follicle stimulating hormone levels, resulting in marked suppression of spermatogenesis.

Original languageEnglish
Pages (from-to)3172-3183
Number of pages12
Issue number16
Early online date2 Feb 2006
Publication statusPublished - 12 Apr 2006


  • GnRH
  • vaccine
  • anti-fertility

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