Pilot study to evaluate the effect of oral supplementation of Enterococcus faecium SF68 on cats with latent feline herpesvirus 1

J Feline Med Surg. 2009 Aug;11(8):650-4. doi: 10.1016/j.jfms.2008.12.006. Epub 2009 Feb 6.


Feline herpesvirus 1 (FHV-1) infection is extremely common in cats and is frequently associated with morbidity because of recurrent ocular and respiratory clinical signs of disease. Enterococcus faecium strain SF68 is an immune-enhancing probiotic used as a dietary supplement. In this pilot study, 12 cats with chronic FHV-1 infection were administered either SF68 or a placebo, monitored for clinical signs of disease, monitored for FHV-1 shedding, and evaluated for FHV-1 specific humoral and cell-mediated immune responses and fecal microbiome stability. Fecal microbial diversity was maintained throughout the study in cats supplemented with SF68, but decreased in cats fed the placebo, indicating a more stable microbiome in cats fed SF68. While clinical results varied among individual cats, the overall findings suggest that administration of the probiotic lessened morbidity associated with chronic FHV-1 infection in some cats. Additional study is warranted to determine efficacy in a clinical setting.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Analysis of Variance
  • Animals
  • Cat Diseases / diet therapy*
  • Cats
  • Conjunctivitis, Viral / diet therapy
  • Conjunctivitis, Viral / veterinary*
  • Electrophoresis / veterinary
  • Enterococcus faecium*
  • Feces / virology
  • Female
  • Herpesviridae / immunology*
  • Herpesviridae Infections / diet therapy
  • Herpesviridae Infections / veterinary*
  • Male
  • Pilot Projects
  • Polymerase Chain Reaction / veterinary
  • Probiotics / administration & dosage*
  • Specific Pathogen-Free Organisms