Description of outcomes of experimental infection with feline haemoplasmas: copy numbers, haematology, Coombs' testing and blood glucose concentrations

Vet Microbiol. 2009 Nov 18;139(3-4):323-32. doi: 10.1016/j.vetmic.2009.06.028. Epub 2009 Jun 21.


The aim of this study was to compare blood copy, haematological and glucose values between cats experimentally infected with either Mycoplasma haemofelis (Group HF: 10 cats), 'Candidatus M. haemominutum' (Group HM: 3 cats) or 'Candidatus M. turicensis' (Group TU: 3 cats). Blood samples were collected regularly up to 85 days post-infection (DPI) for haemoplasma real-time quantitative PCR, haematology, Coombs' testing and blood glucose measurement. Statistical analysis was performed using a general linear model (ANOVA) appropriate for a repeated measures experiment with significance set as P<0.05. Cats in Group TU had significantly lower blood copy numbers than cats in Group HF (P<0.001) and HM (P<0.001). All Group HF cats developed anaemia (often severe), macrocytosis and evidence of erythrocyte-bound antibodies whereas Groups HM and TU cats did not. Group HF had significantly lower PCVs, haemoglobin concentrations and red blood cell counts, and significantly higher mean cell volumes, than Groups HM and TU. In Group HF, erythrocyte-bound antibodies reactive at 4 degrees C (both IgM and IgG) appeared between 8 and 22 DPI and persisted for two to four weeks, whereas those reactive at 37 degrees C (primarily IgG) appeared between 22 and 29 DPI and persisted for one to five weeks. In most cats antibodies appeared after the fall in haemoglobin started. Although Group TU had significantly lower glucose concentrations than Groups HF (P=0.006) and HM (P=0.027), mean blood glucose concentrations remained within the reference range in all groups. This study demonstrates that M. haemofelis infection, in contrast to 'Candidatus M. haemominutum' and 'Candidatus M. turicensis' infection, can result in a severe macrocytic anaemia and the development of cold and warm reactive erythrocyte-bound antibodies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anemia, Macrocytic / drug therapy
  • Anemia, Macrocytic / microbiology
  • Animals
  • Anti-Bacterial Agents / therapeutic use
  • Blood / microbiology
  • Blood Glucose / analysis
  • Cat Diseases / blood
  • Cat Diseases / drug therapy
  • Cat Diseases / microbiology*
  • Cat Diseases / physiopathology
  • Cats
  • Coombs Test
  • DNA, Bacterial / blood
  • DNA, Bacterial / genetics
  • Mycoplasma Infections / blood
  • Mycoplasma Infections / microbiology
  • Mycoplasma Infections / physiopathology
  • Mycoplasma Infections / veterinary*
  • Mycoplasma*
  • Polymerase Chain Reaction / veterinary
  • Species Specificity
  • Specific Pathogen-Free Organisms


  • Anti-Bacterial Agents
  • Blood Glucose
  • DNA, Bacterial