EXPERIMENTAL RESEARCH STUDIES
Serum amyloid A concentration in healthy periparturient mares and mares with ascending placentitis
Article first published online: 22 FEB 2013
© 2012 EVJ Ltd
Equine Veterinary Journal
Volume 45, Issue 5, pages 619–624, September 2013
How to Cite
Coutinho da Silva, M. A., Canisso, I. F., MacPherson, M. L., Johnson, A. E. M. and Divers, T. J. (2013), Serum amyloid A concentration in healthy periparturient mares and mares with ascending placentitis. Equine Veterinary Journal, 45: 619–624. doi: 10.1111/evj.12034
- Issue published online: 2 AUG 2013
- Article first published online: 22 FEB 2013
- Accepted manuscript online: 20 DEC 2012 10:30AM EST
- Manuscript Accepted: 7 DEC 2012
- Manuscript Received: 9 JUL 2012
- acute phase proteins;
- placental health;
- serum amyloid A
Reasons for performing study
Placentitis is a prevalent cause of abortion, premature delivery and neonatal death in mares. Early diagnosis is paramount for the survival of the fetus and delivery of a live foal.
To determine: 1) Serum amyloid A (SAA) profile in healthy mares during late gestation; 2) if placentitis affects SAA concentrations and 3) the effects of therapy on SAA concentrations and pregnancy outcome in mares with placentitis.
In Experiment I, 15 healthy pregnant mares were evaluated from 280 days of gestation to 60 h post partum. In Experiment II, pregnant mares were inoculated intra-cervically with Streptococcus zooepidemicus (Day 280–295) and assigned to control (n = 5) and treatment (n = 9) groups. Treatment was initiated at the onset of clinical signs. Serum amyloid A concentrations were determined prior to inoculation and then weekly until abortion or delivery.
Serum amyloid A remained at low concentrations (95% confidence interval [CI]: 3.2–8.1 mg/l) during late gestation followed by a significant increase within 36 h post partum; SAA returned to basal concentrations by 60 h post partum. In Experiment II, SAA significantly increased within 96 ± 56 h of inoculation in control mares followed by abortion. Therapy was effective (P<0.05) in preventing the rise in SAA in 66% (6/9) of mares and only one out of 3 mares with increased SAA aborted. Overall, the incidence of abortion was higher in mares with increased SAA concentrations (75%; 6/8) compared with mares in which SAA remained at baseline concentrations (0/6).
Mares with placentitis had significant increased SAA within 96 h post inoculation and concentrations remained increased until abortion in untreated mares. Successful treatment either prevented the rise of SAA concentration or decreased its concentration to baseline concentrations, followed by delivery of a live foal.
Serum amyloid A may be used as a prognostic indicator in cases of ascending placentitis in the mare.