Maternal obesity increases insulin resistance, low-grade inflammation and osteochondrosis lesions in foals and yearlings until 18 months of age

PLoS One. 2018 Jan 26;13(1):e0190309. doi: 10.1371/journal.pone.0190309. eCollection 2018.


Introduction: Obesity is a growing concern in horses. The effects of maternal obesity on maternal metabolism and low-grade inflammation during pregnancy, as well as offspring growth, metabolism, low-grade inflammation, testicular maturation and osteochondrotic lesions until 18 months of age were investigated.

Material and methods: Twenty-four mares were used and separated into two groups at insemination according to body condition score (BCS): Normal (N, n = 10, BCS ≤4) and Obese (O, n = 14, BCS ≥4.25). BCS and plasma glucose, insulin, triglyceride, urea, non-esterified fatty acid, serum amyloid A (SAA), leptin and adiponectin concentrations were monitored throughout gestation. At 300 days of gestation, a Frequently Sampled Intravenous Glucose Tolerance Test (FSIGT) was performed. After parturition, foals' weight and size were monitored until 18 months of age with plasma SAA, leptin, adiponectin, triiodothyronine (T3), thyroxine (T4) and cortisol concentrations measured at regular intervals. At 6, 12 and 18 months of age, FSIGT and osteoarticular examinations were performed. Males were gelded at one year and expression of genes involved in testicular maturation analysed by RT-qPCR.

Results: Throughout the experiment, maternal BCS was higher in O versus N mares. During gestation, plasma urea and adiponectin were decreased and SAA and leptin increased in O versus N mares. O mares were also more insulin resistant than N mares with a higher glucose effectiveness. Postnatally, there was no difference in offspring growth between groups. Nevertheless, plasma SAA concentrations were increased in O versus N foals until 6 months, with O foals being consistently more insulin resistant with a higher glucose effectiveness. At 12 months of age, O foals were significantly more affected by osteochondrosis than N foals. All other parameters were not different between groups.

Conclusion: In conclusion, maternal obesity altered metabolism and increased low-grade inflammation in both dams and foals. The risk of developing osteochondrosis at 12 months of age was also higher in foals born to obese dams.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adiponectin / blood
  • Animals
  • Animals, Newborn
  • Blood Glucose / metabolism
  • Female
  • Glucose Tolerance Test
  • Horse Diseases / pathology*
  • Horse Diseases / physiopathology*
  • Horses
  • Inflammation / etiology
  • Inflammation / veterinary*
  • Insulin / blood
  • Insulin Resistance / physiology*
  • Leptin / blood
  • Male
  • Maternal-Fetal Exchange
  • Obesity / complications
  • Obesity / physiopathology
  • Obesity / veterinary*
  • Osteochondrosis / etiology
  • Osteochondrosis / veterinary*
  • Pregnancy
  • Pregnancy Complications / pathology
  • Pregnancy Complications / physiopathology
  • Pregnancy Complications / veterinary*


  • Adiponectin
  • Blood Glucose
  • Insulin
  • Leptin

Grants and funding

This work was funded by grants from the "Institut Français du Cheval et de l’Equitation" and by the "Fonds Eperon" (FOETALIM project). The funders had no role in study design, data collection and analysis, decision to publish, nor preparation of the manuscript.