Gender differences in bone turnover in 2-year-old Thoroughbreds

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journal

21 Scopus Citations
View graph of relations


  • B. F. Jackson
  • C. Lonnell
  • K. Verheyen
  • J. L N Wood
  • J. S. Price


Original languageEnglish
Pages (from-to)702-706
Journal / PublicationEquine Veterinary Journal
Issue number7
Publication statusPublished - Nov 2003
Externally publishedYes


Reasons for performing study: Injuries to the skeleton are a major cause of morbidity and mortality in racehorses and age, gender and season have all been shown to influence risk of injury. Objectives: To use biochemical markers of bone cell activity to establish to whether cellular processes in bone underlie these described effects. Methods: Blood samples were collected monthly from 2-year-old horses in race training between November 1998 and September 1999. Mean age at the start of the study was 20 months (range 18-23 months), with no significant difference in average age between colts (n = 84) and fillies (n = 63). Three markers were measured; osteocalcin (OC, bone formation), the carboxyterminal cross-linked telopeptide of type I collagen (ICTP, bone resorption) and the carboxyterminal propeptide of type I collagen (PICP), which is less 'bone-specific' than the other 2 markers. Results: Colts had, on average, 3.62 ng/ml higher OC concentrations (P = 0.044) and 0.68 mg/l higher ICTP concentrations (P = 0.01) than fillies. The effect of gender was not statistically significant for PICP. However, in May, PICP concentrations were on average 157 mg/l higher in fillies than colts. There was no effect of age or season on marker concentrations. Conclusions: This study has shown that there are gender differences in bone turnover markers in 2-year-old Thoroughbreds; however, age, within the limited range studied, did not have a significant effect on bone cell activity. Lower bone marker concentrations may reflect smaller bone size and/or earlier skeletal maturation in fillies. An increase in concentrations of PICP in fillies in spring and early summer may relect an influence of sex hormones on collagen turnover. Potential relevance: Gender differences in bone cell activity in 2-year-old colts and fillies may influence bone's adaptive responses to training and risk of injury.

Research Area(s)

  • Bone, Gender, Horse, ICTP, Marker, Osteocalcin, PICP

Citation Format(s)

Gender differences in bone turnover in 2-year-old Thoroughbreds. / Jackson, B. F.; Lonnell, C.; Verheyen, K.; Wood, J. L N; Pfeiffer, D. U.; Price, J. S.

In: Equine Veterinary Journal, Vol. 35, No. 7, 11.2003, p. 702-706.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journal