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farriery
veterinary
biomechanics
nutrition
anatomy
2022
Cohort Study

Successful Pregnancy Outcome in Mares: The Potential Role of Body Conditional Score, Age and Biochemical Parameter's Adjustments.

Authors: Satué Katiuska, Fazio Esterina, Muñoz Ana, Medica Pietro

Journal: Journal of equine veterinary science

Summary

# Editorial Summary Maintaining optimal body condition and metabolic health during pregnancy is crucial for mare welfare and foal viability, yet the biochemical changes that accompany gestation remain incompletely characterised across different mare populations. This Spanish study tracked 45 broodmares across three groups—older mares in poor condition (14–18 years, BCS <4/10), younger mares in moderate condition (4–8 years, BCS 5–6/10), and middle-aged obese mares (6–11 years, BCS 8/10)—measuring 15 plasma biochemical parameters monthly throughout pregnancy. All pregnant mares exhibited physiologically expected hyperlipidaemia with elevated triglycerides and bilirubin (direct, indirect and total) across all three trimesters, reflecting the metabolic demands of gestation; however, advanced maternal age was associated with additional biochemical abnormalities suggesting compromised hepatic and renal function, whereas obesity paradoxically did not exacerbate lipidic dysmetabolism. For practitioners managing breeding programmes, these findings reinforce that whilst some biochemical shifts during pregnancy are normal adaptive responses, ageing mares warrant closer monitoring of liver and kidney markers, and that condition scoring and age should inform veterinary surveillance protocols more robustly than weight alone—particularly as older, thin mares showed the most pronounced metabolic stress.

Read the full abstract on PubMed

Practical Takeaways

  • Monitor older broodmares (>14 years) more closely during pregnancy due to age-related biochemical changes and potential organ function decline
  • Expect physiological hyperlipidemia and elevated bilirubin as normal adaptations to pregnancy in mares—these are not necessarily pathological signs requiring intervention
  • Body condition management during pregnancy should focus on maintaining optimal BCS (5-6/10) rather than over-conditioning, as obesity alone does not protect against metabolic changes

Key Findings

  • Pregnancy in Spanish broodmares induced hyperlipidemia with hypertriglyceridemia and increased plasma bilirubin concentrations (P < 0.05)
  • Older pregnant mares (14-18 years) showed biochemical changes consistent with decreased organ functionality compared to younger mares (P < 0.05)
  • Obesity (BCS 8/10) did not significantly influence lipidic metabolism during pregnancy (P > 0.05)
  • Biochemical changes were monitored across three pregnancy periods with monthly blood sampling throughout gestation

Conditions Studied

pregnancyhyperlipidemiahypertriglyceridemiahyperbilirubinemia

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