This study aimed to examine the seasonal dynamics of non-structural carbohydrates in pasture and their relationship to metabolic indicators in horses with a history of laminitis. Thirty Hucul mares were divided into a laminitis group (LG, n = 15) and a control group (CG, n = 15). Insulin, glucose, fructosamines concentrations and body weight were monitored during four sampling periods (S0–S3), while pasture variables were analyzed during three periods (S1–S3). The concentration of water-soluble carbohydrates was highest in May (126.8 g/kg DM) and measured lower in October (57.9 g/kg DM), while starch concentrations measured 0.1 g/kg DM in May, 25.8 g/kg DM in July, and 24.0 g/kg DM in October. No significant differences were observed in insulin concentrations between groups (p > 0.05). Glucose was significantly higher in LG in May (LG: 5.50 mmol/L; CG: 5.09 mmol/L; p < 0.05) and October (LG: 5.98 mmol/L; CG: 5.24 mmol/L; p < 0.01). Fructosamine values were higher in LG throughout the season, with significance in October (LG: 120.6 μmol/L; CG: 101.1 μmol/L; p < 0.05). Body weight increased in both LG and CG during grazing (S2), with mean values at S0 being 423.6 kg in LG and 424.8 kg in CG, and at S2 being 533.8 kg in LG and 535.6 kg in CG (p > 0.05 for between-group differences). These findings suggest a different glycemic response in laminitic horses in relation to WSC and starch concentrations and highlight starch as a potential predictor of glycemic instability.

Equine obesity currently represents aďż˝significant welfare concern, with its development influenced byďż˝seasonal changes inďż˝the nutritional value ofďż˝pasture, which substantially affect the animals’ energy balance. The aim ofďż˝this study was...

The aim of this study was to compare within-horse changes and between-horse differences in selected metabolic parameters in twenty draft mares, of which ten belonged to a group with a history of laminitis (LG) and ten formed the control group (CG). Measurements were conducted during four seasonal sampling periods in March (S0), May (S1), July (S2), and September (S3). Within-horse variability across the season was quantified using the coefficient of variation (CV), while differences between groups were evaluated using the t-test or the Mann–Whitney test depending on data distribution. Mares in the LG group exhibited significantly higher insulin variability compared to the CG (20.06% vs. 7.52%; p = 0.023), whereas no statistically significant differences were found for glucose (p = 0.279). Between-horse variability within individual sampling periods was analyzed using the F-test. In S0, no differences were found for glucose (p = 0.607) or insulin (p = 0.980). In S1, higher variability in the LG group was observed for insulin (p = 0.0329), while glucose did not differ between groups (p = 0.952). In S2, the LG group showed markedly higher variability for both glucose (p < 0.0001) and insulin (p = 0.0007). In S3, no differences were found for glucose (p = 0.512) or insulin (p = 0.872). Overall, mares with a history of laminitis exhibited greater seasonal fluctuations and, in some periods, higher inter-individual variability in glucose and insulin concentrations, suggesting lower metabolic stability in response to seasonal environmental conditions.