Ultrasonographic Evaluation of Morphological Characteristics and Volume of the Normal Thyroid Gland in Turkmen Horses and Its Association with Biochemical Parameters

Document Type : Original Article

Authors

1 Department of veterinary Clinical Sciences, SR.C., Islamic Azad University, Tehran, Iran

2 Epidemiology and Zoonosis Division, Department of Food Hygiene, Faculty of Veterinary medicine, University of Tehran, Tehran, Iran

10.22075/jvlr.2026.39705.1195

Abstract

This study investigated the effects of age, sex, and body weight on thyroid gland dimensions and serum biochemical parameters in Turkmen horses.
Twenty-eight horses were categorized by age (<36 months vs. ≥36 months) and sex. Univariate ANCOVA models were used to examine effects on thyroid dimensions and serum parameters, with weight as a covariate.
For thyroid dimensions, sex significantly influenced length and volume of right and left lobes, with mares having larger dimensions. However, low adjusted R² values (0.013-0.211) suggested model over fitting due to small sample size. For biochemical parameters, weight significantly predicted TG, cholesterol, ALP, T4, and T3 (P<0.05). Age significantly affected ALT (P=0.005), and sex significantly affected ALP (P=0.040), with higher adjusted R² values (0.556-0.796) indicating more reliable models.
While sex may influence thyroid morphology in horses, these findings are preliminary due to overfitting. Biochemical parameters showed more robust associations with weight, age, and sex. Larger studies are needed to confirm these observations.

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References

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