The Influence of the Size, Age and Sex on the Computed Tomographic Measured Size of the Pituitary Gland in Normal Horses.

This research article investigates the extent to which a horse’s size, age, and sex influence the size of its pituitary gland, proposing the use of a Pituitary gland to Brain area ratio for comparing different horses.

Methods

• The study involved thirty-two horses identified to be free from pituitary pars inter-media dysfunction, what might be commonly known as a functional disorder of the pituitary gland.
• These horses underwent a contrast-enhanced computed tomographic (CT) examination, a diagnostic imaging procedure that allows detailed visualization of the body’s internal structures.
• The researchers used the CT images to measure the height of the pituitary gland and compute the Pituitary height-to-Brain area ratio (P:B ratio).

Statistical Analysis and Results

• The researchers then correlated the measurements from the images (Pituitary gland height and P:B ratio) with the horse’s size, age, and sex.
• The analysis showed a strong correlation between the pituitary gland’s height and the size (P < 0.001) and age (P < 0.001) of the horses – indicating that as the horse's size and age increase so does the size of the pituitary gland. However, there was no significant correlation between the pituitary gland's height and the horse's sex (P = 0.40).
• When considering the P:B ratio, there was no significant association with the horse’s size (P = 0.25), age (P = 0.06), or sex (P = 0.25), demonstrating that this metric remains consistent across varying horse sizes, ages, and genders.

Conclusion

• The size of the pituitary gland in horses varies according to their size and age. However, the sex of the horse doesn’t have a significant impact on the size of the pituitary gland.
• The researchers propose the P:B ratio as a useful tool for comparing pituitary gland sizes of different horses as it is not significantly influenced by the size, age or sex of the horse.