Genetic relationship between Neck and Limb defects in Pura Raza Española Horses

Area of Science:

• Equine genetics
• Animal conformation
• Veterinary orthopedics

Background:

• Conformational defects in neck and limb affect Pura Raza Española (PRE) horse functionality.
• The genetic relationship between these defects was previously unexplored.

Purpose of the Study:

• To estimate genetic correlations between two neck defects (Cresty neck, Ewe neck) and twelve limb defects in PRE horses.
• To investigate the hypothesis of a genetic link between neck and limb morphology.

Main Methods:

• Analysis of 56,644 PRE horses from 2012-2023.
• Conformation traits scored using two-class and multi-class scales.
• Estimation of genetic parameters with covariates for age, sex, origin, management, and inbreeding.

Main Results:

• Splay-footed rear limb (SFR) was the most frequent limb defect in horses with neck defects.
• Moderate genetic correlations were found, ranging from -0.25 to 0.51 depending on the defect and scoring approach.

Conclusions:

• The study supports a genetic relationship between neck and limb conformational defects.
• Integrated selection strategies targeting both anatomical regions are recommended for PRE horses.