Genetic Parameters and Inbreeding Effect of Morphological Traits in Sardinian Anglo Arab Horse

Abstract

The purpose of this study was to estimate the heritability and genetic correlations of four biometric measurements and an overall score (OS) in the Sardinian Anglo-Arab horse (SAA); moreover, the effect of inbreeding on these traits was investigated. A dataset with 43,624 horses (27,052 females and 16,572 males) was provided by the Agricultural Research Agency of Sardinia (AGRIS). Cannon bone circumference (BC), chest girth (CG), shoulder length (SL), and withers height (WH) were measured on 6033 SAA horses born in Sardinia between 1967 and 2005; beside the measurements, an overall score (OS) was taken comparing the morphology of each horse to an “ideal type” that is scored out of 100. The mean value is 20.5 cm for BC, 185.9 cm for CG, 67.6 cm for SL, 160.8 cm for WH, and 73.2 for the OS. The heritability estimates ranged from 0.78 to 0.23. The results allow to foresee high genetic progress through the breeding programs. The most affected trait by the inbreeding rate seems to only be the withers height.

Genetic Variability and Population Structure in the Sardinian Anglo-Arab Horse

“…In 1874, the Ozieri Army Remount Station was established to supply mounts for the cavalry units of the Italian Army. Indigenous Sardinian mares were crossed with oriental-bred stallions to produce resistant and fast horses that were suitable for the cavalry [ 3 , 4 ].…”

“…In the early 1900s, Captain Grattarola, the commander of the Ozieri Remount Station, continued the work by crossing the best available indigenous mares with Purosangue Orientale stallions which had been purchased directly from Bedouin tribes. Later on, Arab and Thoroughbred stallions started to be bred with the mares of mixed Sardinian and oriental ancestry [ 4 ].…”

“…In 1967, when the studbook of this breed was officially established, blood percentages were defined and accurately settled. The breed was officially named “Sardinian Anglo-Arab,” and it was described as, “The product of the selection and crossbreeding between Arabian lines, Thoroughbred, Anglo-Arab Thoroughbred, Sardinian Anglo-Arab stallions and indigenous mares with a percentage of Arabian blood not less than 25% and not more than 75%.” From that moment, the main breeding goal became sport [ 4 , 5 ].…”

A Genetic Window on Sardinian Native Horse Breeds through Uniparental Molecular Systems

“…The Sardinian Anglo-Arab breed is the result of selected crossbreeding between indigenous Sardinian mares carrying Arabian blood and Thoroughbred and Arab stallions [2,3]. It is considered an endangered horse breed currently counting 3005 animals (2871 females and 134 males) (FAO 2018; last update: September 2019).…”

Elo Method and Race Traits: A New Integrated System for Sport Horse Genetic Evaluation

“…In the equestrian competitions, the SAA horses also compete against horses of other breeds; there are no specific events only for SAA in jumping or endurance. SAA mares are frequently crossbred with European warmbloods to obtain more competitive horses in jumping, or with Arabian stallions, to obtain more competitive horses in endurance [ 3 ].…”