Discriminant Canonical Analysis of the Contribution of Spanish and Arabian Purebred Horses to the Genetic Diversity and Population Structure of Hispano-Arabian Horses

Abstract

Genetic diversity and population structure were analyzed using the historical and current pedigree information of the Arabian (PRá), Spanish Purebred (PRE), and Hispano-Arabian (Há) horse breeds. Genetic diversity parameters were computed and a canonical discriminant analysis was used to determine the contributions of ancestor breeds to the genetic diversity of the Há horse. Pedigree records were available for 207,100 animals born between 1884 and 2019. Nei’s distances and the equivalent subpopulations number indicated the existence of a highly structured, integrated population for the Há breed, which is more closely genetically related to PRá than PRE horses. An increase in the length of the generation interval might be an effective solution to reduce the increase in inbreeding found in the studied breeds (8.44%, 8.50%, and 2.89%, for PRá, PRE, and Há, respectively). Wright’s fixation statistics indicated slight interherd inbreeding. Pedigree completeness suggested genetic parameters were highly reliable. High GCI levels found for number of founders and non-founders and their relationship to the evolution of inbreeding permit controlling potential deleterious negative effects from excessively frequent mating between interrelated individuals. For instance, the use of individuals presenting high GCI may balance founders’ gene contributions and consequently preserve genetic diversity levels (current genetic diversity loss in PRá, PRE, and Há is 6%, 7%, and 4%, respectively).

A Survey of Horse Selection, Longevity, and Retirement in Equine-Assisted Services in the United States

“…A significant ( p < 0.0001) Pillai’s Trace value (1.20) indicated there were detectable differences across the classification groups. Canonical variable 1 had the greatest squared canonical correlation at 0.30 which is below the suggested cutoff value of 0.4 [ 15 ]. Canonical variable 1 explained 29% of variance with an Eigenvalue of 0.45.…”

Variability of Meat and Carcass Quality from Worldwide Native Chicken Breeds

“…In this way, noise or redundancy problems in the variables used were detected before data manipulation. The exclusion of unnecessary variables through multicollinearity analysis ensures that redundancies do not overinflate the variance explanatory potential [ 132 ]. The variance inflation factor (VIF) is used as a multicollinearity indicator, and it can be calculated by the use of the following formula: VIF = 1/(1 − R 2 ), where R 2 is the coefficient of determination of the regression equation.…”

One Hundred Years of Coat Colour Influences on Genetic Diversity in the Process of Development of a Composite Horse Breed

“…Coat colour genetic control may be compulsorily considered in the breeding programmes of horse breeds with fixed standards [12]. Contextually, although no explicit mention of coat colour is made in the Há breed standard [13], multiple conditioning factors (breeder preferences among others), may have shaped its population structure and genetic diversification process, and also those occurring in its two ancestral breeds [14,15].…”