Exterior features of American miniature horses of the pony farm "Idalgo"

Abstract

The main task of preserving populations of small breeds of horses imported from abroad with their unique characteristic features of the exterior and type of constitution is the organization of the reproduction of the livestock and the preservation of the exterior parameters of the breed in descendants. In modern conditions of a small number of populations of such breeds, the influence of the inbreeding depression factor increases, as well as the manifestation of recessive mutations and hereditary pathologies in the offspring.[8] On the one hand, this can form changes that are not typical for the breed: phenotype, measurements, body type of the animal's format; on the other hand, such features of breeding horses in the absence of a selection press and selection will lead to the formation of a population of horses of the breed type. Such breed types should be fixed by breed leaders and have a territorial localization; if this does not happen, then the livestock that does not meet the requirements of the breed may lose the status of purebred. [2][6] The study consisted in monitoring the indicators of measurements by generation to identify the dynamics of changes in the format of the horse population and their compliance with the breed standard of American miniature pony horses. The article presents the indicators of the main measurements of American miniature pony horses for a number of generations and carried out their comparative analysis, with the standard requirements of the corresponding measurements of the breed. The analysis showed the following dynamics: in height at the withers, the increase is 46.5%, in the oblique length of the body, the increase is 97.8%, in the distance from the withers to the tail, the increase was 103.5%, which characterizes a more intensive growth of the peripheral skeleton in the postembryonic period and the formation of an elongated format with age . While the angle of the shoulder, wrist and tarsus is less variable in the age aspect and depends on individual hereditary factors, and not on age. A number of recommendations have been developed for specialists of the club "IDALGO" on the selection of parental pairs for correction for compliance with the standard requirements for measuring indicators in offspring.