Lateral profile of the pigs' teat line of different Ukrainian breeds

Abstract

A quantitative analysis of the lateral profiles of five Ukrainian pig breeds (n=584), listed in the State Books of Pedigree Animals, showed that the teat line's complete symmetry was found only in the Poltava meat breed. The large black one is characterized by insignificant (6%) asymmetry, and among species of the Ukrainian meat breed, Ukrainian spotted steppe and Mirgorod breeds of asymmetry cases were noted on average 20-30%. The analysis revealed that the structure of the pigs' teat line with asymmetry is characterized by dominant-enantiomorphic proportional structuring, which ensures the population stability of breeds in the changing environment. We established that the teat line's left-dominant structure prevails both in boars and in sows of different breeds in the case of dominance inversion that demonstrates the ability for evolutionary adaptation self-organization of multi-component living systems under environmental factors. The evolutionary hypothesis's conclusions, which consider lateralization as a natural evolutionary process, an adaptive specialization of bilaterally arranged organisms, have been confirmed. There was assumed the possibility of improving selection in pig breeding by increasing the effect of heterosis in selecting couple pairs with laterally differentiated teat lines.