PHENOTYPIC CONSOLIDATION COEFFICIENTS OF BIRTH-WEIGHT INDICATORS IN SOWS OF WELSH BREED

Abstract

The aim of the research was to study the effect of sow and boar age on average weight of newly born piglets, considering the season of the year and the age of the animals. The studies were conducted in the research farm of SE “Gontarivka”, Volchansky district, Kharkiv region. Natural breeding of sows is used for reproduction on the farm. The insemination of sows was carried out according to the scheme of studies. 35 head of sows and 4 boars of different ages and live weights were selected. Four groups of sows were formed. In order to study the impact of the season of the year on sow productivity, the first series of studies were conducted in the autumn, the second series - in the spring according to the same scheme. In different groups of animals, average weight of newly born piglets ranged from 1.10 to 1.21 kg. The average value of this indicator for all sows for both studied seasons was 1.16 kg. The magnitude (for all sows of the period) in winter farrowing was 1.74 % higher than the summer farrowing (for all sows of the period), although the difference between these groups was not probable. Between the sows of different ages, inseminated by boars of different ages, in winter, the higher values were given to young sows that were inseminated by young boars (p<0.01 compared to young sows that were inseminated by full-grown boars). Among the sows of different ages, inseminated by boars of different ages, in the summer, the highest values were middle-aged, which were inseminated by middle-aged boars (p<0.01 compared to young sows in winter, inseminated by full boars and p<0.05 compared to young sows in summer, which were inseminated by adult boars). During the summer period the middle-aged sows, which were inseminated by middle-aged boars, received maximum values of average weight of newly born piglets, which were higher than sows of other groups by 10.00-0.83 %. The most consolidated high-birth-weight rates were obtained in winter for young sows that were inseminated by adult boars. In the summer, the most consolidated were young sows inseminated by young boars.