Coefficients of Welsh sows multiplicity phenotypic consolidation

The aim of the research, the results of which are presented in the article, was to study the effect of sows and boars age on their multiplicity, taking into account the season of the year and the age of the animals. The studies were conducted in the research farm of SE “Gontarivka” of the Volchansky district of Kharkiv region. Natural breeding of sows is used for reproduce 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 uterus 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. The same animals used in both series of studies. For different animal groups, multiplicity ranged from 10.56 to 11.78 heads. The best group (uterus at 18 months of age in winter farrowing) outperformed the inferiority group of the worse group (uterus at the age of 24 months in summer farrowing) by 11.55% (p <0.05). At the same time, in summer the values of multiplicity (11.26 ± 0.189 piglets per uterus) were obtained by 1.81%, compared to winter piglets (11.06 ± 0.189 piglets per uterus), although the difference was not probable. Within the individual series of studies, the best values of multiplicity were obtained by using age boars (48 months), although the differences were also not significant. Possible differences were found between young uterus (18 months) inseminated by adult boars (48 months) in summer farrowing and young uterus (18 months) inseminated by young boars (18 months) in winter farrowing. These differences were at the level of 4.68% (p <0.05). The relatively consolidated multiplicity index (to determine phenotypic consolidation coefficients in both ways) was obtained in only one group of animals - middle-aged sows (24 months) for insemination by middle-aged boars (24 months) during summer farrowing. The least consolidated (by determining the phenotypic consolidation coefficients in both ways) were the multiplicity rates of age uterus (48 months) for their insemination by age boars (48 months) in both summer and winter periods.