There are about 11 breeds, used in Ukrainian pig farms. This allows getting different breed combinations. Improving of Ukrainian pig breeds is increasingly going on with the foreign pig genotypes use. Therefore, in recent years there is intensive flow of pigs from abroad. Pigs from abroad are used for pure breeding and crossbreeding, thus positively affecting productivity of Ukrainian pig breeds.

The results of influence of Danish origin boars genotype and age (Landrace, Large white, Duroc), the Ukrainian origin boars (Yorkshire, Peitrain) and hybrid boars (Landrace × Large white, Peitrain × Duroc) on reproductive parameters of sows in herd of the JSC “Podilia” in Vinnytsia region are presented in the article.

It was established that multi-fertility of sows, which were inseminated by Danish boars, was on the level of 10,5−11,0 heads. Multi-fertility of sows, which were inseminated by Ukrainian boars, was at 9,5−10,0 heads. Multi-fertility of sows, which were inseminated by hybrid boars Peitrain × Duroc, was 11,8 heads. It was higher than multi-fertility of hybrid boars Landrace × Large white on 1,0 head. On average significantly higher parameters of multi-fertility characterizes sows, which were inseminated by crosses boars compared with sows, inseminated by Danish boars – 11,1 heads (p<0,001), it’s on 0,6 heards higher than multi-fertility of sows, which were inseminated by Danish boars, and on 1,6 heads – with Ukrainian boars.

Descendants of Large white breed are characterized by the highest level of piglets survival (96,5 %), the lowest − Yorkshire breed of Ukrainian origin (76,8 %). The best among hybrids are descendants with fathers genotype Peitrain × Duroc: the level of piglets survival is 91,2% (p<0,001). On average the best level of piglets survival have pigs of Danish origin – 93,5%, which is significantly proved (p<0,01); they have the advantage towards descendants of Ukrainian boars by 9,2 % and descendants of hybrid boars by 5,0 %.

On average mass of piglet of sows, which were inseminated by Danish boars, was 1,25 kg, by Ukrainian boars – 1,09 kg, by hybrid boars – 1,43 kg. Namely, the best parameters of piglet mass characterizes the cross, they have the advantage towards Danish origin group − by 0,18 kg and Ukrainian origin group − by 0,34 kg.

Therefore, better parameters of mass of piglet among purebred boars has Large white breed piglets of Danish origin (1,36 kg), the worse – Yorkshire breed piglets of Ukrainian origin (1,0 kg). The best parameters of mass of piglet has descendants of hybryd Peitrain × Duroc – that is 1,5 kg (p<0,05).

The influence of boars age on reproductive ability of sows was found. The general trend is slightly higher reproductive ability of sows which were inseminated by younger boars (aged 12−18 months). The percentage of farrowed sows are 83,1 % for boars of Ukrainian origin and 85,6 % − for cross boars, those are by 12,4 % and 13,4 % respectively higher, than for sows inseminated by boars older than 18 months. In group of Ukrainian boars higher level of multi-fertility characterizes sows, inseminated by boars in age 12−18 months – 11,3 heads (p<0,001), that on 1,4 heads prevail sows, which were inseminated by older boars. The highest parameters of multi-fertility among hybrids has sows, which were inseminated by boars 12−18 months (12,6 heads, p<0,001), which on 4,2 heads prevail sows inseminated by boars older than 18 months.

 The highest level of piglets survival have both Ukrainian and hybrid boars, which were mated at age 12−18 months  – 84,7 % and 92,3 %, respectively.  It is on 18,2−21,0 % more than piglets survival of older boars (aged 18 months and older). The best among hybryds in piglets survival are descendants of young boars – 92,3% (p<0,001). Therefore, more effective is the use of boars aged 12−18 months, as they characterizes by a high percentage of farrowed sows, which were inseminated by them, and have better parameters of multi-fertility and piglets survival to weaning, these parameters are significantly higher (p<0,001).

Key words: pigs, genotype, age, multi-fertility of sows, mass of piglet, piglets’ survival.