Age dynamics of reproductive qualities of sows depending on the duration of the suckling period

The article studied the influence of sows' age on their reproductive qualities at the traditional - 28 days and shortened - 21 days duration of the suckling period. It was found that the total number of piglets born increased from the second reproductive cycle to the sixth inclusive. With the traditional duration of the suckling period, the most significant growth was observed during the third, fourth and fifth farrowing (8.0-8.6%), while with a reduced duration of the suckling period, it was significantly lower (3.8-4.9%). and lasted from the third to the fifth reproductive cycle. As sows' reproductive age increased, their fertility increased. Its highest growth in both terms of weaning of piglets was on the third farrowing and then gradually decreased. Sows with a reduced suckling period had a lower increase in fertility throughout reproductive life. The nest weight of piglets at birth increased until the third farrowing and then gradually decreased. With the traditional duration of the suckling period, the intensity of the increase in the nest weight of piglets born at the age of sows is higher compared to analogues in which the lactation period was reduced. Preservation of piglets in sows' nests deteriorated with increasing reproductive age. It worsened less intensely in sows with a reduced suckling period. The number of weaned piglets depended to a greater extent on the age of the sows and to a lesser extent on the length of the suckling period. From the third farrowing, it constantly decreases with increasing age of the sow, regardless of the length of the suckling period. The average weight of one piglet increases with the age of sows from the third farrowing, and its growth is more intense with a reduced duration of lactation. The increase in the weight of the nest of piglets at weaning is most significant for 3-5 farrowings, after which there was a decrease in this indicator for both periods of weaning piglets. A comprehensive assessment of the reproductive quality of sows using indices confirms the increase in sow productivity during the second - fourth reproductive cycle with a gradual decrease during the fifth to sixth farrowing, both in the traditional and reduced duration of the suckling period. It is proved that the sow age factor determines the probable influence on the number of piglets at weaning (9.43 %), their safety (5.56 %), the weight of the nest of piglets at weaning (1.87 %) and fertility (1.65 % ). While the suckling period factor affected the nest weight of piglets at weaning with a force of 28.49 %, the number of piglets at weaning with a force of 0.62 %, the safety of piglets before weaning at 0.19 % and did not affect the fertility of sows