The objective of the experiment was to determine the effect of pre-slaughter weight growth from 100 to 120 kg on the change of slaughter indicators in Landrace pigs of Irish origin. Two groups with equal numbers of gilts and barrows were fattened in identical piggeries. Two groups with equal numbers of gilts and barrows were fattened in identical piggeries and then they were divided into two groups by weighing. First group included 30 pigs weighing 100 kg, second group included 30 pigs weighing 120 kg. Pigs were slaughtered, their carcasses were deboned and carcass parameters were measured. A significant correlation was found between pre-slaughter weight and weight of chilled carcass r = 0.95, carcass length r = 0.76, bacon half length r = 0.74, fat thickness over 6-7 thoracic vertebrae r = 0.49, fat thickness in the withers r = 0.49, area of the longest back muscle r = 0.47, carcass weight loss after cooling r = 0.37, fat thickness in the buttocks r = 0.23, slaughter yield r = -0.16 and meat content in the carcass r = -0.08. The increase in pre-slaughter weight by 1 kg after reaching 100 kg, led to an increase in slaughter weight by 0.73 kg of chilled carcass weight by 0.70, fat thickness over 6-7 thoracic vertebrae by 0.25 mm, fat thickness at withers by 0, 28 mm, carcass length by 0.27 cm, bacon half length by 0.24 cm and longest back muscle area 0.22 cm².

The pigs were transported to the slaughterhouse of Globinsky Meat Factory LLC, Poltava region, Ukraine under the same conditions of transportation. Upon arrival, the pigs were left without food for 24 hours with access to water. At the end of the fasting period, experimental pigs were slaughtered due to stunning in the gas chamber Schaller Butina DK 4300 (Butina ApS, Denmark). The slaughter was performed in accordance with (ISO 23781: 2021). Before cooling in carcasses with the help of a ruler were measured: the fat thickness in the withers, the fat thickness over 6-7 thoracic vertebrae, the fat thickness in the buttocks, the carcass length, the bacon halves length. Slaughter weight of carcasses before cooling was measured using torsion scales mounted on a suspended conveyor.

Cooling of the carcass after slaughter was conducted in two periods. The first period of cooling the carcass was to a temperature of 14 ^oC for 105 min, the second period was to a temperature of 4 ^oC for 24 hours.

After 24 hours cooling, the carcasses were rolled in accordance with (ISO 3100-1) in a slaughterhouse and measured by ultrasonic Fat-o-Meat’er II (Frontmatec, Denmark) to determine the area of the longest back muscle. Indicators were also determined: weight of chilled carcass, losses after cooling 24 h, slaughter yield, meat content.