Abstract. The objective of this article was the evaluation of selected properties of meat quality including the
characteristics of longissimus lumborum (LL) muscle microstructure of Pulawska breed pigs and fatteners of the
DanBred and Naima hybrids which are used in national meat production. Three genetic groups of fatteners were
studied in the experiment: group I – DanBred hybrid; group II – Naima hybrid; and group III – the Pulawska
breed. Pig fattening took place under the same environmental conditions from the starting weight of 30 kg ± 2 kg
to 103–105 kg. For the analysis of muscle fibre characteristics and meat quality from each group, 30 animals were
selected ( 1 : 1 ). Physico-chemical properties and ultrastructure were evaluated in samples collected from the
LL muscle. A statistically significant impact (P