In the present study the effect of boar age and seasonal changes on oxygen uptake (ZO₂) and ATP content in spermatozoa during storage at 5° and 16°C were analysed. Semen was collected from 3 Polish Landrace boars for a 3-year period. The semen was extended in a standard semen extender, Kortowo 3 (K3), which was supplemented with lipoprotein fractions extracted from hen (K3-LPFh) or ostrich egg yolk (K3-LPFo). Irrespective of the storage temperatures, lower metabolic activity was manifested in reduced ZO₂ values and ATP content in spermatozoa stored in K3 extender. The metabolic performance of spermatozoa from boars aged 25-36 months was higher, particularly during the autumn-winter period. The addition of lipoprotein fractions to the semen extender had a beneficial effect on the analysed biochemical parameters of the metabolic activity of spermatozoa preserved at 5°C. This seems to indicate that boar age and the season may be important factors that can influence the use of semen for liquid preservation.