The aim of the study: To evaluate size peculiarities of testes and accessory sexual glands, peculiarities of their morphological variables and their correlation with sperm qualitative and quantitative indices of breeding boars kept in Lithuania. The purpose of the study: 1. To analyze the causes for boar culling. 2. To investigate pathological morphological variables and their influence on ejaculate volume in culled boars at various periods of age. 3. To analyze quantitative parameters of testes collagen network considering the age of boars and pathological parameters. 4. To determine the size and weight impact of testes and accessory sexual glands on sperm quantity and quality. 5. To evaluate the impact of pathological variables in testes and accessory sexual glands on sperm quantity and quality. Conclusions: 1. In breeding enterprises from the year 2007 to 2011, a lot of breeding boars (46.5%) were culled. The most frequent causes were: poor sperm quality (43.4%), reduced libido (26.4%), for the reasons of selection (11.3%) and causes not related to reproduction (19%). 2. Having performed morphological examination in the testes of breeding boars, mixed pathologies were determined. Prevailing pathologies were: degeneration (60.86%), fibrosis (26.08%), inflammation (13.04%). The variables in the left and right testes usually differed. 3. With the ageing of the boar, the development of pathologies in the testes made greater impact on healthiness and fertility of the animal, and degenerative and fibroid variables in testes were more frequent. The increased rate of incidence of acute inflammation was more frequently determined at the most productive age of boars (18–30 mo). With ageing the decrease of inflammations in testes was statistically significant (P0.05). 9. The degree of degeneration in testis influenced spermatozoa motility most significantly. In case of severe degeneration, the motility of spermatozoa was 45.00±17.32% lower in comparison to that in case of low degeneration (P≤0.05). 10. The pathology of spermatozoa tails was influenced mainly by the degree of degeneration in testes. Under severe pathology, the occurrence of coiled tails was 30.73±19.33% higher than in cases of low degeneration (P≤0.05). 11. The fibrosis determined in testes positively correlated with the motility of spermatozoa (r=0.429; P≤0.05) and concentration of spermatozoa (r=-0.427; P≤0.05), but negatively – with a total count of pathological spermatozoa in ejaculate (r=0.424; P≤0.05).