Department of Histology and Embryology, Academy
of Medicine, 1Department of Anatomy and Physiology, Veterinary
Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania
Key words: pig, oocyte, morphometric analysis
Aim of this work was to investigate the
differences of morphometric parameters of 6-8 months old pigs’ oocytes which
were derived from preantral ovarian follicles.
Ovaries were taken from 3 pigs’ groups: group 1
(6 months old), group 2 (7 months old) and group 3 (8 months old).
Ovaries were obtained from a slaughterhouse and transported at 37°C in 0.9% NaCl. In the laboratory oocytes were aspirated from 3–6 mm diameter follicles with needle to a 10 ml syringe. Oocytes were washed in 0.9% NaCl saline. Only oocytes surrounded by ≥ 3 cumulus cell layers of unexpanded cumulus cells and an evenly granulated cytoplasm were selected under a stereomicroscope. Microphotographs of oocytes were made. Morphometric analyse of these oocytes was done using UTHSCSA Image Tool for Windows Version 1.27 program. The diameter and areas of oocytes, cytoplasm and nuclei and the thickness of zona pellucida and perivitelline space were analysed in 5 oocytes of each pig. Results were analysed using the ANOVA program (Statistica Version 5, StatSoft inc.).
The diameter of the primary oocytes, which were
in antral ovarian follicles of investigated pigs’ group 1 (115.45±2.62 µm), was
less than in group 2 (115.48±4.44 µm) and group 3 (115.5±3.54 µm), but these
results differed not significant (P≥0.05).
The area of oocytes of all 3 pigs’ groups was
similar. It was 10610.78±669.23 µm2 of size in the group 1,
10612.76±613.14 µm2 of size in the group 2 and 10658.78±295.06 µm2
in the group 3 (P≥0.05).
The zona
pelucida was 10.89±0.45 µm of thickness in the oocytes of pigs’ group 1,
10.86±0.34 µm of pigs’ group 2 and 10.88±0.18 µm of the group 3 (P≥0.05).
The perivitelline space was 3.64±0.18 µm of
thickness in the oocytes of pigs’ group 1, 3.62±0.65 µm of group 2 and 3.61±0.52 µm of the group 3 (P≥0.05).
The diameter of cytoplasm was 82.67±3.26 µm of
size in the group 1, 82.87±3.74 µm2 of size in the group 2, and
82.88±1.99 µm2 in the group 3 (P≥0.05).
The area of the cytoplasm, which was in oocytes of investigated 6-8 months old pigs, differed not significant (from 5439.19±177.83 µm2 to 5445.1±185.05 µm2, P≥0.05).
There were no differences in diameter and area
of oocytes and their cytoplasm and the thickness of zona pellucida and perivitelline space in the oocytes of 6-8 months
old pigs’ oocytes which were derived from preantral ovarian follicles
(P≥0.05).
Aleksandras.Vitkus@lsmuni.lt