Maturation competence and chromatin behaviour in growing and fully grown cattle oocytes.
Chromatin configurations of cattle oocytes from different follicle sizes were classified in three chromatin categories. Early diplotenes, dictyate-like structures, more progressed diplotenes and early diakinesis and metaphases were found. In follicle group A (0.4-0.9 mm) immature diplotenes predominated (82.3%), and a rather low maturation competence was observed (12.1%). With increasing follicle size the maturation competence was improved to 47.8% metaphases II in follicle group C (3-8 mm). Impressive CMA3 positive blocks were visualized especially in early diplotenes. Heterochromatic CMA3 positive clusters surrounded the nucleolus.
Führer
F
F
Mayr
B
B
Schellander
K
K
Kalat
M
M
Schleger
W
W
D000818:Animals; D002417:Cattle / Q000502:physiology*; D002843:Chromatin / Q000502:physiology*; D005260:Female; D009865:Oocytes / Q000254:growth & development* / Q000648:ultrastructure
D002843:Chromatin