Ovary maturation stages histology and follicles diameter of Melanotaenia boesemani rainbowfish ovary from district of North Ayamaru, Maybrat Regency, West Papua

Introduction: This research aim is to described ovary maturation stages histologically related with oocytes development in ovary of boesemani rainbowfish M. boesemani from North Ayamaru district, Maybrat Regency, West Papua. Materials and Methods: A histologycal analysis of ovari maturation stage (OMS) of the Boesemani rainbowfish Melanotaenia boesemani performed on 93 ovaries. Fresh ovaries were fixed in 10% Neutral Buffered Formalin (NBF) and embedded in paraffin. Section of about 5-6 μm thickness were cut and stained with Hematoxylin eosin (HE). Results: Histologycal analysis of rainbowfish M. boesemani ovaries based on oocyte development consist of 8 oocyte types not included atresia follicle i.e oogonia, early perinuclear oocyte, late perinuclear oocyte, cortical alveoli oocyte, early vitelogenic oocyte, mid-vitelogenic oocyte, late vitelogenic oocyte, and mature oocyte. The chorion and follicle layers begins to form at OMS II, keeps growing at OMS III, and was apparent at OMS IV. The chorion and follicle layers at OMS V ovaries were disintegrated. Conclusion: Based on ovary histology, oocyte proportion, and follicles diameter distribution can be concluded that the rainbowfish M. boesemani classified as multiple spawner.