TY - JOUR

T1 - Description of the Seminiferous Epithelium Cycle Stages in the Zebra Finch Taeniopygia guttata

AU - Bikchurina, Tatiana

AU - Rubtsova, Daria

AU - Odnoprienko, Daria

AU - Borodin, Pavel

AU - Torgasheva, Anna

AU - Malinovskaya, Lyubov

N1 - This research was funded by the Russian Science Foundation, grant number 23-14-00182.

PY - 2025/11/27

Y1 - 2025/11/27

N2 - Spermatogenesis in passerine birds remains poorly characterized. Previous studies focused on the steps of spermiogenesis, while a detailed staging of the seminiferous epithelium cycle is still lacking for this order. In this study, we provide the first comprehensive histological characterization of spermatogenesis in a model passerine species, the zebra finch. We defined ten distinct steps of spermiogenesis based on acrosomal and nuclear morphology of spermatids in Periodic acid–Schiff-stained histological sections. Using this classification, we further defined seven stages of the seminiferous epithelium, encompassing cytological features associated with the programmed DNA elimination, which is unique to passerines. Our analysis revealed that seminiferous tubules of the zebra finch exhibit a mosaic organization typical of all birds examined so far. However, in this species, most stages were characterized by the presence of spermatids at three developmental steps, in contrast to the one to two steps typical of non-passerine birds. To facilitate future comparative studies, we developed a flowchart for determining the stages of the seminiferous epithelium cycle. This work establishes an essential histological framework for future research in reproductive biology of the zebra finch and other passerine species.

AB - Spermatogenesis in passerine birds remains poorly characterized. Previous studies focused on the steps of spermiogenesis, while a detailed staging of the seminiferous epithelium cycle is still lacking for this order. In this study, we provide the first comprehensive histological characterization of spermatogenesis in a model passerine species, the zebra finch. We defined ten distinct steps of spermiogenesis based on acrosomal and nuclear morphology of spermatids in Periodic acid–Schiff-stained histological sections. Using this classification, we further defined seven stages of the seminiferous epithelium, encompassing cytological features associated with the programmed DNA elimination, which is unique to passerines. Our analysis revealed that seminiferous tubules of the zebra finch exhibit a mosaic organization typical of all birds examined so far. However, in this species, most stages were characterized by the presence of spermatids at three developmental steps, in contrast to the one to two steps typical of non-passerine birds. To facilitate future comparative studies, we developed a flowchart for determining the stages of the seminiferous epithelium cycle. This work establishes an essential histological framework for future research in reproductive biology of the zebra finch and other passerine species.

KW - germline-restricted chromosome (GRC)

KW - seminiferous epithelium cycle

KW - spermatogenesis

KW - spermiogenesis

KW - zebra finch

UR - https://www.scopus.com/pages/publications/105024607581

UR - https://www.mendeley.com/catalogue/b204bcbd-9a23-3f57-b23c-c2c095698138/

U2 - 10.3390/ani15233427

DO - 10.3390/ani15233427

M3 - Article

C2 - 41375485

VL - 15

JO - Animals

JF - Animals

SN - 2076-2615

IS - 23

M1 - 3427

ER -