<div style="text-align: justify;">Asthenozoospermia puzzled poultry industry and little known about its characteristics. To explore the histological etiology of asthenozoospermia, we measured the sperm quality index (SQI) and Piwil1 expression in the testes of three types of asthenozoospermia roosters: field, artificial and normal. The SQI of field and artificial roosters was inferior to normal roosters. Further, busulfan could reduce sperm quality. Histological examination showed that the spermatids and spermatocyte of the seminiferous tubule was stripped layer-by-layer in field and artificial roosters. The absolute expression of Piwi11 in the normal group was significantly higher than that in the other two groups, and decreased with time. Piwi11 transcript expression rapidly decreased after 7 days post-injection (dpi); the lowest level was 13 dpi and did not change thereafter. Overall, our results indicate that busulfan causes structural damage to the seminiferous tubules, which can lead to asthenozoospermia, and that Piwil1 gene is a marker gene of asthenozoospermia.</div>

Histological verification of seminiferous tubule structure injury a cause of asthenozoospermia in chicken