{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,26]],"date-time":"2026-10-26T19:23:49Z","timestamp":1793042629704,"version":"4.5.0"},"reference-count":39,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T00:00:00Z","timestamp":1768435200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100012905","name":"Department of Science & Technology of Shandong Province","doi-asserted-by":"crossref","award":["2025TSGCCZZB0330"],"award-info":[{"award-number":["2025TSGCCZZB0330"]}],"id":[{"id":"10.13039\/100012905","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Accurate and quantitative detection of boar sperm heads is essential for breeding selection and reproductive management. Manual microscopic counting is time-consuming, labor-intensive, and prone to subjective bias, while existing computer-based algorithms often struggle to recognize sperm cells accurately when they overlap or move rapidly in high-magnification microscopic images. This study proposes a lightweight boar sperm detection model, YOLO11_SRP, designed to improve small-object recognition in complex microscopic scenarios. The model integrates a lightweight StarNet backbone, a rectangular self-calibration module for enhanced spatial feature modeling, and an additional low-level detection layer optimized for tiny targets. We evaluated the model on a boar sperm microscopic image dataset and compared it with the standard YOLO11s framework. The results show that YOLO11_SRP achieves an mAP@0.5 of 91.9%, representing a 13.9% improvement over YOLO11s, while simultaneously reducing parameters by 39% and computational cost by 14.1%. These findings demonstrate that YOLO11_SRP provides efficient and accurate sperm detection, supporting the development of efficient and reliable automated sperm analysis pipelines, in which sperm head detection serves as a fundamental preprocessing step.<\/jats:p>","DOI":"10.3390\/ani16020258","type":"journal-article","created":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T11:13:21Z","timestamp":1768475601000},"page":"258","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["A Novel Lightweight Deep Learning Model for Boar Sperm Head Detection in Microscopic Images: YOLO11_SRP"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-2520-7140","authenticated-orcid":false,"given":"Mingchao","family":"Pan","sequence":"first","affiliation":[{"name":"College of Automation and Electronic Engineering, Qingdao University of Science and Technology, Qingdao 266061, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-4513-1446","authenticated-orcid":false,"given":"Lin","family":"Gao","sequence":"additional","affiliation":[{"name":"College of Automation and Electronic Engineering, Qingdao University of Science and Technology, Qingdao 266061, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhendong","family":"Zhu","sequence":"additional","affiliation":[{"name":"College of Animal Science and Technology, Qingdao Agricultural University, Qingdao 266109, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yingqi","family":"Li","sequence":"additional","affiliation":[{"name":"College of Automation and Electronic Engineering, Qingdao University of Science and Technology, Qingdao 266061, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mingkang","family":"Gao","sequence":"additional","affiliation":[{"name":"College of Automation and Electronic Engineering, Qingdao University of Science and Technology, Qingdao 266061, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1016\/j.theriogenology.2015.07.009","article-title":"Artificial insemination in pigs today","volume":"85","author":"Knox","year":"2016","journal-title":"Theriogenology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"312","DOI":"10.1002\/j.1939-4640.1997.tb01925.x","article-title":"Objectively measured boar sperm motility parameters correlate with the outcomes of on-farm inseminations: Results of two fertility trials","volume":"18","author":"Holt","year":"1997","journal-title":"J. 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