{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T12:34:28Z","timestamp":1792154068758,"version":"4.4.0"},"reference-count":41,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T00:00:00Z","timestamp":1786406400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Semen cryopreservation is widely used in canine breeding, but individual variation in post-thaw semen quality limits its efficiency. This study investigated whether testicular artery Doppler-derived blood-flow parameters and circulating vascular endothelial growth factor (VEGF) concentrations are associated with semen quality and sperm freezability in clinically healthy dogs. Sixty-four privately owned male dogs underwent reproductive screening, semen collection, testicular Doppler ultrasonography, blood sampling, fresh and post-thaw semen analysis, and plasma VEGF quantification. Testicular artery Doppler parameters were not significantly associated with fresh or post-thaw semen quality or with most freezability outcomes. Plasma VEGF concentration was positively correlated with fresh linearity (LIN) (p = 0.034), straightness (STR) (p = 0.031), and beat-cross frequency (BCF) (p = 0.043). Higher VEGF concentrations were associated with greater post-thaw declines in progressive motility (PM) (p = 0.036), straight-line velocity (VSL) (p = 0.032), LIN (p = 0.001), STR (p = 0.005), and wobble (WOB) (p = 0.010). In multivariable analysis, VEGF was associated with linearity decline (B = 0.595, 95% CI: 0.254\u20130.937; p = 0.001). Circulating VEGF may therefore be associated with individual variation in canine sperm cryotolerance, whereas testicular artery Doppler assessment showed limited value.<\/jats:p>","DOI":"10.3390\/ani16162500","type":"journal-article","created":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T10:32:16Z","timestamp":1786444336000},"page":"2500","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Association of Blood Plasma Vascular Endothelial Growth Factor and Testicular Artery Doppler Parameters with Canine Sperm Freezability"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2082-4539","authenticated-orcid":false,"given":"Florin Petri\u0219or","family":"Posastiuc","sequence":"first","affiliation":[{"name":"Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium"},{"name":"Department of Clinical Sciences II, Faculty of Veterinary Medicine, University of Agronomic Sciences and Veterinary Medicine of Bucharest, 105 Blvd. Splaiul Independentei, 050097 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6017-9263","authenticated-orcid":false,"given":"Guillaume","family":"Domain","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7604-6783","authenticated-orcid":false,"given":"Lotte","family":"Spanoghe","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joke","family":"Lannoo","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Penelope","family":"Banchi","sequence":"additional","affiliation":[{"name":"Department of Animal Breeding & Genomics, Wageningen University & Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mircea","family":"Petcu","sequence":"additional","affiliation":[{"name":"Department of Paraclinical Sciences, Faculty of Veterinary Medicine, University of Agronomic Sciences and Veterinary Medicine of Bucharest, 105 Blvd. Splaiul Independentei, 050097 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5010-6311","authenticated-orcid":false,"given":"Ann","family":"Van Soom","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Reproduction and Population Medicine, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1186\/s13028-025-00845-2","article-title":"A Review of Sperm Cryopreservation in the Domestic Dog and Cat: Part I, from Science to Clinic","volume":"68","year":"2025","journal-title":"Acta Vet. 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