biostudies-literatureUnknown12Van den Branden E<h4>Introduction</h4>The use of transvaginal ultrasound-guided follicle aspiration (TVA) for oocyte collection has become a widely used procedure in horses for <i>in vitro</i> embryo production (IVEP). The TVA procedure is characterized by various manipulations, which are physical restraint, perineal preparation, transrectal palpation, insertion of an intravaginal device, and needle punctures. These repeated transvaginal and transovarian punctures have raised concerns about their potential effects on mare welfare. Our study aimed to investigate the effects of TVA manipulations, and especially puncturing, on pain and stress in mares in a commercial set-up.<h4>Methods</h4>Therefore, eight mares were subjected to three TVA procedures: two with puncturing (P⁺) and one without (P<supFrontiers in veterinary science1574351https://www.ebi.ac.uk/biostudies/studies/S-EPMC12014748biostudies-literaturePhysiological and behavioral parameters of pain and stress in mares during and after transvaginal ultrasound-guided follicular aspiration.PMC12014748Salamone MPeere SPolfliet EBroothaers Kvan Loon GGovaere JVan Steenkiste GSmits KVan den Branden EDewulf MfalsePhysiological and behavioral parameters of pain and stress in mares during and after transvaginal ultrasound-guided follicular aspiration.<h4>Introduction</h4>The use of transvaginal ultrasound-guided follicle aspiration (TVA) for oocyte collection has become a widely used procedure in horses for <i>in vitro</i> embryo production (IVEP). The TVA procedure is characterized by various manipulations, which are physical restraint, perineal preparation, transrectal palpation, insertion of an intravaginal device, and needle punctures. These repeated transvaginal and transovarian punctures have raised concerns about their potential effects on mare welfare. Our study aimed to investigate the effects of TVA manipulations, and especially puncturing, on pain and stress in mares in a commercial set-up.<h4>Methods</h4>Therefore, eight mares were subjected to three TVA procedures: two with puncturing (P⁺) and one without (P<sup2025-01-01T00:00:00Z20252025-07-03T03:04:21.458Z2025-07-03T03:04:21.458ZS-EPMC120147484027148410.3389/fvets.2025.1574351