212 EFFECT OF CRYOPRESERVATION METHODS AND PRE-CRYOPRESERVATION STORAGE ON BOTTLENOSE DOLPHIN (TURSIOPS TRUNCATES) SPERMATOZOA
Notice bibliographique
Résumé
In conjunction with artificial insemination (AI) and sperm preservation, sperm sexing technology has great potential as a population management strategy for captive bottlenose dolphins. Successful AI using fresh spermatozoa (Robeck TR et al. 2001 CRC Marine Mammal Medicine 193–226) and flow cytometric analysis of bottlenose dolphin spermatozoa (Garner DL and Seidel GE Jr 2002 CSAS Symposium 2–13) support this approach. For sperm sexing, methods for short-term storage of semen in a liquid state are required to enable transport of spermatozoa to the sorting laboratory. In addition, cryopreservation techniques must be optimized for long-term storage of sexed spermatozoa. Our objectives were to assess: (i) 3 cryopreservation methods × 2 straw sizes × 3 thawing rates (Exp. 1) and (ii) effects of liquid storage for 24 h (pre-cryopreservation) and sperm concentration at freezing (Exp. 2) on post-thaw characteristics (PT) of bottlenose dolphin spermatozoa. For Exp. 1 and 2, 4 ejaculates (collected by manual stimulation) × 3 males (aged 14–34 yr) × 4 replicates were used. For Exp. 1, semen was frozen in 0.25-mL (SM) and 0.5-mL straws (LG) by 3 methods (Mt) (Mt1: lactose, egg yolk, -32°C min-1; Mt2: lactose, egg yolk, 1.5% Equex STM (Nova Chemical, Calgary, Canada), -19.7°C min-1; Mt3: Test yolk buffer (TYB), -116°C min-1). All Mt had 3% glycerol. Samples were thawed using a slow (S: 2.8°C s-1), medium (M: 8.8°C s-1) or fast (F: 21°C s-1) rate. In Exp. 2, ejaculates were divided into 4 aliquots for dilution (1:1) and stored at 4°C with EquiPro® (EP4°C, Minitube, Verona, WI, USA) and TYB (TYB4°C) or at 21°C with Androhep EnduraguardTM (AH21°C, Minitube) or no dilution (NEAT21°C). After 24 h, samples were frozen and thawed using Mt3 × SM × F at 10 × 106 sperm mL-1 (LOW) or 100 × 106 sperm mL-1 (STD). PT evaluations of motility (total motility [TM], % progressive motility [PPM], kinetic rating [KR, 0 to 5]) and acrosomal status (Spermac® , Minitube) were performed at 30 min and 6 h after dilution (1:1) with AH at 21°C. For statistical analysis (ANOVA), a sperm motility index (SMI = TM × PPM × KR) was calculated and expressed as % of initial SMI. For all ejaculates, initial TM and PPM were greater than 85% and KR was 5. In Exp. 1, at 6 h PT, %SMI was highest for Mt3 × LG × M (45.5 ± 8.7) and Mt3 × SM × F (44.8 ± 11.9). For Exp. 2, %SMI at 0 h PT was higher for samples stored at 4°C than at 21°C (TYB4°C 41.0 ± 8.4, EP4°C: 36.7 ± 7.7, NEAT21°C: 23.8 ± 8.6, AH21°C: 14.8 ± 8.6, P < 0.001) and, with the exception of AH21°C, was similar between the LOW and STD concentration. At 6 h PT, %SMI for all treatments was higher for STD than LOW concentration (P < 0.05). Acrosome integrity was similar across treatments. In summary, a semen cryopreservation protocol maintained high levels of the initial characteristics of ejaculated spermatozoa. Transport of semen for sex pre-selection and cryopreservation within 24 h may be feasible, but impact of storage time on functional capacity of dolphin spermatozoa is unknown.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,002 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».