175 FOLLICULAR DIAMETER AND OVULATION RATE IN NELLORE COWS TREATED WITH LH
Notice bibliographique
Résumé
The aim of the present experiment was to verify the correlation between follicular diameter and ovulation rate in Nellore cows submitted to LH treatment to add information to the limited literature about this subject. A preliminary test (experiment 1) was performed to determine the lowest dose of LH necessary to induce ovulation in follicles with diameter =10 mm. At a random stage of the estrous cycle (D0), Nellore cows (n = 20) received a progesterone intravaginal device (1.0 g, Primer®, Tecnopec, Sao Paulo, Brazil) and 2.5 mg of estradiol benzoate (EB, i.m., Estrogin®; Farmavet, Sao Paulo, Brazil). Eight days later (D8) PGF2a was administered (150 µg of D-cloprostenol, i.m., Prolise® ARSA S.R.L., Buenos Aires, Argentina) and the device was removed. Twenty-four hours after device removal, cows were treated with EB (1.0 mg, i.m.) and 48 h afterward; ovulation was determined by ultrasonography (US, Aloka 900, Tokyo, Japan). Three days after ovulation, the follicular growth was daily observed by US, and when the follicles reached =10 mm diameter, the cows were randomly allocated in 4 groups and treated with different doses of LH (i.m., Lutropin-V®, Bioniche, Ontario, Canada): Groups 1.56; 3.12; 6.25, and 12.5 mg. The data were analyzed by Fisher’s Exact Test (PROC FREQ, SAS). The ovulation rates were 0% (0/5), 80% (4/5), 80% (4/5), and 80% (4/5) respectively, and it was lower in group 1.56 when compared with the others (P < 0.02). Taking in account the results above, the dose of 6.25 mg to induce ovulation in Nellore cows (n = 58, experiment 2) submitted to the same protocol used in experiment 1 and randomly allocated in 5 groups according to follicular diameter at the time of LH administration: G1 (7.0–7.5 mm), G2 (7.6–8.0 mm), G3 (8.1–8.5 mm), G4 (8.6–9.0 mm), and G5 (9.1–10.0 mm). The results were analyzed by Logistic Regression (PROC GENMOD, SAS). The ovulation rates were 0% (0/11), 20% (2/10), 36% (4/11), 36% (4/11), and 90% (9/10), respectively, for G1, G2, G3, G4, and G5. When the data from 2 groups (except G5) were combined, G1 + G2 (7.0–8.0 mm), G3 + G4 (8.1–9.0 mm), and G5 (9.1–10.0) ovulation rates were, respectively, 9% (2/21), 36% (8/22), and 90% (9/10). There were significant differences when comparing G1 + G2 v. G5 (P < 0.01), G3 + G4 v. G5 (P < 0.02) and G1 + G2 v. G3 + G4 (P < 0.03). After LH application, the smallest follicle that ovulated had a diameter of 7.65 mm. In summary, although LH administration induced ovulation in one follicle of 7.65 mm, high ovulation rates were observed only when the follicles reached <9.0 mm. These data will be used to study the correlation between ovulation rate and expression of isoforms of LH mRNA receptors in theca and granulosa cells. Fellowship from *FAPESP (Sao Paulo, Brazil) and **CAPES (Brasilia, Brazil).
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 | 0,000 | 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 ».