Hormonal stimulation in Nelore calves for in vitro embryo production
Bibliographic record
Abstract
The study of reproductive management on prepubertal bovine females for including these animals in the IVF could be an alternative for accelerating genetic gain by reducing the generation interval. This work aimed to evaluate a hormonal treatment response on the ovarian characteristics and on the OPU (Laparoscope Storz Xenon300W. Tuttlingen, Germany)/IVF in 9 Nelore calves (cross-over design) 4-7 months old. In the control group (CG, n=9) transrectal ultrasonography (US) was performed daily (MyLab 30VetGold,Esaote, 5-7,5MHz transducer. Genova, Italy) during 8 days (D0 to OPU) and ablation of larger follicles was performed on D2 (5 days before OPU). In the treated group (TG, n=9) US was also performed during 8 days, which D0 represented the start of treatment (Intravaginal device. Progesterone-P4 0.33g. Eazi-Breed-CIDR, Pfizer Animal Health, Brazil) including an injection of estradiol benzoate (im. 2mg. Ric-BE, Tecnopec-Brazil). From the D4 on, 6 FSH injections were administered, during 3 days (im. 12/12h: 40mg+5 20mg doses. Total:140mg; Folltropin, Bioniche Animal Health, BellevilleOntario, Canada). On the last FSH dose, it was administered 2.5mg of LH (im. Lutropin, Bioniche Animal Health, Belleville-Ontario, Canada). The OPU was performed 20-24h after the last FSH injection (D7). The P4 devices were removed right after the OPU. Aspirated COCs were selected, matured, fertilized and cultured in vitro until D7. As IVF control, COCs obtained from slaughterhouse ovaries were used (Slaughterhouse Group-SG). The US or OPU grouped data were simultaneously compared between CG vs TG on D0 and D7 and analyzed according to their distribution, by t and Man-Whitney tests. The IVF results were compared among CG, TG and SG by Chi-square test and Kruskal Wallis (PROPHET 5.0, BBN-Systems&Technologies, Cambridge-Massachusetts, USA). The TG had increased (p 0.05) the cleavage rate (49.33% vs 51.42%, respectively CG vs TG), the rate and the number of blastocysts in D7 (1.33% vs 8.57% or 3 vs 9, respectively for rate or number in CG vs TG. SG blastocysts rate: 24.41%) nor the number of embryos/female donor (0.33 vs 1.0, respectively CG vs TG). It was concluded that this hormonal treatment increased the number of observed and aspirated follicles, grade I and II oocytes, but it did not increase embryo production on these animals.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".