Neonatal and Juvenile Ocular Development in Sprague‐Dawley Rats: a Histomorphological Study
Bibliographic record
Abstract
This study aimed at evaluating the histomorphological developmental features of the eye in Sprague‐Dawley rats, with focus on the postnatal and juvenile periods. Tissues were collected from 51 rats, from both sexes, aged 1 to 30 days old. As in other altricial species, the eyes of newborn rats are underdeveloped and the eyelids remain closed for approximately two weeks after birth. During the postnatal development, dramatic changes occurred within the retina, when programmed cell death and cell differentiation coexisted. A complete separation of the inner nuclear layer from outer nuclear layer was first observed close to the end of the first week of life, while the nerve fiber, ganglion cell and inner plexiform layers almost reached maturity concurrently with the opening of the eyes, around the end of the second week. At birth, apoptotic bodies were frequently seen within the undifferentiated nuclear layer and peaked at post‐natal day (PND) 8 within the inner nuclear layer. In newborn animals, mitoses formed a contiguous band of proliferating cells within the undifferentiated nuclear layer, adjacent to the photoreceptors layer. Perinatally, the corneal stroma and sclera exhibited high cellularity and became thinner and less cellular with maturity. The corneal epithelium consisted of a single layer of non‐stratified columnar cells during the first ten PNDs, and transformed into 4 to 5 cell layers of stratified squamous epithelium at about PND 14. The lens continuously developed by addition of new lens fibers from the lens epithelium. Between PND8 and PND17, a band‐like region of apoptotic bodies was seen centrally within the zone of nucleated lens fibers. We conclude that, during the first month of life, the rat's eyes undergo a rapid phase of growth and almost reach adult maturity at PND30. These observations will serve as an historical database, useful in pediatric ocular drug development. Support or Funding Information Mitacs
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.001 | 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 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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".