Essentials of Veterinary Ophthalmology. Kirk N. Gelatt

— Branches of the central retinal artery form 4 51 Pupillary sphincter differentiates Retinal vessels present — 56 Ciliary muscle appears — Tapetum present (dog) 5 40 Layers of the choroid are complete with pigmentation 6 — Eyelids begin to open, light perception 1P Pupillary dilator muscle present 7 1–14P Pupillary membrane atrophies 1–16P Rod and cone inner and outer segments present in posterior retina 10–13P Pars plana distinct 9 16–40P Retinal layers developed 14P Regression of pupillary membrane, TVL, and hyaloid artery nearly complete Lacrimal duct canalized

Table 1.2 Sequence of ocular development in the cow.

Ocular part or event	Gestational size (mm)
Lens
Optic vesicle	6
Lens placode	6
Optic cup and lens placode	10
Separation of lens vesicle from surface ectoderm	10
Primary lens fibers	15
Lens vesicle cavity disappears	24
Completion of lens capsule	50
Secondary lens fibers	58
Perilenticular vascular mesoderm
Extension of primary vitreous (hyaloid artery) to lens	15
TVL	33
Disappearance of posterior lenticular vascular network	410
Disappearance of TVL	410
Iris
Major arterial circle of iris	90
Iris reaches front of lens	200
Pigment in stroma	200
Sphincter muscle	410
Dilator muscle	410
Ciliary body
Ciliary processes	125
Ciliary processes touch lens equator	230
Pars plana (distinct)	200
Pars plana fully developed	410
Choroid
Choroidal net in posterior pole	33
Choroidal net throughout	50
Outermost large choroidal vessels	40
Choriocapillaris	90
Pigmentation of choroid	90
Retina – posterior third
Inner and outer nucleated zones	10
Multilayer outer cup of optic vesicle forms single cells	20
Nerve fiber layer	20
Optic nerve well formed	24
Inner/outer neuroblastic layers	14
Transient layer of Chievitz	14
Inner plexiform layer	180 Скачать книгу В начало < 18 19 20 21 22 23 24 25 26 27 > В конец