What is the Granula Iridica?
What is the Granula Iridica?
The corpora nigra, also known as granula iridica, are the pigmented roughened prominences along the pupillary margin of ungulates. They are an extension of the posterior iris epithelium and consist of 2 layers of pigmented epithelium (1).
What are the components of the uvea?
It has three parts: (1) the iris, which is the colored part of the eye;(2) the ciliary body, which is the structure in the eye that secretes the transparent liquid within the eye; and (3) the choroid, which is the layer of blood vessels and connective tissue between the sclera and the retina.
What is the uvea?
The uvea is the middle layer of the eye. It lies beneath the white part of the eye (the sclera). It is made of the iris, ciliary body, and choroid.
What is Coloboma of iris?
Coloboma of the iris is a hole or defect of the iris of the eye. Most colobomas are present since birth (congenital). A cat eye is a type of coloboma. Any defect in the iris that allows light to enter the eye, other than through the pupil, is called a coloboma.
What is aqueous flare?
An aqueous flare is an optical phenomenon based on light scattering within the anterior chamber of the eye. This phenomenon occurs when an inflamed eye is viewed at right angles to a beam of light shined obliquely into the anterior chamber.
How do llama eyes work?
Llamas have iridic granules on the top and bottom of the pupil as well, however, they are more elongated than rounded. In bright sunlight these iridic granules can actually interdigitate to completely cover the centre of the pupil. This leaves just two holes open on either end of the pupil.
What is difference between choroid and uvea?
The uvea or vascular tunic of the eye consists of the choroid, ciliary body, and iris. The choroid lies between the sclera and RPE, and contains connective tissue, capillaries, and melanocytes. The choroid terminates anteriorly as the ciliary body.
What is retina and uvea?
The uvea is the middle layer of the eye between the sclera (white part of the eye) and the retina (light-sensitive layer at the back of the eye). It has 3 parts: Iris (the colored part of the eye) Ciliary body (the part of the eye that helps the lens focus)
How is coloboma caused?
What causes coloboma? Coloboma happens when a baby’s eye doesn’t develop normally during pregnancy because of abnormal or changed genes that affect eye development. Coloboma sometimes runs in families. Environmental factors, such as drinking alcohol during pregnancy, may also increase a baby’s risk for coloboma.
How does coloboma affect the eye?
Colobomas involving the retina result in vision loss in specific parts of the visual field. Large retinal colobomas or those affecting the optic nerve can cause low vision, which means vision loss that cannot be completely corrected with glasses or contact lenses.
What is Synechiae?
Synechiae are adhesions that are formed between adjacent structures within the eye usually as a result of inflammation.
What is cells and flare?
“Cell” is the individual inflammatory cells while “flare” is the foggy appearance given by protein that has leaked from inflamed blood vessels. This finding is commonly seen with uveitis, iritis, and after surgery … and actually seeing it can be challenging for the beginning ophthalmology residents.
What does a follicular cyst on a cow mean?
Fig 3: A thin-walled follicular cyst – these are usually easily felt per rectum by a Veterinarian. They can be associated with increased heat behaviour, but >95% of cases do not show and heat-type behaviour. Figure 4: A thicker-walled luteal cyst – cows with this type of cyst tend not to show any oestrus behaviour.
What is cystic ovarian disease in cattle?
Follicular Cystic Ovary Disease in Cattle. (Cystic follicles, “Bulling”) Follicular cystic ovary disease may be defined on a number of levels. Essentially, all signs relate to the disruption of the normal endocrine events of the estrous cycle, through the failure of ovulatory events.
What are the symptoms of a cyst on a cow?
In the latter cows, the clinical sign associated with cysts is the same as missed heats and anoestrus – cows that should be seen in heat are not. So again, good recording and management will identify affected cows and present them for veterinary examination.
What is the process of oogenesis in cattle?
The ovary produces the oocyte by a process called oogenesis. In contrast to spermatogenesis in the bull, which is continuous, oogenesis is cyclic. This cycle of oocyte development in cattle is called the estrous cycle and is typically 21 days in length.