The TFT is appropriate for dogs and can be performed using the three suggested sampling methods, with a higher frequency of Type I and Grade 1. Thus, it is possible to use both grading scales in the classification of tear ferning in dogs.

No abstract

The scleral ossicle rings function has been related to mechanical protection, muscle fixation, support for eyeball shape and visual accommodation. There are few morphobiometric reports on these rings in different Testudines species, and we performed ultrasound (US) and computed tomography (CT) of the scleral ossicle rings in one green turtle (Chelonia mydas), one black-bellied slider (Trachemys dorbigni) and one red-footed tortoise (Chelonoidis carbonarius). The US and CT of the ossicle rings were performed for anatomical identification. The thickness, density, width, and diameters of each ring were measured. The US and CT of the scleral ossicle rings of three animals showed single and continuous circular structures, located in the anterior pole. These structures were easily observed in C. mydas, whose rings were the biggest, thickest and widest. The T. dorbigni CT presented decreased dimensions and the ossicles were the most difficult to identify. Bone density in the superior region was greater than in the inferior of each ring in all animals. Non-invasive imaging exams are good tools to study the anatomy of the ocular skeleton. The scleral ossicle rings of the three specimens presented general morphological similarities and CT enabled visualizing a greater number of details of the ring bone morphology.

To compare tear electrolytes and tear crystallization patterns in birds and reptiles, tears were sampled by Schirmer tear test from 10 animals each of Ara ararauna, Amazona aestiva, Tyto alba, Rupornis magnirostris, Chelonoidis carbonaria , and Caiman latirostris , and 5 of Caretta caretta . The aliquots were pooled to assess concentrations of total protein, chloride, phosphorus, iron, sodium, potassium, calcium, and urea. For the tear ferning test, samples of each species were observed under a polarized light microscope at room temperature and humidity. Crystallization patterns were graded according Rolando and Masmali scales. There was more total protein and urea in owl and sea turtle tears, respectively, than in the other animals tested. Electrolyte balance was similar for all species, with higher sodium, chloride, and iron. In birds, Rolando-scale grades of tear crystallization patterns ranged from I to II, and from 0 to 2 using the Masmali scale; in reptiles, grades were II to IV (Rolando) and 2 to 4 (Masmali). Crystallization arrangements of some species had higher scores, as caimans and sea turtles, possibly due to different the tear composition. Marine and lacustrine species presented higher. The ionic balance of lacrimal fluids of birds and reptiles was similar to that in humans, with higher values of sodium and chloride. However, a similar tear composition did not influence the crystal morphology. Crystallization classification suggested that higher grades and types are due to the different microelements present in the tears of wild species.