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Background: Domestication and artificial selection have resulted in strong genetic drift, relaxation of purifying selection and accumulation of deleterious mutations. As a consequence, bovine breeds experience regular outbreaks of recessive genetic defects which might represent only the tip of the iceberg since their detection depends on the observation of affected animals with distinctive symptoms. Thus, recessive mutations resulting in embryonic mortality or in non-specific symptoms are likely to be missed. The increasing availability of whole-genome sequences has opened new research avenues such as reverse genetics for their investigation. Our aim was to characterize the genetic load of 15 European breeds using data from the 1000 bull genomes consortium and prove that widespread harmful mutations remain to be detected. Results: We listed 2489 putative deleterious variants (in 1923 genes) segregating at a minimal frequency of 5 % in at least one of the breeds studied. Gene enrichment analysis showed major enrichment for genes related to nervous, visual and auditory systems, and moderate enrichment for genes related to cardiovascular and musculoskeletal systems. For verification purposes, we investigated the phenotypic consequences of a frameshift variant in the retinitis pigmentosa-1 gene segregating in several breeds and at a high frequency (27 %) in Normande cattle. As described in certain human patients, clinical and histological examination revealed that this mutation causes progressive degeneration of photoreceptors leading to complete blindness in homozygotes. We established that the deleterious allele was even more frequent in the Normande breed before 1975 (>40 %) and has been progressively counter-selected likely because of its associated negative effect on udder morphology. Finally, using identity-by-descent analysis we demonstrated that this mutation resulted from a unique ancestral event that dates back to ~2800 to 4000 years. Conclusions: We provide a list of mutations that likely represent a substantial part of the genetic load of domestication in European cattle. We demonstrate that they accumulated non-randomly and that genes related to cognition and sensory functions are particularly affected. Finally, we describe an ancestral deleterious variant segregating in different breeds causing progressive retinal degeneration and irreversible blindness in adult animals. [ABSTRACT FROM AUTHOR]

A complete, thorough ophthalmic examination is essential in the clinical approach to equine ocular diseases. In the majority of cases and more than in most systems, an ophthalmic diagnosis can be achieved at the time of examination because most ocular structures can be visualised either directly or indirectly. This article describes examination protocol and the techniques, instruments and diagnostic procedures currently available to equine general practitioners. [ABSTRACT FROM AUTHOR]

This paper addresses treatment with acupuncture and Chinese herbal medicine of commonly encountered eye diseases in veterinary medicine, including blepharitis, entoprion, keratitis, conjunctivitis, glaucoma, and cataracts. An extensive list of local and distal acupuncture points along with clinical signs and Chinese herbal medicines used for a variety of eye diseases is included to aid the clinician. [ABSTRACT FROM AUTHOR]

The eyes are the bridge between Zang-Fu organs and the outside world. They connect with all meridians/channels of the body either directly or indirectly to form the eye unit. The close association of eye function with the Zang-Fu organs allows diagnosis of organ dysfunction through abnormal ocular clinical signs as well as specific lesion location on the eyes using the theories of Five Spheres, Eight Boundaries and Six Channels. This combined with diagnosis of body imbalance can greatly aid in the TCVM treatment of eye disorders. The extraordinary vessels, which include the Governing and Conception Vessels, Yin and Yang Qiao Mai and Yang Linking Vessel also connect to the eye unit and play a role in regulation of Yang and Yin Qi in the eyes. Internal and External pathogenic factors affect the entire body system which can manifest as ocular disease. By using the presenting ocular clinical signs and their association with particular channels and Zang-Fu organs, and discerning the overall TCVM pattern of imbalance in the body, practitioners are provided with a strong and effective approach to treating eye disorders with TCVM. [ABSTRACT FROM AUTHOR]

Objectives To describe the signalment, presence of systemic and/or ocular comorbidities, times to detected healing and probabilities of recurrence after diamond burr debridement ( DBD) of eyes with presumed corneal calcareous degeneration and secondary ulceration and/or ocular pain. Animals studied Twenty-six dogs with 42 eyes affected, 34 eyes treated with DBD. Methods A case series was conducted using medical records from a private veterinary ophthalmology referral practice. Dogs were included if they had white or gray corneal opacity consistent with corneal calcareous degeneration with either erosive or superficial ulceration and/or ocular pain in at least one eye and had at least one such eye treated with DBD. DBD was performed with a battery-operated handheld motorized burr (The Alger Company, Inc. Lago Vista, TX, USA), and a bandage contact lens was placed in the majority of eyes (30/34). Eyes were considered healed when the cornea was fluorescein negative, and there were no signs of ocular pain. Patient data (signalment, recurrence) were extracted from medical records. Results Dogs were first re-examined 7-62 days after treatment (median: 13 days). All DBD-treated eyes healed within 62 days (% healed: 100%; one-sided 97.5% CI: 90-100%, median: 14 days), 82% of eyes (28/34) were healed at first re-examination (median: 13 days after treatment), and all were healed by their second examination (median: 24 days). Of the 34 treated eyes, 11 were lost to follow up; 11 of the remaining 23 eyes recurred. Estimated 1-year recurrence probability was 58% (95% CI: 35-83%). Seven dogs had systemic disease; 7 had a history of prior ocular disease or intraocular surgery. Conclusions Diamond burr debridement is a safe and effective treatment for rapid resolution of superficial corneal ulceration and ocular pain secondary to presumed corneal calcareous degeneration in dogs. [ABSTRACT FROM AUTHOR]

Sudden acquired retinal degeneration syndrome ( SARDS) is one of the leading causes of currently incurable canine vision loss diagnosed by veterinary ophthalmologists. The disease is characterized by acute onset of blindness due to loss of photoreceptor function, extinguished electroretinogram with an initially normal appearing ocular fundus, and mydriatic pupils which are slowly responsive to bright white light, unresponsive to red, but responsive to blue light stimulation. In addition to blindness, the majority of affected dogs also show systemic abnormalities suggestive of hyperadrenocorticism, such as polyphagia with resulting obesity, polyuria, polydipsia, and a subclinical hepatopathy. The pathogenesis of SARDS is unknown, but neuroendocrine and autoimmune mechanisms have been suggested. Therapies that target these disease pathways have been proposed to reverse or prevent further vision loss in SARDS-affected dogs, but these treatments are controversial. In November 2014, the American College of Veterinary Ophthalmologists' Vision for Animals Foundation organized and funded a Think Tank to review the current knowledge and recently proposed ideas about disease mechanisms and treatment of SARDS. These panel discussions resulted in recommendations for future research strategies toward a better understanding of pathogenesis, early diagnosis, and potential therapy for this condition. [ABSTRACT FROM AUTHOR]

Objective To describe the tear ferning test ( TFT) in healthy horses and its correlation with other parameters for evaluating the ocular surface. Animals studied Thirty male and female adult healthy horses (60 eyes), of no defined breed. Procedures Tear sample was collected with a microcapillary tube, placed on the surface of a glass slide, and allowed to dry at room temperature. The crystallization pattern was classified according to Rolando ( Chibret International Journal Ophthamology, 1984; 2, 32). The program STEPanizer© stereology tool, version 1.0, was utilized for counting points on the digitally captured crystallization image. A conjunctival biopsy was performed. Results Tear ferning test was classified as Type I in 18 eyes (30%), Type II in 31 eyes (51.7%), and Type III in 11 eyes (18.3%), at a mean temperature of 27.3 ± 1.5 °C and relative humidity of 61.5 ± 5.7%. In the Type I crystallization, the count varied between 27 and 36 points (mean: 33.27 ± 2.40), in Type II between 22 and 31 points (25.42 ± 1.95), and in Type III between 13 and 25 points (16.82 ± 3.76). There was no statistical difference or correlation between the right and left eyes, nor was there a statistically significant influence ( P < 0.05) on TFT by the factors evaluated. The mean goblet cells values were 50 ± 11.4 cells/field. All samples showed the presence of lymphocytes, plasmocytes, and eosinophils. Conclusion Tear ferning test is easy to perform, without risks to the patient. Once standardized for horses, associated or not with the program STEPanizer© stereology tool, it is an additional method for evaluating the ocular surface. [ABSTRACT FROM AUTHOR]

A captive female square-lipped rhinoceros born in 1993 had been showing intermittent signs of bilateral conjunctivitis and conjunctival proliferation since 1998. Periodic improvement was noted, especially in winter, but overall the condition had deteriorated over the years. Treatment with various topical, intralesional, and systemic antibiotics and glucocorticosteroids was largely ineffective, as were repeated dewormings. No primary cause for these lesions was found in biopsies taken in 2000 and 2006, although a severe infiltrate of numerous eosinophils was observed in the latter. As the condition worsened, secondary corneal changes were noted, and eventually vision was lost due to proliferative conjunctival tissue. Aggressive resection of the proliferating tissue in 2013 restored vision and submitted biopsies yielded a diagnosis of severe allergic conjunctivitis, eosinophilic granuloma, and habronematid ( Habronema or Draschia) larval infection. As no other rhinoceros in the herd was affected, including two calves born to the patient who were in close contact with their mother, it was concluded the presentation was most likely due to a hypersensitivity reaction to the dead or dying larvae. Fly repellent is now regularly applied around the eye of this rhinoceros, and a protective face mask has been fitted. Ongoing periodic relapses are treated with oral ivermectin, topical antibiotics, and steroids. [ABSTRACT FROM AUTHOR]

Objective: Dogs, like humans, experience eye changes with aging: hardening and clouding of the lens and accumulated oxidative damage from UV sunlight. It has been debated whether such changes could be affecting the visual function of dogs. The objective of this study was to determine if autorefractometry could be used to measure visual function in dogs. Animals and Methods: Nine Beagle dogs (ages 1 to 14 years) were examined by a veterinary ophthalmologist and their eyes determined to be free of cataracts. Spherical equivalent refractive error was measured by handheld autorefractor (Welch Allyn SureSight) under both indirect and direct lighting conditions with five measurements per condition, per eye. Measures were repeated on three different days for each dog within six weeks. Nonparametric statistics were used to detect differences among lighting conditions and test days, and between eyes. Spearmen correlation assessed the visual measurement outcomes’ association with age. Results: There was no difference for day-to-day or between-eye measurements. Significantly, the Beagles showed a myopic shift with aging (average spherical equivalent ranged from plano to -3.00 diopters), suggesting that dogs become more near-sighted as they age (r = -0.48 and -0.73 under direct and indirect lights; p<0.05 both). Younger dogs were able to make larger accommodation changes from indirect light to direct light conditions, indicating a more flexible lens (r = -0.50, p<0.05). Conclusions: Although designed for humans, the hand-held autorefractor technique is applicable to dogs and sensitive to light conditions. The age-associated myopic shift could be expected to compromise dogs’ visual functions. [ABSTRACT FROM AUTHOR]

Tonometry is one of the basic diagnostic tests used for the diagnosis of glaucoma and uveitis in veterinary ophthalmology. The Icare® Rebound Tonometer which is a new tonometric device has been shown to be useful in a wide range of species. Eyes (n = 48) of 24 Simmental and Montafon calves with a mean age of 7.5 weeks (2–16 weeks), male and female, were subjected to intraocular pressure (IOP) measurement using the Icare® Rebound Tonometer with calves standing and in lateral recumbency. The mean IOP was measured as 9.02 ± 2.38 mmHg in the right eye and 9.08 ± 2.55 mmHg in the left eye. No age-related change was found in intraocular pressure of the calves between 2 and 16 weeks of age. No difference in IOP values was observed between Simmental and Montafon calves. Body position had no effect on IOP in calves. The Icare® Rebound Tonometer was shown to be a suitable diagnostic device for IOP measurement in calves. [ABSTRACT FROM AUTHOR]

Scleral rings or os opticum were collec ted from the Kuttanad ducks both in prehatch and posthatch period and for comparis on from adult B antam fowl, White Leghorn, Green-winged Macaw, Tur key and Kadaknath. The ring s were stained by Alizarin red 'S' technique. The ring was present in the substance of sclera immediately bordering the cornea at corneo-scleral junction. These scleral rings were formed by small scale like osseous plates known as scleral ossicles which were nine in number, without overlapping in 14th day old embryo. From 21st day of incubation the number increased to 15 and remained same up to 24th week of posthatch life with varying degree of overlapping. The number of osseous plates in scleral ring varied among the birds as 14 in Bantam fowl, 13 in White Leghorn chicken, 11 in Green-winged macaw, 17 in turkey and 15 in Kadaknath. Diameter of the scleral ring was positively correlated to the size of the eyeball with the smallest diameter being observed in the case of Bantam fowl and the largest in Turkey. [ABSTRACT FROM AUTHOR]

This study was carried out to determine morphological structures of Anatolian Shepherd dog eye to compare with other animals. This important sensory organ from five adult male dogs were investigated by light microscopic and scanning electron microscopic analyses. Anatolian Shepherd dog cornea is about 435 (center) to 501 (periphery) pm thick. The dense pigmentation observed in the anterior and posterior iridal epithelium. The ciliary cleft of the iridocorneal angle was not large and well-developed. The ciliary processes, another component of the ciliary body, formed the conspicuous bundles. In conclusion, it is considered that the description of the morphological properties of both the iridocorneal region and the ciliary body would contribute to the interpretation of the functional correlation, thus to future experimental studies to be conducted in this field. [ABSTRACT FROM AUTHOR]

The aim of this article was to describe Descemet's membrane detachment ( DMD) following phacoemulsification in five equine eyes and to review the human literature on this topic. In the last decade, there has been increased reporting of DMD in the human literature, in particular following cataract surgery. The natural history of DMD remains unknown and although various medical and surgical treatments have been advocated there is no recognized 'gold standard' treatment for DMD. This case series reports the diagnosis of DMD in four horses (5 eyes) in association with phacoemulsification surgery. The diagnosis of DMD in these patients was made intra-operatively, postoperatively or on subsequent histopathological examination. The surgical reports, photographic or video recordings, and ultrasound data were evaluated and possible factors associated with the pathophysiology of DMD are discussed. This is the first description of DMD in the veterinary literature, and the authors believe that DMD might hitherto have been overlooked in veterinary ophthalmology due to a lack of awareness of the condition. The possible causes, clinical signs, and treatment of DMD as described in the human literature are also reviewed. [ABSTRACT FROM AUTHOR]

Background: Scleral cross-linking (CXL) is a novel attempt to slow down the axial elongation process in animal eyes. As a natural CXL reagent, genipin would be also effective for the prevention of myopia process. Thus, the present study was designed to evaluate the effects of scleral cross-linking using genipin on the form-deprivation (FD) myopia process of guinea pigs. Methods: Twenty-seven 3-week-old pigmented guinea pigs were randomly divided into three groups. Group A (n = 8) is the untreated control group. Group B (n = 8) is the FD control group, where all eyes were induced with monocular FD for 21 days. In Group C (n = 11), a sub-Tenon injection of 0.10 mL 0.50 % genipin was performed on FD eyes at day 0, 7 and 14 during the 21-day monocular FD. The ocular refraction, axial length, biomechanical test and light and electron microscopy were measured on all eyes to check the efficacy and safety of this scleral CXL technique. Results: Compared with Group A, significant increases in myopic refractive errors, axial elongation and reductions of scleral fibril diameter and density were observed in the 21-day FD eyes of Group B (P < 0.05). In Group C, the scleral CXL resulted in less myopia and axial elongation as compared with Group B (P < 0.05); a significant thickening of scleral fibrils was found after sub-Tenon injections of genipin; no histological damage on the retina or choroid was observed in Group C at the end of this study. Conclusions: The FD myopia in guinea pig eyes was effectively blocked by the scleral CXL using sub-Tenon injections of genipin. No histological damage was found on the retina or choroid of these treated eyes. Further studies are needed to examine the long-term efficacy and safety of this CXL technique. [ABSTRACT FROM AUTHOR]

Seventeen adult captive American flamingos ( Phoenicopterus ruber ruber) (34 eyes) underwent a complete ocular examination, including assessment of menace response, pupillary light reflexes, dazzle reflex, palpebral and corneal reflexes, fluorescein staining, slit-lamp biomicroscopy, and direct ophthalmoscopy. Birds were randomly assigned to one of 2 groups for tear production and intraocular pressure measurements. Tear production was measured by modified Schirmer tear test I (n = 9 birds) or phenol red thread test (n = 8 birds), and intraocular pressure was measured indirectly by applanation (Tonopen-XL) (n = 9 birds) or rebound (TonoVet) (n = 8 birds) tonometry. Conjunctival swab samples were taken from one randomly selected eye of all 17 birds to identify surface ocular microbial flora via aerobic bacterial culture. Additionally, 3 of the 17 birds were anesthetized for bilateral B-mode ocular ultrasonography examination to obtain axial globe measurements. Results showed that the menace response and dazzle reflex were absent in all birds. Sixteen of the 17 birds were free of significant ocular disease; a small cataract and pigment on the anterior lens capsule were noted in one eye of one bird. Mean ± SD tear production was 12.3 ± 4.5 mm/min (range, 4-20 mm/min) for modified Schirmer tear test I and 24.2 ± 4.4 mm/15 s (range, 14-30 mm/15 s) for phenol red thread test. Modified Schirmer tear test I measurements were significantly lower than phenol red thread measurements ( P < .001). Mean intraocular pressure was 16.1 ± 4.2 mm Hg (range, 7-22 mm Hg) for Tonopen and 9.5 ± 1.7 mm Hg (range, 7-13 mm Hg) for TonoVet. Tonopen measurements were significantly higher than TonoVet measurements ( P < .001). An Enterococcus species (9/17 eyes; 53%) and a gram-positive coccus (7/17 eyes; 41%) were the bacteria most commonly isolated from conjunctival swab samples. Mean B-mode ultrasonographic globe measurements of 6 eyes (3 birds) were axial globe length, 13.8 ± 0.16 mm; anterior chamber depth, 1.75 ± 0.05 mm; lens thickness, 4.6 ± 0.06 mm; vitreous body depth, 6.95 ± 0.10 mm; and pecten dimensions, 5.1 ± 0.38 mm length, 2.2 ± 0.14 mm width. In summary, the prevalence of ocular lesions was low in this population of captive American flamingos. Results obtained from 2 types of tear and intraocular pressure measurement tests were significantly different, indicating that a single type of each diagnostic test should be consistently used. A modification of the standard Schirmer tear test or use of phenol red thread test is recommended due to the small flamingo eye. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To evaluate the use of rebound and applanation tonometry for the measurement of intraocular pressure (IOP) and to assess diurnal variations in and the effect of topical anesthesia on the IOP of healthy inland bearded dragons (Pogona vitticeps). ANIMALS: 56 bearded dragons from 4 months to II years old. PROCEDURES: For each animal following an initial ophthalmic examination, 3 IOP measurements were obtained on each eye between 9 AM and 10 AM, I PM and 2 PM, and 5 PM and 7 PM by use of rebound and applanation tonometry. An additional measurement was obtained by rebound tonometry for each eye in the evening following the application of a topical anesthetic to evaluate changes in the tolerance of the animals to the tonometer. Descriptive data were generated, and the effects of sex, time of day, and topical anesthesia on IOP were evaluated. RESULTS: Bearded dragons did not tolerate applanation tonometry even following topical anesthesia. Median daily IOP as determined by rebound tonometry was 6.16 mm Hg (95% confidence interval, 5.61 to 6.44 mm Hg).The IOP did not differ significantly between the right and left eyes. The IOP was highest in the morning, which indicated that the IOP in this species undergoes diurnal variations. Topical anesthesia did not significantly affect IOP, but it did improve the compliance for all subjects. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that rebound tonometry, but not applanation tonometry, was appropriate for measurement of IOP in bearded dragons. These findings provided preliminary guidelines for IOP measurement and ophthalmic evaluation in bearded dragons. [ABSTRACT FROM AUTHOR]

Glaucoma may be either primary (inherited) or secondary owing to other intraocular pathology. Clinical signs can be variable but the main consistent risk factor for glaucoma is elevated intraocular pressure. Both medical and surgical treatment options exist although the long-term prognosis is often poor, especially for primary glaucoma, with many eyes ultimately needing to be removed. [ABSTRACT FROM AUTHOR]

Purpose To perform a descriptive investigation of the red-eared slider turtle ( Trachemys scripta elegans) eye, performing selected ophthalmic diagnostic tests with the aim of establishing normal reference values for this species. Method Thirty adult healthy red-eared slider turtles were used to establish normal ophthalmic test values in this investigation. Selected ophthalmic tests included: collection of material for bacterial culture analysis, esthesiometry, intraocular pressure ( IOP), A- and B-mode ultrasonic biometry, fundus photography, and central corneal thickness ( CCT). Results and discussion Normal parameters found for the ocular diagnostic tests were: esthesiometry: 5.84 ± 0.48 cm; IOP: 5.42 ± 1.70 mmHg; CCT: 154.5 ± 0.14 μm; palpebral fissure length: 9.71 ± 0.55 mm; modified Schirmer tear test: 2.55 ± 3.4 mm; globe axial length: 7.60 ± 0.23 mm; anterior chamber depth: 0.76 ± 0.23 mm; lens axial length: 2.45 ± 0.28 mm; vitreous chamber depth: 4.31 ± 0.42 mm. An avascular retinal pattern with nerve fibers radiating from the small white circular optic disk was observed. None of the animals had a conus papillaris. The most frequent bacteria found were Bacillus spp. (33.33%) followed by Proteus vulgaris (20.69%) and Staphylococcus aureus (18.39%). No significant differences between left and right eyes or genders were found for any of the results. Reference data and morphologic observations obtained in this investigation might help veterinary ophthalmologists to diagnose ocular diseases in the red-eared slider turtle. [ABSTRACT FROM AUTHOR]

A 3-year-old neutered male Scottish Fold cat weighing 4.4 kg presented with a corneal laceration of the left eye. The cornea was not perforated, as determined by a Seidel test. Vision was normal. The defect was successfully repaired using deep lamellar keratectomy and application of a tectonic graft, using glycerinpreserved canine corneal stroma. Thirtytwo days after surgery, corneal neovascularization surrounding the graft was evident. Fortysix days after surgery, part of the graft was slightly cloudy but the cornea was mostly clear. Therefore, canine glycerinpreserved corneal stroma may be suitable for use in tectonic heterologous grafting to repair deep lamellar keratectomy during keratoplasty in cats. [ABSTRACT FROM AUTHOR]

Background: The squamous cell carcinoma (SCC) is the second most common cancer in the oral epithelium of dogs and rarely involves the retrobulbar area. The diagnosis is confirmed with cytological and histopathological exam. Faced with the unusual occurrence of retrobulbar tumors in dogs, we report a case of SCC in the left maxilla, with ipsilateral retrobulbar metastasis, and also highlight clinical aspects of the neoplasia, exams, early diagnosis and therapeutic possibilities. Case: A male dog, 17 years old, with a history of visual loss, enlargement of left eye and prostration after 25 days of a dental treatment. The patient had exophthalmia of the left eye with mild lateral deviation, meibomitis, lagophthalmos, moderate conjunctival hyperemia and episcleral congestion, protrusion of the third eyelid, epiphora, moderate purulent discharge, paracentral corneal degeneration, absence of pupillary reflex to light (direct and consensual) and presence of immature cataract. The Schirmer test and intraocular pressure were normal, as well as complete blood count and biochemical profile. Due to the testy temperament of the animal, the intraoral examination was limited to two-thirds of the jaw in the first appointment. Ocular vitreous ultrasound was performed showing moderate amount of membranous and punctate echoes, as well as medium-high reflectivity were present in all meridians evaluated, suggesting hemorrhagic-inflammatory process. In the retrobulbar space image of contours were poorly defined, measuring approximately 35.2 mm, with a heterogeneous echotexture and mixed echogenicity, suggestive of neoplasm or abscess. The animal was anesthetized for cytological evaluation. Absence of left maxillary molars teeth, ulceration area and a maxillae nodule was observed ipsilateral to abnormal eye. This node had one centimeter in diameter, was reddish, ulcerated, friable and adhered. The material was collected for histopathology, which confirmed the diagnosis of undifferentiated SCC, with a primary focus in the oral cavity. Discussion: Exophthalmia can be a common clinical sign for ophthalmic and oral neoplasias and should be differentiated from secondary exophthalmia glaucoma, injuries and abscesses, granulomas, cysts, orbital cellulitis. It may also be the source of oral or salivary glands infections and systemic diseases. In this case, the clinical signs and history of previous dental treatment, ocular ultrasonography was performed to differentiate abscess from neoplasia, and also to verify the affected area. It was conclude that the retrobulbar neoplasia was secondary to oral squamous cell carcinoma due to the malignant neoplasia had keratinocyte origin, which is normally found in oral epithelium cells, however this types of cells is not found in retrobulbar area. Additionally to support our statement primary retrobulbar neoplasia has frequently low metastatic capacity to surrounding organs. The loss of visual acuity, probably was consequence of optic nerve compression, which also may led to impairment of the pupillary reflex of afferent pathway. As most retrobulbar neoplasia results from metastasis, clinical examination of adjacent regions is essential, as well as the use of additional exams to assist in the search for primary tumor and exclusion disorders that can demonstrate the same clinical signs. [ABSTRACT FROM AUTHOR]

The article discusses the impact of subconjunctival transplantation of limbal stem cell allografts on the hematology factors in dogs. Topics discussed include the study proving the potential of the cornea as a major source of stem cells for medicinal use, the study involved dogs suffering from chronic thinning of the central cornea, and results proving that the limbal stem cell allografts did not change haematology factors in dogs.

Vitamin D is an important hormone in vertebrates. Most animals acquire this hormone through their diet, secondary to exposure to ultraviolet B (UVB) radiation, or a combination thereof. The objectives for this research were to evaluate the clinical and physiologic effects of artificial UVB light supplementation on guinea pigs (Cavia porcellus) and to evaluate the long-term safety of artificial UVB light supplementation over the course of six months. Twelve juvenile acromelanic Hartley guinea pigs were randomly assigned to one of two treatment groups: Group A was exposed to 12 hours of artificial UVB radiation daily and Group B received only ambient fluorescent light for 12 hours daily. Animals in both groups were offered the same diet and housed under the same conditions. Blood samples were collected every three weeks to measure blood chemistry values, parathyroid hormone, ionized calcium, and serum 25-hydroxyvitamin D3 (25-OHD3) levels. Serial ophthalmologic examinations, computed tomography scans, and dual energy x-ray absorptiometry scans were performed during the course of the study. At the end of the study the animals were euthanized and necropsied. Mean ± SD serum 25-OHD3 concentrations differed significantly in the guinea pigs (p<0.0001) between the UVB supplementation group (101.49±21.81 nmol/L) and the control group (36.33±24.42 nmol/L). An increased corneal thickness in both eyes was also found in the UVB supplementation compared to the control group (right eye [OD]: p<0.0001; left eye [OS]: p<0.0001). There were no apparent negative clinical or pathologic side effects noted between the groups. This study found that exposing guinea pigs to UVB radiation long term significantly increased their circulating serum 25-OHD3 levels, and that this increase was sustainable over time. Providing guinea pigs exposure to UVB may be an important husbandry consideration that is not currently recommended. [ABSTRACT FROM AUTHOR]

Objective To compare the effects of alfaxalone and propofol on intraocular ( IOP) pressure in the canine eye. Animals studied Twenty-three healthy adult dogs. Procedures Dogs were randomized to receive intravenous propofol ( n = 11) or alfaxalone ( n = 12) until loss of jaw tone, 20 min after intravenous premedication (acepromazine 0.02-0.03 mg/kg and hydromorphone 0.05-0.1 mg/kg). IOP was measured at baseline ( BL), 20 min postpremedication (postpremed), loss of jaw tone (postinduct), and immediately following orotracheal intubation (postintub). Between- and within-treatment effects were analyzed with two-way and one-way repeated measures ANOVA with Bonferroni's post hoc test, respectively. P < 0.05 was considered significant. Results No significant IOP differences were detected between alfaxalone or propofol groups at any time point ( P > 0.05). Propofol: IOP did not change between BL (15.5 ± 2.7 mmHg) and postpremed (16.2 ± 3.6 mmHg, P > 0.05), or postinduct (19.1 ± 5.2 mmHg) and postintub (21.0 ± 4.6 mmHg, P > 0.05), but differed significantly between BL and postinduct ( P < 0.0001), and postintub ( P < 0.0001). Alfaxalone: IOP did not change between BL (15.7 ± 2.8 mmHg) and postpremed (15.3 ± 4.1 mmHg, P > 0.05), or postinduct (19.2 ± 4.9 mmHg) and postintub (20.5 ± 4.5 mmHg, P > 0.05), but differed significantly between BL and postinduct ( P < 0.01), and postintub ( P < 0.0001). Conclusions These data show a potentially clinically significant increase in IOP following induction with propofol or alfaxalone, but no difference between agents. [ABSTRACT FROM AUTHOR]

Objective The aim of this study was to investigate the development of aqueous tear production and intraocular pressure in healthy canine neonates between 2 and 12 weeks of age. Animals One litter, consisting of 8 healthy Beagle dogs-four males and four females-was used. Procedures Between the age of 2 and 12 weeks, tear production and intraocular pressure were measured weekly in both eyes. Tear production was measured by Schirmer tear test, before ( STT1) and after ( STT2) topical anesthesia and drying of the conjunctival sac. Intraocular pressure ( IOP) was measured using a rebound tonometer. As no significant differences existed between left and right eye measurements ( STT1, STT2, and IOP) at all time points, only right eye measurements were further analyzed. Results STT1, STT2, and IOP values increased significantly until the age of 9 weeks for STT1, until the age of 10 weeks for STT2, and until the age of 6 weeks and again between 10 and 11 weeks of age for IOP. IOP decreased significantly between 11 and 12 weeks of age. There were no significant differences in STT1, STT2, and IOP between males and females, except for IOP at 10 and 12 weeks of age. No significant correlation was demonstrated between body weight and STT1 or STT2. Conclusions STT1, STT2, and IOP values increased significantly in the first weeks after birth. The results of this study indicate that separate reference values for tear production and intraocular pressure need to be established for neonatal dogs. [ABSTRACT FROM AUTHOR]

Objective To determine the effects of the administration of subconjunctival 1% atropine ( SA), topical 1% atropine ( A), 0.5% tropicamide ( T), 1% homatropine ( H), 10% phenylephrine ( P), and 2% ibopamine ( I) on intraocular pressure ( IOP), pupil diameter ( PD), ruminal motility ( RM) and intestinal motility ( IM) in sheep. Animal studied Ten spayed ewes of Santa Inês breed. Procedures Six experiments were performed separately at 1-week intervals. One eye was randomly selected and received one drop of A, T, H, P, I, or subconjunctival injection of atropine at 8 a.m. On the following days, IOP and PD were evaluated every 8 h until the pupil returned to its normal diameter. Ruminal motility and intestinal motility were evaluated only within the first 13 h. Results The IOP did not change significantly in the treated eyes compared with the control eyes and baseline at any time point ( P > 0.05). A longer-lasting pupil dilation was observed after the administration of A (96 h), SA (79 h), H (24 h), and T (24 h). Within the first 30 min after treatment, RM and IM decreased, by 78% and 82% ( H), 76% and 86% ( SA), 46% and 58% ( A), and 62% and 70% ( T) ( P < 0.001), respectively, with a tendency to return to baseline values following 13 h of drug administration. Both 10% phenylephrine and 2% ibopamine did not have any effect on the parameters evaluated ( P > 0.05). Conclusions Topical and subconjunctival 1% atropine, 0.5% tropicamide, and 1% homatropine significantly reduced RM and IM, and induced pupil dilation but did not change IOP in eyes of healthy sheep. The sympathomimetics phenylephrine (10%) and ibopamine (2%) did not change the parameters evaluated. [ABSTRACT FROM AUTHOR]

Objective To compare the intraocular pressure ( IOP) measurements from two applanation tonometers ( Tono- Pen XL® and Accu Pen®) in normal and diseased canine eyes (including corneal disease, cataract, glaucoma, uveitis, and noninflammatory intraocular disease) and evaluate the associations among the central corneal thickness ( CCT), IOP measurements, and age. Animals studied Sixty-eight normal and 191 diseased eyes. Procedure A topical anesthetic agent was applied to each eye. One minute later, IOP was measured with the Tono- Pen XL® and then the AccuPen®, and then CCT was measured with an ultrasonic pachymeter. Measurements for the right eye were always taken first. Results The Tono- Pen XL® successfully measured IOP in all eyes, whereas the Accu Pen® registered measurements in only 98.4% of diseased eyes. The Accu Pen® measurements were significantly lower than the Tono- Pen XL® measurements in both normal and diseased eyes. The CCT did not affect the Tono- Pen XL® or AccuPen® measurements in normal or diseased eyes. Spearman's correlation coefficient by rank analysis of CCT and IOP yielded correlation coefficients ( r) of 0.144 and 0.101 for the Tono- Pen XL®, and 0.108 and 0.175 for the AccuPen® in normal and diseased eyes, respectively. In normal canine eyes, age correlated inversely with the CCT ( r = −0.128) and IOP as measured using the Tono- Pen XL® ( r = −0.446) and AccuPen® ( r = −0.427). Conclusions The AccuPen® measurements were slightly but significantly lower than the Tono- Pen XL® measurements in both normal and diseased canine eyes. The CCT affected the results of neither tonometer regardless of disease, while both IOP and CCT tended to decrease with age in normal eyes. [ABSTRACT FROM AUTHOR]

Electroretinography (ERG) in the form of full-field, flash ERG is the most commonly used technique in veterinary ophthalmology for diagnosing the functioning of the outer retina. Under light stimulation spatially distributed different cell types within the retina produce time-varying electric responses. These are recorded in the form of ERG traces consisting of a series of positive and negative wavelets. The possibility of selective stimulation of individual types of retinal cells and the analysis of constituent components of ERGs are the basis for determining the source of abnormalities and diagnosis of various types of dysfunction. In many cases, the ERG allows diagnosis of hereditary retinal disorders in dogs before the appearance of behavioural and ophthalmoscopic symptoms. This review is an introduction to the electrophysiology of vision, intended for small animal practitioners, and aimed at presenting the benefits of ERG for early ophthalmic diagnostics in dogs. [ABSTRACT FROM AUTHOR]