A recessive CLN3 variant is responsible for delayed-onset retinal degeneration in Hereford cattle.

Thirteen American Hereford cattle were reported blind with presumed onset when ~12-mo-old. All blind cattle shared a common ancestor through both the maternal and paternal pedigrees, suggesting a recessive genetic origin. Given the pedigree relationships and novel phenotype, we characterized the ophthalmo-pathologic changes associated with blindness and identified the responsible gene variant. Ophthalmologic examinations of 5 blind cattle revealed retinal degeneration. Histologically, 2 blind cattle had loss of the retinal photoreceptor layer. Whole-genome sequencing (WGS) of 7 blind cattle and 9 unaffected relatives revealed a 1-bp frameshift deletion in ceroid lipofuscinosis neuronal 3 (CLN3; chr25 g.26043843del) for which the blind cattle were homozygous and their parents heterozygous. The identified variant in exon 16 of 17 is predicted to truncate the encoded protein (p. Pro369Argfs*8) battenin, which is involved in lysosomal function necessary for photoreceptor layer maintenance. Of 462 cattle genotyped, only blind cattle were homozygous for the deletion. A query of WGS data of > 5,800 animals further revealed that the variant was only observed in related Hereford cattle. Mutations in CLN3 are associated with human juvenile neuronal ceroid lipofuscinosis (JNCL), or Batten disease, which results in early-onset retinal degeneration and lesions similar to those observed in our cases. Our data support the frameshift variant of CLN3 as causative of blindness in these Hereford cattle, and provide additional evidence of the role of this gene in retinal lesions, possibly as a model for human non-syndromic JNCL.

Resident Selection Criteria in Veterinary Medicine.

With the continued rise of interest and need for veterinary specialists, information regarding optimal selection criteria for successful residency candidates has been lacking in veterinary medicine. A 28-question online survey was developed to determine prioritized resident selection criteria, the importance of formal interviews, and residency supervisor satisfaction with the current selection process. This survey was sent to all programs listed by the Veterinary Internship and Residency Matching Program (VIRMP) for the 2019-2020 program year. Overall, the most important aspects of the residency application process were (1) letters of recommendation, (2) performance during the interview, (3) personal contact/recommendation from a colleague, (4) personal statement, and (5) demonstrated interest in the residency specialty. While measures of academic performance including GPA and veterinary class rank may play a role in sorting of candidates in more competitive specialties, this does not necessarily exclude them from the ranking process. This information should be helpful to candidates and program directors alike in understanding the success of the current residency candidate selection process.

A remote fluorescein staining and photography protocol for monitoring of ulcerative keratitis in small animal patients: A pilot study.

OBJECTIVE: To describe a protocol for corneal ulcer monitoring utilizing daily fluorescein staining and evaluation of owner-acquired anterior segment images. ANIMAL STUDIED: Nine client-owned small animal patients (eight dogs, one cat) diagnosed with superficial corneal ulcers at the University of Georgia Veterinary Capitalize Hospital. PROCEDURE(S): In addition to routine ulcer therapy, patients were discharged with supplies to perform daily fluorescein staining including a Quikvue® cobalt blue light camera adapter. Fluorescein staining was performed daily, photographs and/or videos were acquired at home by the patient's owner(s), and images were analyzed daily by trained personnel. In-house examinations were performed weekly and within 24 h after the ulcer had appeared healed on photographs. RESULTS: All (9/9) owners were able to take interpretable photographs. The majority (6/9) of patients had images successfully detailing their ulcer healing progress. One (1/9) patient appeared healed on images, but on subsequent examination had persistent ulceration covered by third eyelid elevation. Two (2/9) patients had persistent ulceration, consistent on both images and examination, but exited the study prematurely prior to ulcer healing. CONCLUSIONS: Remote fluorescein staining and image evaluation can be considered as an adjunct for monitoring ulcer healing but should not be used alone or as a substitute for ophthalmic examinations. Ulcers under the third eyelid have potential to be missed on image evaluation alone.

Ophthalmic Disease and Screening in Breeding Dogs.

This article describes the history and infrastructure associated with canine breed-related eye screening and certification by Diplomates of the American College of Veterinary Ophthalmologists. Some of the common or otherwise particularly problematic specific inherited ophthalmic conditions are discussed.

Examination of Motivational Influences on Clinical-Year Veterinary Students' Career Decisions.

The purpose of this study was to identify motivations for fourth-year veterinary students to choose future career paths based on post-graduation employment or post-graduation education. Approximately 500 students from four institutions were invited to participate in an online survey. Surveys were based on the cognitive evaluation theory, a minitheory within the self-determination macrotheory framework developed by Deci and Ryan. Intrinsic motivational factors were categorized by autonomy, competence, and relatedness, and extrinsic motivators were categorized by environmental and interpersonal factors. Students pursuing post-graduation education have intrinsic motivators that aligned with competence and were extrinsically motivated by a mentor, while students interested in post-graduation employment had intrinsic motivators that were more focused on autonomy with extrinsic motivational influences of debt/finances and geographic location.

Single instead of triplicate intraocular pressure measurements in dogs do not substantially lower accuracy and precision but do slightly reduce statistical power.

OBJECTIVE: To compare single and triplicate applanation tonometry values across previous intraocular pressure (IOP) studies in dogs. ANIMALS: 116 ophthalmologically normal dogs. PROCEDURES: Triplicate IOP readings (n = 1432) from studies evaluating effect of anesthetic protocols were analyzed to estimate a range of probable differences between averaged triplicate and first, averaged and lowest, and first and lowest IOPs. The decrease in variability with triplicate measurements and the magnitude of effects on statistical power were quantified. RESULTS: The 2.5th to 97.5th interpercentile range for differences of averaged triplicate values minus first IOP readings was -3 to 2.7 mm Hg; for averaged minus lowest: 0 to 3.7 mm Hg; for first minus lowest: 0 to 5 mm Hg. The 95% prediction interval for differences in study group means (n = 160 groups, n = 5 to 11 eyes per group) based on averaged minus first measurements was -1.0 to 0.9 mm Hg with associated SDs reduced by 4% on average. Analysis of previous studies using averaged instead of first IOP values resulted in minimal decreases in SEs of 3-9% (0.03 to 0.09 mm Hg). Of 11 comparisons found significant with averaged data, 2 (18%) were found nonsignificant with first measurements. Of 96 comparisons found nonsignificant with averaged data, 3 (3%) were found significant with first measurements. CLINICAL RELEVANCE: With applanation tonometry in ophthalmologically normal dogs, no clinically meaningful difference was found between the first, lowest, or averaged triplicate IOP measurements, but the first reading has a larger variance and hence will result in lower statistical power.

Effect of topical non-steroidal anti-inflammatory drugs on healing times and complications in dogs with spontaneous chronic corneal epithelial defects.

BACKGROUND: Little is published regarding topical NSAID effect on corneal healing in dogs. This retrospective cohort study aimed to compare healing times and complications in dogs with spontaneous chronic corneal epithelial defects (SCCED) treated with and without topical non-steroidal anti-inflammatory drugs (NSAID). METHODS: Medical records of 66 dogs (71 eyes) diagnosed with SCCED between 2008 and 2019 were included. Eyes were divided into: (1) those receiving topical NSAIDs (n = 33) versus (2) those not receiving topical NSAID (n = 38). Follow-up until healed, such as comfortable eye, negative fluorescein stain was required. Use of topical or systemic anti-inflammatories outside of NSAID or presence of ocular disorders or systemic endocrinopathies that may contribute to delayed healing resulted in study exclusion. RESULTS: Healing times were significantly longer in eyes that received topical NSAID (p = 0.008), however, the use of more topical medications for treatment was also associated with longer healing times (p = 0.001). The majority of eyes in the NSAID group received multiple medications, compared to the non-NSAID group, so it was not possible to separate the effects of NSAID from a number of medications. Complications occurred in three eyes of three dogs within the NSAID group. CONCLUSIONS: In these canine SCCED eyes, the use of more topical medications, including NSAID, was associated with significantly delayed healing time.

Incidence and risk factors for surgical site infection following enucleation in dogs.

Introduction: Surgical site infections (SSI) increase morbidity, increase treatment costs, and can delay onset of necessary adjunctive therapy. The goal of this retrospective study was to determine the incidence of and risk factors of SSI after enucleation in dogs. Methods: Medical records were searched at one veterinary teaching hospital and identified 280 dogs that underwent enucleation and had an adequate follow-up to assess SSI. Multiple preoperative (e.g., reason for enucleation), peri-operative (e.g., surgical approach and surgeon experience level), and post-operative (e.g., use of post-operative antibiotics or anti-inflammatory medications) variables were assessed as risk factors for development of SSI. Results: The incidence of SSI after enucleation was 5%, and no risk factors for SSI were identified. Dogs that received cephalexin as a prophylactic post-operative antibiotic were statistically more likely to develop SSI versus those that received a different post-operative antibiotic (p = 0.045). However, the clinical significance of this finding is unclear as administration of prophylactic post-operative antibiotics overall did not reduce the risk of SSI in the population evaluated here. Discussion: No risk factors were identified to guide clinical decision-making for prevention of SSI. Additionally, the results do not support the use of prophylactic antibiotics after enucleation in dogs.

The effect of xylazine on intracranial pressure in anesthetized and standing horses.

OBJECTIVE: To determine the effect of xylazine on intracranial pressure (ICP) in standing compared to isoflurane-anesthetized horses. DESIGN: Prospective, crossover study design. SETTING: University Teaching Hospital. ANIMALS: Six adult horses donated to the University. Horses were determined to be healthy via physical examination, complete blood count, and neurological evaluation. INTERVENTIONS: Horses were anesthetized, maintained on isoflurane in oxygen in left lateral recumbency, and ventilated to normocapnia. Horses were instrumented for intraparenchymal measurement of ICP, invasive blood pressure, pulse oximetry, and end tidal gas analyzer. Xylazine 1 mg/kg was administered IV and ICP, systolic arterial pressure, mean arterial pressure (MAP), diastolic arterial pressure, and heart rate were recorded and cerebral perfusion pressure (CPP) was calculated for the following 15 minutes. Twenty-four to 36 hours following anesthetic recovery, xylazine 1 mg/kg was administered IV and ICP, heart rate, and Doppler blood pressure (BPdop) on the tail were monitored for 15 minutes. MEASUREMENTS AND MAIN RESULTS: There was a decrease in ICP following administration of xylazine in anesthetized horses (P < 0.003) but not standing horses (P = 0.227). There was an increase in systolic arterial pressure, MAP, diastolic arterial pressure (P < 0.001), and BPdop (P = 0.001) following administration of xylazine. As a result, CPP increased in anesthetized horses (P < 0.03). There was a negative association between ICP and MAP in anesthetized horses (P = 0.007) but not ICP and BPdop conscious horses (P = 0.379). CONCLUSIONS: Administration of xylazine to anesthetized horses resulted in an increased CPP due to decreased ICP with concurrent increased MAP. Administration of xylazine to standing horses did not result in a change in ICP. However, with the increase in BPdop found in awake horses, it is likely that CPP would also increase in awake horses following xylazine administration.

Evaluation of transpalpebral ultrasonographic measurement of optic nerve sheath diameter for indirect assessment of intracranial pressure in anesthetized and standing healthy adult horses.

OBJECTIVE: To determine whether an association exists between direct intracranial pressure (ICP) measurement and ultrasonographic measurement of optic nerve sheath diameter (ONSD) in anesthetized and standing horses. DESIGN: Cross-sectional study performed on a convenience sample of healthy adult horses. SETTING: University teaching hospital. ANIMALS: Eight adult horses donated to the University. Enrolled horses were free of abnormalities on physical examination, CBC, neurological evaluation, and ophthalmological examination. MEASUREMENTS AND MAIN RESULTS: Horses were anesthetized in lateral recumbency for placement of an ICP transducer. Three head positions (neutral, elevated, and lowered) were used to alter ICP. ICP and ONSD in 2 directions (D1 and D2) were recorded at 5 and 10 minutes after position change to elevated and lowered. ICP and ONSD measurements were repeated in standing sedated horses 24-36 hours after recovery from anesthesia. Linear regressions were performed with ICP as the dependent variable and ONSD as the independent variable by head position and times. Linear regressions were also performed for change from neutral under anesthesia, with ONSD as the independent variable and ICP as the dependent variable, by head position and times. Significance was set at P < 0.05. There was a moderate association between ICP and ONSD in horses with head lowered at 5 and 10 minutes (R2 values = 63%-78%) and weak association in head elevated at 10 minutes (R2 values = 56%-63%). There was a weak association between change from neutral ICP and change from neutral ONSD in the elevated anesthetized position at 10 minutes for summed D1 + D2 (R2  = 33%). CONCLUSIONS: Consistent associations between direct ICP and ONSD in anesthetized or standing horses were not observed. This inconsistency limits the clinically utility of transpalpebral ultrasonographic ONSD measurement for ICP monitoring in horses.

Golden retriever pigmentary uveitis: Challenges of diagnosis and treatment.

Pigmentary uveitis (PU), also known as Golden Retriever Pigmentary Uveitis (GRPU), is a common ocular condition of Golden Retrievers that has severe, vision-threatening ocular complications and can require surgical intervention. In order to ensure consistency in the diagnosis of GRPU between examiners, a specified set of diagnostic criteria must be applied. This is critical to ensure owners, breeders, and veterinary ophthalmologists maintain confidence in the ocular certification process. Therefore, current and former members of the American College of Veterinary Ophthalmologists' Genetics Committee came together to draft this Viewpoint Article on the challenges of diagnosis and treatment of Golden Retriever Pigmentary Uveitis for veterinary ophthalmologists, Golden Retriever owners, and Golden Retriever breeders.

Eye removal following parotid duct transposition surgery: A survey of current practice among veterinary ophthalmologists.

OBJECTIVE: Identify dogs that required removal of an eye that had previously undergone a parotid duct transposition (PDT) and secondly to characterize demographics, surgical technique, and outcomes associated with it. PROCEDURE: An online survey was distributed to American College of Veterinary Ophthalmologists (ACVO) and Veterinary Ophthalmology (VOPH) listservs asking members to report the breed, reason for eye removal, time between surgeries, surgical technique, complications, and additional therapy instituted for dogs requiring removal of an eye subsequent to PDT surgery. RESULTS: Sixteen dogs fit the inclusion criteria. Small breeds (<15 kg) made up 80% of the study population. Time between surgeries was <6 months (1/16), 6 to 12 months (7/16), and ≥1 year (8/16). Reasons for eye removal included: advancing corneal disease (6/16), discomfort (6/16), reaction to saliva (4/16), decreased saliva production (2/16), glaucoma (1/16), orbital neoplasia (1/16), and endophthalmitis (1/16). Surgical techniques included: transection of the parotid duct without ligation (2/16), ligation (9/16), and reversal of the PDT with reimplantation into the mouth (5/16). Complications reported were two dogs who underwent duct ligation experienced prolonged dilation of the duct that resolved with medical therapy (1/2) or without additional therapy (1/2). CONCLUSION: Ligation of or reversal of the PDT with reimplantation into the mouth are appropriate adjunctive surgical techniques when removing an eye that previously underwent PDT surgery. Two dogs with nonfunctional PDT had complication-free eye removal with transection without ligation. Prolonged dilation of the duct is possible after eye removal with duct ligation and may resolve with time or medical management.

Bandage contact lens retention in dogs-A pilot study.

OBJECTIVE: To assess and compare retention, application characteristics, and patient tolerance of nine bandage contact lens types from four manufacturers. ANIMALS STUDIED: Six research Beagles were used in this pilot study. PROCEDURE: Five bandage contact lens types from two veterinary brands and four bandage contact lens types from two human brands were evaluated in six research Beagles. Placement ease, the dogs' contact lens tolerance, and contact lens retention time for up to 14 days were recorded. Statistical analysis with a linear mixed model was performed. RESULTS: Veterinary contact lenses had an average retention time of 0.4 days (range 0-7 days, with an average of 10% and 3% retained ≥1 and ≥7 days, respectively), while human contact lenses had a significantly (P < 0.0001) longer average retention time of 5.2 days (range 0-14 days, with an average of 83% and 37.5% retained ≥1 and ≥7 days, respectively). Specifically, Johnson and Johnson Vision Care Acuvue® Oasys™ with Hydraclear™ Plus lenses were retained significantly longer than all veterinary lenses, and Bausch and Lomb PureVision® 2 lenses were retained significantly longer than Keragenix HydroBlues™ 18 and AnimaLens™ HRT 78 18 mm lenses. CONCLUSION: Although all bandage contact lenses were easy to use and well tolerated by the dogs, the human lenses were retained significantly better and longer than the veterinary lenses. Additionally, human lenses were retained significantly better and longer than veterinary lenses of similar measurements. This suggests factors other than measurement and associated fit may determine contact lens retention time.

Effect of propofol and ketamine-diazepam on intraocular pressure in healthy premedicated dogs.

OBJECTIVE: To compare the effect of propofol and ketamine/diazepam for induction following premedication on intraocular pressure (IOP) in healthy dogs. STUDY DESIGN: Prospective, quasi-experimental, unmasked, longitudinal. ANIMALS: A total of 61 client-owned dogs. METHODS: Dogs were anesthetized twice with a 4 week washout period. Premedication with dexmedetomidine (5 µg kg-1) and hydromorphone (0.1 mg kg-1) intramuscularly was followed by either propofol (4 mg kg-1) or ketamine (5 mg kg-1) and diazepam (0.25 mg kg-1) intravenously for induction and inhaled isoflurane for maintenance. IOP was measured by applanation tonometry using TonoPen-XL before premedication and after 5, 10, 20 and 30 minutes. IOP was measured again immediately after induction and after 3, 5, 10, 15, 20, 30 and 40 minutes. Data were analyzed using one- or two-way repeated measures ANOVA. RESULTS: No difference was found between right and left IOP (p = 0.45), and data from both the eyes of each dog were averaged and considered as one set of data. Following premedication, IOP was significantly lower at all time points than at baseline when animals were grouped together, mean difference -1.6 ± 0.2 mmHg (p < 0.05). IOP increased immediately (12.2 ± 2.4 mmHg before versus 17.1 ± 3.8 mmHg after) and at 3, 5 (p < 0.001), 10 and 40 minutes (p = 0.009 and 0.045, respectively) after propofol administration. For ketamine/diazepam, IOP was increased immediately post-induction (13.0 ± 2.7 mmHg before versus 14.7 ± 2.8 mmHg after) and at 3, 5 (p < 0.001), 30 and 40 minutes (p = 0.010 and 0.037, respectively). CONCLUSIONS AND CLINICAL RELEVANCE: Sedation with hydromorphone and dexmedetomidine significantly decreased IOP in normal dogs and may be an appropriate choice for dogs that cannot tolerate acute increases in IOP. However, IOP increased significantly after both induction protocols, abolishing the effect of premedication.

Analysis of Small Animal Rotating Internship Applicants' Personal Statements.

The primary purpose of this study was to identify themes that are consistent across veterinary internship applicants' personal statements and that are correlated with the statements' perceived overall quality. A secondary purpose was to investigate the reliability in personal statement quality scoring among six experienced internship candidate evaluators. One hundred applications to the University of Georgia Small Animal Rotating Internship program were evaluated. Each evaluator wrote a description of what he or she values in personal statements and his or her beliefs about content and presentation in high- and low-quality statements. After statement de-identification, each evaluator reviewed 15 randomly selected personal statements from internship applicants and assigned each a score ranging from 1 to 4 according to the following criteria: 1 = would not rank for an internship; 2 = would rank in the bottom third; 3 = would rank in the middle third; and 4 = would rank in the top third. A subset of these scored personal statements was chosen for qualitative analysis. A qualitative document analysis using grounded theory was performed for both the evaluators' descriptions of preferences in personal statements and the subset of personal statements. Agreement among evaluators' assigned scores was slight (Fleiss's κ = 0.11). Analysis of the evaluator statements and the scored candidate statements indicated that important factors in a personal statement include the applicant's ability to articulate experiences, to convey maturity, to demonstrate understanding of what an internship entails, and to describe reasons for pursuing an internship.

Orbital invasive squamous cell carcinoma with adnexal involvement clinically mimicking feline restrictive orbital myofibroblastic sarcoma: 19 cases (1990-2016).

OBJECTIVE: To describe the clinical presentations of patients diagnosed with ocular adnexal or orbital squamous cell carcinoma (SCC), which possess features similar to feline restrictive orbital myofibroblastic sarcoma (FROMS). PROCEDURES: A retrospective review of adnexal and/or orbital SCC was performed. Cases were collected from the University of Georgia College of Veterinary Medicine and the Comparative Ocular Pathology Laboratory of Wisconsin (COPLOW) (1990-2016). Data included signalment, ophthalmic clinical signs, nonophthalmic history and clinical signs, clinician suspicion of FROMS, advanced imaging results, and subsequent histopathologic diagnosis. FROMS cases from the COPLOW over the same time span were reviewed and compared statistically to the SCC cases with a significance threshold of 0.05. RESULTS: Nineteen cases (20 eyes) were identified with adnexal SCC with features similar to FROMS, including keratitis and eyelid/third eyelid restriction and/or thickening. There were no statistically significant differences between clinical findings in the SCC cases and the identified and compared FROMS cases (57 cases; 67 eyes), except for exophthalmos and/or resistance to retropulsion, which was less common in SCC cases (20%) than in FROMS cases (47.8%) (P = 0.027); and clinical or imaged presence of an overt eyelid or orbital mass, which was more common in the SCC cases (30%) than in the FROMS cases (4.5%) (P = 0.0010). CONCLUSIONS: SCC with adnexal involvement has many features similar to FROMS. In addition to FROMS, SCC should be considered a differential diagnosis in cats with restrictive adnexal or orbital signs and corneal changes.

Effect of auriculopalpebral nerve block on Schirmer tear test I values in normal horses.

OBJECTIVE: To compare Schirmer tear test I (STTI) values collected in normal horses with and without an auriculopalpebral nerve block. PROCEDURE: Schirmer tear test I values were measured in 20 clinically normal horses (38 eyes) with a median age of 12 years. The order of eyes tested was randomized. Within 24-48 h, at the same time of day, tear measurements were collected again after administration of an auriculopalpebral nerve block. Each block was performed a minimum of 5 min prior to each STT I. A repeated-measures model was used to analyze differences between STT I values in eyes with and without nerve blocks incorporating within horse correlation between eyes. The mixed-model included fixed factors of treatment and eye and a random intercept for each horse. An unstructured covariance structure was used. RESULTS: On average, STT I values measured in eyes after auriculopalpebral nerve blocks were 0.55 mm/min greater than those without nerve blocks. This difference was not statistically significant (P = 0.5268). CONCLUSIONS: There was no effect of auriculopalpebral nerve block on STT I values in normal horses.

Eye Removal Surgeries in Exotic Pets.

This article covers considerations and techniques of eye removal surgeries in exotic pets. After issues including surgical indications, anesthesia, patient preparation, and instrumentation are explored, surgical techniques are described. Enucleation/exenteration and modified evisceration are discussed, with species-specific nuances of small mammals, birds, reptiles, snakes, amphibians, and fish highlighted.

Bilateral phacoemulsification and intraocular lens implantation in a great horned owl.

CASE DESCRIPTION: A great horned owl of estimated age < 1 year that was captured by wildlife rehabilitators was evaluated because of suspected cataracts. CLINICAL FINDINGS: Nuclear and incomplete cortical cataracts were evident in both eyes. Ocular ultrasonography revealed no evidence of retinal detachment, and electroretinography revealed normal retinal function. TREATMENT AND OUTCOME: For visual rehabilitation, cataract surgery was planned and intraocular lens design was determined on the basis of values obtained from the schematic eye, which is a mathematical model representing a normal eye for a species. Cataract surgery and intraocular lens placement were performed in both eyes. After surgery, refraction was within -0.75 diopters in the right eye and -0.25 diopters in the left eye. Visual rehabilitation was evident on the basis of improved tracking and feeding behavior, and the owl was eventually released into the wild. CLINICAL RELEVANCE: In raptors with substantial visual compromise, euthanasia or placement in a teaching facility is a typical outcome because release of such a bird is unacceptable. Successful intraocular lens implantation for visual rehabilitation and successful release into the wild are achievable.

Effects of the application of neck pressure by a collar or harness on intraocular pressure in dogs.

The effect on intraocular pressure (IOP) from dogs pulling against a collar or a harness was evaluated in 51 eyes of 26 dogs. The force each dog generated while pulling against a collar or a harness was measured. Intraocular pressure measurements were obtained during application of corresponding pressures via collars or harnesses. Intraocular pressure increased significantly from baseline when pressure was applied via a collar but not via a harness. Based on the results of the study, dogs with weak or thin corneas, glaucoma, or conditions for which an increase in IOP could be harmful should wear a harness instead of a collar, especially during exercise or activity.