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Mast cell infiltration occurs in malignant, inflammatory (eg, allergic, infectious), and idiopathic disease processes in humans and animals. Here, we describe the clinical and histological features of a unique proliferative conjunctivitis occurring in 15 cats. Ocular specimens were examined histologically, and polymerase chain reaction (PCR) for feline herpesvirus 1 (FHV-1) was performed on ocular tissues obtained from 10 cats. Cats had a median age of 8 years (range: 7 months-17.5 years). The known median duration of ocular lesions prior to biopsy was 4 months (range: 1 week-3 years). Ocular disease was unilateral in 12 cats, and 9 cats had coexisting corneal disease. Clinically and histologically, proliferative or nodular conjunctival lesions were noted in 13 cats. The nictitating membrane was affected in 10 cats. Histologically, lesions were characterized by mixed inflammatory infiltrates with an abundance of Giemsa-positive and toluidine blue-positive intraepithelial and subepithelial mast cells, marked edema, and papillary epithelial hyperplasia. Feline herpesvirus 1 was demonstrated by PCR in 1 of 10 cats tested. Follow-up information was available for 14 cats: 8 had no recurrence during a median follow-up period of 17.5 months (range: 4.5-30 months), 2 underwent orbital exenteration, 3 had recurrence that was medically managed, and 1 cat had diffuse conjunctivitis at the time of biopsy and recurrence was deemed irrelevant. Various ocular medications were administered before and after surgical biopsy. This condition was designated as feline epitheliotropic mastocytic conjunctivitis, with intraepithelial mast cells being an essential feature and papillary epithelial proliferation being characteristic but not diagnostic alone. The condition appears to be uncommon and benign. Although the cause is unknown, an allergic component is possible.

Although famciclovir is efficacious in feline herpesvirus type 1 (FHV-1)-infected cats, effects of a single dose early in disease course have not been reported. In this two part, randomized, masked, placebo controlled study, cats received a single dose of 125 mg famciclovir (n = 43) or placebo (n = 43; pilot study), or 500 mg famciclovir (n = 41) or placebo (n = 40; clinical trial) on entering a shelter. FHV-1 PCR testing was performed, bodyweight and food intake were recorded, and signs of respiratory disease were scored prior to and 7 days following treatment. FHV-1 DNA was detected in 40% of cats in both parts at study entry. In the pilot study, ocular and nasal discharge scores increased from days 1 to 7 in famciclovir and placebo treated cats. Sneezing scores increased and bodyweight decreased in famciclovir-treated cats. The proportion of cats in which FHV-1 DNA was detected increased over time in all cats in the pilot study. In the clinical trial, food intake and median clinical disease scores for nasal discharge and sneezing increased from days 1 to 7 in both groups and demeanor scores worsened in famciclovir-treated cats. The proportion of cats shedding FHV-1 DNA was greater on day 7 than on day 1 in cats receiving 500 mg famciclovir. A single dose of famciclovir (125 or 500 mg) administered at shelter intake was not efficacious in a feline population in which 40% were already shedding FHV-1.

Objectives: The aim of this study was to prospectively evaluate in a randomized, triple-masked, placebo-controlled trial, outcomes for kittens with ocular manifestations of infectious upper respiratory disease (IURD) treated with an ophthalmic and oral antibiotic only vs those also treated with famciclovir., Methods: Kittens were stratified into three age (1 to <4, 4 to <8 or 8-12 weeks) and two disease severity ('mild' [total disease score 1-11] or 'severe' [total disease score 12-23]) groups and randomized to receive approximately 5 mg/kg doxycycline either with placebo (group D) or with approximately 90 mg/kg famciclovir (group DF) PO q12h. Caregivers scored clinical signs once daily for 21 days. Ophthalmic examinations and scoring by veterinarians were completed on days 1 and 21. Ophthalmic and clinical resolution were defined as scores of zero for all ocular signs and all ocular and respiratory signs, respectively. Ophthalmic and clinical recovery were defined by absence of active inflammation., Results: For kittens with mild disease, those in group D were slower than those in group DF to achieve clinical recovery ( P  = 0.049) and clinical resolution ( P  = 0.030), but not ophthalmic recovery ( P  = 0.064) or ophthalmic resolution ( P  = 0.089). Kittens with mild disease and receiving famciclovir achieved predicted 75% clinical resolution 4-5 days earlier than kittens with mild disease and receiving doxycycline alone, and kittens with severe disease (regardless of treatment group). Significantly fewer kittens in group DF developed corneal disease than in group D ( P  = 0.016). All five kittens whose clinical signs worsened sufficiently to be removed from the study were in group D., Conclusions and Relevance: The addition of famciclovir to standard antibiotic treatment may reduce corneal disease, length of stay and time to adoption for shelters and rescue groups, thereby increasing capacity for care. Early administration of famciclovir in kittens exhibiting mild ocular manifestations of IURD may be preferable to delaying this treatment until the disease progresses to a severe stage., Competing Interests: Conflict of interestThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Objective: To determine the impact of chronic dental disease on the nasolacrimal duct of chinchillas using contrast CT dacryocystorhinography., Animals Studied: Two 12-year-old female chinchillas with uni- or bilateral ocular discharge and a history of chronic, moderate (Chinchilla 1, one-year) or severe (Chinchilla 2, three-years) dental disease., Procedures: Contrast CT dacryocystorhinography was performed to identify abnormalities in the nasolacrimal duct and dentition, and to correlate those changes., Results: Chinchilla 1 had a focal soft tissue attenuating expansion of the maxillary bone rostral to the first left premolar interpreted as possible abscessation causing deviation of the nasolacrimal duct over its dorsomedial margin. The right nasolacrimal duct appeared normal. Chinchilla 2 had periapical abscessation of a retained subgingival left maxillary incisor fragment which extended into the nasal cavity causing focal narrowing and distal dilation of the left nasolacrimal duct. Complete contrast infusion of the right nasolacrimal duct could not be completed on Chinchilla 2. A focal area of superficial corneal fibrosis ipsilateral to the obstructed nasolacrimal duct was also identified in Chinchilla 2. Treatment consisted of occlusal adjustments to correct the coronal elongation, systemic antibiotics (metronidazole and either marbofloxacin or azithromycin), and topical tear replacement therapy and diclofenac as needed. Ocular discharge decreased in both chinchillas but did not resolve long-term in either animal., Conclusions: Chronic dental disease including periapical abscessation in chinchillas can obstruct the nasolacrimal duct, leading to impaired tear drainage. Management of dental disease is crucial to maintain patency of the nasolacrimal duct., (© 2024 The Author(s). Veterinary Ophthalmology published by Wiley Periodicals LLC on behalf of American College of Veterinary Ophthalmologists.)

Background: Non-human animals are natural hosts for the virus causing COVID-19 (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) and a diversity of species appear susceptible to infection. Cats are of particular concern because of their close affiliation with humans and susceptibility to infection. Cats also harbour feline enteric coronavirus (FECV). Our objectives were to document the prevalence of SARS-CoV-2 and FECV in feline populations with high turnover and movement among households in the Central Valley of California, USA., Methods: A cross-sectional study of 128 shelter and foster cats and kittens in the Central Valley of California was performed from July to December 2020. PCR was performed on rectal and oropharyngeal samples to detect SARS-CoV-2 RNA and on rectal samples to detect FECV RNA., Results: Among 163 rectal and oropharyngeal fluid samples gathered from sheltered and fostered cats and kittens in central California, SARS-CoV-2 nucleic acids were not detected from any cat or kitten. In contrast, FECV nucleic acids were detected in 18% of shelter-housed cats; 83% of these positive samples were collected from cats housed in adjacent cages., Conclusions: These data may be helpful when considering the allocation of resources to minimise the harm of FECV and SARS-CoV-2 in household pets and shelter environments., Competing Interests: The authors declare they have no conflicts of interest., (© 2023 The Authors. Veterinary Record Open published by John Wiley & Sons Ltd on behalf of British Veterinary Association.)

Background: Polyautoimmunity is the expression of more than one autoimmune disease in a single patient. This report documents polyautoimmunity in a mixed breed dog with concurrent uveitis, cutaneous depigmentation, and inflammatory myopathy., Case Presentation: A 1-year-old male neutered mixed breed dog was presented for progressive generalized leukotrichia and leukoderma, bilateral panuveitis, and masticatory muscle atrophy. The latter progressed to myositis of lingual, pharyngeal, and masticatory muscles confirmed by biopsy. Temporalis muscle was completely replaced by adipose and fibrous tissue, and necrotic myofibers with extensive infiltration of mononuclear cells indicated active myositis of lingual muscle. Skin biopsies showed severe melanin clumping in epidermis, hair follicles, and hair shafts, and perifollicular pigmentary incontinence. Uveitis, depigmentation, and myositis affecting the masticatory, pharyngeal, and tongue muscles were diagnosed based on clinical, histological, and laboratory findings., Conclusions: To the authors' knowledge, this is the first report of concurrent uveitis, progressive cutaneous depigmentation, and inflammatory myopathy in a dog., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Objective: To describe normative ocular surface and aqueous tear testing data for cats of various cephalic conformation., Animals Studied: Fifty-three healthy adult cats (11 British Shorthair, 11 Burmese, 10 Devon Rex, 10 Scottish Fold, and 11 Sphynx)., Procedures: Blink rate, corneal tactile sensation (CTS), and Schirmer tear test with or without topical anesthesia (STT-1, STT-2) and with nasolacrimal stimulation (NL-STT1, NL-STT2) were assessed. Palpebral fissure length (PFL) and skull morphology were measured, and cephalic index (CI) and craniofacial ratio (CFR) calculated., Results: Mean ± SD test results were as follows: blink rate (5.0 ± 2.3 blinks/min), CTS (3.2 ± 0.7 cm), STT-1 (11.2 ± 4.3 mm/min), STT-2 (6.7 ± 3.6 mm/min), NL-STT1 (13.4 ± 5.7 mm/min), NL-STT2 (13.5 ± 5.2 mm/min), and PFL (2.0 ± 0.2 cm). Corneal sensitivity did not differ significantly among breeds (p = .152) but was negatively correlated with body weight (r = -.32, p = .019). STT-1 significantly differed among breeds (p < .001) and was lowest in Sphynx cats (8.7 ± 4.3 mm/min). A positive correlation was detected between STT-1 values at 30 and 60 s (r = .98; p < .001). The nasolacrimal reflex significantly increased STT in anesthetized and unanesthetized eyes (approximately +100% and +20%, respectively; p ≤ .002). STT-1 tended to be higher in intact versus neutered cats (p = .062). Age did not impact any test result (p ≥ .085)., Conclusions: Normative data described here serve as a baseline for future studies assessing ocular surface disease in multiple feline breeds. Unlike dogs, brachycephalic cats did not have lower CTS or STT-1 than non-brachycephalic cats., (© 2022 The Authors. Veterinary Ophthalmology published by Wiley Periodicals LLC on behalf of American College of Veterinary Ophthalmologists.)

Objectives: The aim of this study was to retrospectively evaluate the signalment, treatment, surgical technique and outcomes for feline symblepharon., Methods: A retrospective medical record review and standardized grading of clinical descriptions and photographs was undertaken., Results: Forty kittens (54 eyes) aged 3-46 weeks had symblepharon of five types in various combinations: eyelid deformation (24 kittens; 32 eyes); ankyloblepharon (four kittens; four eyes); conjunctiva-to-conjunctiva (11 kittens; 12 eyes); third eyelid-to-conjunctiva (24 kittens; 29 eyes); and corneoconjunctival adhesions (14 kittens; 16 eyes). At initial presentation, 23 (43%) eyes were affected by one type of symblepharon, 25 (46%) eyes by two types and six (11%) eyes by three types; 11 (20%) corneas were ulcerated. Twenty-four (44%) eyes of 18 (45%) kittens were managed medically. Surgery was performed under general anesthesia/sedation (30 occasions) or topical anesthesia (21 occasions) on 30 (56%) eyes of 22 kittens; 12 eyes (40%) underwent multiple surgeries. Four techniques were commonly employed: separation of conjunctival-to-conjunctival adhesions ± eyelid margins (14 eyes); resection of third eyelid adhesions ± temporary tacking of the third eyelid (modified Arlt's pterygium technique; 18 eyes); en bloc resection of the third eyelid (two eyes); and separation of corneoconjunctival adhesions (14 eyes). Median duration of follow-up was 55 days (range 1-1051). Median symblepharon grade in kittens treated surgically improved for all types except corneoconjunctival symblepharon. Median symblepharon grade in kittens receiving medical management remained the same or improved. Corneoconjunctival symblepharon opacity decreased for eyes treated surgically but increased for eyes treated medically. Three eyes were enucleated due to complications of corneoconjunctival symblepharon. At final presentation, symblepharon persisted in 46 (85%) eyes; however, menace response was evident in 13/16 eyes and dazzle reflex in 23/23 eyes., Conclusions and Relevance: Symblepharon is a heterogeneous group of conditions with diverse anatomic involvement, clinical appearance and impact, optimal treatment and prognosis for vision.

Feline herpesvirus type 1 (FHV-1) is endemic in captive cheetahs and sporadically causes devastating disease. Modified live vaccines (MLV), intended for use in domestic cats, are used in some captive cheetah populations and have been anecdotally linked to disease in certain subpopulations. Ten FHV-1 isolates from ten captive cheetahs and one isolate from an MLV used to inoculate four of the host animals were analyzed. Viral DNA was extracted for full-genome sequencing by Illumina MiSeq with viral genomes then used for phylogenomic and recombinational analyses. The FHV-1 shed by vaccinated cheetahs were almost identical to the MLV, with few variants among viral genomes. Eight cheetah FHV-1 isolates and the MLV were grouped in a clade along with FHV-1 isolates from domestic cats in the USA. The remaining two cheetah FHV-1 isolates (unknown host vaccine status) were not associated with a clade. The likely ancestral origin of these two isolates involves recombination events between Australian domestic cat and cheetah FHV-1 isolates. Collectively, these data suggest that the MLV is capable of causing clinical disease and viral shedding in some cheetahs and represents evidence of interspecies transmission of virus between domestic and wild cats.

Objective: To compare intraocular pressures (IOPs) estimated by rebound and applanation tonometry for dogs with lens instability., Animals: 66 dogs., Procedures: Medical records of dogs examined between September 2012 and July 2018 were reviewed for diagnoses of anterior (ALL) or posterior (PLL) lens luxation or lens subluxation., Results: Estimates of IOP obtained with rebound and applanation tonometry significantly differed from each other for all types of lens instability considered collectively (mean ± SE difference between tonometric readings, 8.1 ± 1.3 mm Hg) and specific types of lens instability considered individually (mean ± SE difference between tonometric readings: ALL, 12.8 ± 2.5 mm Hg; PLL, 5.9 ± 1.7 mm Hg; subluxation, 2.8 ± 0.8 mm Hg). Median (range) differences between rebound and applanation tonometer readings for dogs with ALL was 5 mm Hg (-9 to 76 mm Hg), with PLL was 3 mm Hg (-1 to 19 mm Hg), and with lens subluxation was 3 mm Hg (-9 to 18 mm Hg). In eyes with ALL, rebound tonometer readings exceeded applanation tonometer readings on 44 of 60 (73%) occasions., Conclusions and Clinical Relevance: Rebound tonometry yielded higher estimates of IOP than did applanation tonometry in eyes with ALL and with all types of lens luxation considered collectively. Estimates of IOP in eyes with lens instability should ideally be obtained with both rebound and applanation tonometers. Veterinarians with only one type of tonometer should interpret results for dogs with lens instability concurrent with physical examination findings.

Objective: To assess correlations between clinical and cytological features of feline eosinophilic keratoconjunctivitis at the time of cytological diagnosis., Animals Studied: Fifteen client-owned, domestic breed cats (18 eyes) examined between 2007 and 2019., Procedures: An electronic search and medical record review of cats diagnosed with feline eosinophilic keratitis or keratoconjunctivitis (FEK) based on clinical examination findings and eosinophils detected on corneal cytology were conducted. Clinical severity was graded using a modified version of a previously validated semiquantitative preclinical ocular toxicology scoring (SPOTS) system. Clinical grades were assigned following review of clinical images and medical record descriptions, and cytological grades were assigned following review of archived corneal cytology slides. Correlations were analyzed for significance using Spearman's rank correlation coefficient., Results: Higher total corneal scores correlated with higher total conjunctival scores, but not with total fluorescein scores. Small lymphocyte scores correlated negatively with scores for collagen degeneration or mineralization. Globule leukocytes, a unique cell type not previously described in ocular cytology, were identified in 4 of 18 cytological samples. Higher globule leukocyte scores were correlated with higher scores for mast cells or plasma cells. Specimens with lower eosinophil scores had higher globule leukocyte scores., Conclusions: Large variability was detected in the cytological characteristics and clinical features of FEK-affected cats. This is the first report of globule leukocytes being identified in ocular cytology from any species. The role of globule leukocytes in the etiopathogenesis and progression of FEK remains unknown and warrants further investigation., (© 2021 The Authors. Veterinary Ophthalmology published by Wiley Periodicals LLC on behalf of American College of Veterinary Ophthalmologists.)

Objectives: The aim of this retrospective case-control study was to report the efficacy of subcutaneous triamcinolone as part of a regimen for feline eosinophilic keratoconjunctivitis (FEK)., Methods: Records and clinical photographs were reviewed and lesions semiquantitatively graded for cats with cytologically confirmed FEK. Clinical data were compared between a study population of nine cats (11 eyes) treated with, and a reference population of seven cats (eight eyes) treated without, a median of 0.11 mg/kg (range 0.10-0.20 mg/kg) of triamcinolone acetonide subcutaneously., Results: Breed, sex, age and prevalence of corneal ulceration at presentation; corneal disease severity before and at the initiation of immunomodulation; and duration of antiviral treatment before immunomodulation did not differ significantly between populations ( P ⩾0.059). Corneal plaques resolved in five cats each from the study and reference populations ( P  = 0.366). Median (range) time from immunomodulation to corneal plaque resolution did not significantly differ ( P  = 0.246) between the study (median 14 days; range 8-38 days) and reference (median 28 days, range 14-46 days) populations. No adverse reactions were attributed to triamcinolone administration, and all corneal ulcers in the study population re-epithelialized within 14 days (range 8-38 days) following triamcinolone injection. Time to corneal ulcer re-epithelialization following triamcinolone injection varied minimally in those receiving antivirals prior to (8 or 30 days until re-epithelialization), simultaneously with (38 days) or after (14 or 24 days) triamcinolone., Conclusions and Relevance: In otherwise healthy cats with FEK, subcutaneous administration of triamcinolone appears to be well tolerated and as efficacious as conventional topical immunomodulatory therapies. It may be especially useful in ulcerated eyes where topical immunomodulation is contraindicated.

Purpose: To retrospectively evaluate the clinical data, diagnostic tests, treatments, and outcomes for dogs with corneal endothelial dystrophy (CED) and determine risk factors for CED when compared with a canine reference population., Methods: Medical records of 99 dogs (1991-2014) diagnosed with CED at the University of California Davis Veterinary Medical Teaching Hospital were reviewed and compared with 458,680 dogs comprising the general hospital population during the study period. Retrieved data included signalment, examination findings, diagnoses, treatments, and outcomes associated with CED. The exact Pearson χ2 test or exact Kruskal-Wallis test was used to compare parameters between the groups. Progression of corneal edema was assessed using 3 independent Kaplan-Meier curves, identifying clinically significant changes in corneal opacity., Results: Boston terriers, German wirehaired pointers, and Dachshunds were overrepresented in the CED-affected group, whereas Labradors were underrepresented. Dogs older than 11 years were overrepresented in the CED-affected group, whereas intact dogs were underrepresented. Surgical intervention was performed (n = 11) based on the severity of disease and secondary complications from CED. Median time to progression of corneal edema was 1) 368 days when an at-risk eye initially without edema developed edema at a subsequent visit, 2) 701 days when there was progression from mild to marked corneal edema, and 3) 340 days when there was progression from focal to diffuse corneal edema., Conclusions: Many CED-affected dogs progress over months to years without surgical intervention, making dogs with CED a useful model for studying genetic predispositions and development of novel therapeutics for Fuchs endothelial corneal dystrophy., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Objectives: The aim of this study was to evaluate changes in the conjunctival microbiota of shelter-housed cats with time, upper respiratory disease (URD) and famciclovir administration., Methods: Cats were assigned to treatment groups on shelter entry. Healthy cats or cats with URD received ~30 mg/kg or ~90 mg/kg of famciclovir or placebo PO q12h for 7 days, or were untreated. Swabs were collected from ventral conjunctival fornices prior to (day 1) and immediately after (day 8) the treatment period. Microbiota analysis was conducted on 124 randomly selected swabs from healthy (56 swabs) or URD-affected (68 swabs) cats. Following DNA extraction and amplification of the V4 region of the 16S rRNA gene, sequences were assembled into operational taxonomic units (OTUs). Over-represented OTUs (as determined by linear discriminate analysis effect size), alpha and beta diversity, and median relative abundance of known feline ocular surface pathogens were assessed for the entire population and in 10 clinically relevant subpopulations of cats., Results: Bacteria from 33 phyla and 70 genera were identified. Considering all cats, median relative abundance of Mycoplasma increased from day 1 to day 8, while Proteobacteria decreased. Community membership and structure (beta diversity) differed between days 1 and 8 for all famciclovir-treated cats (regardless of health status or dose) and healthy or URD-affected cats (regardless of famciclovir dose). Differences in taxonomic diversity within a sample (alpha diversity) between day 1 and day 8 were not detected in any subpopulations., Conclusions and Relevance: Within 1 week of shelter entry, there were significant changes in community structure and membership of the feline conjunctival microbiota, with a shift towards over-representation of feline ocular surface pathogens. Although famciclovir may impact beta diversity of the feline conjunctival microbiota, absence of change in alpha diversity suggests minimal shift in individual cats.

Metaherpetic disease is recognized in humans affected by herpes simplex virus-1 but is not reported in cats affected by feline herpesvirus-1 (FHV-1) despite the high prevalence of herpetic disease in this species and strong similarities in viral biology between alphaherpesviruses of humans and cats. This preliminary work evaluated cats naïve to FHV-1 ( n = 9 cats, 18 eyes; control population) and cats naturally exposed to FHV-1 ( n = 4 cats, 7 eyes), as confirmed by serologic testing and review of medical records. Antemortem assessment included clinical scoring, blink rate, corneal aesthesiometry, tear film breakup time (TFBUT), and Schirmer tear test-1 (STT-1) with or without the nasolacrimal reflex. Post-mortem assessment involved confocal microscopy of the corneas and evaluation of corneal nerves with ImageJ. Groups were compared with Student's t -tests and results are presented as mean ± standard deviation. Compared to control, herpetic cats had significantly higher ( P ≤ 0.010) clinical scores (0.2 ± 0.4 vs . 4.6 ± 2.8) and response to nasolacrimal stimulation (7.8 ± 10.8% vs . 104.8 ± 151.1%), significantly lower ( P < 0.001) corneal sensitivity (2.9 ± 0.6 cm vs . 1.4 ± 0.9 cm), STT-1 (20.8 ± 2.6 mm/min vs . 10.6 ± 6.0 mm/min), TFBUT (12.1 ± 2.0 s vs . 7.1 ± 2.9 s), and non-significantly lower blink rate (3.0 ± 1.5 blinks/min vs . 2.7 ± 0.5 blinks/min; P = 0.751). All parameters evaluated for corneal nerves (e.g., nerve fiber length, branching, occupancy) were notably but not significantly lower in herpetic vs . control cats ( P ≥ 0.268). In sum, cats exposed to FHV-1 had signs suggestive of corneal hypoesthesia and quantitative/qualitative tear film deficiencies when compared to cats naïve to the virus. It is possible these are signs of metaherpetic disease as reported in other species., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Sebbag, Thomasy, Leland, Mukai, Kim and Maggs.)

Objectives: The aim of this study was to assess the effects of famciclovir administration in cats with spontaneously acquired acute upper respiratory tract disease., Methods: Twenty-four kittens with clinical signs of acute upper respiratory tract disease were randomly allocated to receive doxycycline (5 mg/kg PO q12h) alone (group D; n = 12) or with famciclovir (90 mg/kg PO q12h; group DF; n = 12) for up to 3 weeks. Clinical disease severity was scored at study entry and daily thereafter. Oculo-oropharyngeal swabs collected at study entry and exit were assessed using quantitative PCR for nucleic acids of feline herpesvirus type 1 (FHV-1), feline calicivirus (FCV), Chlamydia felis, Bordetella bronchiseptica and Mycoplasma felis ., Results: The median (range) age of cats was 1.5 (1-6) months in group D vs 1.6 (1-5) months in group DF ( P = 0.54). Pathogens detected in oculo-oropharyngeal swabs at study entry included FCV (n = 13/24; 54%), M felis (n = 8/24; 33%), FHV-1 (n = 7/24; 29 % ), C felis (n = 7/24; 29%) and B bronchiseptica (n = 3/24; 12%). Median (range) duration of clinical signs was 11.5 (3-21) days in group DF and 11 (3-21) days in group D ( P = 0.75). Median (range) total disease score at the end of the study did not differ between groups (group D 1 [1-1] vs group DF 1 [1-3]; P = 0.08)., Conclusions and Relevance: This study revealed no significant difference in response to therapy between cats treated with doxycycline alone or with famciclovir; cats improved rapidly in both groups. However, identification of FHV-1 DNA was relatively uncommon in this study and clinical trials focused on FHV-1-infected cats are warranted to better evaluate famciclovir efficacy.

Objective: To compare complication rates and visual outcomes following phacoemulsification in Pugs versus dogs of other breeds., Animals Studied: Thirty-two pure-bred Pugs (55 eyes) and 32 dogs of other breeds (56 eyes) undergoing phacoemulsification., Procedures: Multi-institutional retrospective medical record review of perioperative factors, postoperative complications, and visual outcomes. The reference population of dogs of varying breeds included surgical cases following each Pug case at the same institutions. Perioperative risk factors and postoperative complication rates were compared between the two populations., Results: Pigmentary keratitis and diabetes mellitus were the most common preoperative comorbidities, found in 75% (P < .001) and 72% (P = .12) of Pugs, respectively. No perioperative factors were significantly associated with postoperative complications in Pugs. Postoperative complication rates were similar between groups; however, the most common complication in Pugs was corneal ulceration (15% of operated eyes), whereas glaucoma was most common in the reference population (13% of operated eyes). Three months postoperatively, vision was preserved in 91% of eyes of Pugs (50/55) and 95% of the reference population (53/56). One year postoperatively, 80% (32/40) of Pug eyes and 82% (28/34) of eyes in the reference population remained sighted., Conclusions: Comorbidities and complications of cataract surgery in Pugs of this study demonstrate a predisposition for corneal disease. This highlights the importance of preoperative evaluation of factors associated with PK and corneal clarity, and postoperative monitoring for corneal ulceration in this breed., (© 2020 American College of Veterinary Ophthalmologists.)

Objective: Sudden acquired retinal degeneration syndrome (SARDS) is one of the leading causes of acute blindness in dogs, with an unknown etiology and no effective treatment. Certain breeds such as Dachshunds are overrepresented among SARDS patients, and therefore, the syndrome is suspected to have a genetic component. The objective of this study was to determine if a genetic locus associated with SARDS in Dachshunds could be identified using a genome-wide association study (GWAS)., Procedures: Genome-wide association mapping was performed in 15 SARDS-affected and 16 unaffected Dachshunds. Genotyping of three classical DLA class II genes (DLA-DRB1, DLA-DQA1, and DLA-DQB1) was performed in 34 SARDS-affected and 66 unaffected Dachshunds to evaluate for an association in this region., Results: Although no single nucleotide polymorphisms (SNPs) were of genome-wide statistical significance (P Bonferroni  < 0.05), 5 of the top 9 SNPs were in the major histocompatibility complex (MHC). Using DLA typing, the allele DLA-DRB1*09401 was identified as a risk factor for the development of SARDS (P = 0.0032, OR = 4.0). The alleles DLA-DQB1*00101 (P = 0.0050, OR = 0.31), DLA-DQA1*00901 (P = 0.0087, OR = 0.33), and a previously identified DLA-DRB1allele described as "DRB1-T" (P = 0.0284, OR = 0.37) were identified as protective factors., Conclusions: Although far from definitive, association of SARDS with alleles of immunologic importance further supports the hypothesis that autoimmunity may play a role in the pathogenesis of SARDS., (© 2019 The Authors. Veterinary Ophthalmology published by Wiley Periodicals, Inc. on behalf of American College of Veterinary Ophthalmologists.)

Objectives: The aim of this study was to describe the clinical findings, diagnostic test results and response to therapy of cats with Schirmer tear test 1 (STT-1) values below the reference interval., Methods: The medical records of three institutions were searched for cats with ocular surface disease and STT-1 values <9 mm/min, confirmed at two or more separate visits., Results: Ten cats (17 eyes) were included. The mean ± SD (range) age and STT-1 values in affected eye(s) were 6.1 ± 5.7 (0.2-16) years and 2.4 ± 3.1 (0-8) mm/min, respectively. Concurrent ocular surface disease was bilateral in 5/10 cats. Clinical signs included conjunctivitis (14/17 eyes), corneal ulceration (6/17 eyes), non-ulcerative keratitis (4/17 eyes), symblepharon (4/17 eyes), eosinophilic keratitis (3/17 eyes), corneal sequestrum (3/17 eyes), corneal fibrosis (2/17 eyes) and meibomitis (2/17 eyes). Management included: topically applied lacrimomimetics, antiviral drugs, corticosteroids or immunomodulatory drugs; orally administered famciclovir; or surgical procedures, in various combinations. Response to therapy (defined as an increase in STT-1 value of ⩾5 mm/min) was transient (seen at a single reassessment) in 65% of eyes and sustained (seen at ⩾2 consecutive reassessments) in 18% of eyes., Conclusions and Relevance: Clinical features seen in cats with low STT-1 values are described, although the association between aqueous deficiency and the reported ocular changes is unknown at this time. We encourage clinicians to assess the tear film in cats with ocular surface disease, and initiate therapy with lacrimomimetics if STT-1 values are repeatedly below normal. Such information will further define aqueous tear deficiency in cats, providing a better understanding of disease prevalence, pathogenesis and treatment.

Objective: To investigate the effect of topically applied proparacaine on bacterial and fungal culture results and to compare cytologic and culture results in patients with ulcerative keratitis., Procedure: Corneal samples were collected from 33 dogs, 19 horses, and 12 cats with spontaneously arising ulcerative keratitis. Samples for bacterial (dogs, cats, horses) and fungal (horses) cultures were collected prior to and following application of 0.5% proparacaine or saline. All patients then received a topical anesthetic, and samples were collected for cytology. Frequency of cultivatable bacteria before (Swab 1) and after (Swab 2) application of proparacaine or saline was compared using Fisher's exact test. Homogeneity of culture and cytology results was assessed using McNemar's test., Results: No difference was detected in number of animals from which bacteria were isolated from Swab 1 or Swab 2 for proparacaine (21/37 and 17/37, respectively) or saline (10/27 and 12/27, respectively). Small numbers prevented analysis of fungal culture results in horses between Swab 1 and Swab 2 for proparacaine (2/12 and 1/12, respectively) or saline (both, 1/8). Bacteria were isolated from 10 of 20 horses and detected cytologically in 3 of these; fungi were isolated from 3 of 20 horses and detected cytologically in 2 of these. Bacteria were detected more frequently using culture (31/64) than cytology (19/64)., Conclusion: Proparacaine did not significantly alter bacterial or fungal culture results in cats, dogs, or horses; however, clinical significance warrants investigation. Culture and cytology provided complementary data; both should be performed to maximize organism detection in patients with ulcerative keratitis., (© 2018 American College of Veterinary Ophthalmologists.)

Objectives: In humans with herpetic disease, early or pre-emptive famciclovir therapy reduces disease duration and severity. This prospective, masked, placebo-controlled study tested therapeutic and prophylactic effects of two famciclovir doses given to cats for 7 days following shelter entry., Methods: Cats were assigned to prophylactic or therapeutic study arms based on clinical evidence of herpetic disease at study entry. Cats in the therapeutic arm received no treatment (n = 19), placebo (lactose; n = 18) or famciclovir at ~30 (n = 21) or ~90 mg/kg (n = 20) PO q12h for 7 days. Cats in the prophylactic arm received no treatment (n = 25) or famciclovir at ~30 (n = 28) or ~90 mg/kg (n = 27) PO q12h for 7 days. Disease scores, body weight, conjunctival feline herpesvirus 1 (FHV-1) shedding, and adoption rates were recorded on days 1 (admission), 8 (end of therapy) and 15 (1 week after cessation of therapy)., Results: No significant differences in clinical scores were observed among groups in the prophylactic or therapeutic arms at any of the three time points. However, within the therapeutic arm, viral shedding on day 8 was significantly higher in cats receiving no treatment than in those receiving ~30 or ~90 mg/kg famciclovir, and this effect persisted 1 week after famciclovir was stopped (day 15) only in cats receiving ~30 mg/kg, although this approached significance in cats receiving ~90 mg/kg. No significant differences in adoption rates were detected among groups in either arm throughout the study., Conclusions and Relevance: Although we did not demonstrate a statistically or clinically significant effect of famciclovir administration upon clinical signs of infectious upper respiratory disease or adoption, when it was administered at ~30 or ~90 mg/kg q12h for 1 week famciclovir reduced conjunctival FHV-1 shedding. This suggests a potential role in interrupting the infectious cycle within a shelter population; however, cost in time and resources, and stress and pathogen transmission induced by oral administration should be considered.

Case Series Summary: Described are 13 cats diagnosed with deep ulcerative keratitis and successfully managed medically without grafting procedures. Typical treatment involved frequent topical application of serum and antibiotics (usually a fluoroquinolone and a cephalosporin). Seven cats also received systemic antibiotics. Analgesia was achieved using various combinations of topical atropine and systemic buprenorphine, robenacoxib or corticosteroids. Six cats were hospitalized for a median (range) period of 2.5 (1-8) days, typically because of frequent medication administration. Median (range) follow-up time was 41.5 (9-103) days. Median (range) number of recheck examinations was 4 (2-6). Median (range) time to corneal re-epithelialization was 21 (9-103) days. Median (range) topical antibiotic course was 29.5 (16-103) days. Median (range) duration of Elizabethan collar use was 28 (13-73) days. At the time of writing, no further recheck examinations were recommended for 10 cats; median (range) time between initial to final examinations in these cats was 35 (20-103) days. All cats retained the affected globes and were apparently comfortable and visual at the latest recheck examination., Relevance and Novel Information: These cases reveal that aggressive medical management is highly successful in select cats with deep ulcerative keratitis, and can result in a cosmetically acceptable, apparently comfortable and visual globe. However, therapy is intensive with frequent administration of multiple topical and sometimes systemic medications, and requires multiple veterinary visits over many weeks. Referral to a veterinary ophthalmologist for consideration of surgical stabilization is recommended, as not all cases may be amenable to the medical therapy described here.

Objective: To compare the effectiveness of retrobulbar anesthesia (RBA) and peribulbar anesthesia (PBA) in dogs., Animal Studied: Six adult mixed-breed dogs (18-24 kg)., Procedures: In a randomized, masked, crossover trial with a 10-day washout period, each dog was sedated with intravenously administered dexmedetomidine and administered 0.5% bupivacaine:iopamidol (4:1) as RBA (2 mL via a ventrolateral site) or PBA (5 mL divided equally between ventrolateral and dorsomedial sites). The contralateral eye acted as control. Injectate distribution was evaluated by computed tomography. Following intramuscularly administered atipamezole, corneal and periocular skin sensation, intraocular pressure (IOP), and ocular reflexes, and appearance were evaluated for 24 hours. Comparisons were performed with mixed-effects linear regression (IOP) or the exact Wilcoxon signed rank test (scores). Significance was set at P ≤ .05., Results: Injectate distribution was intraconal in 2/6 RBA- and 4/6 PBA-injected eyes. Eyes undergoing PBA had significantly reduced lateral, ventral, and dorsal periocular skin sensation for 2-3 hours, and significantly reduced corneal sensitivity for 4 hours, relative to control eyes. Chemosis and exophthalmos occurred in 33%-40% of eyes undergoing RBA and 83%-100% eyes undergoing PBA but resolved within 14 hours. Anterior uveitis developed in 2/6 and 1/6 eyes of RBA and PBA, respectively, of them corneal ulcer developed in one eye of each treatment. Both resolved 1-3 days following medical treatment., Conclusions: Peribulbar injection produced notable anesthesia more reliably than did retrobulbar injection. Both techniques may produce adverse effects, although the uveitis/ulcer could have resulted from the contrast agent used., (© 2018 American College of Veterinary Ophthalmologists.)

Purpose: To assess safety and tolerability of a subconjunctival penciclovir implant in cats infected with feline herpesvirus type 1 (FHV-1)., Methods: Subconjunctival blank (n = 4 cats) or penciclovir-impregnated (n = 6) silicone implants were placed bilaterally in 10 normal, FHV-1-naive cats 7-8 days before viral inoculation. Outcomes included disease score, FHV-1 serology, conjunctival viral load, Schirmer tear tests (STT), tear film break-up times (TFBUTs), conjunctival histology, goblet cell density (GCD), body weight, tear and plasma penciclovir concentration, and corneal ulcer evaluation., Results: Both groups had similar clinical and histologic disease scores, STT values, TFBUTs, GCD, FHV-1 titers, viral loads, and body weight changes. No ocular or systemic signs of toxicity were noted. Tear penciclovir concentration varied widely among cats and across time points. Tear penciclovir concentrations exceeded the lowest published half maximal inhibitory concentration (IC 50 ) in 5/6 treated cats. Plasma penciclovir concentrations remained below 10 ng/mL. Cats with higher tear penciclovir concentrations at inoculation and/or time of peak disease had fewer corneal ulcers than cats in which tear penciclovir concentrations were inconsistent, low, or unrecordable., Conclusions: Subconjunctival blank and penciclovir-impregnated implants were well tolerated at the ocular surface and not associated with systemic toxicity, adverse effect, or appreciable plasma penciclovir concentrations. Tear penciclovir concentrations >IC 50 were sometimes achieved, especially during burst release soon after implant placement. Further study is necessary to determine efficacy of locally delivered penciclovir when penciclovir concentration is consistently maintained above IC 50 . This will be especially useful in patients unable to receive systemic therapy.

Objective: To estimate the prevalence of ocular disease and obtain normative ocular data for free-living hummingbirds., Animals Studied: Two hundred and sixty-three free-living, adult Hummingbirds from coastal and inland central California were studied, including Anna's (Calypte anna, n = 186) and Black-chinned (Archilochus alexandri; n = 77) hummingbirds., Procedures: Slit lamp biomicroscopy and indirect ophthalmoscopy were performed on all individuals. Rebound tonometry, measurement of horizontal palpebral fissure length, and streak retinoscopy were performed on select individuals. Five conscious Anna's Hummingbirds underwent ocular imaging including fundus photography, digital slit lamp photography, and anterior segment and retinal optical coherence tomography., Results: The prevalence of ocular disease in this population was 2.28%. Ocular imaging revealed a thin cornea, shallow anterior chamber, large lens, and a single central, deep convexiclivate fovea. Mean ± SD intraocular pressure was 11.21 ± 2.23 mm Hg. Mean ± SD eyelid length was 2.59 ± 0.19 mm. All eyes were emmetropic or mildly hyperopic with a mean (range) ± SD refractive error of +0.32 (-0.25 to +1) ± 0.33 diopters., Conclusions: Consistent with previous reports, these data suggest that hummingbirds have visual characteristics found in predatory and prey species, as well as a low prevalence of spontaneous ocular disease. This work provides a set of reference values and clinical findings that can be used in the future research on hummingbird vision and ocular disease. It also provides representative diagnostic images of normal birds and demonstrates that advanced ocular imaging can be performed on manually restrained hummingbirds without pharmacologic dilation., (© 2018 American College of Veterinary Ophthalmologists.)

OBJECTIVE To describe and evaluate outcomes of a multidisciplinary, minimally invasive approach combining lacrimoscopy and fluoroscopically guided stenting for management of nasolacrimal apparatus (NLA) obstruction in dogs. DESIGN Prospective, nonrandomized clinical trial. ANIMALS 16 client-owned dogs with confirmed NLA obstruction. PROCEDURES Dogs underwent CT contrast dacryocystorhinography, rhinoscopy, and lacrimoscopy. Whenever possible, the NLA was stented, typically with fluoroscopic guidance. RESULTS Median duration of clinical signs prior to treatment was 3.2 months (range, 0.2 to 14 months). Causes of NLA obstruction were a foreign body (n = 5), dacryocystitis (4), stenosis secondary to fibrosis (3), granulation tissue (1), or granulation tissue in association with a small foreign body (1); a cause was not identified in 2 dogs. Stents were placed in 14 of 16 (88%) dogs for a median duration of 5.6 weeks (range, 1.3 to 9.4 weeks). Stenting was not possible in 2 dogs with stenosis of the NLA secondary to granulation tissue or fibrosis. Owners of all 16 dogs reported at least 60% clinical improvement with median improvement rated as 95%, and owners of 8 dogs reporting complete resolution of signs. Two dogs required antimicrobial administration because of dacryocystitis that persisted after stent removal; a foreign body was not found in either dog. CONCLUSIONS AND CLINICAL RELEVANCE Overall clinical response and owner-rated improvement for dogs with NLA obstruction that underwent lacrimoscopy and fluoroscopically guided stenting were high, especially given that these dogs had failed to respond to conventional treatment.

Objective: To determine factors associated with sudden acquired retinal degeneration syndrome (SARDS) diagnosed within one referral population., Animals Studied: 151 dogs diagnosed with SARDS., Procedures: Breed, age, sex, and body weight were compared between dogs with electroretinogram-confirmed SARDS and dogs presented to the UC Davis Veterinary Medical Teaching Hospital (UCD-VMTH) from 1991 to 2014., Results: SARDS was diagnosed in 151 dogs, representing 1.3% of dogs presented to the UCD-VMTH for ophthalmic disease. Although dogs of 36 breeds were affected, the Dachshund (n = 31, 21%), Schnauzer (16, 11%), Pug (11, 7%), and Brittany (5, 3%) were significantly overrepresented, and the Labrador Retriever (3, 2%) was significantly underrepresented vs. the reference population (P < 0.001). Median (range) age and body weight of affected vs. reference dogs were 8.9 (3-20) vs. 6.8 (0.1-26) years and 12.4 (2.8-52.7) vs. 22.3 (0.1-60) kg, respectively. Dogs 6-10 years of age and between 10-20 kg in body weight were significantly overrepresented in the SARDS population, while dogs <6 years of age were significantly underrepresented (P < 0.01). Spayed females (59% of affected dogs) were significantly overrepresented compared to the reference population, whereas intact females (1% of affected dogs) were significantly underrepresented., Conclusions: Consistent with previous studies, smaller, middle-aged, spayed female dogs may be at increased risk of developing SARDS. Unlike previous studies, this is the first study comparing a variety of SARDS-affected breeds to a reference population. Potentially increased risk of SARDS in several breeds, particularly Dachshunds, suggests a familial factor that warrants further investigation using genetic techniques., (© 2017 American College of Veterinary Ophthalmologists.)

Case series summary This case series describes the clinical utility of antigen testing for the diagnosis of feline ocular histoplasmosis. Four cats with suspected (n = 2) or confirmed (n = 2) ocular histoplasmosis are described: three from Oklahoma and one from California. In one case, serial urine antigen tests, as well as a serum antigen test for Histoplasma capsulatum, were negative; however, light microscopy identified microorganisms consistent with H capsulatum in ocular tissues at necropsy. In a further two cats with recurrent ocular histoplasmosis following long-term systemic antifungal therapy, Histoplasma species urine antigen concentrations were negative, but both cats improved clinically following systemic antifungal therapy and remained in apparent clinical remission after treatment cessation (9-16 months). The final cat displayed profound bilateral endophthalmitis; however, Histoplasma species antigen testing of vitreous humor and subretinal fluid from the left eye was negative. Intralesional organisms were detected on histopathology of both eyes, and H capsulatum was subsequently isolated and sequenced from tissue of one eye. Relevance and novel information These cases highlight the potential difficulty in definitively diagnosing ocular histoplasmosis in cats when conducting antigen testing of serum, urine and even ocular fluids. Although antigen testing has previously proven useful in the diagnosis of disseminated feline histoplasmosis, it may not be adequate in cats with only ocular signs.

Objective: To evaluate repeatability and reproducibility of tear osmolarity measured using the TearLab ™ osmometer in normal dogs and to assess its diagnostic potential in dogs with keratoconjunctivitis sicca (KCS)., Animals Studied: Beagle dogs; six normal and five with KCS., Procedures: Tear osmolarity and Schirmer tear test-1 (STT-1) values were obtained at various times. Normal dogs were assessed for diurnal variation and repeatability and reproducibility of measurements. Dogs with KCS were evaluated before and after 5 months' topical twice-daily therapy with 2% cyclosporine., Results: Mean ± SD tear osmolarity (mOsm/L) was significantly higher in normal dogs (337.4 ± 16.2) than in dogs with KCS before therapy (306.2 ± 18.0; P < 0.0001), but not following therapy with 2% cyclosporine (330.5 ± 13.7; P = 1.00). Osmolarity readings lower than 325.5 mOsm/L were suggestive of KCS (84.8% sensitivity and 87.1% specificity). In normal dogs, tear osmolarity readings were stable during the daytime (P = 0.99). Repeated measurements revealed high variability and typically poor-to-moderate repeatability and reproducibility, although this was improved by taking three successive measurements at each session. Considering combined data from all dogs, a positive correlation existed between STT-1 and tear osmolarity measurements (Pearson's correlation test, P = 0.04, r = 0.62)., Conclusions: Canine tear osmolarity as determined by TearLab ™ osmometer was variable, required multiple readings to be informative, and differed from values reported for humans. Dogs with KCS had a lower tear osmolarity than did normal dogs, and this increased following cyclosporine therapy., (© 2016 American College of Veterinary Ophthalmologists.)

Objective: To compare injectate distribution and likelihood of regional anesthesia to the orbit following retrobulbar (RB) or peribulbar (PB) injections in dog cadavers., Study Design: Randomized, masked study., Animals: Twenty-four dog cadavers (aged 5.5-17 years, 2.0-36.3 kg)., Methods: Orbits underwent one of three injection techniques with bupivacaine 0.5% and iohexol (1:1): ventrolateral RB injection (1-2 mL; 15 orbits), medial canthal PB injection (2-8 mL; PB-1; 16 orbits), or dorsomedial and ventrolateral PB injections (each 1-4 mL; PB-2; 16 orbits). The likelihood of successful regional anesthesia was estimated based on computed tomographic images scored for injectate volume of distribution at the base and within the extraocular muscle cone (EOMC), and injectate distribution around the optic nerve. Intraocular pressure (IOP) was measured before and after injections. Mixed-effects linear regression with post hoc Bonferroni contrast adjustments was performed. Significance was set at 0.05., Results: A difference in injectate volume of distribution within or at the base of the EOMC was not detected among groups. The median optic nerve circumference of injectate distribution was significantly higher in the RB injected group than in the PB-2 group. Injectate distribution following RB, PB-1 and PB-2 injections was graded as likely to provide regional anesthesia within the EOMC in 40%, 19% and 31% of eyes, and at the EOMC base in 60%, 63% and 50% of eyes, respectively. The probability of likelihood to provide regional anesthesia was lower in dogs of higher body weights. The IOP was significantly higher than baseline following PB-1 (18 ± 14 mmHg) and in comparison with RB (2 ± 3 mmHg), but not different from PB-2 injection (10 ± 11 mmHg)., Conclusions and Clinical Relevance: None of the techniques reliably produced 'successful' injectate distribution based on this study's definitions; however, clinical assessment of anesthetic success is required., (Copyright © 2017 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.)

Objective: To characterize grossly, histologically, and via computed tomography (CT) the appearance of intrascleral cartilage, bone, or both in domestic goats with otherwise normal eyes and to correlate this with age, sex, and breed., Animals Studied: Sixty-eight domestic goats (89 eyes)., Procedures: Forty-nine formalin-fixed globes from 38 goats underwent high-resolution CT, and gross and light microscopic examination. An additional 40 eyes from 30 goats underwent light microscopy only. Age, breed, and sex of affected goats were retrieved from medical records., Results: Considering all methods of evaluation collectively, cartilage was detected in 42% of eyes (44% of goats) and bone in 11% of eyes (12% of goats); bone was never seen without cartilage. Goats in which bone, cartilage, or both were detected ranged from 0.25 to 13 (median = 3.5) years of age, represented 11 of 12 breeds of the study population, and had a male:female ratio of 11:19. Bone was detected in the eyes of significantly more males (n = 8) than females (n = 2). No sex predilection was noted for cartilage alone. Histology revealed intrascleral chondrocyte-like cells, hyaline cartilage, and islands of lamellar bone. Some regions of bone had central, adipose-rich, marrow-like cavities. CT localized mineralized tissue as adjacent to or partially surrounding the optic nerve head., Conclusions: This is the first report of intrascleral bone or cartilage in a normal goat and of intrascleral bone in an otherwise normal mammal. The high prevalence of intrascleral cartilage and bone in this study suggests that this finding is normal and likely represents an adaptation in goats., (© 2016 American College of Veterinary Ophthalmologists.)

OBJECTIVE To assess the effects of topical application of undiluted heterologous serum on time to corneal reepithelialization in dogs with superficial chronic corneal epithelial defects (SCCEDs). DESIGN Multicenter, randomized, double-masked, controlled clinical trial. ANIMALS 41 client-owned dogs. PROCEDURES After collection of baseline clinical and historical data, dogs were randomly assigned to receive topically applied undiluted heterologous serum (n = 22) or isotonic saline (0.9% NaCl) solution (19) along with tobramycin and atropine. Epithelial debridement (at all visits) and grid keratotomy (at visits 2, 3, and 4) of SCCEDs were performed. Ophthalmic examination including fluorescein application was performed once weekly for 4 weeks or until corneal reepithelialization. Clinicians and owners were masked to treatment group. RESULTS No differences in baseline data were detected between treatment groups. No difficulties with medication administration, noncompliance, or adverse reactions were noted. All SCCEDs in both groups healed by 4 weeks after treatment began. Median time to reepithelialization (2 weeks) was not significantly different between serum-treated and placebo-treated eyes. Irrespective of treatment group, median time to reepithelialization was not significantly different for Boxers versus non-Boxer breeds. Direct correlations were detected between time to reepithelialization and vascularization score at study entry, vascularization score at time of reepithelialization, and ulcer area at study entry in both groups. Time to reepithelialization was not correlated with age, sex, or duration of signs in either group. CONCLUSIONS AND CLINICAL RELEVANCE Topical application of undiluted heterologous serum was well tolerated by dogs with SCCEDs but, as an adjunct to standard treatment, did not reduce time to corneal reepithelialization.

Objective: To compare signalment, presentation, treatment, and outcome in horses diagnosed with corneal degeneration (CD) or calcific band keratopathy (CBK) at a referral hospital., Animals Studied: Sixty-nine horses (87 eyes) diagnosed with either CD or CBK., Procedures: Medical records of horses diagnosed with CD or CBK at the University of California-Davis Veterinary Medical Teaching Hospital (UCD-VMTH) between 2000 and 2013 were reviewed. Signalment, concurrent ophthalmic diagnoses, previous therapies, diagnostic tests, systemic diagnoses, treatment, follow-up, and outcomes were compared between horses diagnosed with CD or CBK. Age, breed, and gender were compared between the CD/CBK and UCD-VMTH populations., Results: Thirty-three horses (42 eyes) and 36 horses (45 eyes) were diagnosed with CD and CBK, respectively. Horses with CD or CBK were significantly older (P < 0.001) than the UCD-VMTH population with a median age of 16 or 18 years, respectively. Appaloosas were significantly overrepresented in the CD/CBK population (33%) in comparison with the UCD-VMTH population (1.8%, P < 0.001). Equine recurrent uveitis was concurrently diagnosed in 67% and 84% of horses with CD or CBK, respectively. Pituitary pars intermedia dysfunction (PPID) was diagnosed significantly less often in horses with CD vs. CBK (P = 0.03). Chemical chelation with ethylenediaminetetraacetic acid was performed significantly less frequently in horses diagnosed with CD (7.1%) vs. CBK (31.1% of eyes) (P = 0.012)., Conclusions: Despite some differences, equine CD and CBK are relatively similar conditions and may represent a continuum of disease severity. Horses with PPID should be monitored closely for corneal disease including CBK., (© 2016 American College of Veterinary Ophthalmologists.)

OBJECTIVE To evaluate outcomes for cats treated with orally administered famciclovir 3 times/d for clinical signs attributed to naturally occurring feline herpesvirus type 1 (FHV-1) infection and to assess variables related to owner satisfaction with the treatment. DESIGN Retrospective case series. ANIMALS 59 client-owned cats. PROCEDURES Medical records were reviewed to identify cats treated for presumed FHV-1 infection from 2006 through 2013 with ≥ 1 follow-up visit. Signalment, duration of clinical signs, prior treatment, examination findings, diagnostic test results, concurrent treatments, and outcome data were recorded. Owners were asked to complete a survey regarding patient- and treatment-related variables. Data were compared between cats that received low (approx 40 mg/kg [18 mg/lb]) and high (approx 90 mg/kg [41 mg/lb]) doses of famciclovir, PO, 3 times/d. RESULTS Patient age ranged from 0.03 to 16 years. Conjunctivitis (51/59 [86%]), keratitis (51 [86%]), blepharitis (19 [32%]), nasal discharge or sneezing (10 [17%]), and dermatitis (4 [7%]) were common findings. Clinical improvement was subjectively graded as marked in 30 (51%) cats, mild in 20 (34%), and nonapparent in 9 (15%). Median time to improvement was significantly shorter, and degree of improvement was significantly greater in the highdose group than in the low-dose group. Adverse effects potentially attributable to famciclovir administration were reported for 10 cats. On the basis of survey responses, most (29/32 [91%]) owners were satisfied with their cat's treatment. CONCLUSIONS AND CLINICAL RELEVANCE Famciclovir at the prescribed dosages was associated with improved clinical signs in cats with presumed FHV-1 infection, and few adverse effects were attributed to the treatment. Further studies are needed to assess whether a famciclovir dosage of 90 versus 40 mg/kg, PO, 3 times/d would result in increased efficacy and shorter treatment time.

OBJECTIVES To determine, following oral administration of famciclovir, pharmacokinetic (PK) parameters for 2 of its metabolites (penciclovir and BRL42359) in plasma and tears of healthy cats so that famciclovir dosage recommendations for the treatment of herpetic disease can be optimized. ANIMALS 7 male domestic shorthair cats. PROCEDURES In a crossover study, each of 3 doses of famciclovir (30, 40, or 90 mg/kg) was administered every 8 or 12 hours for 3 days. Six cats were randomly assigned to each dosage regimen. Plasma and tear samples were obtained at predetermined times after famciclovir administration. Pharmacokinetic parameters were determined for BRL42359 and penciclovir by compartmental and noncompartmental methods. Pharmacokinetic-pharmacodynamic (PK-PD) indices were determined for penciclovir and compared among all dosage regimens. RESULTS Compared with penciclovir concentrations, BRL42359 concentrations were 5- to 11-fold greater in plasma and 4- to 7-fold greater in tears. Pharmacokinetic parameters and PK-PD indices for the 90 mg/kg regimens were superior to those for the 30 and 40 mg/kg regimens, regardless of dosing frequency. Penciclovir concentrations in tears ranged from 18% to 25% of those in plasma. Administration of 30 or 40 mg/kg every 8 hours achieved penciclovir concentrations likely to be therapeutic in plasma but not in tears. Penciclovir concentrations likely to be therapeutic in tears were achieved only with the two 90 mg/kg regimens. CONCLUSIONS AND CLINICAL RELEVANCE In cats, famciclovir absorption is variable and its metabolism saturable. Conversion of BRL42359 to penciclovir is rate limiting. The recommended dosage of famciclovir is 90 mg/kg every 12 hours for cats infected with feline herpesvirus.

Objective: To determine histologic and immunohistochemical predictors of metastasis of feline diffuse iris melanoma (FDIM)., Animals: Globes from 47 client-owned cats enucleated for FDIM between January 1985 and December 2013., Procedures: Hematoxylin and eosin-stained sections were evaluated for neoplastic invasiveness and cell morphology, necrosis within the neoplasm, inflammation, and glaucoma. Sections were immunolabeled with antibodies against melan-A, PNL2, E-cadherin, or B-Raf, and label intensity, percentage of labeled cells, and label homogeneity were semi-quantitatively graded. Medical records were evaluated, and referring veterinarians and clients were contacted to determine whether cats developed metastasis following enucleation. The log-rank test or Cox proportional hazards model was used to determine associations between histologic or immunohistochemical parameters and metastasis., Results: Metastasis was suspected or confirmed in 9/47 (19%) cats. Extrascleral extension, necrosis within the neoplasm, a mitotic index of >7 mitoses in 10 high-power (×400) fields, choroidal invasion, and increased E-cadherin and melan-A label intensity were each associated with increased rate of metastasis. PNL2 label homogeneity was associated with decreased rate of metastasis. Decreased PNL2 label intensity and an increasing percentage of neoplastic cells labeled for melan-A each approached significance for increased rate of metastasis., Conclusions: We report four histologic and three immunohistochemical parameters helpful in determining cats at risk of metastasis of FDIM. Further studies should determine if B-Raf mutations identified in human malignant melanomas are found in cats with FDIM and assess benefits of adjunctive therapy following enucleation of eyes with FDIM bearing poor prognostic indicators., (© 2016 American College of Veterinary Ophthalmologists.)

Objective: The aim of this study was to evaluate goblet cell density (GCD) and distribution in cats without clinical evidence of ocular surface disease and without histologic evidence of conjunctival disease., Animals Studied: Fourteen Domestic Shorthair cats euthanized for reasons unrelated to this study., Procedures: Before euthanasia, cats were verified using slit-lamp biomicroscopy and fluorescein staining to be free of eyelid or ocular surface abnormalities. Immediately after euthanasia, bilateral conjunctival specimens including third eyelid (TEL) were collected, routinely processed, and stained with periodic acid-Schiff and hematoxylin and eosin. Thirteen conjunctival regions were identified. For each region, GCD was expressed as the percentage of goblet cells/200 basal epithelial cells., Results: Mean GCD ranged widely by region: anterior surface of the TEL = 48.8%, fornicial regions = 47.0%, palpebral regions = 38.5%, bulbar regions = 19.6%, and posterior surface of the TEL = 12.6%. The anterior surface of the TEL had significantly higher GCD than did the bulbar and the palpebral regions, but not the fornicial regions. Bulbar conjunctiva had significantly lower GCD than did all other conjunctival regions except the posterior surface of the TEL. No significant difference was noted between GCD of male versus female cats, dorsal versus ventral regions, or lateral versus medial regions., Conclusions: Although conjunctival GCD ranged widely by region, the anterior surface of the TEL appears to be an excellent location for assessing conjunctival goblet cells in cats because this area has high GCD and is more readily accessible than is the palpebral, fornicial, or bulbar conjunctiva., (© 2016 American College of Veterinary Ophthalmologists.)

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., (© 2015 American College of Veterinary Ophthalmologists.)

Feline herpesvirus type 1 (FHV-1) is a common and important cause of ocular surface disease, dermatitis, respiratory disease, and potentially intraocular disease in cats. Many antiviral drugs developed for the treatment of humans infected with herpesviruses have been used to treat cats infected with FHV-1. Translational use of drugs in this manner ideally requires methodical investigation of their in vitro efficacy against FHV-1 followed by pharmacokinetic and safety trials in normal cats. Subsequently, placebo-controlled efficacy studies in experimentally inoculated animals should be performed followed, finally, by carefully designed and monitored clinical trials in client-owned animals. This review is intended to provide a concise overview of the available literature regarding the efficacy of antiviral drugs and other compounds with proven or putative activity against FHV-1, as well as a discussion of their safety in cats., (© 2016 American College of Veterinary Ophthalmologists.)

Background: The reduced cost and improved efficiency of whole genome sequencing (WGS) is drastically improving the development of cats as biomedical models. Persian cats are models for Leber's congenital amaurosis (LCA), the most severe and earliest onset form of visual impairment in humans. Cats with innocuous breed-defining traits, such as a bobbed tail, can also be models for somite segmentation and vertebral column development., Methods: The first WGS in cats was conducted on a trio segregating for LCA and the bobbed tail abnormality. Variants were identified using FreeBayes and effects predicted using SnpEff. Variants within a known haplotype block for cat LCA and specific candidate genes for both phenotypes were prioritized by the predicted variant effect on the proteins and concordant segregation within the trio. The efficiency of WGS of a single trio of domestic cats was evaluated., Results: A stop gain was identified at position c.577C > T in cat AIPL1, a predicted p.Arg193*. A c.5A > G variant causing a p.V2A was identified in HES7. The variants segregated concordantly in a Persian - Japanese bobtail pedigree. Over 1700 cats from 40 different breeds and populations were genotyped for the AIPL1 variant, defining an allelic frequency in only Persian -related breeds of 1.15%. A sub-set of cats was genotyped for the HES7 variant, supporting the variant as private to the Japanese bobtail breed. Approximately 18 million SNPs were identified for application in cat research. The cat AIPL1 variant would have been considered a high priority variant for evaluation, regardless of a priori knowledge from previous genetic studies., Conclusions: This study represents the first effort of the 99 Lives Cat Genome Sequencing Initiative to identify disease--causing variants in the domestic cat using WGS. The current cat reference assembly is efficient for gene and variant identification. However, as the feline variant database improves, development of cats as biomedical models for human disease will be more efficient, providing an alternative, large animal model for drug and gene therapy trials. Undiagnosed human patients with early-onset blindness should be screened for this AIPL1 variant. The HES7 variant should further calibrate the somite segmentation clock.

Objectives: To determine the role of equine herpesvirus (EHV) in idiopathic keratoconjunctivitis in horses and to determine whether sample collection method affects detection of EHV DNA by quantitative polymerase chain reaction (qPCR)., Animals Studied: Twelve horses with idiopathic keratoconjunctivitis and six horses without signs of ophthalmic disease., Procedures: Conjunctival swabs, corneal scrapings, and conjunctival biopsies were collected from 18 horses: 12 clinical cases with idiopathic keratoconjunctivitis and six euthanized controls. In horses with both eyes involved, the samples were taken from the eye judged to be more severely affected. Samples were tested with qPCR for EHV-1, EHV-2, EHV-4, and EHV-5 DNA. Quantity of EHV DNA and viral replicative activity were compared between the two populations and among the different sampling techniques; relative sensitivities of the sampling techniques were determined., Results: Prevalence of EHV DNA as assessed by qPCR did not differ significantly between control horses and those with idiopathic keratoconjunctivitis. Sampling by conjunctival swab was more likely to yield viral DNA as assessed by qPCR than was conjunctival biopsy. EHV-1 and EHV-4 DNA were not detected in either normal or IKC-affected horses; EHV-2 DNA was detected in two of 12 affected horses but not in normal horses. EHV-5 DNA was commonly found in ophthalmically normal horses and horses with idiopathic keratoconjunctivitis., Conclusions: Because EHV-5 DNA was commonly found in control horses and in horses with idiopathic keratoconjunctivitis, qPCR was not useful for the etiological diagnosis of equine keratoconjunctivitis. Conjunctival swabs were significantly better at obtaining viral DNA samples than conjunctival biopsy in horses in which EHV-5 DNA was found., (© 2015 American College of Veterinary Ophthalmologists.)

Purpose: A form of retinal degeneration suspected to be hereditary was discovered in a family of Bengal cats. A breeding colony was established to characterize disease progression clinically, electrophysiologically, and morphologically, and to investigate the mode of inheritance., Methods: Affected and related cats were donated by owners for breeding trials and pedigree analysis. Kittens from test and complementation breedings underwent ophthalmic and neuro-ophthalmic examinations and ERG, and globes were evaluated using light microscopy., Results: Pedigree analysis, along with test and complementation breedings, indicated autosomal recessive inheritance and suggested that this disease is nonallelic to a retinal degeneration found in Persian cats. Mutation analysis confirmed the disease is not caused by CEP290 or CRX variants found predominantly in Abyssinian and Siamese cats. Ophthalmoscopic signs of retinal degeneration were noted at 9 weeks of age and became more noticeable over the next 4 months. Visual deficits were behaviorally evident by 1 year of age. Electroretinogram demonstrated reduced rod and cone function at 7 and 9 weeks of age, respectively. Rod responses were mostly extinguished at 14 weeks of age; cone responses were minimal by 26 weeks. Histologic degeneration was first observed at 8 weeks, evidenced by reduced photoreceptor numbers, then rapid deterioration of the photoreceptor layer and, subsequently, severe outer retinal degeneration., Conclusions: A recessively inherited primary photoreceptor degeneration was characterized in the Bengal cat. The disease is characterized by early onset, with histologic, ophthalmoscopic, and electrophysiological signs evident by 2 months of age, and rapid progression to blindness.

Objective: To determine reference values, intertest correlations, and test-retest repeatability of Schirmer tear test 1 (STT-1), phenol red thread test (PRTT), tear film breakup time (TFBUT), tear osmolarity, and meibometry in healthy cats., Design: Evaluation study., Animals: 135 healthy domestic cats aged 0.5 to 12.8 years., Procedures: Each test was performed once in 120 cats and repeated in 40. Pearson correlation was used to assess correlation among tests. Intraclass correlation coefficients (ICCs) and 95% limits of agreement (LOA) were used to evaluate test-retest repeatability., Results: Median (95% central range) values were 18 mm/min (9 to 34 mm/min) for STT-1, 29 mm/15 s (15 to 37 mm/15 s) for PRTT, 12.4 seconds (9.1 to 17.7 seconds) for TFBUT, 322 mOsm/L (297 to 364 mOsm/L) for osmolarity, and 32 meibometry units (MU; 11 to 114 MU) for peak meibometry value. The STT-1 and PRTT values were positively correlated. Age was weakly associated with TFBUT and osmolarity. Meibometry measurements were higher for strips that contacted the tear film (285 MU) than for those that touched the eyelid margin only (32 MU). All ICCs were < 0.75, and 95% LOA were wide., Conclusions and Clinical Relevance: Tear deficiency should be suspected in cats with STT-1 < 9 mm/min, PRTT < 15 mm/15 s, or TFBUT < 9 to 10 seconds. Generally poor correlation among tests suggested that thorough tear film analysis requires performance of multiple tests in concert. Relatively poor test-retest repeatability should be considered when repeated tests are used to monitor tear film dysfunction and response to treatment.

Objective: To describe the lacrimal system of snakes using contrast micro-computed tomography (micro-CT) with 3-dimensional reconstruction, fluorescein passage ('Jones') testing, histology, and gross dissection., Animals Studied: One royal python and 19 snake cadavers representing 10 species., Procedures: Direct observation following injection of fluorescein into the subspectacular space, micro-CT following injection of three contrast agents into the subspectacular space, gross dissection following injection of latex into the subspectacular space, and histopathology., Results: Injection of fluorescein confirmed patency, but not course of the lacrimal duct. Barium enabled clear visualization of the lacrimal duct, whereas two iodinated contrast agents proved inadequate. Collectively, micro-CT, anatomic dissections, and histology suggest tears are produced by a single, large, serous, retrobulbar gland, released into the subspectacular space via several ductules, and drained through a single punctum originating in the ventronasal subspectacular space, and the lacrimal duct, which takes one of three routes of variable tortuosity before opening into the oral cavity in close association with the opening of the duct of the vomeronasal organ., Conclusions: The ophidian lacrimal duct has a generally tortuous course, and the details of its anatomy are species-variable. The tortuous course of the duct likely predisposes snakes to duct occlusion and must be considered when planning medical and surgical interventions in snakes with pseudobuphthalmos and subspectacular abscessation., (© 2014 American College of Veterinary Ophthalmologists.)