Tumor-like lymphoplasmacytic conjunctivitis in the third eyelid in a dog.

This report aims to describe a case of tumor-like lymphoplasmacytic conjunctivitis in a 7-year-old spayed-female Pomeranian. On complete ophthalmic examination, a mass with papillary projections was noted on the bulbar surface of the right third eyelid. Debulking of the mass was performed while preserving as much of the third eyelid as possible. On the histopathological examination, the mass was diagnosed as lymphoplasmacytic conjunctivitis with mild epithelial hyperplasia. Although a slight regrowth of the mass was noted 3 weeks after surgery, intralesional injection of triamcinolone acetonide led to its disappearance. There was no further recurrence after 5 months.

Chlamydia suis survival in dust: First insights.

Chlamydia (C.) suis, a zoonotic intracellular bacterium, is described as a causative agent for conjunctivitis, particularly in nursery and fattening pigs. Chlamydiaceae are claimed to survive drying and to persist in dust. The objective of this study was to evaluate the viability of Chlamydia in dust sampled in a fattening pig farm with a high appearance of chlamydial-induced conjunctivitis. Dust was collected and stored at room temperature. To evaluate bacterial load and survival over time, quantitative PCR (Chlamydiaceae, C. suis) and isolation in cell culture were performed every week for up to 16 weeks. While qPCR results remained highly positive with consistent bacterial loads between 103 and 104 copy numbers/100 µL eluate over a period of 16 weeks and even after 40 weeks, it was not possible to isolate Chlamydia except for the initial sample. These results show only short-term viability of C. suis in dust. This is an important information regarding reduction of chlamydial loads in pig farms and risk for pigs and people to get infected via dust.

A case of lipogranulomatous conjunctivitis in a horse.

OBJECTIVE: To describe a case of lipogranulomatous conjunctivitis in a horse. ANIMAL STUDIED: A client-owned 12-year-old Standardbred gelding presenting with chronic conjunctivitis and palpebral masses. METHODS: Complete ophthalmic examination, surgical excision, histopathology, and bacterial culture of biopsy samples were performed. RESULTS: Upper and lower eyelids of both eyes were affected, with multiple yellow-to-white nodules on the palpebral conjunctiva, adjacent to the eyelid margin. Nodule removal was achieved via partial tarsal plate excision. Histopathological examination revealed granulomatous inflammation and large droplets of presumed free lipid in the conjunctival lamina propria. The animal was diagnosed with lipogranulomatous conjunctivitis. No postoperative ocular discomfort was observed for months; however, 3 years later, new conjunctival nodules were noticed, requiring a second surgical procedure on three of the eyelids. Transient entropion in the left lower eyelid was observed 2 months after the second surgery, and no recurrence of conjunctival nodules was observed after 18 months of follow-up. CONCLUSION: To our knowledge, this is the first report of lipogranulomatous conjunctivitis in horses.

Are Purple Finches (Haemorhous purpureus) the Next Host for a Mycoplasmal Conjunctivitis Epidemic?

Ever since 1994, when the bacterial pathogen Mycoplasma gallisepticum jumped from poultry to wild birds, it has been assumed that the primary host species of this pathogen in wild North American birds was the house finch (Haemorhous mexicanus), in which disease prevalence was higher than in any other bird species. Here we tested two hypotheses to explain a recent increase in disease prevalence in purple finches (Haemorhous purpureus) around Ithaca, New York. Hypothesis 1 is that, as M. gallisepticum evolved and became more virulent, it has also become better adapted to other finches. If this is correct, early isolates of M. gallisepticum should cause less-severe eye lesions in purple finches than in house finches, while more-recent isolates should cause eye lesions of similar severity in the two species. Hypothesis 2 is that, as house finch abundance declined following the M. gallisepticum epidemic, purple finches around Ithaca increased in abundance relative to house finches and purple finches are thus more frequently exposed to M. gallisepticum-infected house finches. This would then lead to an increase in M. gallisepticum prevalence in purple finches. Following an experimental infection with an early and a more-recent M. gallisepticum isolate, eye lesions in purple finches were more severe than in house finches. This did not a support Hypothesis 1; similarly, an analysis of Project Feeder Watch data collected around Ithaca did not show differences in changes in purple and house finches' abundance since 2006, a result which does not support Hypothesis 2. We conclude that purple finch populations will, unlike those of house finches, not suffer a severe decline because of a M. gallisepticum epidemic.

¿Son los pinzones purpúreos (Haemorhous purpureus) los próximos huéspedes de una epidemia de conjuntivitis por micoplasma? Desde el año 1994, cuando el patógeno bacteriano Mycoplasma gallisepticum saltó de las aves comerciales a las aves silvestres, se ha supuesto que la principal especie huésped de este patógeno en las aves silvestres de América del Norte era el pinzón mexicano (Haemorhous mexicanus), en el que la prevalencia de la enfermedad era mayor que en cualquier otra especie aviar. En este estudio se analizaron dos hipótesis para explicar un aumento reciente en la prevalencia de la enfermedad en los pinzones purpúreos (Haemorhous purpureus) alrededor de Ithaca, en Nueva York. La hipótesis 1 es que, a medida que M. gallisepticum evolucionó y se volvió más virulento, también se adaptó mejor a otros pinzones. Si esto es correcto, los aislamientos tempranos de M. gallisepticum deberían causar lesiones oculares menos graves en los pinzones purpúreos que en los pinzones mexicanos, mientras que los aislamientos más recientes deberían causar lesiones oculares de gravedad similar en las dos especies. La hipótesis 2 es que, a medida que la abundancia de pinzones mexicanos disminuyó después de la epidemia de M. gallisepticum, los pinzones purpúreos alrededor de Ithaca aumentaron en abundancia en relación con los pinzones mexicanos y, por lo tanto, los pinzones morados están expuestos con mayor frecuencia a los pinzones caseros infectados con M. gallisepticum. Esto conduciría a un aumento de la prevalencia de M. gallisepticum en los pinzones purpúreos. Después de una infección experimental con un aislamiento temprano y uno más reciente de M. gallisepticum, las lesiones oculares en los pinzones purpúreos fueron más graves que en los pinzones mexicanos. Esto no apoyó la Hipótesis 1; de manera similar, un análisis de los datos del Proyecto Feeder Watch recopilados alrededor de Ithaca no mostró diferencias en los cambios de la abundancia de pinzones purpúreos y mexicanos desde 2006, un resultado que no respalda la Hipótesis 2. Se concluye que las poblaciones de pinzones purpúreos, a diferencia de las de los pinzones mexicanos, no sufrieron un declive severo a causa de una epidemia de M. gallisepticum.

EFFECTS OF MYCOPLASMA GALLISEPTICUM INFECTION ON PREENING BEHAVIORS AND FEATHER QUALITY IN HOUSE FINCHES (HAEMORHOUS MEXICANUS).

Infections can have far-reaching sublethal effects on wildlife, including reduced maintenance of external structures. For many wildlife taxa, daily maintenance of external structures (termed preening in birds) is critical to fitness, but few studies have examined how infections alter such maintenance. Mycoplasma gallisepticum is a common pathogen in free-living House Finches (Haemorhous mexicanus), where it causes mycoplasmal conjunctivitis. Despite documented behavioral changes associated with M. gallisepticum infections in finches, no studies have examined how preening behavior may change with infection and how potential differences in preening may affect feather quality. To test this, we experimentally inoculated captive House Finches with M. gallisepticum or a control treatment, and we collected behavioral and feather quality data to detect potential changes in feather maintenance due to infection. We found that finches infected with M. gallisepticum preened significantly less often, and within the infected treatment, birds with the highest conjunctivitis severity preened the least often. However, there was no difference in the quality scores for secondary flight feathers collected from control versus infected birds. We also assayed feather water retention and found that the degree of water retention correlated with our feather quality scores, such that feathers with poor scores retained more water. However, as with quality scores, feather water retention did not differ with infection; this may be due to the controlled environment that the birds experienced while in captivity. Our data suggest that, in addition to sickness behaviors previously observed in finches, M. gallisepticum infection decreases other behaviors critical to survival, such as preening. While the consequences of reduced preening on feather maintenance were not apparent in captive conditions, further work is needed to determine whether House Finches in the wild that are infected with M. gallisepticum experience a fitness cost, such as increases in ectoparasite loads, due to this reduced feather maintenance.

Bilateral palpebral reduction and concurrent mycoplasmosis in a wild Agassiz's desert tortoise (Gopherus agassizii).

A wild Agassiz's desert tortoise, Gopherus agassizii, with bilateral eyelid reduction and plaques of tissue covering the superior surface of both corneas was examined in the field and subsequently submitted to the University of Florida for diagnostics. Polymerase chain reaction (PCR), from a swab of both corneas, was positive for Mycoplasma agassizii. Two months later, the tortoise was euthanatized and necropsied. There was increased bulbar exposure associated with dermal excoriation of periocular scales in both superior and inferior palpebra resulting in an increased palpebral fissure opening. Concurrently, there was bilateral conjunctivitis of the nictitating membranes and squamous metaplasia of the bulbar conjunctiva. Using PCR, Mycoplasma testudineum, another pathogen of tortoises, was identified in both nasal cavities, and the upper respiratory tract histopathological findings were consistent with those described for M. testudineum in Agassiz's desert tortoises. Although eye disease has been reported in desert and gopher (Gopherus polyphemus) tortoises with mycoplasmosis, widespread loss of palpebral tissue, conjunctivitis of the nictitans, and squamous metaplasia of the bulbar conjunctiva have not been reported in tortoises.

Eosinophilic Keratoconjunctivitis in Cats.

Eosinophilic keratitis is a disease of the feline ocular surface. It is characterized by conjunctivitis, white to pink raised plaques on the corneal and conjunctival surfaces, corneal vascularization, and variable ocular pain. Cytology is the diagnostic test of choice. Identification of eosinophils in a corneal cytology sample usually confirms the diagnosis, although lymphocytes, mast cells, and neutrophils are often present concurrently. Immunosuppressives are the mainstay of therapy, topically or systemically. The role of feline herpesvirus-1 in the pathogenesis of eosinophilic keratoconjunctivitis (EK) remains unclear. Eosinophilic conjunctivitis is a less common manifestation of EK and presents as severe conjunctivitis without corneal involvement.

Zoonotic potential of guinea pigs: Outbreak of cryptosporidiosis combined with chlamydiosis in a breeding guinea pig herd.

INTRODUCTION: In a guinea pig herd with 26 breeding animals, several individuals of all age categories died (16/26) after three animals had been newly introduced from another herd. Furthermore, the population suffered of apathy, anorexia, severe weight loss and conjunctivitis, as well as abortions and stillbirths. At the same time, the owner experienced a SARS-CoV-2 infection with pneumonia, which was confirmed by taking a PCR test. Chlamydia caviae was detected from the conjunctiva and vagina/uterus in one juvenile animal together with an intestinal Cryptosporidium wrairi infection. Oocysts were found histologically in the small intestine, which was confirmed by PCR. C. wairi is a parasite adapted to guinea pigs with zoonotic potential, which causes diarrhoea with frequent deaths in larger guinea pig herds. C. caviae is also a zoonotic pathogen and often the cause of conjunctivitis, pneumonia and abortions in guinea pigs and can lead to upper respiratory tract disease, conjunctivitis but also severe pneumonia in humans. The increased death cases and the clinical signs could be traced back to an infection with Cryptosporidium wrairi, complicated by a co-infection of C. caviae. We suspect that the abortions were caused by C. caviae, but since the population was treated with various antibiotics effective against chlamydial infections, it was no longer possible to verify this by PCR testing. Unfortunately, more animals succumbed and finally only two animals of the originally 26 were left. With this case report, we would like to point out to veterinarians that guinea pigs can be an important source of zoonotic infections for various pathogens, especially since they are popular pets and often come into close contact with children where hygiene might not always be strictly followed.

INTRODUCTION: Dans un groupe de cobayes de 26 animaux reproducteurs, plusieurs individus de toutes les catégories d'âge sont morts (16/26) après l'introduction de trois animaux provenant d'un autre groupe. En outre, la population a souffert d'apathie, d'anorexie, de perte de poids sévère et de conjonctivite ainsi que d'avortements et de mortinatalité. La présence de Chlamydia caviae a pu être détectée dans la conjonctive et le vagin/utérus d'un animal juvénile, ainsi qu'une infection intestinale à Cryptosporidium wrairi. Des oocystes ont été trouvés histologiquement dans l'intestin grêle, ce qui a été confirmé par PCR. C. wairi est un parasite adapté aux cobayes avec un potentiel zoonotique, qui provoque des diarrhées avec des morts fréquentes dans les grands groupes de cobayes. C. caviae est également un agent pathogène zoonotique et est souvent à l'origine de conjonctivites, de pneumonies et d'avortements chez les cobayes ; il peut entraîner des maladies des voies respiratoires supérieures, des conjonctivites mais aussi des pneumonies graves chez l'homme. L'augmentation des cas de décès et les signes cliniques pourraient être attribués à une infection par Cryptosporidium wrairi, compliquée par une co-infection par C. caviae. Nous soupçonnons que les avortements ont été causés par C. caviae, mais comme la population a été traitée avec divers antibiotiques efficaces contre les infections à chlamydia, il n'était plus possible de le vérifier par des tests PCR. Malheureusement, d'autres animaux ont succombé et il ne restait finalement que deux animaux sur les 26 d'origine. Avec ce rapport de cas, nous aimerions attirer l'attention des vétérinaires sur le fait que les cochons d'Inde peuvent être une source importante d'infections zoonotiques pour divers pathogènes, d'autant plus qu'il s'agit d'animaux de compagnie populaires qui sont souvent en contact étroit avec des enfants avec lesquels l'hygiène n'est pas toujours strictement respectée.

Cytological and microbiological evaluation of conjunctiva in camels with and without conjunctivitis.

OBJECTIVE: To describe the cytological analysis of conjunctiva from normal camels and camels with bacterial conjunctivitis. ANIMALS STUDIED: This study was conducted on 7 normal camels and 15 camels affected with conjunctivitis. The affected camels had a history of conjunctivitis with signs including chemosis, blepharospasm, frequent blinking, and mild-to-moderate serous, mucoid, or purulent ocular discharge. PROCEDURES: Bacterial swabs were collected from the inferior conjunctival sac of the affected eye without topical anesthetics. Conjunctival smears were obtained from the conjunctival surface for cytological analysis. RESULTS: The cellular analysis of ocular smears revealed a higher percentage of basal cells, neutrophils, eosinophils, and macrophages in camels with conjunctivitis compared with normal camels. In contrast to this, smears from normal camels showed an increased percentage of superficial epithelial cells compared with affected camels. The microbiological assessment of conjunctival swabs collected from affected animals identified a bacterial growth of Staphylococcus aureus., Bacillus sp., Streptococcus sp., Enterococcus faecium., Staphylococcus sp., Corynebacterium sp., Coryne pseudotuberculosis., Saprophytica, Enterobacter cloacae, Escherichia coli, Proteus mirabilis, Proteus vulagaris, and Pseudomonas aeruginosa. CONCLUSIONS: It was observed that bacterial conjunctivitis in camels was associated with increased percentages of basal epithelial cells, neutrophils, eosinophils, and macrophages compared with normal camels, while normal camels showed an increased percentage of superficial epithelial cells compared with affected camels.

Ocular lesions in cats diagnosed with systemic sporotrichosis.

OBJECTIVES: To describe the most common ocular lesions and demonstrate the frequency of ophthalmic involvement in a group of cats with systemic sporotrichosis. ANIMALS STUDIED: Two hundred seventy-four cats diagnosed with systemic sporotrichosis. The inclusion criteria included previous positive cytopathological examination, histopathological examination, or fungal culture. PROCEDURES: In a prospective case-control study, 274 cats diagnosed with systemic sporotrichosis underwent ophthalmic evaluation and received treatment for systemic sporotrichosis. Of these animals, 63 had ocular abnormalities which were recorded, and conjunctivitis was scored from 0 to 5. Diagnostic techniques utilized included fungal culture, as well as cytopathological (10 eyes; 10 cats), and histopathological examination of the palpebral conjunctiva and eyes (2 eyes). RESULTS: Cytopathological and histopathological examination of the conjunctiva, as well as fungal culture, proved to be important tests for the detection of Sporothrix sp. Five cats without the evidence of ophthalmic abnormalities also had a positive fungal culture. The identified ocular lesions in animals with systemic sporotrichosis included increased serous discharge (79 eyes; 53 cats), blepharoconjunctivitis (33 eyes; 25 cats), conjunctivitis (39 eyes, 20 cats), blepharitis (9 eyes; 8 cats), uveitis (5 eyes; 3 cats), and Florida keratopathy-like lesions (2 eyes; 1 cat). CONCLUSION: Sporotrichosis should be considered a differential diagnosis for conjunctivitis and blepharoconjunctivitis, especially in endemic areas. Fungal culture and cytopathology of ocular discharge and histopathological examinations of the conjunctiva are important for the diagnosis of ophthalmic sporotrichosis, although not all cats underwent laboratory testing in this study. Ocular discharge could be a source of contagion transmission.

Changes in tear production in a dog with keratoconjunctivitis sicca for a year after inevitable nictitating membrane gland resection due to suspicion of a malignant tumour.

Since the removal of the NM causes KCS in dogs, it was contraindicated to remove the NM unless unavoidable such as in a malignant tumour. However, to the best of author's knowledge, there are no reports of conjunctivitis and keratitis owing to decreased tear production following removal of the NM gland. This case study demonstrates the tear production changes in a dog for a year after removal of the nictitating membrane (NM) due to suspicion of a malignant tumour. A 13-year-old spayed female English Cocker Spaniel who had suffered from severe ocular discharge, discomfort, keratoconjunctivitis sicca (KCS), and NM enlargement in the right eye was brought to our hospital. The dog could not tolerate treatment with topical 0.2% cyclosporine or corticosteroids. The dog's right eye had NM gland prolapse, severe follicular conjunctivitis and a very low Schirmer tear test-1 (STT-1) value of 3 mm/min. Furthermore, the result of fine needle aspiration of the enlarged NM gland suggested a risk of malignancy. Despite the risk of KCS, complete NM resection was performed to diagnose the tumour. Fortunately, the final histopathological evaluation revealed chronic inflammation without any evidence of malignancy. Contrary to concerns that the STT-1 value would further decrease after the removal of the NM gland, the STT-1 value remained elevated compared to that before surgery, and the clinical symptoms improved for a year. It is generally known that NM gland resection is not recommended due to the risk of developing iatrogenic KCS unless a malignant tumour is suspected. In this case, surgical removal of the inflammatory NM gland that was not responsive to medications had a positive effect on KCS. Since the inflammatory and structural disease of the NM was strengthening KCS, the outcome was thought to be different from that when the normal third eyelid was removed.

Outbreak of follicular conjunctivitis associated with the diagnosis of anaplasmosis in a sheep herd.

OBJECTIVE: To report an outbreak of follicular conjunctivitis in a group of sheep diagnosed with Anaplasma spp., without any other co-infection. ANIMALS STUDIED: In all, 18 animals from a sheep head, males and females, from eight months to four years of age, were assessed for follicular conjunctivitis. PROCEDURES: The procedures performed included general physical and ophthalmological examinations; PCR evaluation for infectious agents; analysis of hematological parameters, microbiological tests of ocular swabs, coproparasitological examination, histopathological examination of conjunctival biopsy. RESULTS: All 18 animals had uni- or bilateral follicular conjunctivitis, and one animal also had unilateral uveitis. The results of microbiological analyzes were negative for Moraxella spp., Staphylococcus spp., and Pseudomonas spp., and PCR analysis results were negative for Chlamydia spp., Mycoplasma spp., and Toxoplasma gondii. Anemia, thrombocytopenia, lymphocytosis, and an inclusion body in some erythrocytes, compatible with Anaplasma and PCR analysis for Anaplasma spp. were positive. CONCLUSION: Anaplasmosis may be associated with follicular conjunctivitis in sheep and should be included in the differential diagnosis list and investigated in cases of conjunctivitis in herds.

Ocular abnormalities in the Icelandic horse with a focus on equine recurrent uveitis: 112 Icelandic horses living in Denmark and 26 Icelandic horses living in the United States.

PURPOSE: To describe the most common ocular abnormalities in the Icelandic horse with focus on equine recurrent uveitis (ERU) and association between ocular abnormalities and summer eczema and coat colors. METHODS: A descriptive cross-sectional study. A complete physical and ophthalmic examination as well as measurement of serum titers for Leptospira serovariants was performed on Icelandic horses from Denmark (DK) and the United States (USA). RESULTS: One hundred and twelve Icelandic horses living in DK and 26 Icelandic horses living in the United States were included in this study (total of 138 horses, 274 eyes). The three most common ocular abnormalities were follicular conjunctivitis (55.8%, 153/274 eyes), cataracts (27.4%, 75/274 eyes), and multifocal chorioretinopathy ("bullet holes"; 19%, 52/274 eyes). The prevalence for ERU among Icelandic horses aged "eight years and older" was 8% (6/75 horses). The "insidious ERU" type was found in 83% of the ERU cohort (5/6 horses), while "classic ERU" was found in 17% (1/6 horses). A correlation between ERU and cataracts was found in the population (p < .01). Leptospiral serology results were not associated with ERU in either DK or US-Icelandic horses (p = 1.00, p = 1.00, respectively). ERU was not associated with summer eczema (p = .49), and no coat colors were associated with the ocular abnormalities found in the Icelandic horse (all p-values > .05). CONCLUSION: Follicular conjunctivitis, cataracts, and multifocal chorioretinopathy were the three most common ocular abnormalities findings. Icelandic horses who were 8 years or older had an 8% prevalence for ERU. Summer eczema and coat color were not associated with evidence of ERU or other ocular abnormalities.

A large deletion in the Plasminogen gene is associated with ligneous membranitis in a Maltese dog.

Ligneous membranitis/conjunctivitis (LM, OMIM 217090) is a hereditary disorder caused by a congenital plasminogen (PLG) deficiency. In veterinary medicine, LM (OMIA 002020-9615) has rarely been reported in Golden Retrievers, Yorkshire Terriers, Doberman Pinschers and Scottish Terriers. In the latter breed, an A>T variation in an intron donor site of the PLG gene (PLG, c.1256+2T>A) has been found to be the sole causative molecular defect reported to date in dogs. Owing to the absence of plasmin enzymatic clearance which in turn depends on the lack of its proenzyme plasminogen, fibrin deposits tend to accumulate in viscous membranes on the eyes, triggering and sustaining an intense inflammatory response. A case of LM was diagnosed in a 7-month-old male Maltese dog. The dog was examined for severe recurrent conjunctivitis. A diagnosis of ligneous conjunctivitis was made by an ophthalmologist after a thorough eye examination and was confirmed by a complete lack of plasma activity of plasminogen. The main local signs were redness of the conjunctiva with persistent membranes having ligneous (wood-like) membranes on the eyes. The disease was associated with a complex rearrangement involving the plasminogen gene loci, causing the complete deletion of exon 1. This study provides a spontaneous animal model for LM associated with complete plasminogen deficiency and provides a method for detecting affected or carrier dogs.

Investigation of chlamydophilosis from naturally infected cats.

BACKGROUND: Chlamydophila felis, formerly known as Chlamydia psittaci var. felis, is frequently associated with ocular, respiratory, and occasionally reproduction tract infections. Even though the infection is sometimes asymptomatic, it potentially results in a latent immunosuppressive infection. OBJECTIVE: This study aimed to identify occurrences of feline chlamydophilosis, rarely reported in cats in Indonesia. METHODS: The observation was conducted in three cats with clinical signs of Cp. felis infection, particularly relapsing conjunctivitis. The cats' histories were recorded based on owners' information. Conjunctival swabs were sampled for cytology examination and molecular assay detection. A phylogenetic tree was generated using MEGA-X software to reveal group clustering. A post-mortem examination was performed on the cat that died during an examination. RESULTS: Cp. felis was detected in both cytological examination and polymerase chain reaction assay. The phylogenetic tree demonstrated that the Cp. felis isolated in this study clustered with several other isolates from the other countries. Cp. felis can be isolated from cats with different clinical manifestations and levels of severity. The chronic fatal infection demonstrated interstitial broncho-pneumonia under histopathological examination. CONCLUSIONS: Molecular assay of Cp. felis is always recommended to obtain a definitive diagnosis of feline chlamydophilosis since the disease can have various clinical manifestations. Even though it may be subclinical and is often not fatal, an infected cat may be a carrier that could spread the pathogen in the surrounding environment. Serious disease management is suggested to avoid high costs associated with regularly relapsing disease.

Impact of diurnal variation, sex, tear collection method, and disease state on tear protein levels in dogs.

OBJECTIVE: To investigate the effects of various biological factors on total protein concentration (TPC) and serum albumin levels in canine tears. ANIMALS STUDIED: 10 healthy beagles (5 female, 5 male) were used. PROCEDURES: Experiments were conducted on separate days, collecting tears with either capillary tubes or Schirmer strips, as follows: (i) Tear collection at 3 hours intervals (from 6 am to 12 am); and (ii) Tear collection before and 20 minutes following topical histamine application (1, 10, 375 mg/mL) to induce mild, moderate, and severe conjunctivitis, respectively. TPC and serum albumin were measured with infrared spectroscopy and ELISA, respectively. RESULTS: Tear film TPC and serum albumin ranged from 9.7-26.1 mg/mL and 6.4-1662.6 µg/mL, respectively. Protein levels did not differ significantly among time points (P ≥ .080). Median coefficient of variation (CV%) was lower with Schirmer strips compared to capillary tubes for both TPC (12% vs 15%, P = .020) and serum albumin (57% vs 78%, P = .232). TPC (P < .001), but not serum albumin was greater in male vs. female dogs. Serum albumin, but not TPC (P ≥ .099), increased significantly with each grade of conjunctivitis severity (P < .001), with no differences between collection devices (P ≥ .322); median increase was 106%, 1389%, and 2871% in eyes with mild, moderate, and severe conjunctivitis, respectively. CONCLUSIONS: There is no apparent diurnal variation in canine tear protein levels. Blood-tear barrier breakdown with conjunctivitis allows serum albumin to leak into the tear film at high concentrations. Schirmer strips compare well with capillary tubes for bioanalytical purposes in healthy and diseased eyes, and this collection method may offer improved reproducibility for protein quantification.

Impact of acute conjunctivitis on ocular surface homeostasis in dogs.

OBJECTIVE: To investigate the effects of acute conjunctivitis on tear film characteristics and corneal sensitivity in dogs. ANIMALS STUDIED: Eight female spayed Beagle dogs (1.5-2 years old, 7.5-10 kg). PROCEDURES: On two consecutive days, one randomly selected eye in each dog received 1 or 375 mg/mL histamine solution to induce mild or severe conjunctivitis, while the contralateral eye served as control. Diagnostic tests were performed in the following order: fluorescein instillation and repeated tear collection over 20 minutes (to determine tear volume [TV] and turnover rate [TTR] by fluorophotometry), Schirmer tear test-1 (STT-1), tear ferning, corneal esthesiometry, and tear film breakup time (TFBUT). RESULTS: Results are presented as median values for severe conjunctivitis, mild conjunctivitis, and control eyes. Eyes with severe conjunctivitis had significantly higher STT-1 (24, 19.5, 17.5 mm/min; P = .002) and significantly lower TFBUT (10.5, 13.5, 15.5 s; P = .002), but no changes were noted in corneal tactile sensation (2, 2.5, 2.5 cm) or tear ferning (grades 2, 2, 2.5). Severe conjunctivitis significantly increased TV by nearly 10-fold (631, 97, 65 µL) initially (reflex tearing), although basal TV returned rapidly (<5 minutes) in all eyes (46, 58, 48 µL). Finally, there was a nonsignificant trend for higher reflex TTR in the conjunctivitis vs control eyes (68, 58, 43%/min). CONCLUSIONS: Experimentally induced conjunctivitis increases tear quantity and decreases tear quality in dogs, but has no impact on corneal sensitivity. Changes in tear film dynamics could affect ocular pharmacology (eg, precorneal retention time), although homeostasis of lacrimal volume and drainage is rapidly restored.

Ocular findings and selected ophthalmic diagnostic tests in a group of young commercially available Guinea and Skinny pigs (Cavia porcellus).

OBJECTIVE: The purpose of this study is to evaluate a group of young commercially available Skinny pigs, to gain information regarding ocular findings in this breed of guinea pig. Comparisons of ocular findings are to be made between Skinny pigs and haired guinea pigs. ANIMAL STUDIED: Ten haired guinea pigs and ten Skinny pigs were examined. PROCEDURE: A complete ophthalmic examination including Schirmer tear test-II (STT-II), phenol red thread test (PRTT), rebound tonometry with TonoVet PLUS, Fluorescein and Rose Bengal stain was performed. Microbiology swabs for aerobic bacterial growth were collected from conjunctiva of both eyes prior to the ophthalmic examination. RESULTS: The ophthalmic examination revealed seven abnormal ocular findings: trichiasis, mucopurulent discharge, hyperemia/chemosis of the conjunctiva, corneal fibrosis, corneal vascularization, and foreign body on the cornea or conjunctiva. Skinny pigs had a significantly higher amount of mucopurulent discharge (P = .0133) and a significantly higher STT-II (P < .001) than haired guinea pigs. Although not significant, trichiasis, keratitis with corneal vascularization, and foreign body presence were more common in Skinny pigs. Significantly more Skinny pigs had Pasteurellaceae isolated from their conjunctiva than haired guinea pigs (P = .0112). Antimicrobial susceptibility for the five Pasteurellaceae organisms isolated revealed susceptibility toward oxytetracycline, tobramycin, ciprofloxacin, and ofloxacin, whereas resistance was found toward erythromycin, trimethoprim-sulfamethoxazole, and moxifloxacin. CONCLUSION: Young Skinny pigs have a higher risk of Pasteurellaceae-associated conjunctivitis. Oxytetracycline, tobramycin, ciprofloxacin, and ofloxacin were identified as topical antibiotics that may be useful for Pasteurellaceae-associated conjunctivitis in Skinny pigs.

Swine conjunctivitis outbreaks associated with Mycoplasma hyorhinis.

Conjunctivitis is an uncommon finding in commercial swine herds, and the etiology of the disease is rarely studied. We investigated cases of conjunctivitis in 3 wean-to-finish swine farms. Eye swabs and tissues were obtained from clinically affected pigs (8-22 wk of age), from unaffected pigs in contact with affected pen-mates, and from age-matched pigs from an unaffected herd. Real-time PCR (rtPCR) testing for Mycoplasma hyorhinis demonstrated consistent detection and high bacterial load in samples from affected herds (clinically affected animals and non-clinical pen-mates). Ct values in affected pigs were 18.9-25.3; values were 36.4-38.6 in unaffected pigs from unaffected herds. Additionally, M. hyorhinis was identified within inflamed palpebral conjunctivae by in situ hybridization. The association of rtPCR and in situ detection of M. hyorhinis, along with the lack of detection of other potential pathogens and noninfectious causes, suggests the involvement of M. hyorhinis in the etiology and pathogenesis of the reported swine conjunctivitis.

Tear Fluid Pharmacokinetics Following Oral Prednisone Administration in Dogs With and Without Conjunctivitis.

Purpose: To describe the pharmacokinetics (PK) of prednisone and prednisolone in tear fluid of dogs receiving oral prednisone at anti-inflammatory to immunosuppressive doses and to assess the impact of induced conjunctivitis on lacrimal drug levels. Methods: Six healthy Beagle dogs were administered 4 courses of prednisone at 0.5, 1.0, 2.0, and 4.0 mg/kg given orally once a day for 5 days. At steady state, topical histamine was applied to induce mild (1 mg/mL) or severe (375 mg/mL) conjunctivitis in 1 eye of each dog and tear samples were collected from both eyes at selected times. Prednisone and prednisolone were quantified in tears by liquid chromatography-mass spectrometry. Results: Lacrimal prednisone and prednisolone concentrations ranged from 2 to 523 ng/mL and 5 to 191 ng/mL, respectively. Drug concentrations were overall greater in dogs receiving higher doses of prednisone, but were not correlated with tear flow rate. Eyes with conjunctivitis often had larger amounts of prednisone and prednisolone in tear fluid compared to control eyes (up to +64%), but differences were not statistically significant. Significantly greater, but clinically insignificant, levels of prednisolone were found in eyes with severe versus mild conjunctivitis for oral prednisone doses ≥1.0 mg/kg. Conclusions: Disruption of the blood-tear barrier with conjunctivitis did not significantly affect drug levels in tears. Based on drug PK in tears, oral prednisone is likely safe for the management of reflex uveitis and ocular surface diseases. However, further prospective trials using systemic corticotherapy in diseased animals are warranted to confirm findings from this preclinical study.