# Eye Inoculation Technique: Aseptic Eye Swab Guide Eye inoculation, in the diagnostic sense, means introducing a swab or scraping into the conjunctival sac or onto the corneal surface to capture the microorganisms living or infecting there, then transferring that material to a culture medium, a slide, or a transport tube. The technique is simple in concept and unforgiving in execution. One brush against the eyelid skin, one swab used for both a stain and a culture plate, or one sample collected after fluorescein dye has touched the eye can turn a diagnostic result into a misleading one. By the end of this guide you will be able to restrain a dog, cat, horse, or cow for ocular sampling, collect a conjunctival swab from the lower fornix without contaminating it, decide when corneal sampling is appropriate and when it is not, split samples correctly between cytology and culture, and interpret the result against the normal ocular surface flora that every eye carries. You will also know the transport window and the specific mistakes that produce false negatives and false positives. **This article is educational and is not a substitute for veterinary diagnosis or treatment.** ## What You Need on Hand Before You Start Gather everything before you touch the animal. Once the head is restrained and the eye is open, you should not be searching a drawer. - Sterile swabs with transport medium. For culture, use a swab that comes with Amies or Stuart transport medium. Plain dry swabs are acceptable for cytology only. - Sterile saline, preservative free. Do not use multi-dose saline containing benzalkonium chloride for moistening a culture swab. - Glass slides and a pencil for labeling. - A topical anesthetic, used only if corneal scraping is planned. Note that anesthetics can suppress culture growth, so the culture swab is taken before the anesthetic is applied. - Fluorescein strips or solution, used only after all culture and cytology samples are collected. - A good light source, ideally a headlamp or a transilluminator, and a magnifying loupe. - A muzzle or a gauze strip for dogs, a towel for cats, a halter or stocks for horses and cattle. - Gloves, and a sharps container if a scalpel blade will be used for corneal scraping. The single most common reason a veterinary eye culture fails is not a fastidious organism. It is a sample that was collected from the wrong surface, at the wrong time, or transported too slowly. ## Why Sampling Site Determines the Result The ocular surface is not one uniform environment. The conjunctiva, the cornea, the eyelid margin, and the tear film each carry different microbial populations, and each is sampled for different reasons. The conjunctival sac, and specifically the lower conjunctival fornix, is a fold of tissue where tears pool and where commensal bacteria sit in relatively stable numbers. Sampling here gives you a representative picture of the ocular surface flora and of superficial conjunctival infection. It is the correct site for most routine eye inoculation procedures. The cornea is normally sterile. When bacteria or fungi are recovered from the corneal surface or from a corneal ulcer, that growth is more likely to represent true infection than when the same organism is grown from the conjunctiva. This is why corneal sampling carries more diagnostic weight but is also harder to perform without causing harm. A study of canine corneal ulcers from a specialized ophthalmology clinic in Berlin found positive bacterial growth in 79.5% of 112 samples, yielding 107 isolates [1]. Gram-positive organisms made up 72.2% of isolates, led by Staphylococcus pseudintermedius at 27.8% and beta-hemolytic Streptococcus at 19.4% [1]. That study also found multidrug resistance in 27% of isolates, which is the practical argument for culturing rather than guessing [1]. In a separate review of 3,470 corneal ulcer scrapings from a national ophthalmology institute in Peru, 88.1% of samples were positive, with coagulase-negative Staphylococci the most frequent bacteria at 69.8% and Staphylococcus epidermidis the single most isolated organism at 51.9%, followed by Pseudomonas aeruginosa and Staphylococcus aureus at 8.5% each [2]. Both datasets describe corneal disease, and both show why site and technique matter: a conjunctival swab would have produced a different, less specific answer. ## Restraint That Protects the Sample and the Animal Restraint for ocular sampling has one goal beyond safety. It must hold the head still enough that the swab tip never touches skin, lashes, or the examiner's glove. For dogs, place the animal in a sitting or sternal position on a non-slip surface. An assistant stands behind the head and cups the muzzle from above with one hand, using the other forearm to stabilize the neck against the assistant's body. A gauze muzzle can be applied if needed, but it must not obstruct access to the eye. For brachycephalic breeds, expect a wider palpebral fissure and shallower orbit, which paradoxically makes the fornix easier to reach but the cornea easier to traumatize. For cats, a towel wrap is usually more effective than manual scruffing. Wrap the body so all four limbs are contained, then have the assistant hold the head from behind with the thumb and forefinger on the zygomatic arches, tilting the nose slightly upward. Never apply pressure to the globe itself. For horses, a halter and a twitch or a lip chain provide control, but the examiner should stand at the side of the head, not directly in front. The horse's globe is large and the lower fornix is deep, so a longer swab is often needed. A nose twitch is applied by a second handler, and the head is steadied against the handler's shoulder. For cattle, a head gate or halter with the head restrained against a solid surface works well. Cattle have a prominent orbital rim and a shallow conjunctival sac compared with horses, so the swab does not need to travel far. In all species, the assistant should hold the eyelids apart using the eyelid margins only, never pressing on the globe. If the animal is fractious or the eye is painful, chemical restraint is appropriate and should be planned before the procedure, not improvised during it. ## Step-by-Step Conjunctival Swab Technique This is the core eye inoculation procedure. Follow the order exactly, because the order protects the culture result. ### Step 1: Prepare and label Label the culture swab tube and the cytology slide before sampling. Include the eye (OD for right, OS for left), the date, and the site. If both eyes are sampled, use separate swabs and separate slides for each eye. Never sample the unaffected eye with the same swab used on the affected eye. ### Step 2: Moisten the culture swab if required If the transport system requires it, moisten the swab tip with sterile preservative-free saline. Do not use tap water, do not use multi-dose saline with preservatives, and do not dip the swab into the transport medium before sampling. ### Step 3: Expose the lower conjunctival fornix Have the assistant retract the lower eyelid gently downward and slightly outward. This everts the lower lid and opens the inferior fornix, the groove between the eyelid and the globe. The fornix is the target. The cornea is not. ### Step 4: Roll the swab in the fornix Insert the swab tip into the lower fornix and roll it gently along the conjunctival surface from medial to lateral, then back. Use a rolling motion, not a scrubbing motion. Contact the conjunctiva for two to three seconds. Do not touch the eyelid skin, the eyelashes, the meibomian gland openings at the lid margin, or the cornea. ### Step 5: Withdraw without contact Withdraw the swab along the same path it entered. The tip must not drag across the lid margin on the way out. If the tip contacts skin, discard the swab and start again with a new one. ### Step 6: Place the culture swab in transport medium Insert the swab into its transport tube immediately and break or cut the shaft at the marked line. Cap the tube. Do not leave the swab sitting on the table. ### Step 7: Collect the cytology sample with a separate swab Take a fresh sterile swab and repeat the fornix sampling. Roll the tip gently onto a clean glass slide in a single smooth pass, creating a thin, even film. Do not rub back and forth on the slide, which crushes cells. Allow the slide to air dry, then fix it if your [laboratory protocol](/knowledge/diagnostics/molecular/laboratory-protocol-sections-version-control-deviations) requires it. ### Step 8: Stain or apply fluorescein only after all samples are collected If fluorescein is needed to assess corneal integrity, apply it now, after the culture and cytology swabs are safely in their containers. If a topical anesthetic is needed for a subsequent Schirmer tear test or for corneal scraping, apply it now as well. The order is not negotiable. Fluorescein and topical anesthetics can inhibit bacterial growth in culture, so any sample collected after their application is compromised [1]. The same principle applies to fluorescein, which is a dye that can interfere with both culture and cytology interpretation. ## Corneal Sampling: When and How Corneal sampling is indicated when there is a corneal ulcer, an infiltrate, a stromal abscess, or a non-healing corneal lesion where the clinician needs to know the causative organism. It is not a routine procedure and it carries a risk of perforation if the cornea is already thin. ### Step 1: Confirm the indication and assess depth Examine the cornea under magnification. A deep ulcer with a descemetocele is a contraindication to aggressive scraping. If the cornea is at risk of perforation, discuss with the owner whether a less invasive alternative such as tear-based sequencing is appropriate. ### Step 2: Apply topical anesthetic Instill a topical anesthetic such as proparacaine. Wait for full effect, usually under a minute. Confirm the animal no longer responds to a gentle touch on the cornea. ### Step 3: Collect the culture sample first Use a sterile swab or a sterile spatula. For a swab, roll the tip gently across the ulcer bed and the leading edge of the lesion. For a scraping, use a sterile scalpel blade or a Kimura spatula held nearly parallel to the corneal surface and scrape the base and leading edge of the ulcer with a single gentle stroke. Do not scrape the surrounding normal cornea. ### Step 4: Inoculate culture media directly if possible If you are working in a clinic with in-house culture capability, inoculate the plate directly at the bedside. If not, place the swab or scraping material into transport medium and send it to a reference laboratory. ### Step 5: Collect the cytology sample Use a separate sterile instrument to collect a second sample for cytology. Smear it thinly on a slide. For corneal samples, the smear should be made with a gentle circular motion, not a hard scrape, to preserve cell morphology. ### Step 6: Apply fluorescein last After all samples are collected, apply fluorescein to document the ulcer size and shape. A prospective study comparing corneal scraping with corneal biopsy in non-healing keratitis found a culture positivity rate of 59.09% for scraping and 77.27% for biopsy in bacterial keratitis, and a significantly better culture positivity rate for biopsy in fungal keratitis [3]. That study was in humans, but the principle applies across species: when the lesion is deep or the animal has already received antimicrobials, a superficial swab may not reach the organism. A separate human study evaluated pediatric blood culture bottles as a culture method for corneal scrapings and found overall culture positivity of 49.3%, with Pseudomonas aeruginosa the most frequently isolated pathogen at 22.9% [4]. That study also used MALDI-TOF mass spectrometry for identification, which is increasingly available in veterinary reference laboratories. ## Sample Handling, Transport, and Timing The sample is only as good as its handling after collection. - Culture swabs go into Amies or Stuart transport medium immediately. Do not leave them dry. - Deliver culture swabs to the laboratory within 24 hours. If the laboratory is closed, refrigerate the transport tube at 4 degrees Celsius, do not freeze it. - Cytology slides are air dried and delivered with the culture swab. Do not refrigerate slides that have already been fixed. - If a fungal culture is suspected, note it on the submission form. Fungal cultures require Sabouraud dextrose agar and a longer incubation period than routine bacterial cultures. - If a viral or molecular test is planned, use a separate swab in viral transport medium or a dry swab according to the laboratory's instructions. Do not put a viral swab into bacterial transport medium. The transport window matters because fastidious organisms such as Moraxella species and some Streptococcus species can die off quickly in a dry or warm environment. A swab that sits in a hot car for three hours may grow only the hardiest contaminants. ## The Normal Flora Problem Every eye carries bacteria. The conjunctival sac of a healthy animal is not sterile, and the organisms that live there are called commensals. This is the single biggest interpretive trap in ocular microbiology. A study of the ocular surface microbiome in humans found that Corynebacterium, Staphylococcus, Cutibacterium, and Streptococcus were the most abundant genera, with Actinobacteria, Firmicutes, and Proteobacteria as the dominant phyla [5]. A study of healthy donkeys found that about 82% of conjunctival swabs grew bacteria, with Pantoea agglomerans the most prevalent species followed by Moraxella lacunata [6]. That study also noted that the commensal flora of donkeys differed from that of horses despite geographic proximity, which is a reminder that species matters [6]. A study of cats and dogs with conjunctivitis in Turkey found that only 33.9% of 59 conjunctival swab samples were positive for [bacterial culture](/blog/guides/bacterial-culture), with Staphylococcus epidermidis, Corynebacterium mucifaciens, Psychrobacter species, and Streptococcus lutetiensis the most frequent isolates [7]. That low positivity rate is itself informative. Many cases of conjunctivitis are not primarily bacterial, and a positive culture does not automatically mean the isolated organism is the cause. The practical rule is this: a conjunctival swab result must be interpreted alongside cytology. If cytology shows intracellular bacteria, degenerate neutrophils, or a monomorphic population of organisms, the culture result is more likely to be clinically meaningful. If cytology shows a mixed population of organisms with no inflammatory cells, the culture is more likely to represent normal flora. For corneal samples, the interpretation is different. The cornea is normally sterile, so any growth from a properly collected corneal sample is more likely to be significant. A study of infectious bovine keratoconjunctivitis found Moraxella bovoculi cultured from 25.88% of IBK eyes versus 4.40% of normal eyes, and [Moraxella bovis](/knowledge/bacteria/livestock-bacteria/moraxella-bovis) from 3.07% of IBK eyes versus 0.63% of normal eyes [8]. That difference in isolation rate between diseased and normal eyes is what gives a culture result its diagnostic weight. ## Species-Specific Sampling Sites and Expected Isolates The table below summarizes the sampling site, the primary indication, and the common isolates for dogs, cats, horses, and cattle. It is a guide to interpretation, not a substitute for culture and susceptibility testing. | Species | Primary sampling site | Main indication | Common isolates | |--|--|--|--| | Dog | Lower conjunctival fornix, corneal ulcer bed | Conjunctivitis, corneal ulcer, keratoconjunctivitis sicca workup | Staphylococcus pseudintermedius, beta-hemolytic Streptococcus, Staphylococcus epidermidis, Pseudomonas aeruginosa [1][2] | | Cat | Lower conjunctival fornix | Conjunctivitis, upper respiratory complex, FeLV proviral DNA testing | Staphylococcus epidermidis, Corynebacterium mucifaciens, Streptococcus lutetiensis, Psychrobacter species [7] | | Horse | Lower conjunctival fornix, corneal ulcer bed | Corneal ulcer, keratitis, fungal keratitis workup | Staphylococcus species, Streptococcus species, Pseudomonas species, fungal organisms including Aspergillus and Fusarium | | Cattle | Lower conjunctival fornix, corneal ulcer bed | Infectious bovine keratoconjunctivitis, corneal ulcer | Moraxella bovoculi, Moraxella bovis, Corynebacterium species [8] | For horses, fungal keratitis is a particular concern, and a study of human fungal keratitis found that Fusarium species was the most common fungus in corneal ulcers, with white cotton-like colonies on blood and chocolate agar and transparent septate hyphae on microscopy [9][2]. In horses, Aspergillus and Fusarium are both reported, and a fungal culture should be requested whenever a corneal ulcer fails to respond to antibacterial therapy. ## Workflow Decision Path The flowchart below shows the decision path from presentation to sample submission. ```mermaid flowchart TD A[Animal presents with ocular signs] --> B{Is the cornea involved} B -->|No| C[Collect conjunctival swab from lower fornix] B -->|Yes| D[Assess corneal depth and integrity] D --> E{Is the cornea at risk of perforation} E -->|Yes| F[Consider tear based or less invasive testing] E -->|No| G[Apply topical anesthetic] G --> H[Collect corneal culture sample first] H --> I[Collect corneal cytology sample separately] I --> J[Apply fluorescein last] C --> K[Split culture and cytology swabs] K --> L[Place culture swab in transport medium] L --> M[Deliver to laboratory within 24 hours] J --> M F --> M ``` ## Common Errors and How to Fix Them ### Error: The swab touched the eyelid skin This is the most frequent contamination error. The fix is to discard the swab and start again. Do not try to clean the swab or use it anyway. Skin flora such as Staphylococcus epidermidis and Corynebacterium species will overgrow the ocular organisms and make the culture uninterpretable. ### Error: The same swab was used for cytology and culture This produces two problems. The cytology slide is contaminated with transport medium, and the culture is contaminated with cells and debris from the slide. Use two separate swabs. ### Error: Fluorescein was applied before the culture swab Fluorescein can inhibit bacterial growth. If the eye has already been stained, the culture result is unreliable. The fix is to wait until the dye has cleared, which may take hours, or to accept that the culture result may be a false negative and repeat sampling at a later visit. ### Error: The sample was left at room temperature overnight Fastidious organisms die. The fix is to refrigerate the transport tube at 4 degrees Celsius if delivery is delayed, and to deliver within 24 hours. ### Error: The culture grew a mixed population of skin flora This usually means the swab touched the lid margin or the skin. The fix is to repeat the sample with better restraint and a more careful approach to the fornix. ### Error: The culture was negative but the eye is clearly infected This can happen if the animal has already received antibiotics, if the sample was collected after fluorescein, if the organism is fastidious or fungal, or if the sample was transported poorly. The fix is to correlate with cytology, consider a fungal culture, and repeat sampling if clinically indicated. A study of conjunctival swabs for Leishmania DNA in dogs found that PCR positivity was significantly higher in dogs without periocular injury than in dogs with periocular injury, and that the technique was indicated to complement diagnosis especially in dogs without periocular injury [10]. That finding is a reminder that the presence or absence of visible ocular lesions does not reliably predict whether a conjunctival swab will yield a diagnostic result. ## Cytology: The Partner Test That Makes Culture Interpretable Cytology and culture answer different questions. Culture tells you what grew. Cytology tells you what was there and whether the host was responding to it. For conjunctival cytology, look for: - Neutrophils. Their presence suggests acute inflammation. - Intracellular bacteria. This is strong evidence that the bacteria are causing disease, not just colonizing. - A monomorphic population of organisms. This supports a true infection. - A mixed population with no inflammatory cells. This supports normal flora. - Fungal elements such as hyphae or yeast. This supports fungal infection and should prompt a fungal culture. For corneal cytology, the same principles apply, but the threshold for significance is lower because the cornea is normally sterile. A study of corneal scrapings found that the sensitivity and specificity of Gram stain were 55.56% and 92.31%, and of potassium hydroxide stain were 50% and 94.4% [3]. Those numbers mean that a positive stain is fairly reliable, but a negative stain does not rule out infection. Culture remains the confirmatory test. A study of tear-based [nanopore sequencing](/blog/guides/nanopore-sequencing) found that bacterial DNA was identified in 8 of 10 samples, and that sequencing accurately identified the causative bacteria in all four samples that grew on culture and detected pathogens in two of four ulcers that did not grow on culture [11]. That study also identified commensal bacteria in four of nine contralateral tear samples, which reinforces the normal flora problem [11]. Molecular methods are becoming more available, but they do not eliminate the need for careful sampling and interpretation. ## Special Considerations for Molecular Testing Conjunctival swabs are increasingly used for PCR and sequencing, not just culture. A study of FeLV proviral DNA detection in cats found that conjunctival swabs had a sensitivity of 95.3% and a specificity of 100% compared with blood samples, with a kappa value of 0.956 [12]. That makes conjunctival swabs a reliable alternative to venipuncture for FeLV testing in cats. A study of Coccidioides PCR in dogs with pulmonary coccidioidomycosis found that none of 72 conjunctival, nasal, or oropharyngeal swabs positively detected Coccidioides DNA, even though 46% of dogs had positive IgM and 71% had positive IgG serology [13]. That is a useful negative result. It shows that a conjunctival swab is not a reliable sample for every organism, and that the choice of sample site must match the suspected pathogen. For molecular testing, use a separate swab in the transport medium specified by the laboratory. Do not assume that a bacterial transport medium is suitable for viral or fungal PCR. ## Interpreting the Result in Context A culture result is never interpreted in isolation. The clinical signs, the cytology, the species, the site, and the history all shape the interpretation. A positive culture from a corneal ulcer in a dog with a deep stromal lesion and cytology showing intracellular bacteria is strong evidence of bacterial keratitis. A positive culture from a conjunctival swab in a cat with mild conjunctivitis and cytology showing no inflammation is more likely to represent normal flora. A negative culture from a corneal ulcer in a horse that has been treated with topical antibiotics for two weeks is not reassuring. It may mean the organism is suppressed but not eliminated, or that the sample did not reach the organism. A study of infectious corneal ulcer outcomes in a real-world cohort found that microbiologic confirmation was obtained in 49.0% of episodes, with bacterial keratitis predominating at 76.2% of confirmed cases [14]. That means half of clinically diagnosed corneal ulcers did not yield a positive culture. Poor sampling technique, prior antimicrobial therapy, and fastidious organisms all contribute to that figure. ## Clinical Relevance, Limitations and Common Mistakes Eye inoculation is a high-value, low-cost diagnostic procedure when it is done correctly. It distinguishes bacterial from fungal infection, guides antimicrobial selection, and provides epidemiological information that supports responsible antibiotic use. The Berlin study found multidrug resistance in 27% of canine corneal ulcer isolates, which is a direct argument for culture before treatment [1]. The limitations are real. Normal conjunctival flora complicates interpretation of conjunctival swabs. Corneal sampling carries a risk of perforation in deep ulcers. Culture sensitivity is imperfect, and a negative result does not rule out infection. Molecular methods are increasingly available but are not universally accessible and do not replace cytology. The most common mistakes are contamination from skin contact, using one swab for both cytology and culture, sampling after fluorescein or anesthetic application, and delayed transport. Each of these is preventable with a disciplined routine. Individual cases require veterinary judgment. The technique described here is a framework, not a protocol that can be applied identically to every patient. ## Frequently Asked Questions ### What is eye inoculation in veterinary practice? Eye inoculation is the process of introducing a swab or scraping instrument into the conjunctival sac or onto the corneal surface to collect microorganisms for culture, cytology, or molecular testing. It is a diagnostic procedure, not a treatment. ### Which eye surface should I sample first, the conjunctiva or the cornea? Sample the lower conjunctival fornix first if both sites are being sampled, because the conjunctival sample is less invasive and less likely to be contaminated by corneal manipulation. If only the cornea is being sampled, collect the corneal culture sample before applying fluorescein or collecting cytology. ### Can I use the same swab for cytology and culture? No. Use separate swabs for cytology and culture. A single swab cannot serve both purposes without compromising one or both results. ### Why does fluorescein interfere with culture? Fluorescein and topical anesthetics can inhibit bacterial growth in culture. Collect all culture and cytology samples before applying either agent to the eye. ### How long can a conjunctival swab sit before it is processed? Deliver the culture swab to the laboratory within 24 hours. If delivery is delayed, refrigerate the transport tube at 4 degrees Celsius. Do not freeze it and do not leave it at room temperature. ### What bacteria are normally found on a healthy eye? Normal conjunctival flora varies by species but commonly includes Staphylococcus, Streptococcus, Corynebacterium, and Moraxella species. A positive conjunctival culture must be interpreted alongside cytology to distinguish normal flora from infection. ### When should I request a fungal culture? Request a fungal culture when the corneal ulcer is deep, when it fails to respond to antibacterial therapy, when cytology shows hyphae or yeast, or when the species and history suggest fungal keratitis, such as in horses with a history of ocular trauma. ### Can a conjunctival swab be used for PCR testing? Yes, conjunctival swabs are used for PCR testing for several pathogens, including FeLV proviral DNA in cats and Leishmania DNA in dogs. Use the transport medium specified by the laboratory for the specific test being requested. ## Related Articles - [Mastering Aseptic Technique: A Step-by-Step Guide for Microbiologists](/blog/careers/mastering-aseptic-technique-a-step-by-step-guide-for-microbiologists) - [Aseptic Technique in Microbiology: Essential Steps and Common Mistakes](/knowledge/diagnostics/microbiology/aseptic-technique-microbiology-steps-mistakes) - [Aseptic Technique in Microbiology Lab: Essential Steps and Best Practices](/knowledge/diagnostics/microbiology/aseptic-technique-microbiology-lab-steps) - [How to Showcase Cell Culture and Aseptic Technique Skills on Your Resume](/blog/careers/how-to-showcase-cell-culture-and-aseptic-technique-skills-on-your-resume) - [How to Sterilize Inoculation Loops and Needles: Methods and Best Practices](/knowledge/diagnostics/microbiology/sterilize-inoculation-loops-needles) - [Routes of Inoculation in Embryonated Chicken Eggs: A Comprehensive Technical Reference](/knowledge/diagnostics/microbiology/routes-of-inoculation-in-embryonated-chicken-eggs) - [Inoculation Definition: Meaning in Microbiology](/knowledge/diagnostics/microbiology/inoculation-definition-meaning-in-microbiology) - [Optic Nerve and Chiasm: Anatomy and Pathway](/knowledge/veterinary-medicine/veterinary-anatomy-physiology/optic-nerve-and-chiasm-anatomy-and-pathway) ## Sources 1. [Patterns of Bacterial Infection and Antibiotic Resistance in Canine Corneal Ulcers: A Retrospective Analysis (Berlin, Germany, 2021-2024).](https://pubmed.ncbi.nlm.nih.gov/42627045/) 2. [Microbiological profile of bacterial and fungal corneal ulcers at a national institute of ophthalmology in Perú.](https://pubmed.ncbi.nlm.nih.gov/40157497/) 3. [Corneal biopsy as a primary diagnostic tool in microbial keratitis patients on poly-antimicrobials.](https://pubmed.ncbi.nlm.nih.gov/42376299/) 4. [Diagnostic value of paediatric blood culture bottle allied to MALDI-TOF mass spectrometry in the aetiological assessment of microbial keratitis.](https://pubmed.ncbi.nlm.nih.gov/41793812/) 5. [Alterations of ocular surface microbiome in glaucoma and its association with dry eye.](https://pubmed.ncbi.nlm.nih.gov/40359128/) 6. [Aerobic Commensal Conjunctival Microflora in Healthy Donkeys.](https://pubmed.ncbi.nlm.nih.gov/35327153/) 7. [Microbiological investigation of conjunctivitis in cats and dogs from Kars, Türkiye (2024-2025): culture- and MALDI-TOF MS-based identification and antimicrobial susceptibility testing of bacterial isolates.](https://pubmed.ncbi.nlm.nih.gov/42750033/) 8. [Alterations to the bovine bacterial ocular surface microbiome in the context of infectious bovine keratoconjunctivitis.](https://pubmed.ncbi.nlm.nih.gov/37996960/) 9. [Fusarium keratitis in an older adult without exogenous or traumatic risk factors: A case report on intrinsic ocular surface predisposition.](https://pubmed.ncbi.nlm.nih.gov/42389003/) 10. [Polymerase chain reaction using conjunctival swab samples for detecting Leishmania DNA in dogs.](https://pubmed.ncbi.nlm.nih.gov/34259743/) 11. [A Tear-Based Approach for Rapid Identification of Bacterial Pathogens in Corneal Ulcers Using Nanopore Sequencing.](https://pubmed.ncbi.nlm.nih.gov/40244576/) 12. [PCR testing of conjunctival swabs to detect feline leukaemia virus in domestic cats in Thailand.](https://pubmed.ncbi.nlm.nih.gov/40255021/) 13. [Polymerase chain reaction may not be useful to detect Coccidioides spp DNA in oropharyngeal, nasal, or conjunctival swab samples in dogs with newly diagnosed pulmonary coccidioidomycosis.](https://pubmed.ncbi.nlm.nih.gov/41719699/) 14. [Predictors of Infectious Corneal Ulcer Outcomes in a Real-World Cohort: Clinical Risk Factors, Microbiology, and Antimicrobial Resistance.](https://pubmed.ncbi.nlm.nih.gov/42403184/)