Bilateral nodular lymphocytic conjunctivitis in a horse

A Russian jumper horse presented because of an ocular perilimbal conjunctival mass and, on clinical examination, two bilateral conjunctival masses were found, of different size and conformation. Attempts at complete excision of the left eye mass and excisional biopsy of the right eye mass were performed. The left eye mass recurred rapidly, but resolved completely after topical corticosteroid therapy. The two lesions had similar histopathologic features, characterized by focal, chronic, primarily lymphocytic conjunctivitis with follicular lymphoid hyperplasia. Special histopathologic staining techniques (Gomori methenamine silver and acid fast stains) and immunohistochemistry (for CD3, BLA36 and lysozyme) failed to reveal any etiologic agents and indicated an inflammatory lesion composed of a heterogeneous population of lymphocytes and macrophages (nodular lymphocytic conjunctivitis). The lesions were indistinguishable, clinically and behaviorally, from what has been reported as 'conjunctival pseudotumor' in the horse. Equine conjunctival pseudotumor/nodular lymphocytic conjunctivitis has been reported to be unilateral and have a good prognosis after partial or complete surgical excision. This is the first reported case of bilateral nodular lymphocytic conjunctivitis in a horse and for which surgical excision alone was not curative.     

Surgical correction of aberrant conjunctival overgrowth in a rabbit: a case report

A dwarf rabbit presented with unilateral aberrant conjunctival growth. Allgoewer’s U-suture therapy was initially used to correct the overgrowth. Centrifugal incisions extending up to the limbus were made on the hypertrophic conjunctiva. Transpalpebral limbal fixation was performed next. When the symptoms recurred 3 weeks later, a second operation was performed using the Lembert suture method instead. The overgrowing membrane was excised radically just posterior to the limbus. The conjunctiva was then sutured using the Lembert pattern. The rabbit recovered with no further complications.     

Equine developmental dental disorders

The true prevalence of developmental dental disorders in horses is unknown, but from a clinical perspective, dental dysplasia of varying degrees of severity appears to be far more common than developmental abnormalities of tooth numbers. The latter includes the presence of increased numbers of teeth (supernumerary teeth), which in turn appears more prevalent than reduced numbers of teeth (hypodontia or anodontia). This clinical commentary briefly reviews all three types of developmental dental disorders from a clinical viewpoint.     

Aberrant conjunctival stricture and overgrowth in the rabbit

Six dwarf rabbits with unilateral (n = 2) and bilateral (n = 4) aberrant conjunctival growth underwent surgical correction. The applied technique involved centrifugal incisions of the overgrowing conjunctiva to the limbus and a transpalpebral fixation of the conjunctiva. In this way the conjunctival fornix was reconstructed. No relapses were noted within the observation period (5-72 months).     

Equine immune-mediated keratopathies

Equine immune mediated keratopathies are common in both Europe and the USA. This review article will compare the clinical differences in horses with this disease and also review the current theories on pathogenesis and treatment of equine IMMK.     

Equine post-breeding endometritis: A review

The deposition of semen, bacteria and debris in the uterus of the mare after breeding normally induces a self-limiting endometritis. The resultant fluid and inflammatory products are cleared by 48 hours post cover. Mares that are susceptible to persistent post-breeding endometritis (PPBEM) have impaired uterine defence and clearance mechanisms, making them unable to resolve this inflammation within the normal time. This persists beyond 48 hours post-breeding and causes persistent fluid accumulation within the uterus. Mares with PPBEM have an increased rate of embryonic loss and a lower overall pregnancy rate than those without the condition. To enhance conception rates, mares at high risk need optimal breeding management as well as early diagnosis, followed by the most appropriate treatment. This article reviews the pathogenesis, diagnosis and treatment of PPBEM and the management of affected mares.     

Radiographic Examination of the Equine Vertebral Column

A method is described for routine radiography of the horse's thoracolumbar (TL) spine from T2 to L3 in the standing position. Stocks were used for restraint, and the x-ray tube, which was mounted on an overhead gantry, was linked automatically to a cassette holder on the far side of the animal. A crosshatch grid with an ultra-fast system of screens and film was employed to provide adequate radiographic quality. An aluminum wedge filter (dodger) was used to help compensate for the marked variation in spine thickness. For radiography of the caudal lumbar spine and lumbosacral region, it was necessary to anesthetize the horse and make radiographs in the ventrodorsal position. Exposures of up to 150 kV and 400 mAs were required for heavy horses weighing up to 750 kg. Scatter radiation was kept to a minimum by using crossed high-ratio grids and by putting additional lead on the back of the cassette to prevent back scatter.     

Equine pectinate ligament descemetization is associated with age

Purpose

To evaluate the correlation between equine pectinate ligament descemetization and ocular disease.

Methods

The pathology database of the North Carolina State University Veterinary Medical Center was searched from 2010–2021 for all equine globes. Disease status was then assigned as affected by glaucoma, uveitis, or “other” based upon clinical records. The iridocorneal angles (ICA) of each globe were evaluated for the presence of pectinate ligament descemetization, the length of descemetization, as well as for the degree of angle collapse and the extent of cellular infiltrate or proteinaceous debris. One slide from each eye was evaluated by two separate, blinded investigators (HW & TS).

Results

A total of 66 eyes from 61 horses were identified, with a total of 124 sections of ICA of sufficient quality to review. 16 horses were affected by uveitis, 8 by glaucoma, 7 by both glaucoma and uveitis, and 30 horses by other ocular disease, most commonly ocular surface disease or neoplasia, which served as controls. Pectinate ligament descemetization was most prevalent in the control group compared to the glaucoma and uveitis groups. Pectinate ligament descemetization length was positively correlated with age, with an increase of 13.5 μm per year of age (p = .016). Infiltrate scores and angle closure scores were higher in both the glaucoma and uveitis group compared to the control group (p < .001).

Conclusions

Equine pectinate ligament descemetization appears to be correlated with increased age and should not be used as a histologic marker for the presence of glaucoma.     

应用B型超声波鉴别马胎儿性别

通过胎儿尾部和脐带之间的生殖器结节定位进行马性别诊断，雄性胎儿准确率97．8％（182／186），雌性胎儿99．4％（160／161）。胎儿性别测定的最适时间为妊娠后59d和68d之间。妊娠中期胎儿性别诊断也非常可靠。超声波性别鉴定准确率达100％。在雄性，从100d到220d妊娠常规获得阴茎或包皮的图像；在雌性，从118d到227d妊娠马观察到胎儿乳腺和乳头。在马繁殖上常规使用的5MHz线性传感器，大多数情况下一直可用到妊娠160d。当胎位太高或其大小超过超声设备监测范围时，须使用3．5MHz探头。若掌握好性别鉴定的最适时间和认识正确的解剖结构，两种方法都是非常精确的。     

Radiographic Features of the Normal Equine Thoracolumbar Spine

The normal radiographic anatomy of the equine thoracolumbar (TL) spine is described from birth to maturity. Closure of the vertebral epiphyses was found to take place from 30 to 38 months of age. In a series of 110 normal horses, there were few incidental radiologic abnormalities seen apart from changes associated with crowding and overriding of the dorsal spinous processes. Sixty-six percent of horses were free from any detectable radiologic lesion, and an additional 12 percent showed only impingement of the dorsal tips of one or more summits. The remainder (22 percent) exhibited some evidence of overriding of the dorsal spinous processes, but in only 3 percent were the changes pronounced. This reduction or obliteration of the normal interspinous spaces occurred chiefly in the midback from T13 to T18 and was associated with pressure points between adjacent spines with local periosteal reaction and focal areas of radiolucency. The tips of the processes sometimes overlapped one another and became misshapen, presumably as a result of continued pressure from the adjacent impinging spines.     

马属动物肠道微生物的研究进展

马属动物肠道中的微生物对其消化具有重要的作用,尤其是盲肠中的微生物,它的数量和种类影响机体对营养物质的消化利用,文中主要论述了马属动物肠道微生物在机体的定殖发展的过程以及各种微生物对机体的主要作用,并对粗饲料对肠道菌群的影响进行了综述。     

The conjunctival crypt of the equine third eyelid

The purpose of this study is to characterise the gross anatomy of a relatively large, cryptic structure within the bulbar conjunctival surface of the equine third eyelid that has commonly been observed by the authors during equine ophthalmic examinations. In this study, cadaveric eyes and adnexa were obtained from 13 Quarter Horses without history of ocular disease. The gross anatomy of the bulbar surface of the third eyelid was characterised by digital macrophotography and with an image capture system using an operating microscope. A well-defined cryptic structure was readily identified in the majority of eyes (17/26). The location of the crypt varied but was most commonly observed within the central aspect of the bulbar surface of the third eyelid, often in close proximity to prominent blood vessels oriented perpendicular to the leading edge of the third eyelid. A patch of lymphoid follicles was often observed surrounding the crypt. The rectangular shape and upward facing orientation of the crypt was akin to a shirt's breast pocket. Width and depth were variable but ranged between 1 and 8 mm in either dimension. Some crypts were complex, with multiple channels observed within the primary opening. In conclusion, this study confirms the presence of a well-organised mucosal crypt within the bulbar surface of the equine third eyelid capable of harbouring foreign material and ocular irritants. Additional anatomical characterisation of the macro-crypt by light microscopy, immunohistochemistry and electron microscopy is underway. Evaluation of this structure by equine practitioners and veterinary ophthalmologists should be performed during the routine ophthalmic examination to better understand its role in ocular disease.     

Extranodal conjunctival Hodgkin's-like lymphoma in a cat

A seven-year-old female spayed Domestic Short-haired cat was brought for examination following a four-month history of conjunctivitis in the right eye. The superior palpebral conjunctiva was diffusely swollen and firm, displacing the right globe ventrally and preventing full closure of the eyelids. The right popliteal lymph node was enlarged as were several other peripheral lymph nodes. An incisional biopsy of the conjunctival swelling revealed a lymphoid neoplasm, the cellular make up of which suggested features of feline Hodgkin's-like lymphoma. Although the neoplasm was poorly responsive to standard chemotherapeutic protocols for lymphoma, radiation therapy rapidly reduced its size. Three years following the initial diagnosis, there has been no recurrence of the conjunctival neoplasm. To the authors' knowledge, there are no previous reports of extranodal or adnexal (conjunctiva, eyelid, orbit) Hodgkin's-like lymphoma in the veterinary literature.     

马属动物毕氏肠微孢子虫研究进展

毕氏肠微孢子虫是一种引起人和动物腹泻的常见病原体,可通过食物和水源传播,具有重要的公共卫生意义。根据系统进化分析,已鉴定出近300个毕氏肠微孢子虫基因型,分为9个组群,组群1中的基因型大多数具有潜在人兽共患性;组群2~8中的基因型多数具有宿主特异性,部分也可感染人。研究表明,马属动物可感染37个毕氏肠微孢子虫基因型,具有一定人兽共患风险。论文就近年来感染马属动物的毕氏肠微孢子虫基因型、人兽共患风险、流行情况和致病性等进行综述。     

Comparative morphology of epicorneal conjunctival membranes in rabbits and human pterygium

A rarely described ocular lesion in the rabbit is presented following the observation of four cases. It is a membrane of conjunctival origin that advances progressively, without adhering, towards the center of the cornea. Clinically the lesion in rabbits looks like pterygium in man, but with several differences: in rabbits, the conjunctival fold is absolutely free and does not penetrate into the superficial corneal layers. It originates from all the limbal circumference in a symetric growth. The cornea itself remains unaltered. The fold consists of fibroblasts and collagen. The microscopic findings suggest the lesion is possibly of a collagenous dysplasia.