IMAGING FINDINGS IN PANCREATIC NEOPLASIA AND NODULAR HYPERPLASIA IN 19 CATS

Pancreatic neoplasia in cats is rare and associated with a poor prognosis, but pancreatic nodular hyperplasia is a common incidental finding. The purpose of this study was to describe radiographic and ultrasonographic findings in cats with pancreatic neoplasia or nodular hyperplasia. Fourteen cats (age 3-18 years) were diagnosed with malignant pancreatic tumors: carcinoma/adenocarcinoma (n = 11), lymphoma (n = 1), squamous cell carcinoma (n = 1), and lymphangiosarcoma (n = 1). The most common radiographic findings were an abdominal mass or mass effect (6/6) and lack of serosal margin detail (4/6). On ultrasound, the most common finding was a focal pancreatic mass or nodule, with a size range from 0.4 cm to more than 7.0 cm (8/14). Lymphadenopathy (7/14) and abdominal effusion (7/14) were frequently seen. Five cats (age 10-16 years) with adenomatous/nodular hyperplasia had an abdominal mass or mass effect as the most common radiographic finding (3/3). On ultrasound, all cats had multiple hypoechoic nodules between 0.3 and 1.0 cm associated with the pancreas. Other common findings were pancreatic thickening (2/5), lymphadenopathy (2/5), and abdominal effusion (2/5). The only imaging finding unique to malignant pancreatic tumors was the presence of a single pancreatic nodule or mass exceeding 2cm in at least one dimension (4/14). Although there was a tendency for neoplastic lesions to manifest as single larger lesions and for nodular hyperplasia to manifest as multiple smaller lesions, there was overlap of the imaging findings in both entities. Radiographs and ultrasound can complement but not replace cytology and histopathology in the diagnosis of feline pancreatic neoplasia.     

牛结节性皮肤病的诊断及防控

牛结节性皮肤病又称牛结节性皮炎、牛结节疹或牛疙瘩皮肤病。临床上以发热、皮肤出现水肿、消瘦、淋巴结肿大、局部溃疡、可形成坚硬的结节为主要特征,世界动物卫生组织将该病列为法定报告的动物疫病。该病潜伏期长,病毒流行传播快不易发现;发病急,是严重影响养牛业健康发展的疫病之一。加强生物安全的综合防控措施,强化动物检疫工作,可以最大限度地减少疫情的传播。牛结节性皮肤病的发生,早诊断、早处置,对控制疫情的蔓延极为重要。各地畜牧兽医部门应建立内部疫情通报制度,落实疫情报告责任,使疫情地区接壤的相关区域尽快建立免疫隔离区,防止疫病的蔓延和传播。     

牛结节性皮肤病的防控

牛结节性皮肤病是由牛结节性皮肤病病毒感染牛只导致的一种传染病,肉牛、亚洲水牛、奶牛易感。该病发病时以全身皮肤广泛性结节为特征,因此又叫牛疙瘩皮肤病,除皮肤病变外还可能有发热,体表淋巴结肿大,口、鼻和眼部溃疡,鼻和眼部伴有分泌物,四肢及腹部、会阴等部位水肿等临床表现,死亡率低,但发病率高,传染性强,严重影响牛的生长发育和生产。2019年8月我国新疆伊利首次报道了该病,随后在福建、江西、广东等地发现了该病的流行。该病通过临床症状和流行病学调查可做出初步诊断,确诊需要通过实验室诊断。我国对该病的防控主要采取免疫、隔离、扑杀、消毒等综合性的防控措施。     

Cultivation and characterisation of primary and subcultured equine keratinocytes

We describe the establishment and characterisation of equine keratinocyte cultures with maintenance of a high proliferative capacity up to the second passage. Improved attachment and growth were obtained by seeding primary cells on equine feeder layers. Subcultured keratinocytes showed optimal growth when seeded on collagen type I. The proliferation rate of cells on this substrate exceeded that seen for cells seeded on equine feeder layers. By immunohistochemistry, epithelial origin and state of differentiation of the equine keratinocytes were determined. They expressed keratin and desmoplakin I/II, but lacked keratin 10. Electron microscopy revealed typical features of cultured keratinocytes. Purity of keratinocyte cultures was determined by vimentin staining. This is the first report on the establishment of equine keratinocytes derived from lip epithelium. It forms the basis to study equine keratinocyte biology and the pathogenesis of epidermal diseases. Since wound healing represents a severe problem in equine dermatology, our data may be essential for the establishment of new and improved therapy.     

ULTRASONOGRAPHIC FEATURES OF CANINE HEPATIC NODULAR HYPERPLASIA

Hepatic nodular hyperplasia is a benign, usually clinically inapparent, proliferative lesion commonly found at necropsy in older dogs. Three examples of hepatic nodular hyperplasia are described in dogs with clinical signs compatible with hepatic disease in which ultrasonography revealed a variety of echotextural changes in the liver similar to those reported in primary or secondary hepatic neoplasia. In subsequent in vitro ultrasonographic studies of hepatic nodular hyperplasia lesions detected at necropsy in dogs without clinical signs of hepatic disease, only subtle echotextural changes were seen. Hence, hepatic nodular hyperplasia may be inapparent in vivo in many dogs. Hepatic nodular hyperplasia is a potentially confusing sporadic finding which must be considered by ultrasonographers examining dogs with clinical signs of hepatic disease. The diagnosis of hepatic neoplasia should not be made on the basis of ultrasonographic findings alone.     

Multinodular pulmonary fibrosis in five horses

CASE DESCRIPTION: 5 horses were evaluated because of decreased appetite, weight loss, fever, cough, tachypnea, and respiratory distress. CLINICAL FINDINGS: Tachycardia, tachypnea, increased respiratory effort, lethargy, fever, poor body condition, and nasal discharge were detected in various combinations on initial physical examination. Evaluation of the lower portion of the respiratory tract via radiography and ultrasonography revealed a severe nodular interstitial pattern. Histologic examination of lung tissue revealed interstitial expansion of alveolar parenchyma with collagen, intraluminal accumulation of neutrophils and macrophages within the alveoli, and occasional intranuclear inclusion bodies within alveolar macrophages. Equine herpesvirus type 5 was detected in samples of lung tissue, bronchoalveolar lavage fluid, or both via polymerase chain reaction assay in all cases. A diagnosis of equine multinodular pulmonary fibrosis (EMPF) was established. TREATMENT AND OUTCOME: Horses were provided supportive treatment and were administered a variety of medications including corticosteroids and acyclovir. Two horses survived and returned to their previous level of activity. Three horses were euthanized because of either deterioration of clinical condition (n=2) or failure to improve within 4 weeks of initiation of treatment (1). CLINICAL RELEVANCE: EMPF should be considered as a differential diagnosis for adult horses with interstitial pneumonia and should be suspected on the basis of characteristic radiographic, ultrasonographic, and histopathologic findings. Equine herpesvirus type 5 is found in association with EMPF; although the exact pathogenic role this virus plays in EMPF is unknown, equine herpesvirus type 5 may be an etiologic agent or cofactor in the development of EMPF.     

ULTRASONOGRAPHIC IDENTIFICATION AND CHARACTERIZATION OF SPLENIC NODULAR LIPOMATOSIS OR MYELOLIPOMAS IN CHEETAHS (ACINONYX JUBATUS)

A total of 44 live cheetahs were examined sonographically between 1989 and 1994. Seventeen of these animals originated from 4 European facilities, the other 27 cheetahs were examined in 3 facilities in Namibia. Evaluation of the cheetahs included a clinical examination, abdominal ultrasound, and complete blood work. Splenic myelolipomas were diagnosed sonographically in 11 cheetahs. In 7 cheetahs the diagnosis was confirmed at necropsy. Nine of the 14 cheetahs in Europe had myelolipomas in the spleen, while in the African cheetahs there were only 2 animals with myelolipomas. Histologically these lesions were characterized by fatty nodules. A more fitting term of Nodular Lipomatosis of the spleen is therefore suggested. All cheetahs with nodular lipomatosis of the spleen, had concurrent chronic diseases at necropsy. An indicator function of splenic nodular lipomatosis for chronic disease and/or stress is possible.     

The Effects of Pentoxifylline on Equine Platelet Aggregation

Background: Pentoxifylline (PTX) possesses a number of vasomotor, immunomodulatory, and hemorheologic properties. Based upon the hypothesis that equine laminitis and navicular disease result from microthrombosis, the inhibitory effects of PTX on inflammatory cytokines, and its inhibitory effects on human platelet aggregation, PTX has been widely used to treat equine endotoxemia, navicular disease, and laminitis. Despite this, the effects of PTX on equine platelet aggregation have not been investigated previously. Hypothesis: PTX decreases platelet aggregation in equine whole blood at concentrations approximating those achieved in horses given clinically relevant doses of PTX. Animals: Seven healthy adult horses from a research herd. Methods: Whole blood impedance aggregometry using whole equine blood incubated with varying concentrations of PTX. Adenosine diphosphate (ADP) and collagen were used to initiate aggregation. Results: The onset time of collagen‐induced equine platelet aggregation was significantly shortened by PTX. The maximum slope of resistance change (dR/dt) and total resistance change of collagen‐induced platelet aggregation were unaffected by PTX. No effects of PTX on ADP‐induced onset time of aggregation, dR/dt, or total resistance change were observed. Conclusions and Clinical Importance: Our hypothesis is not supported by the results. PTX hastens the onset of collagen‐induced platelet aggregation in equine whole blood, but has no effect on the rate of collagen‐induced aggregation. PTX does not affect ADP‐dependent equine platelet aggregation. Given these findings, PTX may not be a reasonable therapeutic option to decrease platelet aggregation in horses.     

Generalized nodular dermatofibrosis in the absence of renal neoplasia in an Australian Cattle Dog

A 13-year-old, spayed, female Australian Cattle Dog had at least a 10-year history of numerous subcutaneous nodules for which fine-needle aspiration and cytologic evaluation were nondiagnostic. Abdominal ultrasound 3.5 months before necropsy detected a small left kidney but no cysts or neoplasms. At gross necropsy, innumerable, firm, round to oval, white, 0.25 to 2 cm masses were detected throughout the subcutaneous tissues of the axial and appendicular skeleton, epimysium of numerous muscles, and parietal peritoneum of the lateral abdominal body wall. The left kidney was approximately half the size of the right, and there was severe bilateral renal medullary (papillary) necrosis. Histologically, the subcutaneous nodules were well-demarcated masses of mature, hypocellular collagen that were consistent with previous reports of nodular dermatofibrosis and renal cystadenomas or cystadenocarcinomas. In addition to diffuse acute medullary necrosis, both kidneys were affected by severe chronic lymphoplasmacytic interstitial nephritis. This is the first known report of nodular dermatofibrosis in a dog without renal cysts, cystadenoma, or cystadenocarcinoma.     

Nodular hyperplasia in the liver of the dog: an association with changes in the Ito cell population

The prevalence and morphological features of hyperplastic nodules in the liver of the dog were studied in a series of 50 consecutive post-mortem examinations. Macroscopically visible nodules were present in 35 of 50 dogs (70%), and the prevalence was related to age. The earliest age at which nodules were found was between 6 and 8 years. They were present in all dogs older than 14 or more years. The lesions were focal, multiple and consistently had evidence of a lobular pattern. There was no liver fibrosis. No direct association between previous drug administration or specific extrahepatic disease was found. Changes in the perisinusoidal fat storing cells (Ito cells) were observed in the dogs in this study. These changes comprised proliferation and hypertrophy and were recorded predominantly in dogs with hepatic nodules. The presence of a ceroid pigment was correlated with these changes. The pigment, together with lipid and macrophages, was present in the form of lipogranulomata. Lipogranulomata were observed in the parenchyma and in the portal areas of dogs with hepatic nodules. These changes may play a role in the pathogenesis of nodular hyperplasia in the liver of the dog.     

Use of antiviral medications against equine herpes virus associated disorders

Numerous types of equine herpesviruses (EHV) continue to afflict horses resulting in a variety of clinical manifestations. While many of the clinical manifestations of EHV are self‐limiting or require only supportive care, some clinical expressions of EHV infections cause severe risk to the horse's overall health and can result in abortion, long‐term deficits or death. Antiviral medications are infrequently utilised therapeutics in equine medicine and their exact efficacy is largely unknown. However, the use of antiviral medications may potentially decrease convalescent time and improve outcome in horses with EHV‐related diseases. Thus, equine practitioners should consider the potential use of antiviral medications in the future. The purpose of this article is to familiarise the equine practitioner with current information in regard to antiviral medications and their potential uses in equine medicine.     

Eyelid eosinophilic granuloma in a Siberian husky

Canine eosinophilic granuloma (CEG) is a rare skin disease of unknown origin. It has been reported in Siberian huskies, Cavalier King Charles spaniels and occasionally in other breeds. The lesions comprise nodules or plaques, mostly localised in the oral cavity. A case of a single cutaneous nodular lesion of CEG on the eyelid of a Siberian husky is described. Complete remission was achieved with oral glucocorticoid treatment.     

A review of equine sarcoid

Equine sarcoid is the most common tumour of horses and accounts for over half of all equine skin tumours. Six types of sarcoid based on gross appearance and clinical behaviour have been described including occult, verrucous, nodular, fibroblastic, mixed and malevolent. Common locations for sarcoid development include the periocular region, ear pinnae, lips, neck, extremities and ventrum (including groin region). Bovine papillomavirus (BPV) is causally associated with equine sarcoid with genetic haplotype, fly vectors and skin trauma identified as potential risk factors for development of the disease. Histopathology is required for definitive diagnosis of equine sarcoid but incomplete excision is thought to activate latent BPV and stimulate growth. Although there are no uniformly effective treatment options, several modalities have been successful in eliminating or managing equine sarcoid. Surgical excision, intratumoural chemotherapy, cryotherapy, hyperthermia, radiotherapy, immunotherapy and immune modulators are used with degrees of success relative to the accessibility and invasiveness of the tumour. Prevention of equine sarcoid may be facilitated by future development of vaccines against bovine papillomavirus.     

Equus caballus papillomavirus‐2 (EcPV‐2): An infectious cause for equine genital cancer?

Reasons for performing study: The aetiology of genital squamous cell carcinoma (SCC) in horses remains unknown, but the similarity to the disease in man, for which papillomavirus infection has been shown to be a causal factor, requires to be investigated in horses. Hypothesis: One or more novel papillomaviruses cause equine genital SCC and its associated premalignant lesions. Methods: DNA was extracted from samples of equine genital SCC and performed rolling circle amplification, in order to identify closed circular DNA viral genomes within the samples. The amplified DNA was subcloned and sequenced and the DNA sequence compared to that of other papillomavirus genomes. Using PCR primers developed from these genomic DNA sequences, studies were then carried out in order to identify the frequency at which the viral DNA could be identified in equine genital cancer samples from horses in both the UK, Australia and Austria. Finally, in situ hybridisation using specific probes developed from this DNA sequence were used to confirm the presence of the viral RNA sequences in the neoplastic cells in these lesions. Results: The full length genome of a novel papillomavirus species was characterised from the equine genital SCC tissue and termed Equus caballus papillomavirus‐2 (EcPV‐2). Viral DNA and RNA was identified in the genital tumour samples, but not in the adjacent histologically normal tissue. EcPV‐2 DNA could not be identified in equine ocular or nasal carcinomas or within the scrotal skin or in most smegma samples obtained from tumour‐free horses. Sequencing of amplicons, generated from the archived equine genital tumours, identified variations within E1 and E6 on DNA and predicted protein level. Conclusions: A novel papillomavirus, EcPV‐2, is likely to play a causal role in the pathogenesis of equine genital epithelial tumours. Potential relevance: Identification of a papillomavirus causal for genital carcinomas in horses may lead to development of a vaccine that could be used to prevent this serious disease in horses. This would be analogous to man, where vaccination against oncogenic papillomavirus species is currently being used to help prevent cervical cancer.     

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.     

The precorneal tear film in horses: its importance and disorders.

The precorneal tear film (PTF) is of critical importance in the physiologic and pathologic findings of the cornea. Clinicians should recall that quantitative and qualitative disorders of the PTF can be a cause of corneal diseases as well as a clinical sign of ocular surface diseases. It is also important to consider that some systemic and topical treatments may affect the PTF volume and composition. Not all interactions are known at this time. There is a continued need for basic research into PTF components in healthy and diseased equine eyes, because much remains unknown. Until additional basic information about the biochemical composition and pH of the PTF as well as the interactions between equine corneal pathogens and specific PTF deficits becomes available, it will not be possible to define the cause and effect relations precisely between the various ocular surface diseases and deficiencies,excesses, and imbalances of PTF components. It is quite possible that a number of equine corneal diseases may be manifestations of qualitative PTF disorders.     

Periventricular nodular heterotopia in a Chihuahua

Periventricular nodular heterotopia is a common neuronal malformation in humans, often leading to epilepsy and other neurologic diseases. A 2-month-old female Chihuahua weighing 750 g was examined because of a history of epileptic seizures and abnormalities in gait and behavior. Results of the clinical examination were consistent with a multifocal neurologic disease with localization in the forebrain and spinovestibular system. The magnetic resonance imaging showed multiple bilateral periventricular nodules isointense to gray matter and ventriculomegaly. Histopathological and immunohistological examination of the brain revealed that periventricular nodules consisted of neurons, fewer astrocytes, and some oligodendroglia consistent with periventricular nodular heterotopias.     

Immunohistochemistry of the extracellular matrix of the normal equine lamina cribrosa

Purpose To use immunohistochemical techniques to identify and localize the structural macromolecules of the extracellular matrix (ECM) of the normal adult equine lamina cribrosa in order to make comparisons to the extracellular matrix of the lamina cribrosa of horses with glaucoma. METHODS: Normal eyes of five adult horses between 5 and 10 years of age were fixed in 10% neutral buffered formalin and embedded in paraffin. Polyclonal rabbit-derived antibodies against human elastin, laminin, fibrillin-1, and collagen types I, III and IV, and polyclonal goat-derived antibodies against collagen type VI were used as primary antibodies. Transverse and longitudinal histologic sections of the optic nerve head and lamina cribrosa were stained using several dilutions of the primary antibodies, biotinylated link antibody, horseradish peroxidase-labeled streptavidin, and 3,3'-diaminobenzidine as a chromogen. The immunohistochemical staining patterns were qualitatively interpreted. RESULTS: The normal adult horse lamina cribrosa labeled positively for collagen types I, III and VI, laminin, elastin and fibrillin. Collagen type VI staining of the laminar ECM was most intense, followed by labeling for collagen types III and I, respectively. Laminar blood vessels were weakly positive for laminin and slightly positive for type IV collagen. The scleral ECM of the laminar insertion zone had more intense labeling for collagen types I and VI than did the laminar plates. CONCLUSIONS: The extracellular matrix of the laminar plates of the adult equine lamina cribrosa is similar to the dog as it consists of elastic and collagen fibers (with collagen types VI, III and I). Both the normal dog and horse lamina display more intense staining of collagen type VI than is found in the ECM of the normal human lamina cribrosa. The macromolecular structure of the equine lamina cribrosa suggests that it is a very resilient structure that may provide some protection to the optic nerve axons during episodes of elevated intraocular pressure.     

The developmental and acute phases of insulin-induced laminitis involve minimal metalloproteinase activity

Metalloproteinases have been implicated in the pathogenesis of equine laminitis and other inflammatory conditions, through their role in the degradation and remodelling of the extracellular matrix environment. Matrix metalloproteinases (MMPs) and their inhibitors are present in normal equine lamellae, with increased secretion and activation of some metalloproteinases reported in horses with laminitis associated with systemic inflammation. It is unknown whether these enzymes are involved in insulin-induced laminitis, which occurs without overt systemic inflammation. In this study, gene expression of MMP-2, MMP-9, MT1-MMP, ADAMTS-4 and TIMP-3 was determined in the lamellar tissue of normal control horses (n=4) and horses that developed laminitis after 48 h of induced hyperinsulinaemia (n=4), using quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Protein concentrations of MMP-2 and MMP-9 were also examined using gelatin zymography in horses subject to prolonged hyperinsulinaemia for 6h (n=4), 12h (n=4), 24h (n=4) and 48 h (n=4), and in normal control horses (n=4). The only change in gene expression observed was an upregulation of MMP-9 (p<0.05) in horses that developed insulin-induced laminitis (48 h). Zymographical analysis showed an increase (p<0.05) in pro MMP-9 during the acute phase of laminitis (48 h), whereas pro MMP-2 was present in similar concentration in the tissue of all horses. Thus, MMP-2, MT1-MMP, TIMP-3 and ADAMTS-4 do not appear to play a significant role in the pathogenesis of insulin-induced laminitis. The increased expression of MMP-9 may be associated with the infiltration of inflammatory leukocytes, or may be a direct result of hyperinsulinaemia. The exact role of MMP-9 in basement membrane degradation in laminitis is uncertain as it appears to be present largely in the inactive form.