Susceptibility of North-American and European crickets to Acheta domesticus densovirus (AdDNV) and associated epizootics.

The European house cricket, Acheta domesticus L., is highly susceptible to A. domesticus densovirus (AdDNV). Commercial rearings of crickets in Europe are frequently decimated by this pathogen. Mortality was predominant in the last larval stage and young adults. Infected A. domesticus were smaller, less active, did not jump as high, and the adult females seldom lived more than 10-14 days. The most obvious pathological change was the completely empty digestive caecae. Infected tissues included adipose tissue, midgut, epidermis, and Malpighian tubules. Sudden AdDNV epizootics have decimated commercial mass rearings in widely separated parts of North America since the autumn of 2009. Facilities that are producing disease-free crickets have avoided the importation of crickets and other non-cricket species (or nonliving material). Five isolates from different areas in North America contained identical sequences as did AdDNV present in non-cricket species collected from these facilities. The North American AdDNVs differed slightly from sequences of European AdDNV isolates obtained in 1977, 2004, 2006, 2007 and 2009 and an American isolate from 1988. The substitution rate of the 1977 AdDNV 5kb genome was about two nucleotides per year, about half of the substitutions being synonymous. The American and European AdDNV strains are estimated to have diverged in 2006. The lepidopterans Spodoptera littoralis and Galleria mellonella could not be infected with AdDNV. The Jamaican cricket, Gryllus assimilis, and the European field cricket, Gryllus bimaculatus, were also found to be resistant to AdDNV.

Equine herpesvirus 2-associated granulomatous dermatitis in a horse.

Granulomatous dermatitis in horses has been linked to many etiologies, including various parasites, fungi, and bacteria. Idiopathic forms of granulomatous inflammation-producing diseases, some of which are localized to the skin, also have been reported in horses. Herein we describe a case of recurrent equine granulomatous skin disease characterized by intranuclear viral inclusions within macrophages and giant cells. The histologic changes were primarily noted in the deep dermis and included multifocal to coalescing areas of necrosis marked by histiocytic cell infiltration and presence of giant cells. Electron microscopic examination revealed intranuclear and intracytoplasmic viral particles consistent with herpesvirus. Sequence results of the polymerase chain reaction product were consistent with equine herpesvirus 2, adding another possible etiology to the list of differentials in cases of equine granulomatous skin disease.

Ultrastructure of the spermatozoa from three odontocetes: a killer whale (Orcinus orca), a Pacific white-sided dolphin (Lagenorhynchus obliquidens) and a beluga (Delphinapterus leucas).

Semen was collected from three captive odontocetes: a killer whale (Orcinus orca); a Pacific white-sided dolphin (Lagenorhynchus obliquidens) and a beluga (Delphinapterus leucas). Semen was collected from the killer whale and Pacific white-sided dolphin using behavioural commands, whereas semen from the beluga was collected postmortem. Ultrastructure of the spermatozoa was examined using scanning and transmission electron microscopy. Species differences were more pronounced in the head sections followed by the midpiece and finally, the tail sections. Spermatozoa from the killer whale and beluga were similar but differed from the Pacific white-sided dolphin spermatozoa.

Ingluvial squamous cell carcinoma in a game chicken.

A 4.5-yr-old rooster was presented for a "lump on the neck." The bird exhibited dyspnea immediately prior to death. Necropsy revealed a crateriform lesion in the crop. Histologically, the lesion was diagnosed as an invasive squamous cell carcinoma, extending almost the entire thickness of the crop. Polymerase chain reaction and ultrastructural examination failed to identify a viral component. Early vascular invasion was identified.

Angiolipomatous tumors in dogs and a cat.

Variants of lipoma are uncommon, although fibrolipoma and infiltrative lipoma have been well documented. This report describes two cases of rare angiolipoma in dogs and the first documentation of angiofibrolipoma and infiltrating angiolipoma in a cat and a dog, respectively. Tumors were solitary, and most were located on the thorax of middle-aged patients. Angiolipomas were composed of mature adipose tissue mixed with variable numbers of blood vessels. In addition to the adipose and vascular components, the angiofibrolipoma contained bundles of collagenous connective tissue. The infiltrative angiolipoma had a primary mass external to the muscle and was histologically similar to a mixed intramuscular hemangioma that was confined to the muscle. Both disrupted bundles of striated muscle and were associated with segmental degeneration and loss of myofibers.

Endometritis in postparturient cattle associated with bovine herpesvirus-4 infection: 15 cases.

Suppurative, ulcerative endometritis associated with bovine herpesvirus-4 (BHV-4) infection was identified in 15 postparturient dairy cows from 5 separate dairies. Characteristic eosinophilic to amphophilic intranuclear viral inclusion bodies were identified within degenerate endometrial lining epithelium and endothelial cells. Bovine herpesvirus-4 was confirmed as the etiology by a combination of fluorescent antibody assays, viral isolation, heminested PCR, ultrastructural examination of the uterus and inoculated tissue culture cells, and negative-stain electron microscopy of tissue culture supernatant. Viral particles measuring 70-95 nm were demonstrated in uterine epithelial and endothelial cells by electron microscopy. Bacteria including Arcanobacterium pyogenes, Escherichia coli, and an alpha-Streptococcus isolate were isolated from all uteri. Bovine herpesvirus-4-associated endometritis has been previously reported in sporadic cases in Europe but has not been previously reported in the United States. Endometritis associated with BHV-4 appears to be an emerging syndrome in Georgia dairy herds.

The potential toxicity of Ilex myrtifolia in beef cattle.

Spatial and temporal patterns of death loss in a beef cowherd indicated a possible relationship between the loss of 11 cows and the consumption of Ilex myrtifolia (myrtle leaf holly). To investigate this relationship, plant material from Ilex myrtifolia was harvested and 2 feeding trials were performed. The 1st trial involved intermittent feeding of plant material to 4-mo-o calves for 2 w, and the 2nd trial was continuous plant feeding to 2-mo-o calves for 35 d. No significant clinical pathology, histological or gross lesions resulted and no clinical signs consistent with the original herd problem were observed, suggesting that berries, leaves and stems from Ilex myrtifolia were not sufficiently toxic to induce clinical effects under these experimental conditions.

Connective tissue growth factor expression in the rat remnant kidney model and association with tubular epithelial cells undergoing transdifferentiation.

Connective tissue growth factor (CTGF) has been shown to mediate many actions of transforming growth factor-beta (TGF-beta) in the fibrotic response in several diseases. We compared expression of CTGF, TGF-beta, platelet-derived growth factor (PDGF), TNF-alpha, and interleukin-1 (IL-1) by in situ hybridization in Sprague-Dawley rats euthanized at 0, 2, 4, and 8 weeks after 5/6 nephrectomy using the rat remnant kidney model of renal failure. Collagen was evaluated by trichrome stains, immunohistochemistry, and electron microscopy. We compared expression patterns to cells undergoing metaplasia. Tubular epithelial regeneration and transdifferentiation to myofibroblasts were assessed morphologically and by proliferating cell nuclear antigen, smooth muscle actin, desmin, and vimentin immunohistochemistry. CTGF expression was minimal in controls, mild at 2 weeks and marked by 4 to 8 weeks in interstitial fibroblasts, coinciding with damage, regeneration, and fibrosis. TGF-beta expression was increased in many cell types at 2 weeks, increased further by 4 weeks, then remained constant. PDGF-B messenger RNA was found in many stromal cells at 2-4 weeks, but expression decreased at 8 weeks. No significant IL-1 or TNF-alpha staining was detected. We conclude that CTGF and interacting factors are associated with development or progression of chronic interstitial fibrosis. Proximity of CTGF, TGF-beta, and PDGF mRNA expression to regenerative epithelial cells and those transdifferentiating to myofibroblasts suggests that growth factors may modulate renal tubular epithelial differentiation.

Mushroom toxicity in a horse with meningioangiomatosis.

We describe a fatal case of mushroom intoxication in an 18-y-o horse presumably due to Amanita verna. Horses are normally regarded as too fastidious to eat the ill-flavored toadstools. In this case, the horse had a rare benign brain tumor, meningioangiomatosis, which may have altered the horse's normal eating behavior resulting in consumption of the mushrooms.

Effects of macrophage inhibitory factor-A3 (MIF-A3) on cytokine secretion and phagolysosome fusion in murine macrophages.

Macrophage inhibitory factor-A3 (MIF-A3) is a fraction derived from Mycobacterium avium serovar 2 (Mav2) that consists of a small amine containing compound (peptide), trehalose and two or three short chain fatty acids. MIF-A3 has been shown to inhibit candidacidal activity of murine thioglycolate-elicited peritoneal-derived macrophages and bovine peripheral blood monocytes, and scavenge reactive oxygen intermediates. In this study, MIF-A3 was evaluated for its effect on secretion of IL-1beta, IL-6, IL-10, TNFalpha and GM-CSF in C57BL/6 murine thioglycolate-elicited peritoneal-derived macrophages, with and without pre-incubation with affinity purified goat anti-MIF-A3 IgG, using ELISA cytokine kit analysis. Results of this study suggest that anti-MIF-A3 IgG does not enhance clearance of Mav2, alter phagocytosis or alter phagosome-lysosome interactions as determined by electron microscopy in Mav2 infected macrophages. MIF-A3 does induce secretion of IL-6, but does not induce secretion of TNFalpha, IL-1beta, and GM-CSF. TNFalpha has been previously shown to reduce growth, while IL-6 has been shown to enhance growth of M. avium. Since IL-6 appears to enhance growth of M. avium and MIF-A3 induces IL-6 secretion, MIF-A3 may be responsible for enhanced intracellular growth in M. avium infections and be a factor in the pathogenesis of M. avium infections.

Multiple persistent vitelline duct cysts in a dog.

Persistent vitelline duct remnants, with the exception of Meckel's diverticulum in pigs and horses, are rare in animals. During an ovariohysterectomy of an 8-month-old Labrador Retriever, multiple fibrous nodules with cystic centers were found attached to the ileal serosa and in a mesodiverticular band attached to the abdominal wall. Histologic and ultrastructural evaluation revealed that the cysts were composed of well-differentiated intestine with mucosa, submucosa, and muscularis layers surrounded by a thick layer of fibrous connective tissue. The morphology and arrangement of lesions were consistent with multiple persistent vitelline duct cysts, a distinct condition related to Meckel's diverticulum. This case in a dog represents a unique presentation of this congenital anomaly in domestic animals.

Comparison of field-collected ascovirus isolates by DNA hybridization, host range, and histopathology.

Six field-collected ascovirus isolates obtained from five noctuid species in the continental United States were compared with respect to the general relatedness of their DNA, host range, and histopathology. Two isolates were from Spodoptera frugiperda, and the other four were from Autographa precationis, Heliothis virescens, Helicoverpa zea, and Trichoplusia ni. DNA-DNA hybridization studies showed that the six isolates belonged to three distinct viral species, with the isolates from S. frugiperda composing one species, those from A. precationis and H. virescens a second species, and those from H. zea and T. ni a third species. The host range and histopathology of each isolate was studied in eight noctuid species, S. frugiperda, Spodoptera ornithogalli, Spodoptera exigua, Spodoptera eridania, H. virescens, H. zea, A. precationis, and Feltia subterranea. Though some variation existed between the different isolates of each viral species, distinct patterns were apparent for each. The viral species from S. frugiperda had a host range that was limited primarily to Spodoptera species and both isolates of this virus only replicated and caused significant pathology in the fat body, whereas the viral species from A. precationis and H. virescens had a much broader host range that included most of the species tested, but also had a tissue tropism primarily restricted to the fat body. The viral species from T. ni and H. zea readily infected all the hosts tested, where the principal site of replication and significant pathology was the epidermis. In many test hosts, however, this viral species also replicated and caused significant pathology in the tracheal epithelium and to a lesser extent in the fat body. Aside from contributing to knowledge of ascovirus biology, these studies indicate that DNA hybridization profiles combined with studies of host range and tissue tropism can be used as characters for defining ascovirus species.

Microcystin toxicosis in cattle due to overgrowth of blue-green algae.

Toxicosis due to microcystin-containing blue-green algae has been sporadically reported in a variety of animal species. Most reports of intoxication involve algal blooms during periods of warm temperatures and abundant sunshine in the spring or early summer. A case of blue-green algae toxicosis with lesions attributable to toxins from Microcystis aeruginosa is described in 4 cattle from southern Georgia during November. The case was unusual in that characteristic hepatic necrosis was accompanied by severe mesenteric edema and peritoneal effusion. In addition, weather conditions and location were not expected to be conducive to algal blooms. Rapid diagnosis and identification of the probable source of intoxication allowed the owner to move the herd away from the affected pond. This action limited losses to only the 4 cattle.

Combined adenovirus and rotavirus enteritis with Escherichia coli septicemia in an emu chick (Dromaius novaehollandiae).

A 2-week-old emu chick (Dromaius novaehollandiae) of approximately 200 g body weight was presented for necropsy with a history of weakness, diarrhea, pallor of the head, and acute death. Hemorrhagic enteritis with mild hepatomegaly was noted on gross examination. Microscopic examination revealed necrohemorrhagic enteritis with intralesional intranuclear basophilic viral inclusion bodies in intestinal epithelial cells; splenic lymphoid necrosis and fibrin exudation; hepatocellular vacuolar change; and multiple clusters of small gram-negative bacilli in the liver, spleen, yolk sac, and intestine. Transmission electron microscopy of negatively stained fecal specimens and thin sections of small intestine revealed clusters of viral particles consistent with adenovirus and rotavirus. Attempts at viral isolation from pooled tissue specimens were unsuccessful. Escherichia coli was isolated from specimens of liver and intestine and from an abdominal swab.

Disseminated adenovirus infection associated with cutaneous and visceral hemorrhages in a nursing piglet.

An unusual adenovirus infection in a conventionally raised nursing pig was characterized clinically by hemorrhagic diathesis of the skin and microscopically by disseminated viral inclusions in the endothelial, interstitial, and epithelial cells of the skin, kidney, spleen, liver, heart, and small and large intestines. This disease was confirmed ultrastructurally by demonstration of typical adenoviral particles in the nuclei of endothelial cells in the myocardium and of interstitial cells in the small intestine. This is the first report of disseminated adenovirus infection in a nursing pig in North America.

Isolation of Acanthamoeba sp. from a greyhound with pneumonia and granulomatous amebic encephalitis.

Acanthamoeba were isolated from a naturally occurring animal infection of granulomatous amebic encephalitis. The amebas were grown from lung lesions from a 1-year-old greyhound puppy, which was 1 of several dogs in a kennel that was affected by a progressive fatal neurologic and respiratory disease. The Centers for Disease Control, Atlanta, Georgia, confirmed the disease to be acanthamebiasis and specifically identified the amebas as Acanthamoeba culbertsoni by fluorescent antibody testing on brain tissue from the dog. The amebas were cultured initially on potato dextrose agar and on nonnutrient agar plates that were seeded with a lawn of nonpathogenic Escherichia coli. The isolate was then transferred to nonnutrient agar plates containing killed Enterobacter aerogenes and subsequently to axenic medium and cell cultures. The isolate was highly pathogenic by intranasal inoculation into 2-week-old mice.

Fatal disease in nursing puppies associated with minute virus of canines.

Thirteen cases of a previously undescribed parvoviral infection affecting puppies ranging in age from 5 to 21 days is described. The cases were originally thought to represent an unusual pathologic manifestation of canine parvovirus-2 (CPV-2) infection. However, failure to confirm CPV-2 infection in any of the cases suggested a different parvovirus was involved. Minute virus of canines (MVC) was subsequently isolated from a case by using the Walter Reed Canine Cell Line, the only cell line which will support the growth of MVC. The pathologic and virologic findings for these 13 cases are described in this report.

Clinical and pathologic features of ceroid lipofuscinosis in two Australian cattle dogs.

A lysosomal storage disease was diagnosed in 2 Australian Cattle Dog siblings, using light and electron microscopic evaluation. Both dogs developed clinical signs of disease at about 1 year of age. Vision and motor function deteriorated over several months; by 2 years of age, the dogs were blind and had progressive ataxia. Cytoplasmic inclusions with ultrastructural patterns characteristic of ceroid lipofuscin were observed in most neurons examined and in the cells of several other parenchymatous tissues. Biochemical studies, including determination of lysosomal enzyme activities, excluded several other lysosomal storage diseases. In these dogs, the clinical and pathologic features of the disease were similar to those of the juvenile subtype of ceroid lipofuscinosis (Batten disease) in human beings.