Isolation and partial characterization of bovine foamy virus from Polish cattle

The first isolation and partial characterization of bovine foamy virus (BFV), also known as bovine syncytial virus, in Poland is described. This virus was isolated by co-cultivation of peripheral blood leukocytes from infected cattle with permissive Cf2Th cells. The new isolate, called BFV100 was identified using several techniques: electron microscopy, western blotting, PCR and sequencing of a part of the gag and pol/env genes. Based on syncytia induction, antigenic determinants, primer binding sites and sequence analysis, it can be concluded that isolate BFV100 is bovine foamy virus and is related to the known American and German BFV isolates by sequence homology and antigenic relatedness.     

Evaluation of formalin-fixed paraffin-embedded tissues from feline vaccine site-associated sarcomas for feline foamy virus DNA

OBJECTIVE: To evaluate a group of vaccine site-associated sarcomas (VSS) for the presence of feline foamy virus (FeFV) DNA, using polymerase chain reaction (PCR) methods. SAMPLE POPULATION: 50 formalin-fixed paraffin-embedded (FFPE) tissue blocks from VSS of cats. PROCEDURE: DNA was extracted from FFPE sections of each tumor, and regions of the gag and pol genes of FeFV were amplified by use of PCR methods, using 1 primer set for each region. Sensitivity of the method was compared between fresh and FFPE cells, using mouse kidney tissue that was injected with FeFV-infected cultured cells and using agarose-cell pellets. Results-Feline foamy virus DNA was not detected in VSS tissues. Sensitivity of the method was 10 times greater in fresh versus FFPE mouse tissues. Sensitivity of the method in fresh FeFV-infected cultured cells versus FFPE agarose-cell pellets was equal when fixation was 24 or 48 hours and 10 times greater when fixation was 72 hours or 1 week. CONCLUSIONS AND CLINICAL RELEVANCE: A PCR-based method can be successfully applied to FFPE tissues for FeFV DNA detection. Results suggest there is no direct FeFV involvement in the pathogenesis of VSS in cats.     

Pathologic effects of intrauterine deposition of pseudorabies virus on the reproductive tract of swine in early pregnancy

Pseudorabies virus was inoculated into the uterus of 15 gilts within 6 hours after natural breeding, and gilts were necropsied at postbreeding days (PBD) 3, 6, 10, 14, and 28; 3 control gilts were treated similarly, except for inoculation with pseudorabies virus and were necropsied at PBD 6, 10, and 14. Tissues were collected for virus isolation, fluorescent antibody staining, and histopathologic examination. Pseudorabies virus was isolated from the reproductive tract up to day 14. Lesions in the reproductive tract consisted of multifocal to diffuse lymphohistiocytic vaginitis and endometritis, and lymphoplasmacytic aggregates in the corpora lutea. Multiple ulcers were seen in the vagina or endometrium of several gilts at PBD 3, 6, and 10. Corpora lutea of 1 gilt were necrotic at PBD 14 and contained large numbers of inflammatory cells. Focal aggregates of lymphocytes and plasma cells were seen in vagina and endometrium of 3 gilts and in the ovary of 1 gilt at day 28.     

Contrastive prevalence of feline retrovirus infections between northern and southern Vietnam

The prevalence of infections with three feline retroviruses; feline leukemia virus (FeLV), feline immunodeficiency virus (FIV) and feline foamy virus (FeFV), was examined in domestic cats (Felis catus) and leopard cats (Felis bengalensis) in southern Vietnam in 1998. We then compared this data with our previous study in northern Vietnam in 1997. None of the cats had FeLV antigens in both the northern and southern areas. In contrast, there is a great distinction in the seropositivity of FIV. Twenty-two percent of domestic cats had FIV antibodies whereas no FIV positive cats were detected in northern area. FIV may have entered southern Vietnam recently and spread rapidly. FeFV infections were found in both areas, suggesting that FeFV might be present in the cat populations in Vietnam from the earliest time.     

Pathogenesis and prevention of placental and transplacental porcine reproductive and respiratory syndrome virus infection

Porcine reproductive and respiratory syndrome virus (PRRSV)-induced reproductive problems are characterized by embryonic death, late-term abortions, early farrowing and increase in number of dead and mummified fetuses, and weak-born piglets. The virus recovery from fetal tissues illustrates transplacental infection, but despite many studies on the subject, the means by which PRRSV spreads from mother to fetus and the exact pathophysiological basis of the virus-induced reproductive failure remain unexplained. Recent findings from our group indicate that the endometrium and placenta are involved in the PRRSV passage from mother to fetus and that virus replication in the endometrial/placental tissues can be the actual reason for fetal death. The main purpose of this review is to clarify the role that PRRSV replication and PRRSV-induced changes in the endometrium/placenta play in the pathogenesis of PRRSV-induced reproductive failure in pregnant sows. In addition, strategies to control placental and transplacental PRRSV infection are discussed.     

A case of feline leprosy caused by Mycobacterium lepraemurium originating from the island of Kythira (Greece): diagnosis and treatment

A 2-year-old, 4 kg, healthy, domestic shorthair female cat presented with ulcerated subcutaneous nodules on the commissures of its mouth. The cat was negative for feline leukaemia virus and feline immunodeficiency virus. Skin mycobacteriosis was diagnosed after detection of numerous acid-fast bacilli in Ziehl Neelsen-stained smears from the ulcers. Feline leprosy was suspected following preliminary polymerase chain reaction results: positive for Mycobacterium genus but negative for Mycobacterium tuberculosis and Mycobacterium avium complexes. Mycobacterium lepraemurium was later identified following DNA sequence analysis of the 5' end of the 16S rRNA gene and the 16S-23S internal transcribed spacer region. Microscopic lesions consisted of pyogranulomas containing mainly large foamy macrophages with 10-100 intra-cellular acid-fast bacilli per field. The cat was cured after surgery and a 14-week course of clofazimine (30 mg daily) and clarithromycin (50 mg twice daily).     

Characterization of Env antigenicity of feline foamy virus (FeFV) using FeFV-infected cat sera and a monoclonal antibody

To characterize neutralizing antigenicity in relation to env genotypes of feline foamy virus (FeFV), serological analyses were performed using FeFV-infected cat sera and several field isolates including two env genotypes (F17- and FUV-types). Since three cats from which FeFV were isolated were found to have undetectable titers of virus neutralization (VN) antibodies, even to the homologous virus, VN antibodies were further examined with complement supplementation as an enhancement factor. With the presence of complement, the VN titers of FeFV-infected cat sera increased drastically. Although most of serum samples neutralized strains of either env genotype, sera sampled from two cats neutralized all the strains examined at similar titers, suggesting that superinfection with both env genotypes of FeFV might have occurred in the two cats. Further, we produced a monoclonal antibody (mAb) specifically neutralizing FeFV strains of FUV-type. The mAb was shown to have higher affinity to an epitope on Env of FUV-type than that of F17-type by immunoprecipitation assay. This study supplies basic information important for studies on FeFV vector development as well as on the relationship between the virus and the host immune response.     

Effect of EDTA on morphology of neutrophils of healthy dogs and dogs with inflammation

Increased basophilia and foamy vacuolation in the cytoplasm of neutrophils in smears made within 1 hour of blood collection suggest inflammatory disease. Due to the mild increase in foamy vacuolation which occurred with time in EDTA, the significance of mildly vacuolated neutrophils in smears prepared a few hours after blood collection is questionable. However, moderate or severe foamy vacuolation should be considered clinically significant. In vitro morphologic changes in neutrophils from healthy dogs in EDTA include clear, discrete vacuoles in the cytoplasm, uneven distribution of cytoplasmic granules, irregular cell membrane and pyknosis. These neutrophils generally lack basophilia, have minimal foamy vacuolation of the cytoplasm and are morphologically different from neutrophils associated with severe inflammation.     

Morphometric studies of the bovine uterus: microscopic lesions and retrospective reproductive history

A survey of reproductive tracts from nonpregnant cows at an abattoir was conducted. Reproductive tracts from 98 cows were studied microscopically and evaluated with a grading system to determine the severity of pathologic changes. Inflammatory reaction (type and distribution), fibrosis, gland morphology, and appearance were measured, quantified, and scored (1 to 4). Category 1 endometrium (normal) was found in 18 cows, category 2 in 23, category 3 in 34, and category 4 in 23. The category of endometrium was then compared with the retrospective reproductive status, and it was found that reproductive problems had occurred in 6 cows (33.3%) in category 1, in 13 cows (56.5%) in category 2, in 25 cows (73.5%) in category 3, and in 21 cows (91.3%) in category 4. Cervicitis was found in 43 (43.8%) genital tracts; 16 cows (16.3%) had salpingitis. Ovarian lesions were not observed. Serum samples were tested for certain antibodies. Only 1 was seropositive for brucellosis, but 61 of 81 sera had leptospira titers greater than 1:100 and 1:50 (hardjo). The serovar hardjo was the most prevalent. All sera had neutralizing titers against parainfluenza type 3 virus; 74.2% and 56.7% of the sera had neutralizing antibodies against bovine viral diarrhea virus and infectious bovine rhinotracheitis virus, respectively.     

Bronchioloalveolar carcinoma not related to jaagsiekte sheep retrovirus in a goat

A spontaneous lung tumor in a 5-year-old goat of the Murciano-Granadina breed is described in this paper. Clinical signs of cachexia and tachypnoea were evident, and a considerable amount of white mucous foamy fluid was discharged from the nostrils when the animal's head was lowered. A lung tumor with the characteristics of bronchioloalveolar carcinoma was detected during histopathologic examination. The tumor cells were positive for surfactant proteins C and B, confirming that alveolar type II cells were the origin of the neoplasia. Tumor samples were tested by polymerase chain reaction, immunoblotting, and immunohistochemistry for the presence of Jaagsiekte sheep retrovirus (JSRV) and enzootic nasal tumor virus (ENTV), another retrovirus very closely related to JSRV, but all tests were negative. Therefore, this is the first reported case of spontaneous bronchioloalveolar carcinoma not related to JSRV or ENTV infection in a goat.     

Pathological features of salivary gland cysts in a Shiba dog with GM1 gangliosidosis: a possible misdiagnosis as malignancy

Salivary gland cysts are often concurrent with GM1 gangliosidosis in Shiba dogs. Although the etiology is unknown, these cysts may be misdiagnosed as malignant due to the accumulation of foamy cells. The present study investigated the cytological, histopathological, immunohistochemical and electron microscopic characteristics of salivary gland cysts in a Shiba dog affected with GM1 gangliosidosis. The salivary gland masses were surgically enucleated and examined clinicopathologically and pathologically in a 7-month-old Shiba dog with GM1 gangliosidosis. Many large cells with rich cytoplasm including vacuoles of various sizes, i.e., foamy cells, were observed in stamp smears from the cut-surface of the masses and histopathologically in major parts of the cyst wall. Some of these foamy cells presented features similar to a spider-web appearance. The foamy cells were confirmed to have originated from macrophages based on marked immunohistochemical expression of vimentin, HLA-DR, lysozyme and Iba1. An ultrastructural study demonstrated electron-dense vesicular structures in the vacuolated cells. Therefore, the masses were diagnosed pathologically as benign salivary gland cysts with accumulation of foamy cells. In conclusion, the histopathological features of the salivary gland cysts in this Shiba dog were similar to those of lipoma and/or liposarcoma. In such cases, immunohistochemical and ultrastructural examinations were useful in the differential diagnosis. Practitioners, clinical pathologists and pathologists should take GM1 gangliosidosis into consideration when they encounter salivary gland cysts in Shiba dogs.     

Xanthogranulomatous inflammation of the small bowel in a dog

A case of xanthogranulomatous inflammation of the small bowel in a 12-year-old male American Staffordshire Terrier is described. Disseminated yellow-white nodules 2 to 3 mm in diameter bulging on the serosal surface of the small bowel, as well as on mesenteric tissue, were detected. Histopathologic examination revealed a nodular collection of foamy cells, mainly involving serosal and muscular layers, associated with necrotic areas, hemorrhages, neovascularization, variable numbers of reactive spindle cells, neutrophils, lymphocytes, plasma cells, and rare multinucleated giant cells. Transmural lymphangectasia and mucosal lymphoplasmacytic inflammation were also observed. Both Oil Red O stain and ultrastructural study revealed lipid droplets in the cytoplasm of foamy cells. Lysozyme immunoreactivity was detected in single as well as in clustered foamy cells, while smooth muscle actin was positive in spindle cells and scattered foamy elements. Lymphangectasia associated with lymphoplasmacytic enteritis suggests a component of lymphatic fluid stasis in the pathogenesis of such lesions.     

Leprosy in a chimpanzee. Morphology of the skin lesions and characterization of the organism.

Microscopic features of lepromatoid lesions in a chimpanzee inoculated with bovine leukemia virus consisted of diffuse dermal infiltrations of foamy histiocytes, except for a subepidermal "clear zone" devoid of infiltrating cells. Acid-fast organisms were in histiocytes, dermal nerves and a branch of the left radial nerve. The organisms were more intensely acid-fast with the Fite-Faraco than with the Ziehl-Neelsen stain. The organisms did not oxidize 3,4-dihydroxyphenylalanine (dopa) to indole but their acid-fast staining quality was removed by pretreatment with pyridine. Human leprosy patients, inoculated simultaneously with chimpanzee and human lepromin, reacted similarly to both lepromins. Organisms, when inoculated into mouse footpads, multipllied in 6 months to a quantity that was compatible with their identification as Mycobacterium leprae.     

Hydrops amnii in sheep associated with hydranencephaly and arthrogryposis with wesselsbron disease and rift valley fever viruses as aetiological agents.

During the 1974/75 lambing season numerous reports were received from various parts of the Republic of South Africa and South West Africa of severe abdominal distension in ewes after vaccination with the attenuated Rift Valley fever and/or attenuated Wesselsbron disease vaccine. The ewes were vaccinated at different stages of gestation in spite of recommendations to the contrary, the syndrome being especially obvious in ewes immunized with one or both of these vaccines during the first trimester of pregnancy. In some of the flocks hydrops amnii was recorded in as many as 15% of the ewes. Many of the ewes so affected showed a prolonged gestation of up to 6-7 months and, towards the end of gestation, were unable to rise or walk. They eventually died of ketosis, hypostatic pneumonia and complications due to dystocia. The foetuses examined were malformed and larger than normal with a mass of 3,6-6,7 kg. They usually showed arthrogryposis, brachygnathy inferior, hydranencephaly, hypoplasia or segmental aplasia of the spinal cord and neurogenic muscular atrophy. The amnion contained 8,0-18,0 1 of amniotic fluid, the endometrium was oedematous, and cystic tube-like dilatations, 1-10 mm in diameter, filled with a clear fluid, were scattered in the endometrium. No definite conclusions as to the aetiology of the syndrome could be drawn from serological tests performed on the ewes, lambs or foetuses. Preliminary experimental work confirmed previous observations that the attenuated Wesselsbron disease vaccine virus is responsible for this syndrome and that the wild-type virus is also implicated. In addition, the attenuated Rift Valley fever vaccine virus was found to the responsible for arthrogryposis and hydranencephaly without hydrops amnii and for micrencephaly and arthrogryposis associated with hydrops amnii in the ewe.     

Implications of simian retroviruses for captive primate population management and the occupational safety of primate handlers.

Nonhuman primates can be naturally infected with a plethora of viruses with zoonotic potential, including retroviruses. These simian viruses present risks to both captive nonhuman primate populations and persons exposed to nonhuman primates. Simian retroviruses, including simian immunodeficiency virus, simian type D retrovirus, simian T-lymphotropic virus, and gibbon ape leukemia virus, have been shown to cause clinical disease in nonhuman primates. In contrast, simian foamy virus, a retrovirus that is highly prevalent in most nonhuman primates, has not been associated with clinical disease in naturally infected primates. Although it has been shown that human retrovirus infections with human T-lymphotropic virus and human immunodeficiency virus originated through multiple independent introductions of simian retroviruses into human populations that then spread globally, little is known about the frequency of such zoonotic events. In this article, exogenous simian retroviruses are reviewed as a concern for zoo and wildlife veterinarians, primate handlers, other persons in direct contact with nonhuman primates, and other nonhuman primates in a collection. The health implications for individual animals as well as managed populations in zoos and research institutions are discussed, the cross-species transmission and zoonotic disease potential of simian retroviruses are described, and suggestions for working safely with nonhuman primates are provided.     

Molecular characterization of bovine foamy virus and its association with bovine leukemia virus infection in Vietnamese cattle

The detection of bovine foamy virus (BFV) in Vietnamese cattle was performed using conventional PCR targeting pol and gag genes. Out of 243 tested samples, ten (4.1%) and eight (3.3%) samples were positive for BFV gag and pol DNA, respectively. The prevalence of bovine leukemia virus (BLV) estimated by detection of proviral DNA using nested PCR targeting env gene was 26.7% (65/243). The results of nucleotide sequence alignment and the phylogenetic analysis suggested that Vietnamese BFV strains showed high homology to isolates belonging to either European or non-European clades. There was no significant correlation between BLV and BFV. This study provides information regarding BFV infection and confirms the existence of two BFV clades among Vietnamese cattle for the first time.     

Lectin histochemistry of foam cells in tissues of cattle grazing Brachiaria spp

Brachiaria decumbens and B. brizantha (signal grass), which occupy millions of acres in Brazil, are an important source of fodder for ruminants. Sporadic outbreaks of photosensitization in ruminants grazing on signal grass have been reported. Intoxicated animals showed the presence of foamy cells in the liver, spleen, intestinal submucosa and lymph nodes. These foamy cells are macrophages. They are very difficult to distinguish with haematoxylin and eosin stain, especially in the case of isolated cells. The purpose of the present study was to detect specific carbohydrate residues of storage material in the foamy cells in tissues of cattle exposed to Brachiaria spp. The characterization of glycoconjugates provides clues to the pathogenesis of these cells. Besides, the lectin peanut agglutinin was found to be an excellent marker to differentiate and quantify the foam cells, and could be used as a specific marker.     

Genomic characterization and distribution of bovine foamy virus in Japan

Bovine foamy virus (BFV) is distributed through worldwide cattle herds. Although the biological features of BFV are not well understood, appearance of clinical manifestation by superinfection with other microorganisms is inferred. In Japan, reports of genomic characterizations and epidemiology of this virus are limited. In this study, we performed whole genomic sequencing of BFV strains Ibaraki and No.43, which were isolated in this country. Additionally, we investigated BFV in geographically distant four daily farms in Japan, to estimate the distribution of BFV and its correlation to bovine leukemia virus (BLV). BFV was distributed throughout Japan; the average positive rate was 12.7%. The nucleotide sequence identities of the isolates were 99.6% when compared with BFV strain isolated in the USA. The phylogenetic tree using env gene sequence showed strains Ibaraki, No.43 and Kagoshima were sorted in the same cluster including the USA and Chinese strains, while Hokkaido strain was in the other cluster including European strains. Although no clear correlation between BFV and BLV could be found, BFV and BLV infections were likely to increase with ages. Our data on epidemiology and characteristics of BFV will provide important information to reveal biological features of BFV.     

Proliferative vasculopathy and cutaneous hemorrhages in porcine neonates infected with the porcine reproductive and respiratory syndrome virus

Severe cutaneous hemorrhages with dermal and subcutaneous capillary angioplasia were seen in aborted and stillborn piglets, concurrently with an acute outbreak of porcine reproductive and respiratory syndrome virus (PRRSV) abortions. Histologically, the lesions consisted of angioblastic endothelial cells and immature capillary vascular structures coursing through the edematous myxomatous dermis and subcutis. Proliferating capillaries often were surrounded by large and foamy macrophages that stained positively for PRRSV by immunohistochemistry. The sudden appearance of these vascular lesions during the PRRSV outbreak and their abrupt disappearance after the abortion storm, along with the immunohistochemical localization of PRRSV-positive macrophages adjacent to the proliferating capillaries, suggest that PRRSV likely played a role in the development of these unusual lesions.     

secretion of the major progesterone-induced proteins of the sheep uterus by caruncular and intercaruncular endometrium of the pregnant ewe from days 20–140 of gestation

An experiment was performed to evaluate the types and quantity of proteins secreted by intercaruncular endometrium at days 20, 60, 100 and 140 of gestation and caruncular endometrium from days 100 and 140 of gestation. Tissues were obtained from ewes made unilaterally pregnant. Based on SDS polyacrylamide gel electrophoresis (SDS-PAGE), the major proteins present in uterine fluid at days 60–140 of gestation were the uterine milk proteins (UTM-proteins), a pair of structurally-related, progesterone-induced polypeptides with molecular weights of 55,000 and 57,000. These proteins were also present in uterine fluid at day 20, but the major protein at this time migrated coincident with albumin. Cultured explants of endometrium at all days of pregnancy produced UTM-proteins as their major radiolabelled product for both caruncular and intercaruncular endometrium. The amount of protein secretion in vitro was greater (P<.04) for intercaruncular endometrium than for caruncular endometrium but was not significantly affected by stage of gestation or local presence of the conceptus. Immunohistochemical analysis revealed that UTM-proteins were present in glandular and luminal epithelium of intercaruncular endometrium and in both epithelial and stromal elements of caruncular endometrium. It was concluded that the UTM-proteins are produced earlier than previously described (i.e., day 20). In addition, caruncles contribute to the uterine secretory protein milieu through the secretion of proteins that are similar to that produced by the glandular intercaruncular epithelium.