Multilocus characterization of Sarcocystis falcatula-related organisms isolated in Brazil supports genetic admixture of high diverse SAG alleles among the isolates.

In a previous study in Brazil, six isolates of Sarcocystis spp. recovered from budgerigars fed sporocysts excreted by opossums of the genus Didelphis were characterized by means of sequencing fragments of gene coding cytochrome B (CYTB), internal transcribed spacer 1 (ITS1), and surface antigen genes (SAG2, SAG3 and SAG4). The isolates shared identical ITS1 and CYTB sequences, but differed at SAG2, SAG3 and SAG4: three allele variants of SAG2, 3 allele variants of SAG3 and 2 allele variants of SAG4 were encountered in three multilocus genotypes (MLGs) (MLG1, MLG2, and MLG3). At ITS1 and CYTB, all the isolates from budgerigars were identical to the Sarcocystis falcatula-like isolate 59-2016-RS-BR that was detected in a barefaced ibis (Phimosus infuscatus) causing necrotizing meningoencephalitis in Brazil. At ITS1 locus, all the above isolates were clearly distinct from Sarcocystis neurona, Sarcocystis falcatula, Sarcocystis lindsayi, and Sarcocystis speeri, the four known species of Sarcocystis that use opossums of the genus Didelphis as definitive hosts. Here, we replicated the experiment above to identify additional MLGs or other species of Sarcocystis. Fifteen budgerigars were experimentally infected with sporocysts of Sarcocystis spp. from 12 opossums of the genus Didelphis. All the birds died 9-19 days after infection and tissue samples containing merozoites and schizonts of Sarcocystis spp. were recovered. Fractions of sequences coding for 18S ribosomal RNA gene (18S), CYTB, ITS1, SAG2, SAG3 and SAG4 were PCR amplified and sequenced from the infected lungs. In addition, fractions of 18S, SAG2, SAG3 and SAG4 were sequenced from the isolate 59-2016-RS-BR and fractions of 18S were sequenced from the six isolates from budgerigars described above. From the results, all the isolates shared identical 18S, ITS1 and CYTB sequences. Among the 15 new isolates from budgerigars, three allele variants of SAG2, 3 allele variants of SAG3 and 2 allele variants of SAG4 were encountered in five MLGs, of which four were novel (MLG1, MLG4, MLG5, MLG6 and MLG7). Isolate 59-2016-RS-BR was assigned to an eighth MLG (MLG8). Molecular data pointed that Sarcocystis assigned to MLGs 1 to 8 are variants of the same species, but the SAG-based trees of the isolates conflicted, which supports genetic admixture among them. The sarcocystinae studied have high diversity of SAG alleles per locus and the correlation of such an abundant variety of SAG alleles to host specificity and pathogenicity needs to be assessed. Remains to be elucidated if the parasites studied here and S. falcatula are variants of the same species that have diverged to the point of possessing differences at ITS1 level, but that are still capable of exchanging genes.

Granulomatous Necrotizing Myositis in Swine Affected by Porcine Circovirus Disease.

Porcine circovirus type 2 (PCV2) is associated with multiple clinical syndromes in pigs, known as porcine circovirus diseases. This work describes an outbreak of porcine circovirus diseases with severe lesions affecting the skeletal muscle. Ninety-two pigs had apathy, weight loss, and diarrhea over a clinical course of 7 to 10 days. Approximately 30 of the pigs had stiff gait, muscle weakness, hind limb paresis, and recumbency. Twelve of the 92 pigs were necropsied, and 4 had pale discoloration of skeletal muscles with microscopic lesions of granulomatous necrotizing myositis. Immunohistochemistry of skeletal muscle showed that PCV2 antigen was located primarily in the cytoplasm and nuclei of macrophages, lymphocytes, and multinucleated giant cells, with a lower amount in the cytoplasm of endothelial cells, necrotic fibers, and satellite cells. Affected muscle samples were polymerase chain reaction-positive for PCV2 and the amplicon exhibited 99% identity with sequences belonging to the PCV2b genotype. Locomotor clinical signs and granulomatous necrotizing myositis should be considered as another expression of PCV2 infection in pigs.

Necrotizing meningoencephalitis caused by Sarcocystis falcatula in bare-faced ibis (Phimosus infuscatus).

The infection by S. falcatula is commonly associated with respiratory disease in captive psittacine birds, with a few case reports of this protozoan causing encephalitis in wild birds. We describe the clinical, pathological, and molecular aspects of an infection by S. falcatula in a bare-faced ibis (Phimosus infuscatus). Clinically, wing paralysis and mild motor incoordination were observed. At necropsy, the telencephalic cortex showed multifocal to coalescing yellowish soft areas. Histologically, multifocal to coalescent nonsuppurative necrotizing meningoencephalitis of telencephalic cortex, cerebellum, and brainstem was observed. Necrotic areas showed multiple protozoan organism characteristics of Sarcocystis sp. schizonts in the cytoplasm of endothelial cells or lying free in the neuropil. Partial genetic sequences of the gene encoding cytochrome b (CYTB), the gene encoding the beta subunit of RNA polymerase (RPOB) and the first internal transcribed spacer (ITS-1) from Sarcocystis sp. schizonts revealed that the parasite had ITS-1 sequences that were 100% identical to the homologous alleles from Sarcocystis sp. shed by Didelphis albiventris in Brazil. RPOB and CYTB sequences were 100% identical to homologous of S. falcatula available in Genbank. Thus, this is the first report of necrotizing meningoencephalitis caused by S. falcatula in bare-faced ibis (P. infuscatus).

Neurotuberculosis in cattle in southern Brazil.

Tuberculosis in cattle is a chronic infectious-contagious disease characterized by the development of nodular lesions (granulomas) in mainly the lungs and regional lymph nodes. It is caused by Mycobacterium tuberculosis complex, an acid-fast bacillus (AFB). Tuberculosis in the central nervous system is a rare condition in cattle. Herein, we describe the clinical and pathological findings of six neurotuberculosis cases in cattle diagnosed in Southern Brazil. The average age of the cattle affected was 12 months, and they varied in breed and sex. The clinical history ranged from 5 to 30 days and was characterized by motor incoordination, opisthotonus, blindness, and progression to recumbency. The cattle were euthanized, and grossly, the leptomeninges at the basilar brain showed marked and diffuse expansion, with nodular yellowish lesions ranging in size. On microscopic examination, there were multifocal granulomas located mainly in the meninges, though sometimes extending to adjacent neuropil or existing as isolated granulomas in neuropil. AFBs were observed in the cytoplasm of epithelioid macrophages and multinucleated giant cells through Ziehl-Neelsen histochemical staining and identified as Mycobacterium sp. through immunohistochemistry.

Pathology of Gastrointestinal Tuberculosis in Cattle.

We describe the pathology of gastrointestinal tuberculosis in three cows. Gross lesions were found in the jejunum and ileum in all cases, and were characterized by button-shaped ulcers in the mucosa overlying Peyer's patches and adjacent mucosa. One case had similar changes in the pyloric region of the abomasum. In the affected intestinal segments, marked granulomatous inflammation effaced the lymphoid follicles of Peyer's patches and often extended transmurally. Transmural granulomatous inflammation was also found in the abomasum of one cow. Acid-fast bacilli were identified by the Ziehl-Neelsen method and the lesions were immunolabelled by an anti-Mycobacterium tuberculosis complex antibody. M. tuberculosis var. bovis was isolated in one case. Disseminated tuberculosis and marked lung lesions in all cows suggested that the gastrointestinal lesions were most likely secondary to pulmonary infection.

Pathological and virological features of skin lesions caused by BVDV in cattle.

Dermatitis might occur in mucosal disease (MD) caused by bovine viral diarrhea virus (BVDV). This study describes the pathological and virological features of skin lesions associated with BVDV infection in four persistently infected (PI) cattle. Skin samples were reprocessed for histopathology and IHC. BVDV isolates were obtained and were genetically characterized. In addition to upper alimentary system ulcerative lesions, all cattle (one outbreak and three individual cases) presented focal crusty and ulcerative lesions affecting the mucocutaneous and skin-horn junctions, interdigital clefts, pastern, and areas surrounding the dewclaws and diffuse thickened skin within 7-20 days of infection. Microscopic analysis revealed parakeratotic hyperkeratosis and single-cell keratinocyte death, accompanied by ballooning degeneration and spongiosis in the epidermis, as well as intraepithelial and subcorneal pustules. IHC showed BVDV antigen in the cytoplasm of keratinocytes undergoing individual cell death. Phylogenetic analysis revealed that the isolates from cattle #1, #2, and #4 belonged to BVDV-1a, whereas that from cattle #3 belonged to BVDV-1d. Cytopathic BVDV was isolated from cattle #2 and #3 (MD), and non-cytopathic BVDV was isolated from cattle #1 and #4. Thus, BVDV infection might cause acute disease, characterized by skin and upper alimentary system ulcerative lesions, in both MD and PI cattle.

Mamastrovirus 5 detected in a crab-eating fox (Cerdocyon thous): Expanding wildlife host range of astroviruses.

Astroviruses are a common cause of gastroenteritis in children worldwide and can also cause infection in a range of domestic and wild animal species. Canine astrovirus (formally named as Mamastrovirus 5, MAstV5) has been reported worldwide, and its role as an enteric pathogen is still controversial. Herein, we describe the genomic characterization of a MAstV5 (strain crab-eating fox/2016/BRA) identified in a wild canid (Cerdocyon thous) diagnosed with canine distemper virus (CDV) as causa mortis. The nearly complete genome comprised 6579 nt in length and displayed the archetypal organization of astroviruses. The present report is the first evidence of MAstV5 infection in an animal species other than the dog and highlights a possible natural astrovirus spillover between domestic and wild canids. Moreover, these results show the first evidence of extra-intestinal MAstV5, suggesting a virus systemic spread. This work is expected to contribute to a better understanding of the astroviruses biology and their interactions with the wildlife health.

Cutaneous Pythiosis in calves: An epidemiologic, pathologic, serologic and molecular characterization.

This study reports the epidemiological, pathological and mycological findings of cutaneous pythiosis in cattle in southern Brazil. 23 calves, that were kept next to a river with extensive marshy regions, presented ulcerated cutaneous lesions in thoracic and pelvic limbs, sometimes extending to the ventral thoracic region. Histopathological examination revealed multifocal pyogranulomas in the superficial and deep dermis. The Grocott-Methenamine silver, immunohistochemistry anti-Pythium insidiosum, ELISA serology and molecular characterization demonstrated the agent P. insidiosum in these cases.

Characterization of spinal cord lesions in cattle and horses with rabies: the importance of correct sampling.

Twenty-six cattle and 7 horses were diagnosed with rabies. Samples of brain and spinal cord were processed for hematoxylin and eosin staining and immunohistochemistry (IHC). In addition, refrigerated fragments of brain and spinal cord were tested by direct fluorescent antibody test and intracerebral inoculation in mice. Statistical analyses and Fisher exact test were performed by commercial software. Histologic lesions were observed in the spinal cord in all of the cattle and horses. Inflammatory lesions in horses were moderate at the thoracic, lumbar, and sacral levels, and marked at the lumbar enlargement level. Gitter cells were present in large numbers in the lumbar enlargement region. IHC staining intensity ranged from moderate to strong. Inflammatory lesions in cattle were moderate in all spinal cord sections, and gitter cells were present in small numbers. IHC staining intensity was strong in all spinal cord sections. Only 2 horses exhibited lesions in the brain, which were located mainly in the obex and cerebellum; different from that observed in cattle, which had lesions in 25 cases. Fisher exact test showed that the odds of detecting lesions caused by rabies in horses are 3.5 times higher when spinal cord sections are analyzed, as compared to analysis of brain samples alone.

Timpanismo em bovinos, secundário à obstrução esofágica por citrus limon (limão siciliano) / Bloat in cattle secondary to esophageal obstruction by citrus limon (sicilian lemon)

Timpanismo ruminal consiste na distensão acentuada do rúmen e retículo, devido a incapacidade do animal em expulsar gases produzidos durante o processo fisiológico da fermentação. O timpanismo pode ser ocasionado de forma primária, por formação de espuma estável, ou secundária, devido a anormalidades funcionais e/ou físicas que interferem na eructação. Nesse trabalho, são descritos os aspectos epidemiológicos, clínicos e anatomopatológicos da ocorrência de timpanismo secundário em bovinos, decorrente da obstrução esofágica aguda por limões sicilianos. Cinco bovinos, de um lote de 210, foram afetados. Os bovinos eram suplementados com resíduo de tangerina (Citrus reticulata) no cocho e na última carga desse subproduto, havia limões sicilianos inteiros misturados ao resíduo. Os cinco animais afetados eram da raça Aberdeen Angus e tinham entre 12-24 meses de idade. Todos apresentaram sinais clínicos caracterizados principalmente por mucosas cianóticas, grave timpanismo, desconforto abdominal, acentuada dispneia e taquicardia, atonia ruminal, desidratação, decúbito e morte. O curso clínico variou entre 24 a 48 horas. Na necropsia, os cinco bovinos apresentavam grave obstrução esofágica por limões nas porções: cranial (logo após a laringe [1/5]), porção medial (entrada do tórax [1/5]) e final (próximo ao cárdia [3/5]). Nas áreas de oclusão, observou-se extensa necrose e ulceração da mucosa esofágica. O conteúdo ruminal dos bovinos estava seco e misturado com limões inteiros. No esôfago de dois animais havia linha de timpanismo. As lesões histológicas eram visualizadas principalmente no esôfago, na região da obstrução, onde se evidenciaram alterações degenerativas, necróticas e ulcerativas acentuadas no revestimento epitelial.

Ruminal bloat (acute timpany) in ruminants is a marked rumen-reticular distension which results from more gas being produced during the physiologic process of fermentation than is eliminated by eructation. This condition may present itself as either primary timpany due to the formation of stable foam or secondary timpany resulting from functional and/or physical disturbances compromising eructation. This paper describes the epidemiological, clinical, and anatomopathological aspects of acute timpany in cattle secondary to esophageal obstruction by sicilian lemons. Five out of a herd of 210 cattle were affected. Cattle were supplemented with tangerine (Citrus reticulata) residues in a trough. In the last batch of this feed there were whole sicilian lemons mixed with the tangerine residue. The five affected cattle were 12-24 month-old Aberdeen-Angus. All of the five presented clinical signs characterized mainly by cyanotic mucous membranes, severe timpany, abdominal discomfort, marked dyspnea and tachycardia, ruminal atony, dehydration, recumbence and death. Clinical course lasted from 24 to 48 hours. Necropsy findings in the five affected cattle were similar and included complete esophageal obstruction by lemons in the cranial esophagus (immediately cranial to the larynx [1/5]) medial esophagus (at the thoracic inlet [1/5]) and caudal esophagus (close to the cardia [3/5]). At the occluded sites the esophageal mucosa was necrotic and ulcerated. Ruminal content was dried and admixed with whole lemons. In the esophagus o two affected bovine a bloat line was observed. Histological lesions were observed mainly in the esophagus at the sites of obstruction and consisted of marked degenerative, necrotic and ulcerative changes in the esophageal mucosal epithelium.

Características e frequência das doenças de suínos na Região Central do Rio Grande do Sul / Characteristics and frequency of diseases in pigs from the central Rio Grande do Sul State, Brazil

Visando-se determinar as características e frequência das doenças na população suína na região de abrangência do Laboratório de Patologia Veterinária (LPV) da Universidade Federal de Santa Maria (UFSM), foi realizado um estudo retrospectivo de todos os diagnósticos de necropsias realizadas nesta espécie no período de 1964 a 2011. Foram separados 564 casos com diagnósticos conclusivos. A criação suína na região de abrangência do estudo é predominantemente familiar e as doenças diagnosticadas, refletem esta realidade. As doenças infecciosas e parasitárias foram as mais prevalentes [380(68,1%)], seguidas, em ordem decrescente, das doenças metabólicas e nutricionais [64(11,5%)], intoxicações e toxi-infecções [33(5,9%)], e distúrbios do desenvolvimento [15(2,7%)]. Outras alterações de diversas etiologias, sobretudo de trauma, foram causa de morte em pouco mais de 11% dos protocolos examinados. Doenças bacterianas foram responsáveis por mais da metade das causas de morte ou razão para eutanásia dos suínos estudados, revelando a influência de fatores de manejo, ambientais e nutricionais regional de criação de suínos. A principal doença diagnosticada em suínos na região de abrangência do estudo foi a doença do edema e juntamente com outras formas de infecção por Escherichia coli é responsável por 23% das mortes. Doenças de etiologia viral e neoplasia não são importantes causas de morte em suínos na região estudada. Hepatose nutricional e aflatoxicose são importantes doenças da região e se devem, sobretudo, a fatores de manejo nutricional.

A retrospective study of all necropsy performed in pigs in the Laboratório de Patologia Veterinária (LPV) at Universidade Federal de Santa Maria (UFSM) was carried out in order to determine the characteristics and frequency of diseases in the swine population raised in the region the region covered by the activities of LPV. Five hundred and four cases with conclusive diagnosis were found. The type of pig-raising in the area is mainly a familiar enterprise and the diseases found in this survey reflect this reality Infectious and parasitic diseases were the most prevalent [380(68.1%)], followed, in descending order of frequency, by nutritional and metabolic diseases [64(11.5%)], poisonings and toxi-infections and development disorders [15(2.7%)]. Other disorders due to varying etiologies, especially trauma, were cause of death in just over 11% of the cases. Bacterial diseases were responsible for more than half of the causes of death in pigs of the studied population, pointing to the influence of management, environmental and nutritional regional husbandry. The moist frequent disease diagnosed in pigs in the region in the region covered by the study was edema disease which along with other forms of infection by Escherichia coli was responsible for 23% of deaths. Viral diseases and neoplasm were not major causes of death in pigs in the region studied. Nutritional hepatosis and aflatoxicosis are important diseases in pigs in this region and and there causation are mainly linked to nutritional management.