Toxigenic characterization, spoilage potential, and antimicrobial susceptibility of coagulase-positive Staphylococcus species isolated from Minas Frescal cheese.

This study aimed to identify coagulase-positive staphylococci (CPS) species from 21 samples of clandestine Minas Frescal cheese, investigate the potential for deterioration in psychrotrophic and mesophilic conditions, verify the toxigenic potential of Staphylococcus aureus, and determine the antimicrobial susceptibility profile of toxigenic S. aureus. Species determination was performed based on the detection of ß-hemolysis in 5% ovine blood agar; fermentation of mannitol, maltose, and trehalose sugars; and production of acetoin. After species determination, DNA extraction and analysis was performed for S. aureus colonies for genes encoding staphylococcal toxins (eta, etb, tst, sea, seb, sec, sed, and see) using 2 multiplex PCR assays. Isolates identified as toxigenic S. aureus were tested for antimicrobial susceptibility to tetracycline, erythromycin, clindamycin, gentamicin, ciprofloxacin, sulfazotrim, trimethoprim, streptomycin, cefoxitin, vancomycin and enrofloxacin. Elevated CPS counts were observed with an average of >6 log cfu/g. Of the 355 isolates, 177 (49.86%) were identified as S. aureus. Staphylococcus hyicus, Staphylococcus intermedius, Staphylococcus delphini, and Staphylococcus coagulans were identified in 3 (0.84%), 2 (0.56%), 2 (0.56%), and 1 (0.28%) isolates, respectively. Of the total number of S. aureus, 25 (52.08%) were positive for the gene that encodes for toxic shock toxin (TSST-1). Another 16 (33.33%) were positive for the sea gene, and 4 isolates (8.33%) were positive for see and one isolate each was positive for seb (2.08%), sec (2.08%), and etb (2.08%) genes. All isolates demonstrated lipolytic activity under mesophilic and psychrotrophic conditions. S. intermedius and S. hyicus had the most prominent proteolytic potential. Multidrug resistance was observed in most of the potentially toxigenic isolates, with clindamycin having the lowest efficiency (40%), whereas the aminoglycosides (gentamicin and streptomycin) had the highest effectiveness demonstrating inhibition in all evaluated isolates. Methicillin-resistant S. aureus (MRSA) was detected. Minas Frescal cheeses, marketed in the north of Tocantins in the Brazilian Amazon region, do not comply with legal quality standards and pose a public health risk due to the enterotoxigenic potential of multiresistant isolates, in addition to low shelf life of the samples given the high spoilage potential of this microbiota.

Effect of milk bactofugation on the counts and diversity of thermoduric bacteria.

The objective of this work was to determine the effect of milk bactofugation on the counts and microbial diversity of mesophilic (MT), psychrotrophic (PT), and thermophilic (TT) thermoduric bacteria and its potential as a technological method to remove spoilage microorganisms resistant to pasteurization. Different batches of raw milk from 69 dairy farms divided into sets in 3 bulk tanks (A, B, C) were evaluated at different times during the technological process. As the raw milk was preheated (∼55°C) immediately before bactofugation (10,000 × g), the effect of bactofugation was estimated by comparing the counts in raw, preheated, and bactofuged milk. This centrifugation was sufficient to reduce the isolation of 88% of the MT in preheated milk. For PT, it was possible to verify a reduction of 72.5% in batch C. The TT were not recovered at higher detection limits (<5 cfu/mL). For diversity, 310 isolates were identified using a molecular approach; 15 species of contaminating thermoduric bacteria were identified from raw and preheated milk, and only 6 species were recovered in bactofuged milk. Only MT were recovered from the bactofuged milk, mainly the species Lysinibacillus fusiformis (61.7%) and Bacillus licheniformis (12.3%). Both species are known to be endospore-forming psychrotrophs and have proteolytic or lipolytic activity. The bactofugation of raw milk reduced the number of isolates of B. licheniformis, Bacillus toyonensis, Micrococcus aloeverae, and Aestuariimicrobium kwangyangense by 33, 43, 86, and 92%, respectively, and reduced the isolates of Macrococcus caseolyticus, Lysinibacillus varians, Carnobacterium divergens, Microbacterium hominis, Kocuria indica, Micrococcus yunnanensis, Gordonia paraffinivorans, Bacillus invictae, and Kocuria kristinae to undetectable levels. The results of this study indicate that bactofugation can be applied by the dairy industry to reduce pasteurization-resistant microorganisms in combination with prophylactic measures to prevent the contamination of raw milk by spores and vegetative forms of bacteria.

Immunohistochemical Detection of Intralesional Antigens of Ovine Gammaherpesvirus-2 in Cattle with Sheep-associated Malignant Catarrhal Fever.

Sheep-associated malignant catarrhal fever (SA-MCF) is a severe lymphoproliferative disease of ruminants caused by ovine gammaherpesvirus-2 (OvHV-2). Since the initial identification of SA-MCF there has been extensive research related to the pathogenesis of OvHV-2, based primarily on serological and molecular assays associated with typical histopathological findings. The monoclonal antibody (MAb-15A) binds to a common epitope in MCF viruses and is used frequently in serological investigations. However, the utilization of this antibody to detect antigens of OvHV-2 in tissues has not been examined. Accordingly, this study standardized an immunohistochemical assay using MAb-15A to identify antigens of OvHV-2 in tissues of cattle (n = 5) with SA-MCF. All animals developed acute neurological signs, without ocular and nasal manifestations, and had nucleic acids of OvHV-2 in brain tissue detected by polymerase chain reaction. The principal histopathological findings were lymphocytic nephritis (n = 5), widespread arterial proliferation and vasculitis (n = 5), lymphocytic portal hepatitis (n = 3), non-suppurative meningoencephalitis (n = 2) and atrophic enteritis with cryptal necrosis and dilation (n = 2). Intralesional intracytoplasmic antigens of OvHV-2 were identified within multiple epithelial cells of the kidneys of all animals, the intestines of animals with and without atrophic enteritis, and within epithelial cells of bile ducts in animals with lymphocytic hepatitis. Additionally, there was positive intracytoplasmic immunoreactivity within histiocytes and lymphocytes in several tissues. These findings suggest that the MAb-15A detects antigens of OvHV-2 within epithelial cells and leucocytes in several organs. Moreover, this assay would contribute significantly towards understanding of the pathogenesis of SA-MCF and may be used for retrospective studies. Additionally, angiopathy in SA-MCF may be a progressive lesion, which may terminate in luminal occlusion and probably occurs irrespectively of the eye and head form of MCF.

Short communication: Molecular characterization and antimicrobial resistance of pathogenic Escherichia coli isolated from raw milk and Minas Frescal cheeses in Brazil.

The aim of this study was to quantify, identify, evaluate antimicrobial resistance, and characterize the virulence factors of enteropathogenic (EPEC), Shiga-toxigenic (STEC), and enterohemorrhagic (EHEC) Escherichia coli in raw milk (RM) and legal (LMFC) and illegal (IMFC) Minas Frescal cheeses in southern and northeast Brazil. Illegal cheeses are those made without official inspection service or sanitary surveillance. We evaluated samples of RM produced in Paraná (southern) and Maranhão (northeast) States, LMFC produced using pasteurized milk in inspected industries, and IMFC potentially produced with raw milk. Mean total coliform counts were 8.4 × 104 cfu/mL for RM, 1.4 × 107 cfu/mL for LMFC, and 2.9 × 107 cfu/mL for IMFC. Mean E. coli counts were 2.4 × 103 cfu/mL for RM, 1.9 × 102 cfu/mL for LMFC, and 1.1 × 105 cfu/mL for IMFC. Among the 205 E. coli isolates from RM, 9.75% were identified as EPEC, mainly (90%) in samples from Paraná. Of the total isolates from the cheese samples, 97.4% (n = 111) came from IMFC, of which 1.8 and 2.7% were identified as EPEC and STEC, respectively; no EHEC was detected. The phylogenetic group A (60%) and typical EPEC (68%) predominated, which confirms the possible human origin of pathogenic isolates in RM and IMFC. Of these, 50% were resistant to at least one antibiotic, and streptomycin was the antimicrobial with the highest number (8) of EPEC and STEC resistant isolates. This study reports the first isolation of serogroup O28ac in Brazilian milk. We found no predominance of a specific serogroup of EPEC or STEC in milk or cheese or clonal isolates in the same sample, indicating different origins of the contamination in these products, presumably mostly related to poor hygienic handling.

Fatores de risco associados à infecção viral (BoHV-1 e BVDV) em rebanhos leiteiros mestiços com problemas reprodutivos, no município de Uberlândia, MG / Risk factors associated with viral infections (BoHV-1 and BVDV) in crossbreed dairy herds with reproductive failures, Uberlândia, MG

Com frequência, infecções virais são associadas a problemas da reprodução em rebanhos de bovinos de corte e leite de todo o mundo. Este estudo teve como objetivo avaliar variáveis de manejo que possam constituir fatores de risco da infecção por BoHV-1 e/ou por BVDV em rebanhos leiteiros com histórico de problemas da reprodução em vacas mestiças em manejo extensivo e sem histórico de vacinação prévia para o controle de IBR e BVD. Anticorpos neutralizantes anti-BoHV-1, anti-BVDV e para ambos os vírus simultaneamente foram identificados em 62,5% (165/264), 45,1% (119/264) e 31,4% (83/264), respectivamente, das amostras analisadas. Os fatores de risco associados à infecção por BoHV-1 foram rebanhos com número total de fêmeas superior a 100, presença de ordenha mecânica, não utilização de inseminação artificial na reprodução e a compra infrequente de animais. Para BVDV, os fatores de risco foram aptidão mista (leite/corte) do rebanho, presença de ordenha mecânica, ausência de quarentena para os animais recém-adquiridos, presença de piquete de parição e a não utilização de inseminação artificial. Para a infecção simultânea (BoHV-1/BVDV), a presença de ordenha mecânica aumentou o risco em 3,36 vezes, e o uso de inseminação artificial reduziu em 56% o risco de infecção nos rebanhos avaliados.(AU)

Viral infections are frequently associated with reproductive problems in dairy and beef cattle worldwide. The aim of this study was to verify managerial practices that may constitute risk factors associated with infection by BoHV-1 and/or BVDV in dairy herds with a history of reproductive disease in extensively reared dairy cows without a previous history of vaccination against IBR and BVD. Neutralizing antibodies anti-BoHV-1, anti-BVDV or both were detected in 62.5% (165/264), 45.1% (119/264), and 31.4% (83/264), respectively, in the samples analyzed. The risk factors associated with infection by BoHV-1 were herds with more than 100 cows, the presence of mechanical milking, the non-utilization of artificial insemination, and the infrequent acquisition of animals. Risk factors associated with BVDV were dual-purpose herds (milk and beef), these include the utilization of mechanical milking, absence of quarantine for newly acquired animals, the presence of picket calving, and the absence of artificial insemination. For simultaneous infections by both viruses (BoHV-1 and BVDV) the use of mechanical milking increased the chance of infection 3.36-fold while the use of artificial insemination reduced the risk of infection by 56% in these herds.(AU)

Non-toxigenic strain of Clostridioides difficile Z31 reduces the occurrence of C. difficile infection (CDI) in one-day-old piglets on a commercial pig farm.

Neonatal porcine diarrhea (NPD) is a current problem on pig farms and is caused by several enteropathogens. Among them, Clostridioides difficile stands out due to its importance in piglets and zoonotic potential. A non-toxigenic strain of C. difficile (NTCD), named Z31, was previously tested in hamster and piglet experimental models as a strategy to prevent C. difficile infection (CDI). To evaluate the capacity of the strain Z31 to prevent CDI and NPD in one-day-old piglets on a commercial farm, 90 piglets from 16 litters received 1 × 106 spores of Z31 while 84 animals from the same litters served as controls. Animals were clinically evaluated, and fecal samples were collected 24 h after administration and submitted to A/B toxin detection and isolation of C. difficile. Stool samples were also submitted to rotavirus, Escherichia coli, and Clostridium perfringens detection. Administration of Z31 reduced the incidence of CDI in treated animals (7.8%) when compared to the control group (25.0%; P = 0.003). In animals that developed CDI, the intensity of diarrhea was lower in those that received Z31 than in the control group. Neonatal porcine diarrhea was reduced in treated animals when compared to untreated animals (P < 0.001). The present study suggests that Z31 can potentially be used to prevent CDI in piglets on commercial farms.

Helicobacter infection in the hepatobiliary system and hepatic lesions: a possible association in dogs.

Helicobacter infection has been associated with hepatobiliary diseases in humans and animals. The aims of this study were to identify Helicobacter species in the hepatobiliary tract of dogs and to elucidate the possible association of these bacteria in liver diseases. Twenty-seven gastric and hepatobiliary samples were collected from 33 dogs with hepatic lesions and 17 dogs with no liver histological changes. Warthin-Starry staining, immunohistochemical assay, and PCR were performed to detect the presence of Helicobacter. Helicobacter genus was detected in 21.2% of the samples with hepatic lesions. The main lesion was chronic hepatitis. Immunohistochemistry revealed infection in liver (1/5) and gallbladder (1/3) 32 samples. The sequence analysis of seven amplicons of the 16S rRNA gene of Helicobacter genus from hepatobiliary samples showed 97.8 to 100% of nucleotide identity with gastric helicobacter. One amplicon of the ureA and ureB gene of Helicobacter genus from the stomach showed 89.1 to 90.7% nucleotide identity with H. heilmannii. The presence of Helicobacter genus in liver samples showing hepatic lesions suggests the involvement of these bacteria in the etiology of hepatobiliary disease in dogs. DNA sequences were similar to gastric Helicobacter species, reinforcing the hypothesis of bacterial translocation from the stomach to liver by the biliary pathway.

Carcass characteristics and meat quality of broilers fed with different levels of Saccharomyces cerevisiae fermentation product.

Fermented products and components of Saccharomyces cerevisiae have been widely used in animal nutrition to promote the development and quality of broilers. This study aims to evaluate different levels of inclusion (0, 250, 750, 1,500 g/t) of S. cerevisiae fermentation product (SCFP) in broiler feed to gauge its effect on carcass characteristics and cuts beyond the quality of breast meat. For analyses of carcass yield, cuts, and meat quality, 16 broilers per treatment were slaughtered. The meat quality analyses were performed 24 h after slaughter and evaluated color, pH, water holding capacity, cooking loss, and shear force. Lipid oxidation was determined in frozen breast samples stored at -20°C for 45 d. The results indicate that different levels of inclusion of SCFP provided no changes in carcass yield, color, water holding capacity, cooking loss, and shear force; however, inclusion of 1,500 g/t of SCFP increased leg yield and reduced pH. The inclusion of 750 g/t of SCFP decreased the lipid oxidation of breast meat (P < 0.05). This study concluded that inclusion of SCFP may improve leg yield and the lipid oxidation of breast meat.

Genetic diversity of thermoduric spoilage microorganisms of milk from Brazilian dairy farms.

When correctly pasteurized, packaged, and stored, milk with low total bacterial counts (TBC) has a longer shelf life. Therefore, microorganisms that resist heat treatments are especially important in the deterioration of pasteurized milk and in its shelf life. The aim of this work was to quantify the thermoduric microorganisms after the pasteurization of refrigerated raw milk samples with low TBC and to identify the diversity of these isolates with proteolytic or lipolytic potential by RFLP analysis. Twenty samples of raw milk were collected in bulk milk tanks shortly after milking in different Brazilian dairy farms and pasteurized. The mean thermoduric count was 3.2 (±4.7) × 102 cfu/mL (2.1% of the TBC). Of the 310 colonies obtained, 44.2% showed milk spoilage potential, 32.6% were proteolytic and lipolytic simultaneously, 31% were exclusively proteolytic, and 48 (36.4%) were only lipolytic. Regarding the diversity, 8 genera were observed (Bacillus, Brachybacterium, Enterococcus, Streptococcus, Micrococcus, Kocuria, Paenibacillus, and Macrococcus); there was a predominance of endospore-forming bacteria (50%), and Bacillus licheniformis was the most common (34.1%) species. Considering the RFLP types, it was observed that the possible clonal populations make up the microbiota of different milk samples, but the same milk samples contain microorganisms of a single species with different RFLP types. Thus, even in milk with a high microbiological quality, it is necessary to control the potential milk-deteriorating thermoduric microorganisms to avoid the risk of compromising the shelf life and technological potential of pasteurized milk.

Papillomaviruses in ruminants: An update.

Papillomaviruses (PVs) are complex viruses which infect the skin or mucosae of a broad range of amniotes worldwide. They cause benign or malignant lesions depending on environmental factors, virus oncogenicity and the location of infection. Bovine papillomaviruses (BPVs) are the second most studied PVs beyond human PVs. In the past few years, genetic characterization of animal PVs has increased due to the availability of new techniques, which simplified the sequencing of entire genomes. Therefore, this review aims to provide an update of the current epidemiology, classification and genome features of ruminant PVs (mainly BPVs) affecting animals worldwide. The review also aimed to clarify the key differences between the high-risk Delta papillomaviruses and the seemingly low-risk Xi, Epsilon, Dyoxi and Dyokappapillomavirus as well as the recently described PVs BPV18, 19, 21 and PpuPV1 that belongs to an unclassified genus.

Viruses associated with congenital tremor and high lethality in piglets.

The recently described atypical porcine pestivirus (APPV) has been associated with congenital tremor (CT) type A-II in piglets in different countries. Another important neurological pathogen of pigs is porcine teschovirus (PTV), which has been associated with non-suppurative encephalomyelitis in pigs with severe or mild neurological disorders. There have been no reports of APPV and/or PTV coinfection associated with CT or encephalomyelitis in Brazilian pig herds. The aim of this study was to describe the pathological and molecular findings associated with simultaneous infection of APPV and PTV in piglets with clinical manifestations of CT that were derived from a herd with high rates of CT-associated lethality. In 2017, three piglets from the same litter with CT died spontaneously. The principal pathological alterations in all piglets were secondary demyelination and hypomyelination at the cerebellum, brainstem and spinal cord confirmed by histopathology and luxol fast blue-cresyl violet stain. Additional significant pathological findings included multifocal neuronal necrosis, neuronophagia and gliosis found in the cerebral cortex and spinal cord of all piglets, while atrophic enteritis and mesocolonic oedema were observed in some of them. APPV and PTV RNA were detected in the central nervous system of affected piglets, and PTV was also detected in the intestine and faeces. The pathological alterations and molecular findings together suggest a dual infection due to APPV and PTV at this farm. Moreover, the combined effects of these pathogens can be attributed to the elevated piglet mortality, as coinfections involving PTV have a synergistic effect on the affected animals.

High-resolution phylogeny providing insights towards the epidemiology, zoonotic aspects and taxonomy of sapoviruses.

The evolution, epidemiology and zoonotic aspects of Sapoviruses (SaV) are still not well explored. In this study, we applied high-resolution phylogeny to investigate the epidemiological and zoonotic origins as well as taxonomic classification of animal and human SaV. Bayesian framework analyses showed an increase in porcine SaV (PoSaV) population dynamics and genetic diversity between 1975 and 1982, resulting in a SaV gene flow and generation of new strains among porcine and human populations. Our results also show the contribution of different animal populations involved in SaV epidemiology and highlight zoonotic aspects, as exemplified by the crucial role that swine, dogs, mink and humans play in SaV spread. Additionally, phylogenetic analysis suggests that bats may play key role in SaV epidemiology. According to our hypothesis, these animals may act as reservoirs or intermediate host species, contributing to viral spread in zoonotic and other epidemiological scenarios and facilitating the generation of new SaV genogroups and genotypes through recombination events. Data from large-scale phylogeny partition based on patristic distance, did not show a correlation between transmission clusters on generation of SaV genogroups, nevertheless we present both important findings about SaV taxonomy and important considerations useful for further taxonomical studies.

Pneumonia due to Talaromyces marneffei in a Dog from Southern Brazil with Concomitant Canine Distemper Virus Infection.

The pathological and molecular findings associated with Talaromyces marneffei-induced pneumonia with concomitant infection by canine distemper virus (CDV) are described in a dog. The principal pathological alteration occurred in the lungs. Histopathology confirmed multifocal granulomatous pneumonia associated with numerous intralesional and intracellular septate fission cells consistent with T. marneffei. A molecular assay designed to amplify a partial fragment of the 18S rRNA gene of T. marneffei provided positive results from two fungal cultures derived from the lung. Sequencing and phylogenetic analyses confirmed the results of polymerase chain reaction (PCR). Furthermore, antigens of the CDV N protein were identified within the bronchial epithelium by immunohistochemistry and a PCR assay amplified the CDV N gene from hepatic and pulmonary fragments. Collectively, the pathological and molecular techniques confirmed a diagnosis of T. marneffei-induced pneumonia with concomitant infection by CDV. These findings represent the first description of pulmonary penicilliosis in the dog and extend the geographical niche of this emerging infectious pathogen. In this case, infection by CDV may have induced immunosuppression, which facilitated the development of pulmonary penicilliosis.

Brazilian strain of bovine respiratory coronavirus is derived from dual enteric and respiratory tropism.

Bovine coronavirus (BCoV) is a pathogen related to enteric and respiratory diseases in cattle worldwide. Enteric (BECoV) strains of BCoV are predominant in South America, and genetic investigations have been conducted to identify its relationship with isolates of respiratory origin (BRCoV). In this study, we used a BRCoV strain (BR-UEL11) derived from an outbreak of respiratory disease in feedlot cattle in southern Brazil, and compared the partial sequence of the polymorphic region of Spike (which was detected and sequenced by two distinct reverse transcription-polymerase chain reactions) with those of other BCoV strains. The phylogenetic relationship of BR-UEL11 with Brazilian BCoV, which is associated with calf diarrhea and winter dysentery (enteric, BECoV; respiratory, BRCoV), and classical reference prototypes was analyzed. The analysis showed that the BRCoV strains from Brazil clustered with a clade that was distinct from most isolates associated with calf diarrhea (BECoV) and ancestral prototype strains such as Mebus, Nebraska, and LYVB. Furthermore, the BRCoV strains from Brazil clustered with a clade that contained recent strains associated with winter dysentery, showing 98-99% nucleotide identity with those strains. These results suggested that the Brazilian BCoV evolved from being solely enteric to a dual enteric and respiratory tropic virus.

Effect of propolis ethanol extract on myostatin gene expression and muscle morphometry of Nile tilapia in net cages.

Propolis can be used as growth enhancer due to its antimicrobial, antioxidant, and immune-stimulant properties, but its effects on morphometry and muscle gene expression are largely unknown. The present study evaluates the influence of propolis on muscle morphometry and myostatin gene expression in Nile tilapia (Oreochromis niloticus) bred in net cages. Reversed males (GIFT strain) with an initial weight of 170 ± 25 g were distributed in a (2 x 4) factorial scheme, with two diets (DPRO, commercial diet with 4% propolis ethanol extract and DCON, commercial diet without propolis, control) and four assessment periods (0, 35, 70, and 105 experimental days). Muscles were evaluated at each assessment period. Histomorphometric analysis classified the fiber diameters into four groups: <20 µm; 20-30 µm; 30-50 µm; and > 50 µm. RT-qPCR was performed to assess myostatin gene expression. Fibers < 20 µm diameter were more frequent in DPRO than in DCON at all times. Fiber percentages >30 µm (30-50 and > 50 µm) at 70 days were 25.39% and 40.07% for DPRO and DCON, respectively. There was greater myostatin gene expression at 105 days, averaging 1.93 and 1.89 for DCON and DPRO, respectively, with no significant difference in any of the analyzed periods. Propolis ethanol extract did not affect the diameter of muscle fibers or the gene expression of myostatin. Future studies should describe the mechanisms of natural products' effects on muscle growth and development since these factors are highly relevant for fish production performance.

Morphology and muscle gene expression in GIFT and Supreme Nile tilapia varieties reared in two cultivation systems.

Tissue growth in most fishes occurs by muscular hyperplasia and hypertrophy, which are influenced by different regulatory factors, such as myostatin. The current study evaluated the influence of cultivation in hapas and earthen ponds on the diameter of white muscle fibers and on the myostatin (MSTN-1) gene in GIFT and Supreme varieties of tilapia. Fish of both varieties were reared for 204 days and then divided into four developmental stages. White muscle samples, corresponding to 100 fibers per slide, were collected from the middle region of fish of each variety and cultivation system, and were measured and divided into two classes representing hyperplasia and hypertrophy. Samples were subjected to real-time PCR to analyze gene expression. Hyperplasia decreased during the developing stages, coupled with increased hypertrophy. There was a higher rate of hypertrophy in fish raised in earthen ponds when compared to those raised in hapas, during juvenile and developing phases, and greater hypertrophic growth was observed in GIFT specimens when compared to Supreme specimens in earthen ponds. Since increased MSTN-1 gene expression was observed in GIFT specimens during the developing phase in pond cultivations, and in Supreme tilapia in hapas, MSTN-1 expression is related to greater hypertrophy. These results demonstrate the capacity for increased muscle growth in earthen pond cultivation in which the GIFT variety developed best. How the environment affects the growth of different tilapia varieties may be employed to optimize culture management and genetic improvement programs. Further investigations should aim to describe mechanisms affecting muscle growth and development.

Retrospective study of Bovine herpesvirus 5 meningoencephalitis in cattle from São Paulo State, Brazil / Estudo retrospectivo de meningoencefalite por herpesvírus bovino-5 em bovinos do estado de São Paulo, Brasil

Meningoencephalitis caused by Bovine herpesvirus 5 (BoHV-5) is an important neurological disease that affects Brazilian cattle herds. The present study investigated the presence of BoHV-5 DNA in cattle diagnosed with meningoencephalitis at Faculdade de Medicina Veterinária e Zootecnia, UNESP - Univ Estadual Paulista from 1980 to 2009. The records obtained from the Large Animal Internal Medicine Service and the Animal Pathology Service were reviewed to identify clinical and epidemiological data from cattle with neurological signs. Excluding rabies cases, we found 115 cases of cattle with neurological signs that had been necropsied. Non-suppurative meningoencephalitis was diagnosed in 28 animals of the 115 initially selected based on histopathological examination of brain tissues. Of these 28 animals, 15 (54%) were positive for BoHV-5 DNA by polymerase chain reaction (PCR) of formalin-fixed paraffin-embedded (FFPE) brain samples. PCR target was 159-bp fragment from the BoHV-5 glycoprotein C gene. The oldest case identified in the present study was from 1988. PCR was a good tool for the diagnosis of BoHV-5 DNA extracted from FFPE tissues, allowing retrospective studies of samples stored for more than 20 years.(AU)

A meningoencefalite por herpesvírus bovino-5 (BoHV-5) é uma doença neurológica importante no rebanho bovino brasileiro. Este estudo tem por objetivo verificar a presença do DNA de BoHV-5 em bovinos diagnosticados com meningoencefalite na Faculdade de Medicina Veterinária e Zootecnia da Universidade Estadual Paulista, entre os anos de 1980 e 2009. Foram revisados os arquivos do Serviço de Clínica de Grandes Animais e da Patologia Animal em busca dos dados clínicos e epidemiológicos de bovinos com sinais neurológicos. Excluídos os casos de raiva, foram encontrados 115 casos de bovinos com sinais neurológicos, que foram necropsiados. O exame histopatológico realizado nos tecidos encefálicos desses animais constatou lesões de meningoencefalite não supurativa em 28 animais. Destes, em 15 (54%) casos foi identificada a presença do DNA de BoHV-5 por meio de PCR realizada em amostras de tecido encefálico fixadas em formalina e incluídas em parafina (FFPE). O alvo da PCR foi um fragmento de 159 pb do gene da glicoproteína C do BoHV-5. O caso mais antigo identificado neste estudo foi de 1988. A PCR apresentou-se como boa ferramenta para o diagnóstico do DNA de BoHV-5 extraído de tecidos FFPE, possibilitando estudos retrospectivos e diagnóstico de amostras com mais de 20 anos de armazenamento.(AU)

Pyogenic Ventriculitis and Ventricular Empyema associated with Staphylococcus pseudintermedius in a Puppy.

A 40-day-old male, blue heeler puppy with hindlimb ataxia, nystagmus, apathy, motor incoordination and hyperaesthesia of the forelimbs died 3 days after the onset of clinical signs. Significant gross findings included cerebellar herniation, cerebral oedema and dilation of the third and right lateral cerebral ventricles due to the accumulation of a purulent exudate. Histopathological examination revealed pyogenic ventriculitis and purulent meningoencephalitis. Pure colonies of a coagulase-positive Staphylococcus were isolated from the purulent cerebral exudate. A polymerase chain reaction assay that targeted the 16S rRNA gene of bacteria amplified the desired product from bacterial colonies. Direct sequencing revealed the organism to be Staphylococcus pseudintermedius. Phylogenetic analyses showed that the organism was antigenically similar to Staphylococcus intermedius and Staphylococcus delphini, being part of the S. intermedius group of bacteria. These findings confirmed the participation of S. pseudintermedius in the development of the pathological manifestations and lesions observed in this puppy.

Pathological, Immunohistochemical and Molecular Findings Associated with Senecavirus A-Induced Lesions in Neonatal Piglets.

This study investigated the cause of the mortality of piglets with cutaneous, enteric and neurological disorders from seven pig farms located in different geographical regions of Brazil. Twelve 1- to 5-day-old piglets were submitted for pathological evaluation. The principal gross findings included faint rib impressions on the pleural surface of the lungs (n = 9), diphtheritic glossitis (n = 6) and ulcerative lesions at the coronary band (n = 5). Histopathology revealed interstitial pneumonia (n = 12), myocarditis (n = 6), diphtheritic glossitis (n = 3), encephalitis (n = 3) and atrophy of intestinal villi with vacuolation of the superficial epithelial cells (n = 6). Immunohistochemistry with monoclonal antibodies specific for Senecavirus A (SenV-A) demonstrated immunoreactivity of the choroid plexus of the cerebrum, degenerate epithelium of ulcerative lesions of the tongue, the urothelium of the kidney and urinary bladder, and the superficial cells of the intestine. Reverse transcriptase polymerase chain reaction (PCR), PCR and/or quantitative PCR assays were used to investigate viral agents associated with vesicular and/or enteric diseases. Antigens and RNA of SenV-A were identified in multiple tissues of all piglets; molecular assays for all other viruses evaluated yielded negative results. These findings confirm the participation of SenV-A in the multiple lesions observed in these piglets. Several theories are proposed: SenV-A may be eliminated via the urinary system, neurological disease may occur due to initial invasion of choroid plexus, enteric disease may be related to atrophy and fusion of villi of the small intestine, and vertical transmission could be a form of dissemination.

Presença do genoma de BoHV-5 no líquido cefalorraquidiano de bovinos com meningoencefalite herpética / Presence of BoHV-5 genome in cerebrospinal fluid of cattle with herpetic meningoencephalitis

The diagnosis of bovine herpesvirus 5 (BoHV-5) encephalitis is confirmed after death by laboratory methods applied to brain fragments. Alternative methods to confirm ante-mortem diagnosis are important because the disease is not always lethal. The aim of this study was to investigate whether the presence of the virus genome in the cerebrospinal fluid (CSF) detected by polymerase chain reaction (PCR) might be admitted as a method for ante-mortem diagnosis. CSF samples were taken from 14 animals suffering from BoHV-5 encephalitis, diagnosed by characteristic histopathological lesions in the brain and by identification of the virus genome by PCR in different portions of the brain. Virus DNA was detected in the CSF of 21.42% (3/14) of the evaluated animals. Ante-mortem detection of the virus genome in the CSF showed low sensitivity to confirm the diagnosis. The diagnosis is confirmed by a positive result but a negative one does not discard the disease.(AU)