Alessandra Figueiredo de Castro Nassar

Prevalence of Neospora caninum antibodies in sheep flocks of Uberlândia county, MG

Neosporosis is a parasitic disease that occurs in sheep and is associated with reproductive failure. The aim of this study was to verify seroprevalence of Neospora caninum antibodies in 12 sheep flocks in Uberlândia county, Minas Gerais, Brazil, using Indirect Immunofluorescence Assay (IFA). A total of 334 sheep blood samples were analyzed and an epidemiologic questionnaire was applied for each farm in order to correlate with risk factors of neosporosis: gender, age, breed, abortion problems, contact with cattle and dogs, and presence of wild canids. The prevalence of Neospora caninum antibodies in sheep was 8.1%, with titers ranging from 50 to 3200 and 83.3% of farms detected at least one ovine reactive. There was statistically significant difference in flocks with abortion problems associated with the presence of Neospora caninum antibodies (p < 0.05).

Pathogenicity of different rabies virus isolates and protection test in vaccinated mice

This study was aimed to evaluate and compare the pathogenicity of rabies virus isolated from bats and dogs, and to verify the efficacy of a commercial rabies vaccine against these isolates. For evaluation of pathogenicity, mice were inoculated by the intramuscular route (IM) with 500MICLD₅₀/0.03 mL of the viruses. The cross-protection test was performed by vaccinating groups of mice by the subcutaneous route and challenged through the intracerebral (IC) route. Isolates were fully pathogenic when inoculated by the IC route. When inoculated intramuscularly, the pathogenicity observed showed different death rates: 60.0% for the Desmodus rotundus isolate; 50.0% for dog and Nyctinomops laticaudatus isolates; 40.0% for Artibeus lituratus isolate; 9.5% Molossus molossus isolate; and 5.2% for the Eptesicus furinalis isolate. Mice receiving two doses of the vaccine and challenged by the IC route with the isolates were fully protected. Mice receiving only one dose of vaccine were partially protected against the dog isolate. The isolates from bats were pathogenic by the IC route in mice. However, when inoculated through the intramuscular route, the same isolates were found with different degrees of pathogenicity. The results of this work suggest that a commercial vaccine protects mice from infection with bat rabies virus isolates, in addition to a canine rabies virus isolate.

Clostridium perfringens types A and D associated with enterotoxemia in an 18-month-old goat

Postmortem examination of a Boer buck that died peracutely revealed bowel and liver diffusely congested and edematous. Kidney was apparently edematous. Clostridium perfringens type A was isolated from bowel and type D from kidney. Microscopic examination revealed large areas of necrosis in the renal cortex and medulla (pulpy kidney disease), hyperemia and centrilobular necrosis of the liver, necrosis of the small-intestine wall, pulmonary edema and congestion, intense hyperemia of the cerebellum, hyperemia and edema of the brain.

Antibodies against pseudorabies virus in feral swine in southeast Brazil

Soros de 358 javalis (Sus scrofa), criados em sistema de semiconfinamento em propriedades do estado de Sao Paulo, foram coletados entre 1998 e 2000 e testados para anticorpos contra o virus da doenca de Aujeszky (VDA), pela tecnica de soroneutralizacao (SN) e ensaio imunoenzimatico (ELISA). Foram detectados animais soropositivos em tres das sete propriedades analisadas. Do total de javalis testados, 30,7% apresentaram anticorpos neutralizantes contra o VDA, com variacao de 25,2% a 100% nas propriedades com animais sororreagentes. O ELISA detectou menor numero de sororeagentes (19,3%), sendo a sensibilidade e a especificidade 57,3% e 97,6%, respectivamente, e a correlacao observada de 85,2% (P<0,0001). Os resultados mostram que a infeccao pelo virus da doenca de Aujeszky ocorre em criacoes de javalis no estado de Sao Paulo, e compromete o sucesso de um futuro programa de erradicacao da doenca na regiao.

Isolation and identification of bovine tuberculosis in a Brazilian herd (São Paulo)

Mycobacterium was verified in animals from a Brazilian dairy herd, a total of 42 samples from 30 cows were submitted to culture and the isolated strains were analyzed by two polymerase chain reaction (PCR), the first specific for species belonging to the Mycobacterium complex (MTBC) and the other for differentiating M. tuberculosis from M. bovis. Twenty seven samples (64.3%) from 18 animals (60%) were positive for mycobacteria by culture, including samples from 15 retrofaryngeal lymphnodes (55.5%), 9 prescapular lymphnodes (33.3%), 2 lungs (7.4%), and 1 liver (3.7%). All isolated colonies were confirmed by PCR to contain MTBC organisms, and were identified as M. bovis by the same methodology.

Isolamento do vírus da raiva em Artibeus fimbriatus no Estado de São Paulo

This is the first report of the isolation and identification of the rabies virus in the frugivorous bat Artibeus fimbriatus in the city of Sao José do Rio Preto, Sao Paulo State, Brazil. The virus was isolated from an animal found in an urban area. The animal was found on the ground under a tree, still alive. Diagnosis was made by direct immunofluorescence and intracerebral inoculation of mice.

Seroprevalence and risk factors of antibodies against Leptospira spp. in ovines from Uberlândia municipality, Minas Gerais state, Brazil

The objectives of the present study were to verify the seroprevalence of anti-Leptospira spp. antibodies, identify the most frequent serovars and the risk factors associated with the infection in Uberlândia, Minas Gerais, Brazil . A total of 334 ovines blood samples were collected in 12 farms from Uberlândia municipality to be evaluated by means the Microscopic Agglutination Test (MAT) against 22 serovars of Leptospira spp. and an epidemiologic questionnaire was applied for each farm in order to correlate with risk factors of leptospirosis: sex, age and breed as well as contact with cattle, contact with dogs and presence of rodents. The prevalence of seropositive to MAT was found in seventy four ovines (22.2%; CI 95% 17.6-26.4%), with titers ranging from 100 to 3200. The most frequent serovars identified were: Hardjo, Autumnalis, Hardjo and Wolffi association and Grippotyphosa. Statistically significant differences were found in males, pure breeds and presence of rodents (p<0.05). The prevalence of anti-Leptospira spp. antibodies found in the present study demonstrated that this bacterium occurs in ovines of Uberlândia municipality, MG, Brazil . The need for the adoption of efficient management for the control of rodents and infection in ovines in order to avoid leptospirosis in the local flocks and future transmission to humans.

GENOTYPING OF Clostridium perfringens ASSOCIATED WITH SUDDEN DEATH IN CATTLE

Toxigenic types of Clostridium perfringens are significant causative agents of enteric disease in domestic animals, although type E is presumably rare, appearing as an uncommon cause of enterotoxemia of lambs, calves and rabbits. We report herein the typing of 23 C. perfringens strains, by the polymerase chain reaction (PCR) technique, isolated from small intestine samples of bovines that have died suddenly, after manifesting or not enteric or neurological disorders. Two strains (8.7%) were identified as type E, two (8.7%) as type D and the remainder as type A (82.6%). Commercial toxoids available in Brazil have no label claims for efficacy against type E-associated enteritis; however, the present study shows the occurrence of this infection. Furthermore, there are no recent reports on Clostridium perfringens typing in the country.

Identification of Clostridium chauvoei in clinical samples cultures from blackleg cases by means of PCR

Foi detectada presenca de Clostridium chauvoei pela reacao de PCR a partir de cultivo em cooked meat medium de amostras de figado, musculo e medula ossea metatarsiana de sete bezerros acometidos de carbunculo sintomatico. O isolamento de uma amostra de musculo sob condicoes anaerobias revelou Clostridium perfringens em cultura pura.C. chauvoei presence was detected by means of polymerase chain reaction (PCR) from supernatant of culture in cooked meat medium of liver, muscle and metatarsian bone marrow samples of seven calves with blackleg symptoms. The isolation under anaerobic conditions of one muscle sample revealed Clostridium perfringens in pure culture.

Detecção de fatores de virulência em estirpes de Campylobacter spp. isoladas de carcaças de suínos abatidos em frigoríficos

The purposes of this study were to isolate and identify Campylobacter spp. strains from the carcasses (n=65), feces (n=65) and mesenteric lymph nodes (n=65) of swine slaughtered in abattoirs in the State of Sao Paulo and to detect the presence of the cdt gene complex - responsible for the expression of the virulence factor cytolethal distensive toxin - in these Campylobacter spp. strains through Multiplex-PCR. From 195 samples analyzed, Campylobacter spp. was isolated in 31 (15.9%): 29 (93,6%) samples of rectal swab, 1 (3.2%) carcass swab and 1 (3.2%) lymph node sample. The 28 strains of isolated C. coli were positive for CDT toxin genes and the three strains of isolated C. jejuni were negative for these genes. It was also the first time that the cdt gene cluster was detected in strains isolated from swine in the state of Sao Paulo. These findings indicate swine as a potential spreading source of virulent strains of Campylobacter coli, either for slaughterhouse staff or consumers of carcasses and sub products.