PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

Flores E.F., Weiblen R., Vogel F.S.F., Roehe P.M., Alfieri A.A. & Pituco E.M. 2005. [Bovine viral diarrhea virus (BVDV) infection in Brazil: history, current situation and perspectives.] A infecção pelo vírus da Diarréia Viral Bovina (BVDV) no Brasil - histórico, situação atual e perspectivas. Pesquisa Veterinária Brasileira 25(3):125-134. Departamento de Medicina Veterinária Preventiva, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: flores@ccr.ufsm.br Bovine viral diarrhea virus (BVDV) is one of the most important pathogens of cattle worldwide. BVDV infection and associated diseases have been reported in Brazil since the late 1960ties. Several serological, virological, clinical and pathological reports demonstrate the widespread distribution of BVDV infection among Brazilian cattle. In addition to variable levels of positive serology in beef and dairy cattle, BVDV antibodies have been occasionally detected in swine, wild boars, goats, cervids and water buffaloes. BVDV infection has been diagnosed in aborted fetuses, buffy coats of persistently infected (PI) animals, clinical specimens from animals suffering from different clinical syndromes, semen of bulls of artificial insemination (AI) centers, in healthy fetuses and in commercial fetal bovine serum and/or cultured cells. About 50 isolates have been genetically and/or antigenically characterized up to date, whilst roughly an equivalent number of isolates awaits characterization. Most of the characterized isolates belong to BVDV-1 genotype, non-cytopathic (NCP) biotype, yet some BVDV-2 (and some CP BVDV) have been identified as well. Brazilian BVDV isolates display a high antigenic variability and are markedly different from North American vaccine strains. A few inactivated, polyvalent vaccines are currently licensed in the country, yet vaccination is still incipient in many regions: only about 2.5 million doses were marketed in 2003. The low serological cross-reactivity between vaccine strains and field isolates has recently stimulated national industries to develop vaccines containing Brazilian BVDV-1 and BVDV-2 strains. The overall knowledge about BVDV infection in Brazil has grown considerably in the last years, due to an increasing number of laboratories performing diagnosis and research. Studies on the pathogenesis, serological and molecular epidemiology and production of reagents for diagnosis have contributed decisively for the recent growing knowledge on BVDV infections in the country.

• Bovine viral diarrhea virus BVDV epidemiology diagnostic.

Abstract in Portuguese:

Flores E.F., Weiblen R., Vogel F.S.F., Roehe P.M., Alfieri A.A. & Pituco E.M. 2005. [Bovine viral diarrhea virus (BVDV) infection in Brazil: history, current situation and perspectives.] A infecção pelo vírus da Diarréia Viral Bovina (BVDV) no Brasil - histórico, situação atual e perspectivas. Pesquisa Veterinária Brasileira 25(3):125-134. Departamento de Medicina Veterinária Preventiva, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: flores@ccr.ufsm.br Bovine viral diarrhea virus (BVDV) is one of the most important pathogens of cattle worldwide. BVDV infection and associated diseases have been reported in Brazil since the late 1960ties. Several serological, virological, clinical and pathological reports demonstrate the widespread distribution of BVDV infection among Brazilian cattle. In addition to variable levels of positive serology in beef and dairy cattle, BVDV antibodies have been occasionally detected in swine, wild boars, goats, cervids and water buffaloes. BVDV infection has been diagnosed in aborted fetuses, buffy coats of persistently infected (PI) animals, clinical specimens from animals suffering from different clinical syndromes, semen of bulls of artificial insemination (AI) centers, in healthy fetuses and in commercial fetal bovine serum and/or cultured cells. About 50 isolates have been genetically and/or antigenically characterized up to date, whilst roughly an equivalent number of isolates awaits characterization. Most of the characterized isolates belong to BVDV-1 genotype, non-cytopathic (NCP) biotype, yet some BVDV-2 (and some CP BVDV) have been identified as well. Brazilian BVDV isolates display a high antigenic variability and are markedly different from North American vaccine strains. A few inactivated, polyvalent vaccines are currently licensed in the country, yet vaccination is still incipient in many regions: only about 2.5 million doses were marketed in 2003. The low serological cross-reactivity between vaccine strains and field isolates has recently stimulated national industries to develop vaccines containing Brazilian BVDV-1 and BVDV-2 strains. The overall knowledge about BVDV infection in Brazil has grown considerably in the last years, due to an increasing number of laboratories performing diagnosis and research. Studies on the pathogenesis, serological and molecular epidemiology and production of reagents for diagnosis have contributed decisively for the recent growing knowledge on BVDV infections in the country.

Abstract in English:

Zafalon L.F., Nader Filho A., Oliveira J.V. & Resende F.D. 2005. [Electrical conductivity and chloride concentration of milk as auxiliary diagnostic methods in bovine subclinical mastitis.] Comportamento da condutividade elétrica e do conteúdo de cloretos do leite como métodos auxiliares de diagnóstico na mastite subclínica bovina. Pesquisa Veterinária Brasileira 25(3):159-163. Depto Medicina Veterinária Preventiva e Reprodução Animal, FACVJ, Unesp - Campus de Jaboticabal, Via de Acesso Prof. Paulo Donato Castellane s/no, Jaboticabal, SP 14884-900, Brazil. E-mail: zafalon@iz.sp.gov.br Electrical conductivity measured by a hand-held meter and chloride concentration of milk were studied as auxiliary methods for diagnosis of bovine subclinical mastitis in the identification of affected mammary quarters where Staphylococcus aureus and Corynebacterium sp were later isolated. Tests were made during 2 years in Holstein cows of a dairy farm producing type C milk, where milking was performed once a day. Sensitivities of electrical conductivity and chloride concentration tests from mammary quarters, where Corynebacterium sp was isolated (65.3% and 78.3%, respectively), were superior to the found in mammary quarters where S. aureus was identified (55.4% and 68.2%, respectively). The efficacies of the two diagnostic tests were similar. Statistical significance was demonstrated with regression analysis of both tests of healthy mammary quarters and subclinical mastitis quarters infected with Staphylococcus aureus.

• Bovine subclinical mastitis electric conductivity chloride level Staphylococcus aureus Corynebacterium sp.

Abstract in Portuguese:

Zafalon L.F., Nader Filho A., Oliveira J.V. & Resende F.D. 2005. [Electrical conductivity and chloride concentration of milk as auxiliary diagnostic methods in bovine subclinical mastitis.] Comportamento da condutividade elétrica e do conteúdo de cloretos do leite como métodos auxiliares de diagnóstico na mastite subclínica bovina. Pesquisa Veterinária Brasileira 25(3):159-163. Depto Medicina Veterinária Preventiva e Reprodução Animal, FACVJ, Unesp - Campus de Jaboticabal, Via de Acesso Prof. Paulo Donato Castellane s/no, Jaboticabal, SP 14884-900, Brazil. E-mail: zafalon@iz.sp.gov.br Electrical conductivity measured by a hand-held meter and chloride concentration of milk were studied as auxiliary methods for diagnosis of bovine subclinical mastitis in the identification of affected mammary quarters where Staphylococcus aureus and Corynebacterium sp were later isolated. Tests were made during 2 years in Holstein cows of a dairy farm producing type C milk, where milking was performed once a day. Sensitivities of electrical conductivity and chloride concentration tests from mammary quarters, where Corynebacterium sp was isolated (65.3% and 78.3%, respectively), were superior to the found in mammary quarters where S. aureus was identified (55.4% and 68.2%, respectively). The efficacies of the two diagnostic tests were similar. Statistical significance was demonstrated with regression analysis of both tests of healthy mammary quarters and subclinical mastitis quarters infected with Staphylococcus aureus.

Abstract in English:

Faccini J.L.H., Santos A.C.G. & Bechara G.H. 2004. [Bovine demodicosis in the state of Paraíba, northeastern Brazil.] Demodicose bovina no Estado da Paraíba. Pesquisa Veterinária Brasileira 24(3):149-152. Depto Parasitologia Animal, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: faccini@ufrrj.br Cases of bovine demodicosis caused by Demodex bovis were reported in a Sindhi herd from December 1989 to January 1992. Both localized and generalized forms were diagnosed. This is the first report of the generalized form in Brazil. In the first two years, demodicosis was diagnosed only in cattle < 2 years old, whereas animals of all ages were positive in the last two years. Prevalence varied from 20.4% (11/54) to 53.1% (26/49) and 13.2% (12/91) to 14.8% (9/61) for cattle < 2 years old and > 2 years old, respectively. Clinical signs varied from a few small nodules to a thickened skin with soft large nodules in the localized and generalized forms, respectively. Main microscopic features of the nodules in the generalized form consisted of acanthosis with hyperqueratosis, chronic sebaceous adenitis, subcutaneous muscular necrosis, focal cellular degeneration of the epidermis basal layer and presence of large number of mites inside the lumen of dilated hair follicles. In addition, a chronic perifoliculitis was observed, characterized by lymphoplasmocytic infiltrate which also contained macrophages and neutrophils. It is suggested that poor nutrition and stress due to prolonged drought probably contributed to the increase of susceptibility of the herd to mite infestation.

• Demodex bovis demodicosis cattle pathology Brazil.

Abstract in Portuguese:

Faccini J.L.H., Santos A.C.G. & Bechara G.H. 2004. [Bovine demodicosis in the state of Paraíba, northeastern Brazil.] Demodicose bovina no Estado da Paraíba. Pesquisa Veterinária Brasileira 24(3):149-152. Depto Parasitologia Animal, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: faccini@ufrrj.br Cases of bovine demodicosis caused by Demodex bovis were reported in a Sindhi herd from December 1989 to January 1992. Both localized and generalized forms were diagnosed. This is the first report of the generalized form in Brazil. In the first two years, demodicosis was diagnosed only in cattle < 2 years old, whereas animals of all ages were positive in the last two years. Prevalence varied from 20.4% (11/54) to 53.1% (26/49) and 13.2% (12/91) to 14.8% (9/61) for cattle < 2 years old and > 2 years old, respectively. Clinical signs varied from a few small nodules to a thickened skin with soft large nodules in the localized and generalized forms, respectively. Main microscopic features of the nodules in the generalized form consisted of acanthosis with hyperqueratosis, chronic sebaceous adenitis, subcutaneous muscular necrosis, focal cellular degeneration of the epidermis basal layer and presence of large number of mites inside the lumen of dilated hair follicles. In addition, a chronic perifoliculitis was observed, characterized by lymphoplasmocytic infiltrate which also contained macrophages and neutrophils. It is suggested that poor nutrition and stress due to prolonged drought probably contributed to the increase of susceptibility of the herd to mite infestation.

Abstract in English:

Pereira M.S.V., Siqueira Júnior J.P. & Campos Takaki G.M. 2004. [Elimination of resistance to drugs by fluoroquinolones in bovine strains of Staphylococcus aureus.] Eliminação de resistência a drogas por fluorquinolonas em Staphylococcus aureus de origem bovina. Pesquisa Veterinária Brasileira 24(1):11-14. Depto Biologia Molecular, Centro de Ciências Exatas e da Natureza, Universidade Federal da Paraiba, João Pessoa, PB 58059-900, Brazil. E-mail: svieira@dbm.ufpb.br Bovine strains of Staphylococcus aureus were submitted to treatment with four fluoro-quinolones in subinhibitory concentrations (1/2 x MICs) to evaluate their influence on the curing of plasmids. Ciprofloxacin showed to be the most efficient by eliminating resistance to streptomycin, tetracyclin, penicillin, and cadmium nitrate. Norfloxacin and pefloxacin eliminated penicillin- and tetracyclin-resistance respectively. Otherwise, plasmids elimination by ofloxacin was not evidenced. The results obtained in this study confirm the potential of fluoroquinolones to eliminate antibiotic-resistant plasmids, and showed to be a valuable contribution for the prevention of multi-resistant strains, and may even enhance their sensitivity to other chemotherapeutic agents.

• Staphylococcus aureus fluoroquinolones elimination of resistance to drugs.

Abstract in Portuguese:

Pereira M.S.V., Siqueira Júnior J.P. & Campos Takaki G.M. 2004. [Elimination of resistance to drugs by fluoroquinolones in bovine strains of Staphylococcus aureus.] Eliminação de resistência a drogas por fluorquinolonas em Staphylococcus aureus de origem bovina. Pesquisa Veterinária Brasileira 24(1):11-14. Depto Biologia Molecular, Centro de Ciências Exatas e da Natureza, Universidade Federal da Paraiba, João Pessoa, PB 58059-900, Brazil. E-mail: svieira@dbm.ufpb.br Bovine strains of Staphylococcus aureus were submitted to treatment with four fluoro-quinolones in subinhibitory concentrations (1/2 x MICs) to evaluate their influence on the curing of plasmids. Ciprofloxacin showed to be the most efficient by eliminating resistance to streptomycin, tetracyclin, penicillin, and cadmium nitrate. Norfloxacin and pefloxacin eliminated penicillin- and tetracyclin-resistance respectively. Otherwise, plasmids elimination by ofloxacin was not evidenced. The results obtained in this study confirm the potential of fluoroquinolones to eliminate antibiotic-resistant plasmids, and showed to be a valuable contribution for the prevention of multi-resistant strains, and may even enhance their sensitivity to other chemotherapeutic agents.

Abstract in English:

Lima M., Flores E.F., Weiblen R., Flores F.S.F. & Arenhart S. 2004. [Characterization of bovine viral diarrhea virus (BVDV) types 1 and 2 isolates for use in vaccines.] Caracterização de amostras atenuadas do vírus da Diarréia Viral Bovina (BVDV) tipos 1 e 2 para uso em vacinas. Pesquisa Veterinária Brasileira 24(1):35-42. Depto Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, Santa Maria, RS 97105-900, Brazil. E-mail: flores@ccr.ufsm.br This article reports the characterization of two cytopathic isolates of bovine viral diarrhea virus (BVDV-1: IBSP-2; BVDV-2:SV-253) submitted to multiple passages (n=30) in tissue culture associated with ultraviolet irradiation. The vaccine candidate strains were characterized in vitro (plaque size and morphology, growth kinetics and antigenic profile) and in vivo (attenuation and serological response in calves). In vitro characterization of biologically cloned viruses obtained at passages 0, 1, 10, 20 and 30 demonstrated that the attenuation process did not significantly affect the phenotypic and antigenic properties of the viruses. No major differences in plaque size and morphology and in the growth kinetics in tissue culture were observed among the viruses obtained at different passages. Likewise, the antigenic profile of these viruses did not change upon successive passages in tissue culture, as ascertained by the pattern of binding by 48 monoclonal antibodies (mAbs). Intramuscular inoculation of both viruses (IBSP-2: 107.3 TCID50; SV-253: 106.8 TCID50) at passage 30 (p30) in twelve 15 months old heifers did not produce clinical signs, demonstrating the attenuation of the viruses. Following inoculation, infectious virus was detected in leucocytes of most inoculated animals (10/12) between days 3 and 6 post-inoculation (pi) and in nasal secretions of three animals (days 4, 7 and 8pi). However, the vaccine viruses were not transmitted to three seronegative calves maintained as sentinels. All vaccinated calves seroconverted at day 14 post-vaccination. A moderate to high serum neutralizing response against five Brazilian BVDV-1 (titers from 80 to ³1,280) and four Brazilian BVDV-2 isolates (titers from 20 to 640) was observed at day 33 post-vaccination (pv). In general, the highest titers were observed against the Brazilian BVDV-1 isolates. At day 240 post-vaccination, the animals received a booster administration (IBSP-2: 107.3 TCID50 and SV-253: 106.8 TCID50). Revaccination resulted in a strong anamnestic response in most animals, with increasing antibody titers mainly to BVDV-2. These are promising results towards the future use of these strains in modified-live vaccines for the control of BVDV infection in Brazil.

• Bovine viral diarrhea virus (BVDV) modified-live vaccine attenuation.

Abstract in Portuguese:

Lima M., Flores E.F., Weiblen R., Flores F.S.F. & Arenhart S. 2004. [Characterization of bovine viral diarrhea virus (BVDV) types 1 and 2 isolates for use in vaccines.] Caracterização de amostras atenuadas do vírus da Diarréia Viral Bovina (BVDV) tipos 1 e 2 para uso em vacinas. Pesquisa Veterinária Brasileira 24(1):35-42. Depto Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, Santa Maria, RS 97105-900, Brazil. E-mail: flores@ccr.ufsm.br This article reports the characterization of two cytopathic isolates of bovine viral diarrhea virus (BVDV-1: IBSP-2; BVDV-2:SV-253) submitted to multiple passages (n=30) in tissue culture associated with ultraviolet irradiation. The vaccine candidate strains were characterized in vitro (plaque size and morphology, growth kinetics and antigenic profile) and in vivo (attenuation and serological response in calves). In vitro characterization of biologically cloned viruses obtained at passages 0, 1, 10, 20 and 30 demonstrated that the attenuation process did not significantly affect the phenotypic and antigenic properties of the viruses. No major differences in plaque size and morphology and in the growth kinetics in tissue culture were observed among the viruses obtained at different passages. Likewise, the antigenic profile of these viruses did not change upon successive passages in tissue culture, as ascertained by the pattern of binding by 48 monoclonal antibodies (mAbs). Intramuscular inoculation of both viruses (IBSP-2: 107.3 TCID50; SV-253: 106.8 TCID50) at passage 30 (p30) in twelve 15 months old heifers did not produce clinical signs, demonstrating the attenuation of the viruses. Following inoculation, infectious virus was detected in leucocytes of most inoculated animals (10/12) between days 3 and 6 post-inoculation (pi) and in nasal secretions of three animals (days 4, 7 and 8pi). However, the vaccine viruses were not transmitted to three seronegative calves maintained as sentinels. All vaccinated calves seroconverted at day 14 post-vaccination. A moderate to high serum neutralizing response against five Brazilian BVDV-1 (titers from 80 to ³1,280) and four Brazilian BVDV-2 isolates (titers from 20 to 640) was observed at day 33 post-vaccination (pv). In general, the highest titers were observed against the Brazilian BVDV-1 isolates. At day 240 post-vaccination, the animals received a booster administration (IBSP-2: 107.3 TCID50 and SV-253: 106.8 TCID50). Revaccination resulted in a strong anamnestic response in most animals, with increasing antibody titers mainly to BVDV-2. These are promising results towards the future use of these strains in modified-live vaccines for the control of BVDV infection in Brazil.

Abstract in English:

ABSTRACT.- Peixoto P.V., Malafaia P., Miranda L.V., Canella C.F.C., Canella Filho, C.F.C. & Villas Boas F.V. 2003. [Reproduction performance of beef cattle cows given three different types of mineral supplements.] Eficiência reprodutiva de matrizes bovinas de corte submetidas a três diferentes tipos de suplementação mineral. Pesquisa Veterinária Brasileira 23(3):125-130. Depto Nutrição Animal e Pastagem, Inst. Zootecnia, UFRRJ, Km 47, Seropédica, RJ 23851-970, Brazil. E-mail: pvpeixoto@uol.com.br The reproduction performance of about 1,200 beef cows, raised on pasture and given three different mineral supplements, was evaluated during 5 years in Cássia county, Minas Gerais, Brazil. The cows were divided into three groups: For one group (A) a comercial mineral mixture was used in 1997 and 1998; for the second group (B) common salt and dicalcium phosphate 1:1 was offered in 1999; and the third group (C) received only common salt during the sarne year. ln 2000 and 2001, ali the cows received exclusively common salt. There was no decrease in i:eproduction efficiency when only common salt was given; on the contrary, the reproduction performance of the inseminated e pregnant cows, thát was respectively 92.5 and 78.2 % (1997) and 92.2 and 80.5 % (1998), increased to 94.5 and 85.7 % (2000) and 96.7 and 89.7 % (2001). The decrease of reproduction performance of the cattle in 1999 was probably due to the severe drought during this year. The authors emphasize the importance of a selective mineral supplementation, i.e. to supplement cattle with mineral mixtures including only the elements which the animais can not obtain from the pasture. Theselective mineral supplementation requires the assistance of professionals with training and experience in clinics, pathology and nutrition of ruminants. These professionals should be able to accompany and evaluate the nutritional condition of a herd when a selective mineral mixture is used. Selective mineral supplementation could represent a two or threefold economy of the total cost of conventional supplementation with "complete" mineral mixtures. The authors discuss ifthe improvement of the reproduction performance of the cattle used in this fiel d experiment was due to a better management of the herd or to possible antagonism between the minerais.

• Cattle mineral deficiencies mineral supplementation tropical pastures Bovinos deficiências minerais pastagens tropicais suplementação mineral.

Abstract in Portuguese:

RESUMO.- Peixoto P.V., Malafaia P., Miranda L.V., Canella C.F.C., Canella Filho, C.F.C. & Villas Boas F.V. 2003. [Reproduction performance of beef cattle cows given three different types of mineral supplements.] Eficiência reprodutiva de matrizes bovinas de corte submetidas a três diferentes tipos de suplementação mineral. Pesquisa Veterinária Brasileira 23(3):125-130. Depto Nutrição Animal e Pastagem, Inst. Zootecnia, UFRRJ, Km 47, Seropédica, RJ 23851-970, Brazil. E-mail: pvpeixoto@uol.com.br Em uma fazenda do município de Cássia, Minas Gerais, o desempenho reprodutivo de aproximadamente 1200 matrizes bovinas de corte, criadas a campo, foi avaliado frente a três diferentes tipos de suplementação mineral, durante cinco anos. Enquanto que a mistura A (sal mineral comercial) foi oferecida nos anos de 1997 e 1998, a mistura B (cloreto de sódio 50% e fosfato bicálcico 50%) foi disponibilizada, em 1999, para as matrizes mantidas em um dos setores da fazenda e a mistura C (apenas cloreto de sódio), foi oferecida, neste mesmo ano, para os lotes cria dos em outros dois setores. Nos anos de 2000 e 2001, a mistura C foi ofertada a todas matrizes. Não houve queda na eficiência reprodutiva pela suplementação exclusiva com cloreto de sódio, pelo contrário, as percentagens de matrizes inseminadas e matrizes prenhes, que eram, respectivamente, de 92,5 e 78,2 (1997) e 92,2 e 80,5 (1998) alcançaram níveis de 94,5 e 85,7 (2000) e 96,7 e 89,7 (2001). A redução nos índices de matrizes inseminadas e de prenhez verificadas no ano de 1999 foi atribuída à baixa precipitação pluviométrica registrada naquele ano. Os autores ressalvam, porém, que a suplementação seletiva, isto é, aquela baseada na exclusiva administração do (s) mineral (is) que está (ão) faltando em uma determinada fazenda, só deve ser implantada mediante avaliação e acompanhamento clínico-nutricional do rebanho, o que exige apoio de profissional com adequados conhecimentos sobre nutrição, deficiências minerais e clínica de ruminantes. Por outro lado, a suplementação seletiva, pode representar uma despesa 2 a 3 vezes menor do que a verificada com a "mineralização" convencional do rebanho. Discute-se se a melhoria dos índices reprodutivos deveu-se à adequação do manejo ou à cessação de possível antagonismo entre os minerais.

Abstract in English:

ABSTRACT.- Peixoto P.V., França T.N., Barros C.S.L. & Tokarnia C.H. 2003. [Histopathological aspects of Bovine Enzootic Haematuria in Brazil.] Pesquisa Veterinaria Brasileira 23(2):65-81. Depto Nutrição Animal e Pastagem, Instituto de Zootecnia, UFRRJ, Km 47, Seropédica, Rio de Janeiro 23835-000, Brazil. E-mail: peixotop@ufrrj.br The bladder lesions of 59 cattle, from the States of Rio de Janeiro, São Paulo, Minas Gerais, Espírito Santo, Rio Grande do Sul, Santa Catarina, Paraná and Amazon, affected by Bovine Enzootic Haematuria (BEH), were studied histologically. The objective of this study was to describe and redassify neoplastic and non-neoplastic alterations not yet reported, according to the more complete current nomendature used in human medicine. There was an almost complete identity with alterations observed in the bladder of man. Due to the occurrence of two or more neoplasms in the sarne animal, differences in the methodology and in the concept of dassification, a more precise comparison was not possible. Coexistence of different types of epithelial and/or mesenchymal tumour growth was frequently seen. Rare neoplasms or differentiations not previously described were found in the bladder of some animais affected by BEH. These were trabecular carcinoma with Paneth cells differentiation, mesonephroid adenoma, mesonephroid adenocarcinoma, "signet ring" cell carcinoma, plasmocytoid carcinoma, chromophobe cell carcinoma and nested type of transitional cell carcinoma. Haemangiosarcomas originating from haemangiomas were also observed. This study also revealed the occurrence of many tumors with anaplasia and pronounced infiltrative features, but which did not metastasize. The elucidation of the cause of this "barrier against metastases" and its relationship with chemical carcinogenesis induced by the ptaquiloside, the active principie of bracken fern (Pteridium aquilinum), could be of interest to future research on the control of neoplasia in man and animais.

• Histopathology Bovine Enzootic Hematuria bladder tumors Pteridium aquilinum Brazil. Histopatologia Hematúria enzoótica bovina tumores de bexiga Brasil.

Abstract in Portuguese:

RESUMO.- Peixoto P.V., França T.N., Barros C.S.L. & Tokarnia C.H. 2003. [Histopathological aspects of Bovine Enzootic Haematuria in Brazil.] Pesquisa Veterinaria Brasileira 23(2):65-81. [Aspectos histopatológicos da Hematúria Enzoótica Bovina no Brasil.] Depto Nutrição Animal e Pastagem, Instituto de Zootecnia, UFRRJ, Km 47, Seropédica, Rio de Janeiro 23835-000, Brazil. E-mail: peixotop@ufrrj.br Com o objetivo de descrever alterações neoplásicas e não-neoplásicas ainda não relatadas e, paralelamente, reclassificá-las de acordo com nomenclatura mais completa e atual utilizada em medicina humana, foram estudadas, histologicamente, lesões da bexiga de 59 bovinos com Hematúria Enzoótica (HEB), oriundos dos Estados do Rio de Janeiro, São Paulo, Minas Gerais, Espírito Santo, Rio Grande do Sul, Santa Catarina, Paraná e Amazonas. Verificou-se, em termos qualitativos, quase uma perfeita identidade com as lesões de bexiga observadas em seres humanos. Comparações mais exatas com relação à freqüência dessas alterações ficaram prejudicadas, dadas a ocorrência de duas ou mais neoplasias em um mesmo animal e as diferenças da metodologia empregada ou do conceito de classificação. Coexistência entre neoplasias diversas, epiteliais e/ou mesenquimais, foi vista com freqüência. Neoplasias ou diferenciações raras, ainda não descritas na bexiga de bovinos, como carcinoma trabecular com diferenciação em células de Paneth, adenoma e adenocarcinoma mesonefróides, carcino ma "signet ring" (anel de sinete), carcinoma plasmocitóide, carcinoma de células cromófobas e carcinoma transicional tipo ninhado foram observadas na bexiga de alguns animais com HEB. Foram verificados hemangiossarcomas proliferando a partir de hemangiomas. O estudo revelou, ainda, a· ocorrência de. diversos tumores com anaplasia e carácter infiltrativo acentuados, incapazes, porém, de metastizarem. O esclarecimento da(s) causa(s) dessa "barreira à metástase" e suas relações com a carcinogênese química induzida pelo ptaquilosídeo, o princípio ativo de Pteridium aquilinum, talvez possa ser de interesse em futuros estudos que visem combater o câncer no homem e nos animais.

• Histopathology Bovine Enzootic Hematuria bladder tumors Pteridium aquilinum Brazil. Histopatologia Hematúria enzoótica bovina tumores de bexiga Brasil.

Abstract in English:

ABSTRACT.- França T.N., Tokarnia C.H. & Peixoto P.V. 2002. [Diseases caused by the radiomimetic principle of Pteridium aquilinum (Polypodiaceae). A review.] Enfermidades determinadas pelo princípio radiomimético de Pteridium aquilinum (Polypodiaceae). Pesquisa Veterinária Brasileira 22(3):85-96. Universidade Estácio de Sá, Curso de Medicina Veterinária, de Anatomia Patológica, Estrada Boca do Mato 850, Vargem Pequena, RJ 22783-320, Brazil. E-mail: ticiana@uol.com.br The more significant data concerning epidemiological, toxicological, clinical and pathological features observed in animals poisoned by Pteridium aquilinum (L.) Kuhn are presented. Bovine enzootic haematuria, upper digestive tract carcinomas, haemorrhagic syndrome, intestinal tumors and progressive retinal degeneration ("bright blindness") are reviewed stressing their importance. This review was made to bring to attention the economic importance of the plant regarding cattle raising and also the risk to human health.

• Pteridium aquilinum Polypodiaceae Bovine Enzootic Haematuria carcinomas of the upper digestive tract hemorrhagic diathesis bright blindness. Polypodiaceae hematúria enzoótica bovina carcinomas do aparelho digestivo superior diátese hemorrágica "bright blindness".

Abstract in Portuguese:

RESUMO.- França T.N., Tokarnia C.H. & Peixoto P.V. 2002. [Diseases caused by the radiomimetic principle of Pteridium aquilinum (Polypodiaceae). A review.] Enfermidades determinadas pelo princípio radiomimético de Pteridium aquilinum (Polypodiaceae). Pesquisa Veterinária Brasileira 22(3):85-96. Universidade Estácio de Sá, Curso de Medicina Veterinária, de Anatomia Patológica, Estrada Boca do Mato 850, Vargem Pequena, RJ 22783-320, Brazil. E-mail: ticiana@uol.com.br Por meio de revisão da literatura pertinente foram coligidos e são apresentados os principais dados relativos aos aspectos epidemiológicos, toxicológicos, clínicos, anátomo e histopatológicos observados nos casos de intoxicação pelo princípio radiomimético de Pteridium aquilinum (L.) Kuhn. São abordados a Hematúria Enzoótica Bovina (HEB), os Carcinomas das Vias Digestivas Superiores (CVDS), a Diátese Hemorrágica (DH), os Tumores Intestinais (TI) e a Degeneração Progressiva da Retina (DPR), com ênfase proporcional à importância de cada entidade. Esse estudo objetiva chamar a atenção para o especial significado dessa planta para a pecuária, em função dos prejuízos econômicos por ela determinados e, também, pelo provável risco que ela representa para a saúde humana.

Abstract in English:

ABSTRACT.- Scherer C.F.C., Flores E.F., Weiblen R., Kreutz L.C., Dürr J.W., Brum L.P., Quadros V.L. & Lima M. 2000. [A rapid virus-neutralization test for detection of antibodies against bovine viral diarrhea virus (BVDV) in milk.] Técnica rápida de neutralização viral para pesquisa de anticorpos contra o vírus da Diarréia Viral Bovina (BVDV) no leite. Pesquisa Veterinária Brasileira 22(2):45-50. Departamento de Medicina Veterinária Preventiva, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. The identification of bovine viral diarrhea virus (BVDV) positive herds through detection of antibodies in milk may viabilize large scale control/eradication programs. With this objective, the virus neutralization test (VN) was adapted to detect BVDV antibodies in milk. The adaptation consisted of a reduction in the time of incubation followed by detection of viral antigens in the indicator cells by immunofluorescence (IFA) and allowed readings at 24 hours. The rapid virus neutralization test (RVN) was initially tested in 1,335 serum samples, showing a 93. 7% sensitivity and 91.1 % agreement with the traditional VN. The RVN was also used to test 423 bovine sera that were toxic for cell culture in the traditional VN test, detecting 316 (74.7%) positive samples. Testing of matched serum and milk samples from BVDV seropositive cows showed that the VNR can detect antibodies in the milk of cows with serum neutralizing titers as low as 10. Anti-BVDV neutralizing activity was detected in milk of 97.4% (191/196) of cows with serum titers 3320; in 92.9% (79/85) of cows with titers of 160; in 88% (59/67) of cows with serum titers of 80. The frequency of BVDV antibodies in milk was 76.9% (40/52) for cows with serum titers of 40; 61.3% (19/31) for cows with titers of 20 and 33.3% (10/30) for cows with serum titers of 20. These results demonstrate that the RVN test is adequate for detecting BVDV antibodies in milk, mainly in cows having moderate to high serum titers, and therefore may be used for testing bulk milk samples to identify herds with viral activity. The use of this test may viabilize large scale programs for control/eradication of BVDV infection. It allows to assay a large number of samples and identify positive herds through testing milk routinely submitted for somatic cell counts (SCC), reducing costs with individual sample collection, shipping and testing.

• Bovine viral diarrhea virus BVDV diagnosis antibodies milk Vírus da Diarréia Viral Bovina diagnóstico leite anticorpos.

Abstract in Portuguese:

RESUMO.- Scherer C.F.C., Flores E.F., Weiblen R., Kreutz L.C., Dürr J.W., Brum L.P., Quadros V.L. & Lima M. 2000. [A rapid virus-neutralization test for detection of antibodies against bovine viral diarrhea virus (BVDV) in milk.] Técnica rápida de neutralização viral para pesquisa de anticorpos contra o vírus da Diarréia Viral Bovina (BVDV) no leite. Pesquisa Veterinária Brasileira 22(2):45-50. Departamento de Medicina Veterinária Preventiva, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. A identificação de rebanhos positivos para o vírus da Diarréia Viral Bovina (BVDV) através de detecção de anticorpos no leite pode viabilizar programas de controle em larga escala. Com esse objetivo, a técnica de soroneutralização (SN) foi adaptada para a pesquisa de anticorpos em amostras de leite. A adaptação consistiu na redução do tempo de incubação do teste, seguida da detecção de antígenos virais por imunofluorescência. A redução do tempo de incubação minimizou os efeitos tóxicos do leite sobre as células de cultivo, além de permitir a obtenção dos resultados em 24 horas. A técnica rápida (SNR) foi inicialmente testada em 1.335 amostras de soro bovino, apresentando sensibilidade de 93,7% e concordância de 91, 1% em relação à SN tradicional. A SNR foi também utilizada para testar 423 amostras de soro bovino que apresentaram toxicidade para as células na SN tradicional, detectando 316 (74,7%) amostras positivas. O teste de amostras de soro e leite de 520 vacas em lactação demonstrou que a SNR pode detectar anticorpos no leite de vacas com títulos séricos a partir de 10. Atividade neutralizante anti-BVDV no leite foi detectada em 97,4% (191/196) de vacas com títulos séricos 3 320; em 92,9% (79/85) de vacas com títulos de 160; em 88% (59/67) de vacas títulos de 80. A freqüência de animais positivos na SNR foi de 76,9% (40/52) para animais com títulos séricos de 40; 61,3% (19/31) com títulos de 20 e de 33,3% (10/30) para vacas com títulos de 10. Esses resultados demonstram que a técnica de SNR é adequada para a pesquisa de anticorpos anti-BVDV no leite, principalmente em animais com títulos moderados e altos de anticorpos. Essa técnica pode ser utilizada para testar amostras coletivas de leite e identificar rebanhos com atividade viral. A utilização dessa técnica pode viabilizar programas regionais de combate à infecção, pois permite testar um grande número de amostras e identificar rebanhos positivos através do leite enviado rotineiramente para contagem de células somáticas (CCS), reduzindo significativamente os custos com a coleta individual, transporte e teste de amostras.

Abstract in English:

ABSTRACT.- Spilki F.R., Esteves P.A., Franco A.C., Lima M., Holz C.L., Batista H.B.C.R., Driemeier D., Flores E.F., Weiblen R. & Roehe P.M. 2002. [Neurovirulence and neuroinvasiveness of bovine herpesvirus type 1 and 5 in rabbits.] Neurovirulência e neuroinvasividade de Herpesvírus bovinos tipos 1 e 5 em coelhos. Pesquisa Veterinária Brasileira 22(2):58-63. Centro de Pesquisas Veterinárias Desidério Finamor, Estrada do Conde 6000, Cx. Postal 47, Eldorado do Sul, RS 92990-000, Brazil. E-mail: proehe@orion.ufrgs.br In order to determine the capacity of bovine herpesvirus type 1 and 5 (BHV-1 and BHV-5) to invade, multiply and spread along the central nervous system (CNS) (neuroinvasiveness), as well as their potential to induce neurological illness (neurovirulence), 30 to 35 days old rabbits were inoculated with the BHV-5 strain EVI 88 / 95 and Los Angeles and Cooper BHV-1 strains, by the intrathecal (IT) and intranasal (IN) routes. The BHV-5 strain induced severe neurological clinical signs in 100% (12/12) of the rabbits inoculated by both routes. Histopathological examination revealed multifocal non-suppurative meningoencephalitis, characterized by multifocal gliosis and perivascular cuffing. Virus was recovered from many parts of the brain. Both BHV-1 strains, when inoculated via 1T route, were not neurovirulent. The strain Los Angeles, after IN inoculation, induced signs of severe respiratory disease (7/7), as well as signs of neurological impairment, indistinguishable from those induced by BHV-5, in 57% (4/7) of the infected rabbits. However, the rabbits with nervous signs revealed at histopathology vasculitis and thrombosis in lungs and brain, the latter with foci of neuronal necrosis, but no lesions indicative of encephalitis, suggesting that neural damage was probably consequent to tissue anoxia. The BHV-1 strain Cooper, after IN inoculation, induced only mild signs of respiratory disease. These findings indicate that the BHV-5 strain was both neuroinvasive and neurovirulent, since it was capable of invading, spreading and multiplying in the rabbits brains by both routes of inoculation, yet causing neurological disease, apparently consequent to vírus induced neural damage. The BHV-1 Los Angeles strain was not neuroinvasive, whereas its neurovirulence was probably consequent to tissue anoxia, which histologically seemed not to be related to direct viral pathogenic effect. The BHV-1 strain Cooper was neither neurovirulent nor neuroinvasive for rabbits. It is possible that these observations bear relationship with the frequent association of BHV-5 with encephalitis in cattle, as opposed to BHV-1 encephalitis, which is a rare event in nature.

• Infectious bovine rhinotracheitis IBR BHV-1 bovine encephalitis herpesvirus BHV-5 Rinotraqueíte infecciosa bovina herpesvírus da encefalite bovina.

Abstract in Portuguese:

RESUMO.- Spilki F.R., Esteves P.A., Franco A.C., Lima M., Holz C.L., Batista H.B.C.R., Driemeier D., Flores E.F., Weiblen R. & Roehe P.M. 2002. [Neurovirulence and neuroinvasiveness of bovine herpesvirus type 1 and 5 in rabbits.] Neurovirulência e neuroinvasividade de Herpesvírus bovinos tipos 1 e 5 em coelhos. Pesquisa Veterinária Brasileira 22(2):58-63. Centro de Pesquisas Veterinárias Desidério Finamor, Estrada do Conde 6000, Cx. Postal 47, Eldorado do Sul, RS 92990-000, Brazil. E-mail: proehe@orion.ufrgs.br Com o objetivo de avaliar a capacidade dos herpesvírus bovinos tipos 1 e 5 (BHV-1 e BHV-5) de invadir e replicar no sistema nervoso central (SNC) (neuroinvasividade), bem como sua capacidade de induzir doença neurológica (neurovirulência), coelhos com 30 a 35 dias de idade foram inoculados com uma amostra do Herpesvírus da Encefalite Bovina (BHV-5; amostra EVI 88/95) ou com amostras de BHV-1 (Los Angeles ou Cooper), pelas vias intratecal (IT) e intranasal (IN). A inoculação da amostra de BHV-5, tanto pela via 1T como IN, induziu sinais clínicos neurológicos em 100% (12/12) dos coelhos inoculados. Os exames histopatológicos revelaram um quadro de meningoencefalite não-purulenta multifocal, caracterizada por gliose multifocal e infiltrados perivasculares. O vírus foi isolado de várias áreas do SNC desses animais. As amostras de BHV-1, quando inoculadas pela via IT, não foram neurovirulentas. A amostra Los Angeles de BHV-1, quando administrada pela via IN, induziu sinais respiratórios severos, além de sinais neurológicos em 57% (4/7) dos animais inoculados. Entretanto, o exame histopatológico destes quatro animais revelou vasculite e trombose no pulmão e cérebro, este último apresentando focos de necrose neuronal, porém sem lesões indicativas de encefalite. Isso sugere que os sinais neurológicos foram, provavelmente, consequentes a prejuízos no fluxo sangüíneo encefálico, e não a danos neuronais provocados pela inoculação desse vírus. A amostra Cooper de BHV-1, quando inoculada pela via IN, induziu apenas sinais leves de infecção respiratória. Estes resultados indicam que apenas a amostra de BHV-5 foi capaz de invadir e replicar no encéfalo dos coelhos quando inoculada tanto por via IN como IT, apresentando neuroinvasividade e neurovirulência. É possível que estas observações tenham relação com o fato de amostras de BHV-5 freqüentemente causarem encefalites, em contraposição a infecções pelo BHV-1, onde encefalites são raramente observadas.