Abstract in English:
ABSTRACT.- Julião F.S., Souza B.M.P.S., Freitas D.S.,Oliveira L.S., Larangeira D.F., Dias-Lima A.G.,Souza V.M.M., Barrouin-Melo S.M., Moreira Jr E.D., Paule B.J.A. & Franke C.R. 2007. [Investigation of risk areas as complemental methodology for the control of canine visceral leishmaniasis.] Investigação de áreas de risco como metodologia complementar ao controle da leishmaniose visceral canina. Pesquisa Veterinária Brasileira 27(8):319-324. Laboratório de Infectologia Veterinária, Escola de Medicina Veterinária, Universidade Federal da Bahia, Av. Adhemar de Barros 500, Ondina, Salvador, BA 40170-110, Brazil. E-mail: franke@ufba.br
Risk areas of canine visceral leishmaniasis in the city of Camaçari, Bahia, Brazil, were investigated. A total of 278 dogs from 141 homes pertaining to 20 investigated risk areas was serologically screened (ELISA). The general seroprevalence was 21.7% (56/258) after exclusion of 20 dogs used at the beginning of the survey to limit the study area. The respective results of the univariated and multivariated analysis of factors related to infection of dogs by Leishmania chagasi, to vector distribu-tion pattern in the area and to the methodology used to localize the canine focuses are discussed.
Abstract in Portuguese:
ABSTRACT.- Julião F.S., Souza B.M.P.S., Freitas D.S.,Oliveira L.S., Larangeira D.F., Dias-Lima A.G.,Souza V.M.M., Barrouin-Melo S.M., Moreira Jr E.D., Paule B.J.A. & Franke C.R. 2007. [Investigation of risk areas as complemental methodology for the control of canine visceral leishmaniasis.] Investigação de áreas de risco como metodologia complementar ao controle da leishmaniose visceral canina. Pesquisa Veterinária Brasileira 27(8):319-324. Laboratório de Infectologia Veterinária, Escola de Medicina Veterinária, Universidade Federal da Bahia, Av. Adhemar de Barros 500, Ondina, Salvador, BA 40170-110, Brazil. E-mail: franke@ufba.br
Risk areas of canine visceral leishmaniasis in the city of Camaçari, Bahia, Brazil, were investigated. A total of 278 dogs from 141 homes pertaining to 20 investigated risk areas was serologically screened (ELISA). The general seroprevalence was 21.7% (56/258) after exclusion of 20 dogs used at the beginning of the survey to limit the study area. The respective results of the univariated and multivariated analysis of factors related to infection of dogs by Leishmania chagasi, to vector distribu-tion pattern in the area and to the methodology used to localize the canine focuses are discussed.
Abstract in English:
Lima V.M.F., Biazzono L., Silva A.C., Correa A.P.F.L. & Luvizotto M.C.R. 2005. Serological diagnosis of visceral leishmaniasis by an enzyme immunoassay using protein A in naturally infected dogs. Pesquisa Veterinária Brasileira 25(4):215-218. Departamento de Clínica, Cirurgia e Reprodução Animal, Faculdade de Medicina Veterinária, Universidade Estadual Paulista, Rua Clóvis Pestana 793, Araçatuba, SP 16050-680, Brazil. E-mail: vmflima@fmva.unesp.br
A rapid indirect enzyme-linked immunosorbent assay (ELISA) was developed for measuring antibodies against Leishmania chagasi using total antigen from lysed promastigotes. Fifty symptomatic mixed breed dogs from a region of high incidence of visceral leishmaniasis in Brazil were examined. The results showed that in the positive animals, diagnosed by cytological examination, the ELISA using protein A assay system (mean optical density ± SD / 2.078 ± 0.631) detected more antibodies than the anti-IgG assay (mean optical density ± SD / 1.008 ± 0.437), while in the negative animals, the results by both systems were similar. These results suggest that the ELISA assay using protein A peroxidase conjugated could be useful to detect early infected animals in endemic areas, and thus help to control the spread of the infection.
Abstract in Portuguese:
Lima V.M.F., Biazzono L., Silva A.C., Correa A.P.F.L. & Luvizotto M.C.R. 2005. Serological diagnosis of visceral leishmaniasis by an enzyme immunoassay using protein A in naturally infected dogs. Pesquisa Veterinária Brasileira 25(4):215-218. Departamento de Clínica, Cirurgia e Reprodução Animal, Faculdade de Medicina Veterinária, Universidade Estadual Paulista, Rua Clóvis Pestana 793, Araçatuba, SP 16050-680, Brazil. E-mail: vmflima@fmva.unesp.br
A rapid indirect enzyme-linked immunosorbent assay (ELISA) was developed for measuring antibodies against Leishmania chagasi using total antigen from lysed promastigotes. Fifty symptomatic mixed breed dogs from a region of high incidence of visceral leishmaniasis in Brazil were examined. The results showed that in the positive animals, diagnosed by cytological examination, the ELISA using protein A assay system (mean optical density ± SD / 2.078 ± 0.631) detected more antibodies than the anti-IgG assay (mean optical density ± SD / 1.008 ± 0.437), while in the negative animals, the results by both systems were similar. These results suggest that the ELISA assay using protein A peroxidase conjugated could be useful to detect early infected animals in endemic areas, and thus help to control the spread of the infection.
Abstract in English:
Lima E.F., Riet-Correa F., Castro R.S., Gomes A.A.B. & Lima F.S. 2005. [Clinical signs, distribution of the lesions in the central nervous system and epidemiology of rabies in northeastern Brazil.] Sinais clínicos, distribuição das lesões no sistema nervoso e epidemiologia da raiva em herbívoros na região Nordeste do Brasil. Pesquisa Veterinária Brasileira 25(4):250-264. Centro de Saúde e Tecnologia Rural, Campus de Patos, Universidade Federal de Campina Grande, Patos, PB 58700-000, Brazil. E-mail: riet@cstr.ufcg.br
Twenty four outbreaks of rabies in cattle, 4 in horses, 2 in sheep, and 2 in goats are reported in northeastern Brazil. All outbreaks occurred in the state of Paraíba, except one in horses that occurred in the state of Rio Grande do Norte. All outbreaks, except one in sheep, were probably transmitted by vampire-bats, but the transmission by foxes (Dusicyon vetulus) is also possible. Clinical signs were characteristic for distribution of the lesions in the central nervous system (CNS). In cattle, signs were mainly of the paralytic form of rabies, caused by lesions on the spinal cord, brain stem and cerebellum; but some animals showed also depression, excitation and other signs due to cerebral lesions. In 3 out of 5 horses, the main clinical signs were due to lesions in the cerebrum, and 2 had the paralytic form. From 4 sheep and 2 goats affected, 4 showed clinical signs of the paralytic form; but in 1 goat and 1 sheep the main clinical signs were caused by cerebral lesions. All affected animals, except 1 goat, had a clinical manifestation period of 2-8 days. The only gross lesions were distention of the urinary bladder in 4 cattle and distention of the rectum in 2 others. Two horses had skin lesions due to traumatic injury. Histologic lesions were diffuse non-suppurative encephalomyelitis and meningitis. In the horses, and in one goat with a clinical manifestation period of 35 days, the lesions were more severe, with neuronal necrosis, neuronophagia, and presence of axonal spheroids. Negri bodies were found in 87% (20/23) of the cattle cases examined histologically. In small ruminants Negri bodies were found in 83% (5/6) of the cases. In sheep, goats and cattle, Negri bodies were more frequent in the cerebellum, but they were found also in brain stem, spinal cord and cerebrum. In horses, Negri bodies were found in small amounts only in the cortex of one animal, and in the cortex and hippocampus of another. Histologic lesions and Negri bodies in the trigeminal ganglia were less frequent than in the CNS. These results show that in rabies of herbivores, clinical signs and distribution of lesions in the CNS are variable, so that for the diagnosis and adequate clinical evaluation and the histologic study of different areas of the CNS are necessary. This also suggests that when the fluorescent antibody test and mouse inoculation test are negative, they should be repeated with samples from different areas of the brain and spinal cord. Frequency data of diseases from 4 diagnostic laboratories were used to estimate cattle deaths due to rabies in 3 Brazilian states. In Paraíba, with a population of 918,262 cattle, the annual death rate is estimated in 8,609 heads. In Mato Grosso do Sul, with a population of 23 millions cattle, deaths caused by rabies are estimated in 149,500 heads, and in Rio Grande do Sul, with a cattle population of 13 millions, cattle deaths due to rabies are estimated in 13,000 to 16,250 heads. If these data are used to estimate cattle losses in Brazil, with a cattle population of 195 millions, it can be estimated that 842,688 deaths are caused annually by rabies.
Abstract in Portuguese:
Lima E.F., Riet-Correa F., Castro R.S., Gomes A.A.B. & Lima F.S. 2005. [Clinical signs, distribution of the lesions in the central nervous system and epidemiology of rabies in northeastern Brazil.] Sinais clínicos, distribuição das lesões no sistema nervoso e epidemiologia da raiva em herbívoros na região Nordeste do Brasil. Pesquisa Veterinária Brasileira 25(4):250-264. Centro de Saúde e Tecnologia Rural, Campus de Patos, Universidade Federal de Campina Grande, Patos, PB 58700-000, Brazil. E-mail: riet@cstr.ufcg.br
Twenty four outbreaks of rabies in cattle, 4 in horses, 2 in sheep, and 2 in goats are reported in northeastern Brazil. All outbreaks occurred in the state of Paraíba, except one in horses that occurred in the state of Rio Grande do Norte. All outbreaks, except one in sheep, were probably transmitted by vampire-bats, but the transmission by foxes (Dusicyon vetulus) is also possible. Clinical signs were characteristic for distribution of the lesions in the central nervous system (CNS). In cattle, signs were mainly of the paralytic form of rabies, caused by lesions on the spinal cord, brain stem and cerebellum; but some animals showed also depression, excitation and other signs due to cerebral lesions. In 3 out of 5 horses, the main clinical signs were due to lesions in the cerebrum, and 2 had the paralytic form. From 4 sheep and 2 goats affected, 4 showed clinical signs of the paralytic form; but in 1 goat and 1 sheep the main clinical signs were caused by cerebral lesions. All affected animals, except 1 goat, had a clinical manifestation period of 2-8 days. The only gross lesions were distention of the urinary bladder in 4 cattle and distention of the rectum in 2 others. Two horses had skin lesions due to traumatic injury. Histologic lesions were diffuse non-suppurative encephalomyelitis and meningitis. In the horses, and in one goat with a clinical manifestation period of 35 days, the lesions were more severe, with neuronal necrosis, neuronophagia, and presence of axonal spheroids. Negri bodies were found in 87% (20/23) of the cattle cases examined histologically. In small ruminants Negri bodies were found in 83% (5/6) of the cases. In sheep, goats and cattle, Negri bodies were more frequent in the cerebellum, but they were found also in brain stem, spinal cord and cerebrum. In horses, Negri bodies were found in small amounts only in the cortex of one animal, and in the cortex and hippocampus of another. Histologic lesions and Negri bodies in the trigeminal ganglia were less frequent than in the CNS. These results show that in rabies of herbivores, clinical signs and distribution of lesions in the CNS are variable, so that for the diagnosis and adequate clinical evaluation and the histologic study of different areas of the CNS are necessary. This also suggests that when the fluorescent antibody test and mouse inoculation test are negative, they should be repeated with samples from different areas of the brain and spinal cord. Frequency data of diseases from 4 diagnostic laboratories were used to estimate cattle deaths due to rabies in 3 Brazilian states. In Paraíba, with a population of 918,262 cattle, the annual death rate is estimated in 8,609 heads. In Mato Grosso do Sul, with a population of 23 millions cattle, deaths caused by rabies are estimated in 149,500 heads, and in Rio Grande do Sul, with a cattle population of 13 millions, cattle deaths due to rabies are estimated in 13,000 to 16,250 heads. If these data are used to estimate cattle losses in Brazil, with a cattle population of 195 millions, it can be estimated that 842,688 deaths are caused annually by rabies.
Abstract in English:
Simionatto S., Lima-Rosa C.A.V., Rubin L.L. & Canal C.W. 2005. [A nested-PCR protocol for detection of the chicken anemia virus.] Um protocolo de “nested-PCR” para detecção do virus da anemia das galinhas. Pesquisa Veterinária Brasileira 25(2):106-110. Laboratório de Virologia, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: claudio.canal@ufrgs.br
This paper reports a nested polymerase chain reaction (nested-PCR) protocol for detection of chicken anemia virus (CAV), the causal agent of infectious chicken anemia. For DNA extraction from clinical samples, a method based on guanidine thiocyanate was found more sensitive and practical than other extraction protocols tested. The pair of primers used in the initial PCR targeted a 664 bp fragment on the VP1 gene. The primers for the internal PCR targeted a fragment of 520 bp. The specificity of the primers was evaluated on samples of CAV controlled flocks. Thirty different viruses and bacteria isolated from chickens did not give rise to any amplification product in the assay. The sensitivity of the nested-PCR was determined on serial dilutions of a CAV vaccine. The nested-PCR was more sensitive than a one step PCR and was able to detect at least 0.16 TCID50 of the vaccine strain. In addition, the protocol employed here detected viral DNA from tissues, sera and litter from flocks with or without clinical signs of disease. It is concluded that the nested-PCR protocol described here is more sensitive, faster and less cumbersome than virus isolation in cell culture as a diagnostic technique for detection of CAV.
Abstract in Portuguese:
Simionatto S., Lima-Rosa C.A.V., Rubin L.L. & Canal C.W. 2005. [A nested-PCR protocol for detection of the chicken anemia virus.] Um protocolo de “nested-PCR” para detecção do virus da anemia das galinhas. Pesquisa Veterinária Brasileira 25(2):106-110. Laboratório de Virologia, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: claudio.canal@ufrgs.br
This paper reports a nested polymerase chain reaction (nested-PCR) protocol for detection of chicken anemia virus (CAV), the causal agent of infectious chicken anemia. For DNA extraction from clinical samples, a method based on guanidine thiocyanate was found more sensitive and practical than other extraction protocols tested. The pair of primers used in the initial PCR targeted a 664 bp fragment on the VP1 gene. The primers for the internal PCR targeted a fragment of 520 bp. The specificity of the primers was evaluated on samples of CAV controlled flocks. Thirty different viruses and bacteria isolated from chickens did not give rise to any amplification product in the assay. The sensitivity of the nested-PCR was determined on serial dilutions of a CAV vaccine. The nested-PCR was more sensitive than a one step PCR and was able to detect at least 0.16 TCID50 of the vaccine strain. In addition, the protocol employed here detected viral DNA from tissues, sera and litter from flocks with or without clinical signs of disease. It is concluded that the nested-PCR protocol described here is more sensitive, faster and less cumbersome than virus isolation in cell culture as a diagnostic technique for detection of CAV.
Abstract in English:
Lima E.F., Riet-Correa F., Tabosa I.M., Dantas A.F.M., Medeiros J.M. & Sucupira Júnior G. 2005. [Polioencephalomalacia in goats and sheep in the semiarid region of northeastern Brazil.] Polioencefalomalacia em caprinos e ovinos na região semi-árida do Nordeste do Brasil. Pesquisa Veterinária Brasileira 25(1):9-14. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, PB, Brazil. E-mail: riet@cstr.ufcg.edu.br
Seven outbreaks of polioencephalomalacia in goats and 3 in sheep are reported from the semiarid region of northeastern Brazil. Animals of different ages were affected in various seasons of the year. In 5 outbreaks the animals were supplemented with concentrate ration and in 5 others they were only grazing on pastures. In one outbreak sheep were supplemented with an energy-protein-mineral mixture containing 1.3% of sulfur flower. Clinical signs were characterized by blindness, depression, head pressing, circling, grinding of the teeth, incoordination, spastic paralysis, ataxia, depression of the palpebral and pupillary reflexes, lateral strabismus, nystagmus, and dilated pupils. Nine affected animals were treated with thiamine and dexamethasone; 7 of them recovered but 2 died. The diagnosis of the disease was based on the recovered animals after treatment and/or on the histologic lesions. The clinical course varied from 2 to 15 days. On three animals post-mortem examination was made. One had herniation of the cerebellum through the Foramen magnum and softening of the cerebral cortex. The cut surface of the cerebral cortex showed cavitation and yellowish discoloration. Another animal had only cerebellar herniation. In a third animal no gross lesions were observed. Histological changes in the 3 animals were laminar necrosis of the cerebral cortex, and in 2 malacia of the thalamus and the rostral colliculi was also observed. In 9 outbreaks the cause of the disease was not determined, but one was probably due to sulfur toxicosis caused by the high sulfur content of the energy-protein-mineral mixture containing 1.3% of sulfur flower (96% sulfur) and 30% chicken litter (0.39% sulfur).
Abstract in Portuguese:
Lima E.F., Riet-Correa F., Tabosa I.M., Dantas A.F.M., Medeiros J.M. & Sucupira Júnior G. 2005. [Polioencephalomalacia in goats and sheep in the semiarid region of northeastern Brazil.] Polioencefalomalacia em caprinos e ovinos na região semi-árida do Nordeste do Brasil. Pesquisa Veterinária Brasileira 25(1):9-14. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, PB, Brazil. E-mail: riet@cstr.ufcg.edu.br
Seven outbreaks of polioencephalomalacia in goats and 3 in sheep are reported from the semiarid region of northeastern Brazil. Animals of different ages were affected in various seasons of the year. In 5 outbreaks the animals were supplemented with concentrate ration and in 5 others they were only grazing on pastures. In one outbreak sheep were supplemented with an energy-protein-mineral mixture containing 1.3% of sulfur flower. Clinical signs were characterized by blindness, depression, head pressing, circling, grinding of the teeth, incoordination, spastic paralysis, ataxia, depression of the palpebral and pupillary reflexes, lateral strabismus, nystagmus, and dilated pupils. Nine affected animals were treated with thiamine and dexamethasone; 7 of them recovered but 2 died. The diagnosis of the disease was based on the recovered animals after treatment and/or on the histologic lesions. The clinical course varied from 2 to 15 days. On three animals post-mortem examination was made. One had herniation of the cerebellum through the Foramen magnum and softening of the cerebral cortex. The cut surface of the cerebral cortex showed cavitation and yellowish discoloration. Another animal had only cerebellar herniation. In a third animal no gross lesions were observed. Histological changes in the 3 animals were laminar necrosis of the cerebral cortex, and in 2 malacia of the thalamus and the rostral colliculi was also observed. In 9 outbreaks the cause of the disease was not determined, but one was probably due to sulfur toxicosis caused by the high sulfur content of the energy-protein-mineral mixture containing 1.3% of sulfur flower (96% sulfur) and 30% chicken litter (0.39% sulfur).
Abstract in English:
Lima E.S.C., Pinto P.S.A., Santos J.L., Vanetti M.C.D., Bevilacqua P.D., Almeida L.P., Pinto M.S. & Dias F.S. 2004. [Isolation of Salmonella sp and Staphylococcus aureus at swine slaughtering as subsidy for HACCP, the Hazard Analysis and Critical Control Point system.] Isolamento de Salmonella sp e Staphylococcus aureus no processo do abate suíno como subsídio ao sistema de Análise de Perigos e Pontos Críticos de Controle - APPCC. Pesquisa Veterinária Brasileira 24(4):185-190. Depto Veterinária, Universidade Federal de Viçosa, 36571-000 Viçosa, Minas Gerais, Brazil. E-mail: pintopsa@ufv.br
This study was done to evaluate the superficial contamination of swine carcasses by Salmonella sp and Staphylococcus aureus, the identification of microbiological hazards in different segments of the processing line, and critical control points (CCPs), through the quantification of risks. A total of 120 surface swabbing carcasses were collected in a slaughterhouse: after the scalding/dehairing (point A), before evisceration (B), after evisceration and splitting (C), and after 24 hours of refrigeration (D). Salmonella sp and S. aureus were isolated from 14 (11.7%) carcasses. No statistical difference between the points studied was observed. The number of S. aureus isolated was between 1.2 and 1.5 log UFC/cm2. It was concluded that the risks observed were the same for both microorganisms.
Abstract in Portuguese:
Lima E.S.C., Pinto P.S.A., Santos J.L., Vanetti M.C.D., Bevilacqua P.D., Almeida L.P., Pinto M.S. & Dias F.S. 2004. [Isolation of Salmonella sp and Staphylococcus aureus at swine slaughtering as subsidy for HACCP, the Hazard Analysis and Critical Control Point system.] Isolamento de Salmonella sp e Staphylococcus aureus no processo do abate suíno como subsídio ao sistema de Análise de Perigos e Pontos Críticos de Controle - APPCC. Pesquisa Veterinária Brasileira 24(4):185-190. Depto Veterinária, Universidade Federal de Viçosa, 36571-000 Viçosa, Minas Gerais, Brazil. E-mail: pintopsa@ufv.br
This study was done to evaluate the superficial contamination of swine carcasses by Salmonella sp and Staphylococcus aureus, the identification of microbiological hazards in different segments of the processing line, and critical control points (CCPs), through the quantification of risks. A total of 120 surface swabbing carcasses were collected in a slaughterhouse: after the scalding/dehairing (point A), before evisceration (B), after evisceration and splitting (C), and after 24 hours of refrigeration (D). Salmonella sp and S. aureus were isolated from 14 (11.7%) carcasses. No statistical difference between the points studied was observed. The number of S. aureus isolated was between 1.2 and 1.5 log UFC/cm2. It was concluded that the risks observed were the same for both microorganisms.
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.
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:
Spilki F.R, Esteves P.A., Lima M., Franco A.C., Chiminazzo C., Flores E.F., Weiblen R., Driemeier D. & Roehe P.M. 2004. Comparative pathogenicity of bovine herpesviruses type 1 (BHV-1) subtypes 1 (BHV-1.1) and 2a (BHV-1.2a). Pesquisa Veterinária Brasileira 24(1):43-49. Centro de Pesquisas Desidério Finamor, Fepagro Saúde Animal, Cx. Postal 47, Eldorado do Sul, RS 92990-000, Brazil. E-mail: proehe@ufrgs.br
The study aimed to examine the capacity of two bovine herpesvirus type 1 (BHV-1) isolates of different subtypes (EVI 123/96, BHV-1.1; SV265/98, BHV-1.2a) to induce respiratory disease in calves. These two isolates are representative of the BHV-1 subtypes prevalent in Brazil. Viral subtypes were confirmed by monoclonal antibody analysis and by restriction enzyme digestion of viral genomes. The viruses were inoculated intranasally into seven 3 months old calves (four with BHV-1.1, three with BHV-1.2a). Three other calves of identical age and condition were kept as uninfected controls. In both groups of infected calves, the clinical signs observed were consistent with typical infectious bovine rhinothracheitis (IBR), including pyrexia, apathy, anorexia, nasal and ocular mucopurulent discharges, erosions on the nasal mucosa, conjunctivitis, lachrymation, redness of nasal mucosa, dyspnoea, coughing, tracheal stridor and enlargement of retropharingeal, submandibular and cervical lymphnodes. No significant differences were observed between the clinical scores attributed to both groups. Virus shedding in nasal and ocular secretions were also similar, apart from a significant difference in nasal virus shedding on day 1 to 3 post-inoculation, which was higher for BHV-1.1 than for BHV-1.2a. Following corticosteroid induced reactivation of the latent infection, recrudescence of clinical signs was also observed, with no significant differences on both groups. It was concluded that both subtypes BHV-1.1 and BHV-1.2a were able to induce clinically undistinguishable respiratory disease in calves, either subsequent to a primary infection or following reactivation.
Abstract in Portuguese:
Spilki F.R, Esteves P.A., Lima M., Franco A.C., Chiminazzo C., Flores E.F., Weiblen R., Driemeier D. & Roehe P.M. 2004. Comparative pathogenicity of bovine herpesviruses type 1 (BHV-1) subtypes 1 (BHV-1.1) and 2a (BHV-1.2a). Pesquisa Veterinária Brasileira 24(1):43-49. Centro de Pesquisas Desidério Finamor, Fepagro Saúde Animal, Cx. Postal 47, Eldorado do Sul, RS 92990-000, Brazil. E-mail: proehe@ufrgs.br
The study aimed to examine the capacity of two bovine herpesvirus type 1 (BHV-1) isolates of different subtypes (EVI 123/96, BHV-1.1; SV265/98, BHV-1.2a) to induce respiratory disease in calves. These two isolates are representative of the BHV-1 subtypes prevalent in Brazil. Viral subtypes were confirmed by monoclonal antibody analysis and by restriction enzyme digestion of viral genomes. The viruses were inoculated intranasally into seven 3 months old calves (four with BHV-1.1, three with BHV-1.2a). Three other calves of identical age and condition were kept as uninfected controls. In both groups of infected calves, the clinical signs observed were consistent with typical infectious bovine rhinothracheitis (IBR), including pyrexia, apathy, anorexia, nasal and ocular mucopurulent discharges, erosions on the nasal mucosa, conjunctivitis, lachrymation, redness of nasal mucosa, dyspnoea, coughing, tracheal stridor and enlargement of retropharingeal, submandibular and cervical lymphnodes. No significant differences were observed between the clinical scores attributed to both groups. Virus shedding in nasal and ocular secretions were also similar, apart from a significant difference in nasal virus shedding on day 1 to 3 post-inoculation, which was higher for BHV-1.1 than for BHV-1.2a. Following corticosteroid induced reactivation of the latent infection, recrudescence of clinical signs was also observed, with no significant differences on both groups. It was concluded that both subtypes BHV-1.1 and BHV-1.2a were able to induce clinically undistinguishable respiratory disease in calves, either subsequent to a primary infection or following reactivation.
Abstract in English:
ABSTRACT:
Guimarães A.M., Lima J.D. & Ribeiro M.EB. 2003. Ultrastructure of Babesia equitrophozoites isolated in Minas Gerais, Brazil. Pesquisa Veterinária Brasileira 23(3):101-104. [Ultra-estrutura de trofozoítos de Babesia equi isolados em Minas Gerais, Brasil.] Departamento de Medicina Veterinária, Universidade Federal de Lavras, Cx. Postal 37, Lavras, MG 37200-000, Brazil. E-mail: amg@ufla.br
A transmission electron microscope study was carried out on Babesia equi obtained from a splenectomized horse, from the municipality of Santa Luzia, Minas Gerais, Brazil. The isolate was inoculated into two splenectomized foals (1.05 x 1010 parasitized erythrocytes by B. equi). Trophozoites have a single membrane in direct contact with the cytoplasm of the red blood cells, a prominent nucleus, well-developed rough and smooth endoplasmic reticulum, numerous free ribosomes and small food vacuóles. B. equi trophozoites have a cytostome and a long tubular feeding structure in direct contact with the blood plasmá.
Abstract in Portuguese:
RESUMO:
Guimarães A.M., Lima J.D. & Ribeiro M.EB. 2003. Ultrastructure of Babesia equitrophozoites isolated in Minas Gerais, Brazil. Pesquisa Veterinária Brasileira 23(3):101-104. [Ultra-estrutura de trofozoítos de Babesia equi isolados em Minas Gerais, Brasil.] Departamento de Medicina Veterinária, Universidade Federal de Lavras, Cx. Postal 37, Lavras, MG 37200-000, Brazil. E-mail: amg@ufla.br
Neste estudo de microsco-pia eletrônica de transmissão utilizou-se um isolado de Babesia equi obtido a partir de um eqüino esplenectomizado, oriundo do município de Santa Luzia, Minas Gerais, Brasil. O isolado foi inoculado em dois potros esplenectomizados (1,05 x 1010 eritrócitos parasitados com B. equi). Os trofozoítos apresentaram uma membrana simples em· contato direto com o citoplasma das· hemácias, núcleo proeminente, retículo endoplasmático liso e rugoso bem desenvolvidos, numerosos ribosomos livres e pequenos vacúolos alimentares. Em trofozoítos de B. equi foi observado citostoma e uma longa estrutura tubular de alimentação em contato direto com o plasma sangüíneo.
Abstract in English:
ABSTRACT.- Corbellini L.G., Pescador C.A., Frantz F.J., Lima M., Ferreiro L. & Driemeier D. 2003. [Abortus by Aspergillus fumigatus and Aspergillus niger in cattle in southern Brazil.] Aborto por Aspergillusfumigatus eAspergillus niger em bovinos no sul do Brasil. Pesquisa Veterinária Brasileira 23(2):82-86. Departamento de Patologia Clínica Veterinária UFRGS, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail:davetpat@vortex.ufrgs.br
Mycotic infection has worldwide distribution and may cause placentitis and abortion in almost ali domestic animais. From September 2001 through November 2002 specimens from 147 aborted bovine fetuses along with 34 placentas were submitted to the Laboratory of Veterinary Pathology, Universidade Federal do Rio Grande do Sul, to investigate infectious causes of abortion in southern Brazil. Mycotic abortion was diagnosed in five cases (3.4%). Aspergilfus fumigatus was isolated from four cases and A. niger from one. Virological, bacteriological and direct immunofluorescent antibody tests for Leptospira sp were negative in those cases where Aspergillus sp was cultured. The gestational age of those fetuses ranged from 5 to 8 months. Macroscopic lesions were observed in four cases. One had several Nodular lesions disseminated throughout the liver, two had skin lesions characterized by white-grayish round plaques mostly on the head and neck, and thickened cotyledons in two placentas sent with those fetuses. The histological lesions were observed in the liver, lungs and placenta and consisted primary of necrotizing hepatitis, suppurative bronchopneumonia of varying degrees and necrotizing placentitis. With the use of Grocott's methenamine-silver staining, septate hyphae could be observed in three cases, surrounding necrotizing lesions in the tiver of one fetus and in two placentas. In two cases hyphae were observed in placenta) tissues and not in fetal tissues, indicating the importance of the placenta in diagnosing mycotic abortion in cattle.
Abstract in Portuguese:
RESUMO.- Corbellini L.G., Pescador C.A., Frantz F.J., Lima M., Ferreiro L. & Driemeier D. 2003. [Abortus by Aspergillus fumigatus and Aspergillus niger in cattle in southern Brazil.] Aborto por Aspergillusfumigatus eAspergillus niger em bovinos no sul do Brasil. Pesquisa Veterinária Brasileira 23(2):82-86. Departamento de Patologia Clínica Veterinária UFRGS, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail:davetpat@vortex.ufrgs.br
As infecções micóticas apresentam distribuição mundial e podem causar placentite e aborto em diversas espécies de animais. Entre setembro 2001 e novembro 2002, foram processados no Setor de Patologia Veterinária, Universidade Federal do Rio Grande do Sul, 147 fetos bovinos abortados com o objetivo de avaliar as principais causas de aborto infeccioso bovino no sul do Brasil. Destes, 34 estavam acompanhados da placenta. Aborto micótico foi diagnosticado em cinco casos (3,4%) mediante cultivo puro de quatro amostras de Aspergillus fumigatus e uma de A. niger associado a lesões histológicas características de fungo. Os exames virológico, bacteriológico e imunofluorescência direta para Leptospira sp foram negativos nestes casos. A idade dos fetos variava entre 5 e 8 meses de idade. Lesões macroscópicas foram observadas em quatro casos e eram caracterizadas por áreas circulares multifocais branco-acinzentadas na pele, principalmente na região da cabeça e dorso, em dois fetos, lesões nodulares no fígado em um caso e espessamento dos cotilédones em duas placentas enviadas juntamente com os fetos. Lesões histológicas foram observadas principalmente no fígado, pulmão e placenta, caracterizadas por hepatite necrótica multifocal, broncopneumonia supurativa e placentite necrótica. Através da coloração de Grocott hifas septadas foram observadas em duas placentas e nas bordas das lesões necróticas no fígado de um feto. Em dois casos hifas foram observadas somente na placenta e não no feto, salientando-se a importância deste tecido para o diagnóstico de aborto micótico bovino.