PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

Spilki F.R., Silva A.D., Batista H.B.C.R., Oliveira A.P., Winkelmann E., Franco A.C., Porciúncula J.A. & Roehe P.M. 2005. Field evaluation of safety during gestation and horizontal spread of a recombinant differential bovine herpesvirus 1 (BoHV-1) vaccine. Pesquisa Veterinária Brasileira 25(1):54-58. Instituto de Pesquisa Veterinária Desidério Finamor, Fepagro-Saúde Animal, Cx. Postal 47, Eldorado do Sul, RS 92990-000, Brazil. E-mail: proehe@ufrgs.br Bovine herpesvirus type 1 (BoHV-1) is recognized as a major cause of respiratory, reproductive disease and abortion in cattle. Vaccination is widely applied to minimize losses induced by BoHV-1 infections; however, vaccination of dams during pregnancy with modified live virus (MLV) vaccines has been occasionally associated to abortions. We have previously reported the development of a BoHV-1 recombinant virus, constructed with basis on a Brazilian BoHV-1 (Franco et al. 2002a) from which the gene coding for glycoprotein E (gE) was deleted (gE-) by genetic manipulation. Such recombinant has been previously evaluated in its potential as a differential vaccine (gE- vaccine) that allows differentiation between vaccinated and infected animals. Here, in the first part of the present study, the safety of the gE- vaccine during pregnancy was evaluated by the intramuscular inoculation of 107.4 tissue culture 50 % infective doses (TCID50) of the virus into 22 pregnant dams (14 BoHV-1 seronegative; 8 seropositive), at different stages of gestation. Other 15 pregnant dams were kept as non-vaccinated controls. No abortions, stillbirths or fetal abnormalities were seen after vaccination. Seroconversion was observed in both groups of previously seronegative vaccinated animals. In the second part of the study, the potential of the gE- vaccine virus to spread among beef cattle under field conditions was examined. Four heifers were inoculated intranasally with a larger amount (107,6 TCID50) of the gE- vaccine (to increase chances of transmission) and mixed with other sixteen animals at the same age and body condition, in the same grazing area, at a population density equal to the average cattle farming density within the region (one cattle head per 10,000 m2), for 180 days. All animals were monitored daily for clinical signs. Serum samples were collected on days 0, 30, 60 and 180 post-vaccination. Seroconversion was observed only in vaccinated heifers. These results indicate that, under the conditions of the present study, the gE- vaccine virus did not cause any noticeable harmful effect on pregnant dams and on its offspring and did not spread horizontally among cattle.

• Bovine herpesvirus 1 BoHV-1 recombinant gE- vaccine.

Abstract in Portuguese:

Spilki F.R., Silva A.D., Batista H.B.C.R., Oliveira A.P., Winkelmann E., Franco A.C., Porciúncula J.A. & Roehe P.M. 2005. Field evaluation of safety during gestation and horizontal spread of a recombinant differential bovine herpesvirus 1 (BoHV-1) vaccine. Pesquisa Veterinária Brasileira 25(1):54-58. Instituto de Pesquisa Veterinária Desidério Finamor, Fepagro-Saúde Animal, Cx. Postal 47, Eldorado do Sul, RS 92990-000, Brazil. E-mail: proehe@ufrgs.br Bovine herpesvirus type 1 (BoHV-1) is recognized as a major cause of respiratory, reproductive disease and abortion in cattle. Vaccination is widely applied to minimize losses induced by BoHV-1 infections; however, vaccination of dams during pregnancy with modified live virus (MLV) vaccines has been occasionally associated to abortions. We have previously reported the development of a BoHV-1 recombinant virus, constructed with basis on a Brazilian BoHV-1 (Franco et al. 2002a) from which the gene coding for glycoprotein E (gE) was deleted (gE-) by genetic manipulation. Such recombinant has been previously evaluated in its potential as a differential vaccine (gE- vaccine) that allows differentiation between vaccinated and infected animals. Here, in the first part of the present study, the safety of the gE- vaccine during pregnancy was evaluated by the intramuscular inoculation of 107.4 tissue culture 50 % infective doses (TCID50) of the virus into 22 pregnant dams (14 BoHV-1 seronegative; 8 seropositive), at different stages of gestation. Other 15 pregnant dams were kept as non-vaccinated controls. No abortions, stillbirths or fetal abnormalities were seen after vaccination. Seroconversion was observed in both groups of previously seronegative vaccinated animals. In the second part of the study, the potential of the gE- vaccine virus to spread among beef cattle under field conditions was examined. Four heifers were inoculated intranasally with a larger amount (107,6 TCID50) of the gE- vaccine (to increase chances of transmission) and mixed with other sixteen animals at the same age and body condition, in the same grazing area, at a population density equal to the average cattle farming density within the region (one cattle head per 10,000 m2), for 180 days. All animals were monitored daily for clinical signs. Serum samples were collected on days 0, 30, 60 and 180 post-vaccination. Seroconversion was observed only in vaccinated heifers. These results indicate that, under the conditions of the present study, the gE- vaccine virus did not cause any noticeable harmful effect on pregnant dams and on its offspring and did not spread horizontally among cattle.

Abstract in English:

Tokarnia C.H., Peixoto P.V., Döbereiner J., Barros S.S. & Riet-Correa F. 2004. [The outbreak of African swine fever which ocurred in 1978 in the county of Paracambi, Rio de Janeiro, Brazil.] O surto de peste suína africana ocorrido em 1978 no município de Paracambi, Rio de Janeiro. Pesquisa Veterinária Brasileira 24(4):223-238. Projeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ 23890-000, Brazil. E-mail: tokarnia@ufrrj.br Due to doubts which still persist 25 years after the outbreak of African swine fever (ASF) which ocurred in the county of Paracambi, Rio de Janeiro, Brazil, in 1978, the results obtained through the studies to establish and confirm the diagnosis are presented. These include data on the epidemiology, clinic-pathological aspects, bacteriological, virological and ultramicroscopic examinations, the experimental reproduction of the disease and cross immunity tests with classical swine fever virus performed in Brazil, and on the confirmation with isolation of the virus and determination of its identity at the Plum Island Animal Disease Center, New York, USA. The pigs of the affected herd had been fed untreated remains of meals from airplanes of international lines flying to Brazil from Portugal and Spain where ASF was occurring at the time. According to publication by the Ministry of Agriculture, after the diagnosis of the outbreak of ASF described in this paper, 223 additional outbreaks were reported in Brazil between 1978 and 1979, in all the Brazilian regions (North, Northeast, Central-West, Southeast and South). Further outbreaks were reported in 1981, but their number is not known. The last case was reported to have occurred on November 15, 1981, and on December 5, 1984, Brazil was declared free of ASF. For the diagnosis of ASF 54,002 samples were examined by the Department of Virology of the Institute of Microbiology, Federal University of Rio de Janeiro, from 1978 to 1981, by the techniques of haemadsorption in leucocyte cultures (HAd), direct immunoflorescence in tissue sections (FATS), direct immunoflorescence in cell cultures (FATCC), immuno-electro-osmophoresis (IEOP) and indirect immunoflorescence assay (IIF). Only 4 samples were positive with the FATCC procedure. This is the only technique which includes virus isolation; the origin of these positive samples was not reported, but probably they were from the Paracambi outbreak. From other suspected outbreaks of ASF in Brazil there is no information on the isolation and characterization of the virus isolates. Likewise there is no information available about the epidemiology, clinical signs, and pathology of suspected ASF in other outbreaks. The analysis of all published data on this matter in Brazil, the possibility of false-positive results, the lack of information about isolation and characterization of the virus, as well as the lack of epidemiological, clinical and pathological data of these other supposed outbreaks of ASF strongly suggest that the outbreak of Paracambi was the only occurrence of ASF in Brazil, confirmed by the isolation, identification of the virus, and the determination of its pathogenicity, and that ASF occurred and maintained itself confined to this area probably due to the early diagnosis and the rapid application of efficient control measures by the Brazilian authorities; the slaughter of the animals in the outbreak of Paracambi started as soon as 10 days after the first death, 3 days after the presumptive diagnosis.

• African swine fever Brazil pathology experimental reproduction.

Abstract in Portuguese:

Tokarnia C.H., Peixoto P.V., Döbereiner J., Barros S.S. & Riet-Correa F. 2004. [The outbreak of African swine fever which ocurred in 1978 in the county of Paracambi, Rio de Janeiro, Brazil.] O surto de peste suína africana ocorrido em 1978 no município de Paracambi, Rio de Janeiro. Pesquisa Veterinária Brasileira 24(4):223-238. Projeto Sanidade Animal Embrapa/UFRRJ, Km 47, Seropédica, RJ 23890-000, Brazil. E-mail: tokarnia@ufrrj.br Due to doubts which still persist 25 years after the outbreak of African swine fever (ASF) which ocurred in the county of Paracambi, Rio de Janeiro, Brazil, in 1978, the results obtained through the studies to establish and confirm the diagnosis are presented. These include data on the epidemiology, clinic-pathological aspects, bacteriological, virological and ultramicroscopic examinations, the experimental reproduction of the disease and cross immunity tests with classical swine fever virus performed in Brazil, and on the confirmation with isolation of the virus and determination of its identity at the Plum Island Animal Disease Center, New York, USA. The pigs of the affected herd had been fed untreated remains of meals from airplanes of international lines flying to Brazil from Portugal and Spain where ASF was occurring at the time. According to publication by the Ministry of Agriculture, after the diagnosis of the outbreak of ASF described in this paper, 223 additional outbreaks were reported in Brazil between 1978 and 1979, in all the Brazilian regions (North, Northeast, Central-West, Southeast and South). Further outbreaks were reported in 1981, but their number is not known. The last case was reported to have occurred on November 15, 1981, and on December 5, 1984, Brazil was declared free of ASF. For the diagnosis of ASF 54,002 samples were examined by the Department of Virology of the Institute of Microbiology, Federal University of Rio de Janeiro, from 1978 to 1981, by the techniques of haemadsorption in leucocyte cultures (HAd), direct immunoflorescence in tissue sections (FATS), direct immunoflorescence in cell cultures (FATCC), immuno-electro-osmophoresis (IEOP) and indirect immunoflorescence assay (IIF). Only 4 samples were positive with the FATCC procedure. This is the only technique which includes virus isolation; the origin of these positive samples was not reported, but probably they were from the Paracambi outbreak. From other suspected outbreaks of ASF in Brazil there is no information on the isolation and characterization of the virus isolates. Likewise there is no information available about the epidemiology, clinical signs, and pathology of suspected ASF in other outbreaks. The analysis of all published data on this matter in Brazil, the possibility of false-positive results, the lack of information about isolation and characterization of the virus, as well as the lack of epidemiological, clinical and pathological data of these other supposed outbreaks of ASF strongly suggest that the outbreak of Paracambi was the only occurrence of ASF in Brazil, confirmed by the isolation, identification of the virus, and the determination of its pathogenicity, and that ASF occurred and maintained itself confined to this area probably due to the early diagnosis and the rapid application of efficient control measures by the Brazilian authorities; the slaughter of the animals in the outbreak of Paracambi started as soon as 10 days after the first death, 3 days after the presumptive diagnosis.

Abstract in English:

Elias F., Schild A.L. & Riet-Correa F. 2004. [Bovine herpesvirus type-5 meningoencephalitis and malacia: histological lesions distribution in the central nervous system of naturally infected cattle.] Meningoencefalite e encefalomalacia por Herpesvírus bovino-5: distribuição das lesões no sistema nervoso central de bovinos naturalmente infectados. Pesquisa Veterinária Brasileira 24(3):123-131. Laboratório Regional de Diagnóstico, Faculdade de Veterinária, UFPel, Cx. Postal 354, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br The distribution of the histological lesions in the central nervous system (CNS) of cattle naturally infected by bovine herpes virus type-5 (BHV-5) was determined in 12 affected calves from 10 outbreaks of the disease diagnosed by the Regional Diagnostic Laboratory (LRD) at Pelotas University, from 1986 to 2003. The epidemiological data, clinical signs and duration of clinical course were obtained from the files of LRD. Transversal sections were performed at different levels in 10% formalin-fixed CNS. The sections were made in the frontal, parietal, temporal e occipital lobes of the telencephalic hemispheres, basal ganglia and internal capsule, thalamus, anterior colliculus, pons, cerebellar peduncles, cerebellum, medulla oblongata and cervical spinal cord. Paraffin embedded tissues were sectioned and stained with hematoxylin and eosin. The severity and distribution of the inflammatory and malacic lesions were evaluated in all sections. These lesions were related with the epidemiological and clinical aspects of the disease. The outbreaks of the disease were observed in different seasons of the year. Affected animals were 2 to 24-month-old, of different breeds and both sexes. Gross lesions characterized by yellow and depressed areas in the cerebral cortex were observed in five calves. In two of them, similar lesions were additionally observed in thalamus, basal nuclei, and internal capsule. Congestion and multifocal hemorrhages were observed in most cases. The histological lesions were characterized by non-suppurative meningoencephalitis in all sections of CNS, but more severe in the frontal cortex. Focal or widespread malacia with infiltration of Gitter cells were observed in all sections of cerebral cortex, basal ganglia, internal capsule, and thalamus. In some cases mild malacia was also observed in the rostral colliculi, pons, medulla, cerebellum and cervical spinal cord. Intranuclear inclusion bodies were seen in all cases studied; they were frequent in regions of the cerebral cortex near mild to moderate inflammatory or malacic lesions. In two cases the inclusion bodies were also seen in the basal ganglia and thalamus. The severity of the histological lesions was not proportional with the clinical course of the disease. The presence of lesions of malacia in different regions of the CNS, an aspect not mentioned in most reports of BHV-5 infections, could be due to variable pathogenicity of different virus isolates. Alternatively, it is possible that BHV-5 encephalitis occurs due to the reactivation of the virus in cattle previously affected by polioencefalomacia; this last sequence of events was already demonstrated experimentally by our research group.

• Bovine herpesvirus type-5 BHV-5 cattle meningoencephalitis polioencephalomalacia.

Abstract in Portuguese:

Elias F., Schild A.L. & Riet-Correa F. 2004. [Bovine herpesvirus type-5 meningoencephalitis and malacia: histological lesions distribution in the central nervous system of naturally infected cattle.] Meningoencefalite e encefalomalacia por Herpesvírus bovino-5: distribuição das lesões no sistema nervoso central de bovinos naturalmente infectados. Pesquisa Veterinária Brasileira 24(3):123-131. Laboratório Regional de Diagnóstico, Faculdade de Veterinária, UFPel, Cx. Postal 354, Pelotas, RS 96010-900, Brazil. E-mail: alschild@terra.com.br The distribution of the histological lesions in the central nervous system (CNS) of cattle naturally infected by bovine herpes virus type-5 (BHV-5) was determined in 12 affected calves from 10 outbreaks of the disease diagnosed by the Regional Diagnostic Laboratory (LRD) at Pelotas University, from 1986 to 2003. The epidemiological data, clinical signs and duration of clinical course were obtained from the files of LRD. Transversal sections were performed at different levels in 10% formalin-fixed CNS. The sections were made in the frontal, parietal, temporal e occipital lobes of the telencephalic hemispheres, basal ganglia and internal capsule, thalamus, anterior colliculus, pons, cerebellar peduncles, cerebellum, medulla oblongata and cervical spinal cord. Paraffin embedded tissues were sectioned and stained with hematoxylin and eosin. The severity and distribution of the inflammatory and malacic lesions were evaluated in all sections. These lesions were related with the epidemiological and clinical aspects of the disease. The outbreaks of the disease were observed in different seasons of the year. Affected animals were 2 to 24-month-old, of different breeds and both sexes. Gross lesions characterized by yellow and depressed areas in the cerebral cortex were observed in five calves. In two of them, similar lesions were additionally observed in thalamus, basal nuclei, and internal capsule. Congestion and multifocal hemorrhages were observed in most cases. The histological lesions were characterized by non-suppurative meningoencephalitis in all sections of CNS, but more severe in the frontal cortex. Focal or widespread malacia with infiltration of Gitter cells were observed in all sections of cerebral cortex, basal ganglia, internal capsule, and thalamus. In some cases mild malacia was also observed in the rostral colliculi, pons, medulla, cerebellum and cervical spinal cord. Intranuclear inclusion bodies were seen in all cases studied; they were frequent in regions of the cerebral cortex near mild to moderate inflammatory or malacic lesions. In two cases the inclusion bodies were also seen in the basal ganglia and thalamus. The severity of the histological lesions was not proportional with the clinical course of the disease. The presence of lesions of malacia in different regions of the CNS, an aspect not mentioned in most reports of BHV-5 infections, could be due to variable pathogenicity of different virus isolates. Alternatively, it is possible that BHV-5 encephalitis occurs due to the reactivation of the virus in cattle previously affected by polioencefalomacia; this last sequence of events was already demonstrated experimentally by our research group.

Abstract in English:

Paulovich F.B., Borowski S.M., Driemeier D., Razia L.E., Coutinho T. A., Prates A.B.H., Pescador C., Correa A. & Barcellos D.E.S.N. 2004. [Assessment of the pathogenicity of Brachyspira pilosicoli strains by conventional histopathological techniques and by immunohistochemistry.] Avaliação da patogenicidade de amostras de Brachyspira pilosicoli através de técnicas histopatológicas convencionais e por imuno-histoquímica. Pesquisa Veterinária Brasileira 24(3):144-148. Depto Patologia Clínica Veterinária, Faculdade de Veterinária, UFRGS, Cx. Postal 15094, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@vortex.ufrgs.br The study assessed differences of pathogenicity among 19 strains of Brachyspira pilosicoli isolated from cases of diarrhea in swine in the State of Rio Grande do Sul, Brazil, using an one-day-old chick model. The chicken inoculated with live bacterial cultures were submitted to euthanasia 21 days later, and the cecum was examined histologically using hematoxylin-eosin, silver staining and immunohistochemistry with a polyclonal antibody anti-Brachyspira pilosicoli. With silver staining and immunohistochemistry, respectively, 21.59% and 70.96% of the chicken showed colonization of the cecal epithelium with B. pilosicoli. Differences in the type of colonization characterized by continuous adhesion, focal adhesion or free bacteria in the intestinal lumen were observed. Immunohistochemistry was more efficient to assess intestinal colonization, because 49.37% more colonized chicken could be detected with silver staining. With three strains, elongated figures inside the cytoplasm of epithelial cecal cells in the inoculated chicken were observed.

• Brachyspira spp Brachyspira pilosicoli spirochetal colitis immunohistochemistry pathogenesis.

Abstract in Portuguese:

Paulovich F.B., Borowski S.M., Driemeier D., Razia L.E., Coutinho T. A., Prates A.B.H., Pescador C., Correa A. & Barcellos D.E.S.N. 2004. [Assessment of the pathogenicity of Brachyspira pilosicoli strains by conventional histopathological techniques and by immunohistochemistry.] Avaliação da patogenicidade de amostras de Brachyspira pilosicoli através de técnicas histopatológicas convencionais e por imuno-histoquímica. Pesquisa Veterinária Brasileira 24(3):144-148. Depto Patologia Clínica Veterinária, Faculdade de Veterinária, UFRGS, Cx. Postal 15094, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@vortex.ufrgs.br The study assessed differences of pathogenicity among 19 strains of Brachyspira pilosicoli isolated from cases of diarrhea in swine in the State of Rio Grande do Sul, Brazil, using an one-day-old chick model. The chicken inoculated with live bacterial cultures were submitted to euthanasia 21 days later, and the cecum was examined histologically using hematoxylin-eosin, silver staining and immunohistochemistry with a polyclonal antibody anti-Brachyspira pilosicoli. With silver staining and immunohistochemistry, respectively, 21.59% and 70.96% of the chicken showed colonization of the cecal epithelium with B. pilosicoli. Differences in the type of colonization characterized by continuous adhesion, focal adhesion or free bacteria in the intestinal lumen were observed. Immunohistochemistry was more efficient to assess intestinal colonization, because 49.37% more colonized chicken could be detected with silver staining. With three strains, elongated figures inside the cytoplasm of epithelial cecal cells in the inoculated chicken were observed.

Abstract in English:

Malafaia P., Peixoto P.V., Gonçalves J.C.S., Moreira A.L., Costa D.P.B. & Correa W.S. 2004. [Daily weight gain and costs of beef cattle receiving two types of mineral supple-ments.] Ganho de peso e custos em bovinos de corte submetidos a dois tipos de suplementos minerais. Pesquisa Veterinária Brasileira 24(3):160-164. Depto Nutrição Animal e Pastagem, Instituto de Zootecnia, UFRRJ, Seropédica, RJ 23851-970, Brazil. E-mail: malafaia1@ig.com.br The daily weight gain and economic aspects of beef cattle raised on tropical pastures receiving two types of mineral supplements were evaluated during 112-183 days during the wet season in 4 herds. On each farm the animals were divided into two groups. For one group a commercial mineral mixture was used, and to the other group a selective mineral mixture containing only Na, P, Cu and Co was offered. The cattle were weighed every 30 days, and the mineral supplement intake was measured monthly. The daily weight gain of the animals receiving the selective mineral mixture was greater in three farms. Only on the second farm the group receiving the commercial mineral mixture had a superior daily weight gain. The daily intake of the selective mineral mixture was lower in all groups and was attributed to the high amount of NaCl in these mixtures. The selective mineral supplementation was 3 up to 7 times more economic than the conventional supplementation with a “complete” mineral mix. Throughout the experimental period the animals did not show any direct or indirect clinical signs of mineral deficiency. The results of these experiments confirms the hypothesis that selective mineral supplementation – i.e. supplementation of the mineral element(s) deficient – was correct and results in expressive reduction of the cost with the mineral supplementation for beef cattle.

• Beef cattle mineral supplementation tropical forages.

Abstract in Portuguese:

Malafaia P., Peixoto P.V., Gonçalves J.C.S., Moreira A.L., Costa D.P.B. & Correa W.S. 2004. [Daily weight gain and costs of beef cattle receiving two types of mineral supple-ments.] Ganho de peso e custos em bovinos de corte submetidos a dois tipos de suplementos minerais. Pesquisa Veterinária Brasileira 24(3):160-164. Depto Nutrição Animal e Pastagem, Instituto de Zootecnia, UFRRJ, Seropédica, RJ 23851-970, Brazil. E-mail: malafaia1@ig.com.br The daily weight gain and economic aspects of beef cattle raised on tropical pastures receiving two types of mineral supplements were evaluated during 112-183 days during the wet season in 4 herds. On each farm the animals were divided into two groups. For one group a commercial mineral mixture was used, and to the other group a selective mineral mixture containing only Na, P, Cu and Co was offered. The cattle were weighed every 30 days, and the mineral supplement intake was measured monthly. The daily weight gain of the animals receiving the selective mineral mixture was greater in three farms. Only on the second farm the group receiving the commercial mineral mixture had a superior daily weight gain. The daily intake of the selective mineral mixture was lower in all groups and was attributed to the high amount of NaCl in these mixtures. The selective mineral supplementation was 3 up to 7 times more economic than the conventional supplementation with a “complete” mineral mix. Throughout the experimental period the animals did not show any direct or indirect clinical signs of mineral deficiency. The results of these experiments confirms the hypothesis that selective mineral supplementation – i.e. supplementation of the mineral element(s) deficient – was correct and results in expressive reduction of the cost with the mineral supplementation for beef cattle.

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.

• Infectious bovine rhinotracheitis IBR BHV-1.1 BHV-1.2a subtypes pathogenicity.

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.- 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.- 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.

• Bovine abortion mycotic abortion Aspergillus spp. Aborto bovino aborto micótico

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.

Abstract in English:

ABSTRACT.- Spilki F.R., Franco A.C., Teixeira M.B., Esteves P.A., Schaefer R., Schmidt E., Lemos R.A. & Roehe P.M. 2003. Bovine herpesvirus type 5 (BHV-5) in a calf with rabies. Pesquisa Veterinária Brasileira 23(1):1-4. Centro de Pesquisas Veterinárias Desidério Finamor, FepagroSaúde Animal, Cx. Postal 2076, Porto Alegre, RS 90001-970, Brazil. The brain of an one year old mal e calf which died with signs of neurological disease was submitted to the laboratory for rabies diagnosis. Microscopical findings included moderate mielitis, mild meningoencephalitis with perivascular cell cuffing and Negri inclusion bodies in Purkinje cells of the cerebellum. Rabies virus infection was further confirmed by the direct fluorescent antibody test as well as by mouse inoculation. ln addition, a herpesvirus was isolated from brain tissues. The isolate was antigenic and genetically characterized as bovine herpesvirus type 5 (BHV-5). It was not possible to determine whether BHV-5 played an active role in the outcome of the infection, since, the virus might have been present in a latent form in neural tissues. This is the first report of a mixed rabies/ BHV-5 infection in calves.

• Bovine herpesvirus type 5 BHV-5 rabies Herpesvírus bovino tipo 5 raiva.

Abstract in Portuguese:

RESUMO.- Spilki F.R., Franco A.C., Teixeira M.B., Esteves P.A., Schaefer R., Schmidt E., Lemos R.A. & Roehe P.M. 2003. Bovine herpesvirus type 5 (BHV-5) in a calf with rabies. Pesquisa Veterinária Brasileira 23(1):1-4. [Herpesvírus bovino tipo 5 (BHV-5) em bovino infectado pelo vírus da raiva.] Centro de Pesquisas Veterinárias Desidério Finamor, FepagroSaúde Animal, Cx. Postal 2076, Porto Alegre, RS 90001-970, Brazil. O encéfalo de um bezerro macho, de um ano de idade, que morreu com sinais de doença neurológica, foi submetido ao laboratório para diagnóstico de raiva. O exame histopatológico revelou mielite moderada, meningoencefalite leve com infiltração perivascular e corpúsculos de Negri nas células de Purkinje do cerebelo. A infecção pelo vírus rábico foi ainda confirmada por imunofluorescência diretá e por inoculação em camundongos. Além disso, um herpesvírus foi isolado dos tecidos do encéfalo. O vírus isolado foi antigênica e geneticamente caracterizado como Herpesvírus bovino tipo 5 (BHV-5). Não foi possível determinar se o BHV-5 teve algum papel ativo no desfecho da enfermidade, uma vez que o vírus poderia estar presente em forma latente nos tecidos neurais. Este é o primeiro relato de uma infecção mista pelo vírus da raiva e BHV-5 em bovinos.

Abstract in English:

ABSTRACT.- Franco A.C., Spilki F.R., Esteves P.A., Lima M., Weiblen R., Flores E.F., Rijsewijk F.A.M. & Roehe P.M. 2002. A Brazilian glycoprotein E-negative bovine herpesvirus type 1.2a (BHV-1.2a) mutant is attenuated for cattle and induces protection against wild-type virus challenge. Pesquisa Veterinária Brasileira 22(4):135-140. [Um mutante gE-negativo de herpesvírus bovino tipo 1.2a é atenuado para bovinos e induz proteção frente ao desafio com vírus de campo.] Centro de Pesquisas Veterinárias Desidério Finamor, Fepagro-Saúde Animal, Cx. Postal 2076, Porto Alegre, RS 90001-970, Brazil. E-mail: proehe@ufrgs.br The authors previously reported the construction of a glycoprotein E-deleted (gE·) mutante of bovine herpesvirus type 1.2a (BHV-1.2a). This mutant, 265gE·, was designed as a vacinal strain for differential vaccines, allowing the distinction between vaccinated and naturally infected cattle. In order to determine the safety and efficacy of this candidate vaccine virus, a group of calves was inoculated with 265gE·. The virus was detected in secretions of inoculated calves to lower titres and for a shorter period than the parental virus inoculated in control calves. Twenty one days after inoculation, the calves were challenged with the wild type parental virus. Only mild signs of infection were detected on vaccinated calves, whereas nonvaccinated controls displayed intense rhinotracheitis and shed virus for longer and to higher titres than vaccinated calves. Six months after vaccination, both vaccinated and control groups were subjected to reactivation of potentially latent virus. The mutant 265gE· could not be reactivated from vaccinated calves. The clinical signs observed, following the reactivation of the parental virus, were again much milder on vaccinated than on non-vaccinated calves. Moreover, parental vírus shedding was considerably reduced on vaccinated calves at reactivation. In view of its attenuation, immunogenicity and protective effect upon challenge and reactivation with a virulent BHV-1, the mutant 265gE· was shown to be suitable for use as a BHV-1 differential vaccine vírus.

• BHV-1 differential vaccine gE deletion IBR vacina diferencial gE.

Abstract in Portuguese:

RESUMO.- Franco A.C., Spilki F.R., Esteves P.A., Lima M., Weiblen R., Flores E.F., Rijsewijk F.A.M. & Roehe P.M. 2002. A Brazilian glycoprotein E-negative bovine herpesvirus type 1.2a (BHV-1.2a) mutant is attenuated for cattle and induces protection against wild-type virus challenge. Pesquisa Veterinária Brasileira 22(4):135-140. [Um mutante gE-negativo de herpesvírus bovino tipo 1.2a é atenuado para bovinos e induz proteção frente ao desafio com vírus de campo.] Centro de Pesquisas Veterinárias Desidério Finamor, Fepagro-Saúde Animal, Cx. Postal 2076, Porto Alegre, RS 90001-970, Brazil. E-mail: proehe@ufrgs.br Em estudo prévio os autores reportaram a construção de um mutante do Vírus da Rinotraqueíte Infecciosa Bovina (IBR) ou Herpesvírus Bovino tipo 1.2a (BHV-1.2a), do qual foi deletado o gene que codifica a glicoproteina E. Esse mutante (265gE-) foi construído a partir de uma amostra autóctone do vírus, tendo como objetivo seu uso como amostra vacinai em vacinas diferenciais, capazes de permitir a diferenciação entre animais vacinados e infectados com vírus de campo. Para determinar a atenuação e eficácia do 265gE· como imunógeno, bezerros foram inoculados por via intranasal com 106,9 DICC50 do mesmo. O vírus foi detectado em secreções dos animais inoculados em títulos mais baixos e por um período mais curto do que a amostra virulenta parental, inoculada em animais controle. Vinte e um dias após, os animais inoculados com o vírus mutante foram desafiados com a amostra parental, apresentando somente sinais leves de infecção. Os animais controle apresentaram intensa rinotraqueíte e excretaram vírus em títulos mais elevados e por mais tempo do que os vacinados. Seis meses após a vacinação, foi examinada a capacidade de reativação da infecção nos bezerros, através da administração de corticosteróides. O mutante 265gE- não foi reativado dos animais vàcinados. Os sinais clínicos consequentes à reativação do vírus parental foram muito atenuados nos animais vacinados, em comparação com os não vacinados. Além disso, a excreção de vírus de campo foi consideravelmente reduzida nestes últimos. Em vista de sua atenuação, imunogenicidade e efeito protetivo frente ao desafio com uma amostra virulenta de BHV-1 e subseqüente reativação, o mutante 265gE- demonstrou apresentar grande potencial para ser utilizado como vírus vacinai em vacinas diferenciais contra o BHV-1.