PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

Peixoto P.V., Malafaia P., Barbosa J.D. & Tokarnia C.H. 2005. [Principles of mineral supplementation in ruminants.] Princípios de suplementação mineral em ruminantes. Pesquisa Veterinária Brasileira 25(3):195-200. Depto Nutrição Animal e Pastagem, Instituto de Zootecnia, UFRRJ, Km 47, Seropédica, RJ 23890-000, Brazil. E-mail: pfpeixoto@terra.com.br Although there is solid knowledge on mineral deficiencies and their consequences on health and productivity of cattle in Brazil, paradoxically, those informations, most of the time, are not used by professionals of the agricultural sciences, who persist in stimulating the widespread use of the so-called complete mineral mixtures. The deficiency of many minerals included in these supplements, as iron, chrome, sulfur, and others, do not occur under natural conditions or only in rare and very particular situations. The present paper deals with the misunderstandings and problems related to traditional mineral supplementation and discusses the main aspects of the so-called selective mineral supplementation that is based in supplying exclusively the deficient mineral(s) and these only in necessary amounts. This procedure can result in expressive economy (sometimes up to 700%) when compared with the commercial mineral supplementation usually employed. According to several estimates, mineral supplementation can account for 20 to 30% of the total cost of beef cattle production on tropical pastures. A reversion assay, in which a group of cattle receives the commercial mineral mixture routinely used on the farm, and another group which receives the selective supplement, is the best option for the elucidation of positive or negative effects between the two possibilities of mineral supplementation on a specific farm. Trough this assay, the effects of the two compositions of mineral supplements can be investigated rationally over a sufficient period of time, with no risks and minimal possibilities of economic losses.

• Mineral deficiencies mineral supplementation ruminants cattle.

Abstract in Portuguese:

Peixoto P.V., Malafaia P., Barbosa J.D. & Tokarnia C.H. 2005. [Principles of mineral supplementation in ruminants.] Princípios de suplementação mineral em ruminantes. Pesquisa Veterinária Brasileira 25(3):195-200. Depto Nutrição Animal e Pastagem, Instituto de Zootecnia, UFRRJ, Km 47, Seropédica, RJ 23890-000, Brazil. E-mail: pfpeixoto@terra.com.br Although there is solid knowledge on mineral deficiencies and their consequences on health and productivity of cattle in Brazil, paradoxically, those informations, most of the time, are not used by professionals of the agricultural sciences, who persist in stimulating the widespread use of the so-called complete mineral mixtures. The deficiency of many minerals included in these supplements, as iron, chrome, sulfur, and others, do not occur under natural conditions or only in rare and very particular situations. The present paper deals with the misunderstandings and problems related to traditional mineral supplementation and discusses the main aspects of the so-called selective mineral supplementation that is based in supplying exclusively the deficient mineral(s) and these only in necessary amounts. This procedure can result in expressive economy (sometimes up to 700%) when compared with the commercial mineral supplementation usually employed. According to several estimates, mineral supplementation can account for 20 to 30% of the total cost of beef cattle production on tropical pastures. A reversion assay, in which a group of cattle receives the commercial mineral mixture routinely used on the farm, and another group which receives the selective supplement, is the best option for the elucidation of positive or negative effects between the two possibilities of mineral supplementation on a specific farm. Trough this assay, the effects of the two compositions of mineral supplements can be investigated rationally over a sufficient period of time, with no risks and minimal possibilities of economic losses.

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:

Catto J.B., Bianchin I., Torres Junior R.A.A. 2005. [Effects of deworming of cow-calf beef herds in brazilian savannas.] Efeitos da everminação de matrizes e de bezerros lactentes em sistema de produção de bovinos de corte na região de Cerrado. Pesquisa Veterinária Brasileira 25(3):188-194. Embrapa Gado de Corte, Rodov. 162, Km 4, Campo Grande, MS 79002-950, Brazil. E-mail: catto@cnpgc.embrapa.br The effect of deworming with ivermectin of cows before calving and of suckling calves on fecal egg counts (EPG) and productive performance of two beef cattle herds in Central Brazil was studied. Four groups of pregnant cows received the following treatments: T1- cows and calves not treated, T2- only calves treated, T3- only cows treated, and T4- cows and calves treated. The calves of T2 and T4 were distributed in the following treatments: A- calves treated at 3 to 5 months of age with long action ivermectin, B- treated with ivermectin, and C- control. For the cows, the deworming did not diminish the EPG during lactation and also did not have significant effect on the conception rate, live weight gain and the body weight of their calves at 3 to 5 months of age. The calves of treatment A gained, from the time of treatment to weaning (84 to 108 days), an average of 4.2kg (P=0.0003) and 7.1kg (P<0.0001) more than those of treatment B and C, respectively. The average difference in live weight gain of 2.9kg between the animals of treatment B and C was not significant. The EPG before treatment was not significantly different from the treatments (P=0.8665); but at weaning, the average EPG of the calves from treatment A was lower than for treatment B (P=0.0004) and C (P<0.0001). There was no significant difference in the mean EPG for the calves from treatment B and C.

• Beef cattle cows suckling calves nematodes treatment Brazilian savannas.

Abstract in Portuguese:

Catto J.B., Bianchin I., Torres Junior R.A.A. 2005. [Effects of deworming of cow-calf beef herds in brazilian savannas.] Efeitos da everminação de matrizes e de bezerros lactentes em sistema de produção de bovinos de corte na região de Cerrado. Pesquisa Veterinária Brasileira 25(3):188-194. Embrapa Gado de Corte, Rodov. 162, Km 4, Campo Grande, MS 79002-950, Brazil. E-mail: catto@cnpgc.embrapa.br The effect of deworming with ivermectin of cows before calving and of suckling calves on fecal egg counts (EPG) and productive performance of two beef cattle herds in Central Brazil was studied. Four groups of pregnant cows received the following treatments: T1- cows and calves not treated, T2- only calves treated, T3- only cows treated, and T4- cows and calves treated. The calves of T2 and T4 were distributed in the following treatments: A- calves treated at 3 to 5 months of age with long action ivermectin, B- treated with ivermectin, and C- control. For the cows, the deworming did not diminish the EPG during lactation and also did not have significant effect on the conception rate, live weight gain and the body weight of their calves at 3 to 5 months of age. The calves of treatment A gained, from the time of treatment to weaning (84 to 108 days), an average of 4.2kg (P=0.0003) and 7.1kg (P<0.0001) more than those of treatment B and C, respectively. The average difference in live weight gain of 2.9kg between the animals of treatment B and C was not significant. The EPG before treatment was not significantly different from the treatments (P=0.8665); but at weaning, the average EPG of the calves from treatment A was lower than for treatment B (P=0.0004) and C (P<0.0001). There was no significant difference in the mean EPG for the calves from treatment B and C.

Abstract in English:

Rech R.R., Schild A.L., Driemeier D., Garmatz S.L., Oliveira F.N., Riet-Correa F. & Barros C.S.L. 2005. [Malignant catarrhal fever in cattle in Rio Grande do Sul, Brazil: Epidemiology, clinical signs and pathology.] Febre catarral maligna em bovinos no Rio Grande do Sul: epidemiologia, sinais clínicos e patologia. Pesquisa Veterinária Brasileira 25(2):97-105. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br The epidemiology, clinical signs, necropsy and histopathological findings in cases of malignant catarrhal fever (MCF) occurring in cattle from 15 farms in Rio Grande do Sul, Brazil, from 1973 to 2003, are described. In 9 instances (60%) the disease occurred as sporadic cases affecting 1-3 cattle whereas in six farms (40%) MCF occurred as epizootics involving several cattle in each affected herd. Morbidity rates ranged from 2.4% to 20% and lethality rates were 83.3% and 100%. Cattle of all ages and both sexes were affected. Where the information was available (9 farms) sheep were in contact with affected cattle and cases of MCF occurred more frequently in spring and summer. Clinical courses were acute or subacute and clinical signs included fever, nasal and ocular discharges, conjunctivitis, drooling, hematuria, necrosis and blunting of buccal papillae, enlargement of lymph nodes, diarrhea and neurological disturbances. Necropsy findings included opaque corneas, reddening, erosions and ulcerations in several mucous membranes of the alimentary, respiratory and urogenital tracts, and the conjunctiva; enlargement and haemorrhage of lymph nodes and multiple white foci in the renal cortices and in the hepatic portal triads. Crustous dermatitis was observed in some cases. Main histopathological findings included vasculitis, necrosis of the surface epithelia and accumulation of inflammatory cells in several organs. Vasculitis were associated with fibrinoid necrosis of the medial layer of arteries and inflammatory cells included lymphoblasts, lymphocytes, plasma cells and macrophages.

• Infectious diseases epidemiology viral diseases diseases of cattle pathology.

Abstract in Portuguese:

Rech R.R., Schild A.L., Driemeier D., Garmatz S.L., Oliveira F.N., Riet-Correa F. & Barros C.S.L. 2005. [Malignant catarrhal fever in cattle in Rio Grande do Sul, Brazil: Epidemiology, clinical signs and pathology.] Febre catarral maligna em bovinos no Rio Grande do Sul: epidemiologia, sinais clínicos e patologia. Pesquisa Veterinária Brasileira 25(2):97-105. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br The epidemiology, clinical signs, necropsy and histopathological findings in cases of malignant catarrhal fever (MCF) occurring in cattle from 15 farms in Rio Grande do Sul, Brazil, from 1973 to 2003, are described. In 9 instances (60%) the disease occurred as sporadic cases affecting 1-3 cattle whereas in six farms (40%) MCF occurred as epizootics involving several cattle in each affected herd. Morbidity rates ranged from 2.4% to 20% and lethality rates were 83.3% and 100%. Cattle of all ages and both sexes were affected. Where the information was available (9 farms) sheep were in contact with affected cattle and cases of MCF occurred more frequently in spring and summer. Clinical courses were acute or subacute and clinical signs included fever, nasal and ocular discharges, conjunctivitis, drooling, hematuria, necrosis and blunting of buccal papillae, enlargement of lymph nodes, diarrhea and neurological disturbances. Necropsy findings included opaque corneas, reddening, erosions and ulcerations in several mucous membranes of the alimentary, respiratory and urogenital tracts, and the conjunctiva; enlargement and haemorrhage of lymph nodes and multiple white foci in the renal cortices and in the hepatic portal triads. Crustous dermatitis was observed in some cases. Main histopathological findings included vasculitis, necrosis of the surface epithelia and accumulation of inflammatory cells in several organs. Vasculitis were associated with fibrinoid necrosis of the medial layer of arteries and inflammatory cells included lymphoblasts, lymphocytes, plasma cells and macrophages.

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.

• Chicken anemia virus CAV molecular diagnosis nested-PCR.

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:

Rissi D.R., Rech R.R., Fighera R.A., Cagnini D.Q., Kommers G.D. & Barros C.S.L. 2005. [Spontaneous Baccharis coridifolia poisoning in cattle.] Intoxicação espontânea por Baccharis coridifolia em bovinos. Pesquisa Veterinária Brasileira 25(2):111-114. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Two outbreaks of Baccharis coridifolia poisoning in cattle in southern Brazil are described. Cases occurred when stressed, hungry and thirsty cattle brought from pastures free of B. coridifolia were placed into pastures heavily infested by this poisonous plant. In the two outbreaks morbidity was 21.73% and 22.51% and lethality was virtually 100%. Clinical signs included mild bloat, instability of hind limbs, muscle tremors, dry muzzle, dry feces or diarrhea, polydipsia and restlessness. Consistent necropsy findings included dehydration, large amounts of ruminal fluid, reddening and erosions of the mucosae of the forestomachs. Degeneration and necrosis of the lining epithelium of the forestomachs and of lymphoid tissue were the main histopathological changes encountered.

• Poisonous plants Baccharis coridifolia Asteraceae diseases of cattle pathology.

Abstract in Portuguese:

Rissi D.R., Rech R.R., Fighera R.A., Cagnini D.Q., Kommers G.D. & Barros C.S.L. 2005. [Spontaneous Baccharis coridifolia poisoning in cattle.] Intoxicação espontânea por Baccharis coridifolia em bovinos. Pesquisa Veterinária Brasileira 25(2):111-114. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Two outbreaks of Baccharis coridifolia poisoning in cattle in southern Brazil are described. Cases occurred when stressed, hungry and thirsty cattle brought from pastures free of B. coridifolia were placed into pastures heavily infested by this poisonous plant. In the two outbreaks morbidity was 21.73% and 22.51% and lethality was virtually 100%. Clinical signs included mild bloat, instability of hind limbs, muscle tremors, dry muzzle, dry feces or diarrhea, polydipsia and restlessness. Consistent necropsy findings included dehydration, large amounts of ruminal fluid, reddening and erosions of the mucosae of the forestomachs. Degeneration and necrosis of the lining epithelium of the forestomachs and of lymphoid tissue were the main histopathological changes encountered.

Abstract in English:

Simionatto S., Vaz E.K., Michelon A., Seixas F.K., Dellagostin O.A. 2005. [Development and evaluation of new strategies for immunization against swine colibacillosis.] Desenvolvimento e avaliação de novas estratégias de imunização contra colibacilose suína. Pes-quisa Veterinária Brasileira 25(2):84-90. Laboratório de Biologia Molecular, Centro de Bio-tecnologia, UFPel, Campus Capão do Leão, Cx. Postal 354, Pelotas, RS 96010-900, Brazil. E-mail: ssimionatto@bol.com.br Swine colibacillosis caused by enterotoxigenic Escherichia coli remains one of the main sanitary problems in pig farms. The recombinant DNA technology offers the possibility of developing new immunization strategies. This paper describes the development of a subunit vaccine through the expression and purification of the E. coli K88 FaeC fimbrial protein. The gene that codes for this antigen was amplified by PCR and cloned into an E. coli expression vector fused to a 6X histidine tag. The recombinant protein was purified by affinity chromatography and used for mice immunization. In parallel, the same gene was cloned into an eucariotic expression vector with the addition of the Kozak sequence for improving translation of this gene in muscle cells. The resulting plasmid named pUP310 was purified in large scale and used to immunize mice. The immune response afforded by both forms of immunization was monitored by ELISA. There was an immune response in mice inoculated with pUP310 and purified FaeC. It was possible to detect anti-FaeC antibodies 42 days after the first inoculation. The antibody titer increased with time, being still detectable 7 months after the first inoculation. It is concluded that recombinant FaeC and pUP310 are potential tools for immunization of swine against E. coli K88.

• Swine colibacillosis FaeC Escherichia coli DNA vaccine recombinant vaccine.

Abstract in Portuguese:

Simionatto S., Vaz E.K., Michelon A., Seixas F.K., Dellagostin O.A. 2005. [Development and evaluation of new strategies for immunization against swine colibacillosis.] Desenvolvimento e avaliação de novas estratégias de imunização contra colibacilose suína. Pes-quisa Veterinária Brasileira 25(2):84-90. Laboratório de Biologia Molecular, Centro de Bio-tecnologia, UFPel, Campus Capão do Leão, Cx. Postal 354, Pelotas, RS 96010-900, Brazil. E-mail: ssimionatto@bol.com.br Swine colibacillosis caused by enterotoxigenic Escherichia coli remains one of the main sanitary problems in pig farms. The recombinant DNA technology offers the possibility of developing new immunization strategies. This paper describes the development of a subunit vaccine through the expression and purification of the E. coli K88 FaeC fimbrial protein. The gene that codes for this antigen was amplified by PCR and cloned into an E. coli expression vector fused to a 6X histidine tag. The recombinant protein was purified by affinity chromatography and used for mice immunization. In parallel, the same gene was cloned into an eucariotic expression vector with the addition of the Kozak sequence for improving translation of this gene in muscle cells. The resulting plasmid named pUP310 was purified in large scale and used to immunize mice. The immune response afforded by both forms of immunization was monitored by ELISA. There was an immune response in mice inoculated with pUP310 and purified FaeC. It was possible to detect anti-FaeC antibodies 42 days after the first inoculation. The antibody titer increased with time, being still detectable 7 months after the first inoculation. It is concluded that recombinant FaeC and pUP310 are potential tools for immunization of swine against E. coli K88.

Abstract in English:

Hofer E. & Reis C.M.F. 2005. [Species and serovars of Listeria isolated from sick and clinically healthy animals in Brazil.] Espécies e sorovares de Listeria isolados de animais doentes e portadores no Brasil. Pesquisa Veterinária Brasileira 25(2):79-83. Laboratório de Zoonoses Bacterianas, Depto Bacteriologia, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, RJ 21045-900, Brazil. E-mail: ehofer@ioc.fiocruz.br Two hundred fourty-six strains of the genus Listeria were isolated from sick and clinically healthy animals, collected in three different regions of Brazil during 1971-2000. About 88.2% (217 cultures) yielded Listeria species from faecal specimens of healthy cattle and 29 strains (11.7%) were isolated from sick animals: 15 (6.0%) from central nervous system (CNS) and 14(5.6%) were from otherwise sterile sites. Phenotyping techniques were used to characterize the Listeria isolates. The commonest were L. innocua 6a and non-typable (140/56.9%), L. monocytogenes 4a (37/15.0%) and 4b (22/8.9%), originated mainly from stools of healthy cattle. From sick animals the predominant species and serovars were L. monocytogenes 4b (14/5.6%), and the higher incidence was observed in ruminants (12/4.8%) and 8/3.2% of the serovar 1a from other animal species (rodents and canines) mainly isolated from CNS samples.

• Listeria species serovars sick and healthy animals.

Abstract in Portuguese:

Hofer E. & Reis C.M.F. 2005. [Species and serovars of Listeria isolated from sick and clinically healthy animals in Brazil.] Espécies e sorovares de Listeria isolados de animais doentes e portadores no Brasil. Pesquisa Veterinária Brasileira 25(2):79-83. Laboratório de Zoonoses Bacterianas, Depto Bacteriologia, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, RJ 21045-900, Brazil. E-mail: ehofer@ioc.fiocruz.br Two hundred fourty-six strains of the genus Listeria were isolated from sick and clinically healthy animals, collected in three different regions of Brazil during 1971-2000. About 88.2% (217 cultures) yielded Listeria species from faecal specimens of healthy cattle and 29 strains (11.7%) were isolated from sick animals: 15 (6.0%) from central nervous system (CNS) and 14(5.6%) were from otherwise sterile sites. Phenotyping techniques were used to characterize the Listeria isolates. The commonest were L. innocua 6a and non-typable (140/56.9%), L. monocytogenes 4a (37/15.0%) and 4b (22/8.9%), originated mainly from stools of healthy cattle. From sick animals the predominant species and serovars were L. monocytogenes 4b (14/5.6%), and the higher incidence was observed in ruminants (12/4.8%) and 8/3.2% of the serovar 1a from other animal species (rodents and canines) mainly isolated from CNS samples.

Abstract in English:

Dutra I.S., Döbereiner J. & Souza A.M. 2005. [Botulism in beef and dairy cattle fed with poultry litter.] Botulismo em bovinos alimentados com cama de frango. Pesquisa Veterinária Brasileira 25(2):115-119. Depto Apoio, Produção e Saúde Animal, Curso de Medicina Veterinária, Universidade Estadual Paulista (Unesp), Rua Clóvis Pestana 793, Araçatuba, SP 16065-080, Brazil. E-mail: isdutra@fmva.unesp.br Outbreaks of botulism caused by type C and D of the botulinum toxin are frequent in Brazil, and are associated with bone chewing and ingestion of contaminated food and water. This paper reports the epidemiological, clinical, pathological and laboratorial aspects of 7 outbreaks of botulism in beef and dairy cattle fed with poultry litter, which occurred in the states of São Paulo and Minas Gerais, 1989-2000. Five outbreaks occurred in beef cattle herds, raised in confinement or under pasture conditions and supplemented with poultry litter, and 2 outbreaks occurred in dairy farms. From o total of 1,535 cattle supplemented regularily with poultry litter 455 animals (29.64%) died within 2 to 4 weeks. Morbidity and mortality varied from 3.47 to 100% in the 7 outbreaks. In one of the farms the lethality was 60.52%, and in others more than 88.43%, reaching 100% in three farms. Clinical signs were progressive paralysis, difficulties in moving, decubitus, normal alertness, decreased muscular tonus of tongue and tail, sialorrhoe and dyspnoe. At post-mortem examination of 30 cattle no noteable changes were observed. Spores of Clostridium botulinum were found in poultry litter samples collected on 7 farms. In liver, ruminal and intestinal fluid samples from 30 necropsied cattle botulinum toxin of type C (5) and D (9) or of the CD complex (1) were found in at least one of the samples collected from 15 animals, which confirms the clincial, pathological and epidemiological diagnosis of botulism.

• Botulism cattle poultry litter.

Abstract in Portuguese:

Dutra I.S., Döbereiner J. & Souza A.M. 2005. [Botulism in beef and dairy cattle fed with poultry litter.] Botulismo em bovinos alimentados com cama de frango. Pesquisa Veterinária Brasileira 25(2):115-119. Depto Apoio, Produção e Saúde Animal, Curso de Medicina Veterinária, Universidade Estadual Paulista (Unesp), Rua Clóvis Pestana 793, Araçatuba, SP 16065-080, Brazil. E-mail: isdutra@fmva.unesp.br Outbreaks of botulism caused by type C and D of the botulinum toxin are frequent in Brazil, and are associated with bone chewing and ingestion of contaminated food and water. This paper reports the epidemiological, clinical, pathological and laboratorial aspects of 7 outbreaks of botulism in beef and dairy cattle fed with poultry litter, which occurred in the states of São Paulo and Minas Gerais, 1989-2000. Five outbreaks occurred in beef cattle herds, raised in confinement or under pasture conditions and supplemented with poultry litter, and 2 outbreaks occurred in dairy farms. From o total of 1,535 cattle supplemented regularily with poultry litter 455 animals (29.64%) died within 2 to 4 weeks. Morbidity and mortality varied from 3.47 to 100% in the 7 outbreaks. In one of the farms the lethality was 60.52%, and in others more than 88.43%, reaching 100% in three farms. Clinical signs were progressive paralysis, difficulties in moving, decubitus, normal alertness, decreased muscular tonus of tongue and tail, sialorrhoe and dyspnoe. At post-mortem examination of 30 cattle no noteable changes were observed. Spores of Clostridium botulinum were found in poultry litter samples collected on 7 farms. In liver, ruminal and intestinal fluid samples from 30 necropsied cattle botulinum toxin of type C (5) and D (9) or of the CD complex (1) were found in at least one of the samples collected from 15 animals, which confirms the clincial, pathological and epidemiological diagnosis of botulism.