PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Mathias L.A., Meirelles R.B. & Buchala F.G. 2007. [Stability of Brucella abortus whole cell antigen for use in the serological diagnosis of bovine brucellosis by the complement fixation test.] Estabilidade do antígeno de célula total de Brucella abortus para uso no diagnóstico sorológico da brucelose bovina pela reação de fixação de complemento. Pesquisa Veterinária Brasileira 27(1):18-22. Departamento de Medicina Veterinária Preventiva e Reprodução Animal, Faculdade de Ciências Agrárias e Veterinárias (FCAV), Universidade Estadual Paulista (Unesp), Jaboticabal, SP 14884-900, Brazil. E-mail: lmathias@fcav.unesp.br The complement fixation test is used worldwide in the confirmatory diagnosis of bovine brucellosis. For this technique the antigen is the same as the one used in the tube agglutination test. However, literature is poor in information about the stability of the whole cell Brucella antigen for use in the complement fixation test to establish a time of validity of the antigen. Hence the aim of this investigation was to evaluate the stability of this antigen under refrigeration for use in the complement fixation test. Fourteen batches of antigen prepared with Brucella abortus strain 1119/3, produced from 9 months to 23 years and 11 months before, were analysed. One hundred and sixty-seven cattle sera with varying titres of antibodies to Brucella were tested through the warm complement fixation microtechnique with five 50% haemolytic units of complement. Sera with at least 25% of complement fixation in dilution 1:4 were considered positive. The results with 13 of the antigen batches were compared with the results obtained with the batch produced 9 months before by the McNemar c2 test and kappa statistic. The oldest antigen batch gave a higher proportion of sera titres which were exactly the same observed with the 9-month-batch (90.4%), and the antigen produced 4 years and 3 months before the test gave de lowest proportion of sera with the same titre of the 9-month-antigen (73.7%). The comparison of the results after being classified as positive and negative showed that the highest proportion of agreed results was observed with the antigen produced 21 years and 4 months before (98.8%, kappa 0.98). The antigen with the lowest proportion of agreed results was the one produced 3 years and 2 months before (91.6%, kappa 0.84). The results of the study show that most sera gave very similar results with all antigen batches evaluated, and that there was no relationship between the period of antigen production and the difference in test results.

• Bovine brucellosis serological diagnosis complement fixation test

Abstract in Portuguese:

ABSTRACT.- Mathias L.A., Meirelles R.B. & Buchala F.G. 2007. [Stability of Brucella abortus whole cell antigen for use in the serological diagnosis of bovine brucellosis by the complement fixation test.] Estabilidade do antígeno de célula total de Brucella abortus para uso no diagnóstico sorológico da brucelose bovina pela reação de fixação de complemento. Pesquisa Veterinária Brasileira 27(1):18-22. Departamento de Medicina Veterinária Preventiva e Reprodução Animal, Faculdade de Ciências Agrárias e Veterinárias (FCAV), Universidade Estadual Paulista (Unesp), Jaboticabal, SP 14884-900, Brazil. E-mail: lmathias@fcav.unesp.br The complement fixation test is used worldwide in the confirmatory diagnosis of bovine brucellosis. For this technique the antigen is the same as the one used in the tube agglutination test. However, literature is poor in information about the stability of the whole cell Brucella antigen for use in the complement fixation test to establish a time of validity of the antigen. Hence the aim of this investigation was to evaluate the stability of this antigen under refrigeration for use in the complement fixation test. Fourteen batches of antigen prepared with Brucella abortus strain 1119/3, produced from 9 months to 23 years and 11 months before, were analysed. One hundred and sixty-seven cattle sera with varying titres of antibodies to Brucella were tested through the warm complement fixation microtechnique with five 50% haemolytic units of complement. Sera with at least 25% of complement fixation in dilution 1:4 were considered positive. The results with 13 of the antigen batches were compared with the results obtained with the batch produced 9 months before by the McNemar c2 test and kappa statistic. The oldest antigen batch gave a higher proportion of sera titres which were exactly the same observed with the 9-month-batch (90.4%), and the antigen produced 4 years and 3 months before the test gave de lowest proportion of sera with the same titre of the 9-month-antigen (73.7%). The comparison of the results after being classified as positive and negative showed that the highest proportion of agreed results was observed with the antigen produced 21 years and 4 months before (98.8%, kappa 0.98). The antigen with the lowest proportion of agreed results was the one produced 3 years and 2 months before (91.6%, kappa 0.84). The results of the study show that most sera gave very similar results with all antigen batches evaluated, and that there was no relationship between the period of antigen production and the difference in test results.

Abstract in English:

ABSTRACT.- Brum K.B., Haraguchi M., Lemos R.A.A, Riet-Correa F. & Fioravanti M.C.S. 2007. Crystal-associated cholangiopathy in sheep grazing Brachiaria decumbens containing the saponin protodioscin. Pesquisa Veterinária Brasileira 27(1):39-42. Departamento de Patologia, Universidade Federal de Mato Grosso do Sul, Caixa Postal 549, Campo Grande, MS 79070-900, Brazil. E-mail: kbbrum@gmail.com An outbreak of hepatogenous photosensitization is reported in a flock of 28 sheep grazing Brachiaria decumbens in Mato Grosso do Sul State, Central-Western Brazil. Seven lambs and an adult sheep were affected and 6 of them died. Two surviving affected lambs and one lamb without clinical signs had increased serum values of gamma glutamyltransferase, bilirubin, and cholesterol. In two adult unaffected sheep those parameters were within normal values. An adult sheep submitted to necropsy presented moderate body condition, unilateral corneal opacity, drying of the muzzle, moderate jaundice, increased lobular pattern of the liver, and a distended gallbladder. Histological lesions were epithelial degeneration, necrosis, and hyperplasia of small bile ducts. Mild amounts of foamy macrophages were observed, mainly in the centroacinar zone. Diffuse swelling and vacuolation were observed in hepatocytes. Crystal negative images were found within bile ducts, foamy macrophages, and the lumen of some renal tubules. The heart showed multifocal areas of degeneration and necrosis of the muscle fibers. Pasture samples (Brachiaria decumbens) contained 2.36% of protodioscin. No Pithomyces chartarum spores were found in the pasture. Samples from a similar neighboring B. decumbens pasture grazed by cattle without photosensitization contained 1.63% of protodioscin isomers. Outbreaks of photosensitization caused by Brachiaria spp. are common in cattle in the Brazilian Cerrado (savanna) with about 51 million hectares of Brachiaria spp pastures. Sheep farming has been recently developed in this region, and the number of sheep is increasing significantly. Because sheep are more susceptible than cattle to lithogenic saponins, poisoning by Brachiaria should be an important limiting factor for the sheep industry.

• Sheep photosensitization Brachiaria decumbens protodioscin steroidal saponin cholangiopathy

Abstract in Portuguese:

ABSTRACT.- Brum K.B., Haraguchi M., Lemos R.A.A, Riet-Correa F. & Fioravanti M.C.S. 2007. Crystal-associated cholangiopathy in sheep grazing Brachiaria decumbens containing the saponin protodioscin. Pesquisa Veterinária Brasileira 27(1):39-42. Departamento de Patologia, Universidade Federal de Mato Grosso do Sul, Caixa Postal 549, Campo Grande, MS 79070-900, Brazil. E-mail: kbbrum@gmail.com An outbreak of hepatogenous photosensitization is reported in a flock of 28 sheep grazing Brachiaria decumbens in Mato Grosso do Sul State, Central-Western Brazil. Seven lambs and an adult sheep were affected and 6 of them died. Two surviving affected lambs and one lamb without clinical signs had increased serum values of gamma glutamyltransferase, bilirubin, and cholesterol. In two adult unaffected sheep those parameters were within normal values. An adult sheep submitted to necropsy presented moderate body condition, unilateral corneal opacity, drying of the muzzle, moderate jaundice, increased lobular pattern of the liver, and a distended gallbladder. Histological lesions were epithelial degeneration, necrosis, and hyperplasia of small bile ducts. Mild amounts of foamy macrophages were observed, mainly in the centroacinar zone. Diffuse swelling and vacuolation were observed in hepatocytes. Crystal negative images were found within bile ducts, foamy macrophages, and the lumen of some renal tubules. The heart showed multifocal areas of degeneration and necrosis of the muscle fibers. Pasture samples (Brachiaria decumbens) contained 2.36% of protodioscin. No Pithomyces chartarum spores were found in the pasture. Samples from a similar neighboring B. decumbens pasture grazed by cattle without photosensitization contained 1.63% of protodioscin isomers. Outbreaks of photosensitization caused by Brachiaria spp. are common in cattle in the Brazilian Cerrado (savanna) with about 51 million hectares of Brachiaria spp pastures. Sheep farming has been recently developed in this region, and the number of sheep is increasing significantly. Because sheep are more susceptible than cattle to lithogenic saponins, poisoning by Brachiaria should be an important limiting factor for the sheep industry.

Abstract in English:

ABSTRACT.- Amarante A.F.T., Rocha R.A. & Bricarello P.A. 2006. Relationship of intestinal histology with the resistance to Trichostrongylus colubriformis infection in three breeds of sheep. Pesquisa Veterinária Brasileira 26(1):43-48. Departamento de Parasitologia, Instituto de Biociências, Universidade Estadual Paulista (Unesp), Cx. Postal 510, Botucatu, SP 18618-000, Brazil. E-mail: amarante@ibb.unesp.br The study was carried out to evaluate the relationship of inflammatory intestinal cells with the resistance to Trichostrongylus colubriformis infections in three breeds of sheep (Santa Ines, Suffolk and Ile de France), naturally infected. Mast cells, eosinophils, and globule leucocytes were enumerated in intestinal mucosa. Histamine concentration was estimated in intestinal tissue samples and the length of male and female specimens were determined. The three breeds of sheep showed similar cellular response in the small intestine mucosa (P>0.05). There was extensive variation among sheep in the parasitological and inflammatory cell variables, even in lambs of the same breed. In general, animals presenting less inflammatory cells had a larger worm burden, higher fecal egg counts, and larger T. colubriformis worms. The inflammatory cells possibly impaired the parasite’s establishment, development, and survival.

• Sheep Trichostrongylus colubriformis resistance mast cells eosinophils

Abstract in Portuguese:

ABSTRACT.- Amarante A.F.T., Rocha R.A. & Bricarello P.A. 2006. Relationship of intestinal histology with the resistance to Trichostrongylus colubriformis infection in three breeds of sheep. Pesquisa Veterinária Brasileira 26(1):43-48. Departamento de Parasitologia, Instituto de Biociências, Universidade Estadual Paulista (Unesp), Cx. Postal 510, Botucatu, SP 18618-000, Brazil. E-mail: amarante@ibb.unesp.br The study was carried out to evaluate the relationship of inflammatory intestinal cells with the resistance to Trichostrongylus colubriformis infections in three breeds of sheep (Santa Ines, Suffolk and Ile de France), naturally infected. Mast cells, eosinophils, and globule leucocytes were enumerated in intestinal mucosa. Histamine concentration was estimated in intestinal tissue samples and the length of male and female specimens were determined. The three breeds of sheep showed similar cellular response in the small intestine mucosa (P>0.05). There was extensive variation among sheep in the parasitological and inflammatory cell variables, even in lambs of the same breed. In general, animals presenting less inflammatory cells had a larger worm burden, higher fecal egg counts, and larger T. colubriformis worms. The inflammatory cells possibly impaired the parasite’s establishment, development, and survival.

Abstract in English:

ABSTRACT.- Lucioli J., Furlan F.H., Mezaroba S., Bechtold S.L., Gava A. & Traverso S.D. 2007. [Acute sodium fluorsilicate poisoning in cattle in the state of Santa Catarina.] Intoxicação aguda por fluorsilicato de sódio em bovinos no Estado de Santa Catarina. Pesquisa Veterinária Brasileira 27(1):49-52. Laboratório de Patologia Animal, Departamento de Clínica e Patologia, Faculdade de Veterinária, UDESC, Avenida Luís de Camões 2090, Lages, SC 88520-000, Brazil. E-mail: a2sdt@cav.udesc.br An acute poisoning with sodium fluorsilicate in six cattle is reported, as well as the experimental reproduction by oral administration of the compound to two bovines. Clinical manifestations of the natural poisoning include muscle tremors, hypersalivation, groaning and rapid death. In the experimental poisoning lateral recumbency, dyspnea, tetanic spasms and paddling was also observed. The main necropsy findings were reddening, edema and ulceration of the ruminal and abomasal mucosa. Histopathological findings were necrosis of the epithelium of the forestomachs with polymorphonuclear infiltration of the submucosal and muscular layers. Tubular renal necrosis, liver portal necrosis and necrosis of the lymphoid tissues was also noted. The sodium fluorsilicate caused clinical signs at a dose of 300mg/kg, and death from 400mg/kg on.

• Sodium fluorsilicate poisoning cattle pathology

Abstract in Portuguese:

ABSTRACT.- Lucioli J., Furlan F.H., Mezaroba S., Bechtold S.L., Gava A. & Traverso S.D. 2007. [Acute sodium fluorsilicate poisoning in cattle in the state of Santa Catarina.] Intoxicação aguda por fluorsilicato de sódio em bovinos no Estado de Santa Catarina. Pesquisa Veterinária Brasileira 27(1):49-52. Laboratório de Patologia Animal, Departamento de Clínica e Patologia, Faculdade de Veterinária, UDESC, Avenida Luís de Camões 2090, Lages, SC 88520-000, Brazil. E-mail: a2sdt@cav.udesc.br An acute poisoning with sodium fluorsilicate in six cattle is reported, as well as the experimental reproduction by oral administration of the compound to two bovines. Clinical manifestations of the natural poisoning include muscle tremors, hypersalivation, groaning and rapid death. In the experimental poisoning lateral recumbency, dyspnea, tetanic spasms and paddling was also observed. The main necropsy findings were reddening, edema and ulceration of the ruminal and abomasal mucosa. Histopathological findings were necrosis of the epithelium of the forestomachs with polymorphonuclear infiltration of the submucosal and muscular layers. Tubular renal necrosis, liver portal necrosis and necrosis of the lymphoid tissues was also noted. The sodium fluorsilicate caused clinical signs at a dose of 300mg/kg, and death from 400mg/kg on.

Abstract in English:

ABSTRACT.- Almeida R.F.C., Madruga C.R., Soares C.O., Fernandes M.C., Carvalho N.M., Jorge K.S.G. & Osório A.L.A.R. 2006. [Specific immune response of cattle to experimental sensibilization by inactivated Mycobacterium bovis and Mycobacterium avium.] Resposta imune específica de bovinos experimentalmente sensibilizados com inóculos inativados de Mycobacterium bovis e Mycobacterium avium. Pesquisa Veterinária Brasileira 26(4):195-200. Departamento de Medicina Veterinária da Universidade Federal de Mato Grosso do Sul, Cidade Universitária, Campo Grande, MS 79070-900, Brazil. E-mail: analudmv@nin.ufms.br The presumptive diagnosis of bovine tuberculosis is based on analysis of the immune response to micobacterial antigens. This experimental simulation of sensibilization by Mycobacterium bovis and Mycobacterium avium in cattle aimed to verify the immune response by both the cervical comparative test and the evolution of the specific production of gamma-interferon, and also to identify interference of unspecified reactions by M. avium on the test results. The results support that the experimental animals started a response of delayed hypersensitivity to the inactivated bacilli, and that both diagnostic tests for bovine tuberculosis were efficient for the identification of animals sensitized with M. bovis and for discrimination of reactions generated by inoculation of cattle with M. avium.

• Mycobacterium bovis Mycobacterium avium gamma-interferon tuberculin immune response

Abstract in Portuguese:

ABSTRACT.- Almeida R.F.C., Madruga C.R., Soares C.O., Fernandes M.C., Carvalho N.M., Jorge K.S.G. & Osório A.L.A.R. 2006. [Specific immune response of cattle to experimental sensibilization by inactivated Mycobacterium bovis and Mycobacterium avium.] Resposta imune específica de bovinos experimentalmente sensibilizados com inóculos inativados de Mycobacterium bovis e Mycobacterium avium. Pesquisa Veterinária Brasileira 26(4):195-200. Departamento de Medicina Veterinária da Universidade Federal de Mato Grosso do Sul, Cidade Universitária, Campo Grande, MS 79070-900, Brazil. E-mail: analudmv@nin.ufms.br The presumptive diagnosis of bovine tuberculosis is based on analysis of the immune response to micobacterial antigens. This experimental simulation of sensibilization by Mycobacterium bovis and Mycobacterium avium in cattle aimed to verify the immune response by both the cervical comparative test and the evolution of the specific production of gamma-interferon, and also to identify interference of unspecified reactions by M. avium on the test results. The results support that the experimental animals started a response of delayed hypersensitivity to the inactivated bacilli, and that both diagnostic tests for bovine tuberculosis were efficient for the identification of animals sensitized with M. bovis and for discrimination of reactions generated by inoculation of cattle with M. avium.

Abstract in English:

ABSTRACT.- Monteiro L.A.R.C., Pellegrin A.O., Ishikawa M.M. & Osório A.L.A.R. 2006. [Epidemiological investigation of bovine brucellosis in an extract of Mato Grosso do Sul, Brazil.] Investigação epidemiológica da brucelose bovina em um estrato do Estado de Mato Grosso do Sul. Pesquisa Veterinária Brasileira 26(4):217-222. Programa Mestrado em Ciência Animal, Universidade Federal do Mato Grosso do Sul, Campo Grande, MS 79070-900, Brazil. E-mail: leticiacmonteiro@yahoo.com.br The study aimed to estimate the prevalence of bovine brucellosis in 22 counties which make up the region Extract 1 of the State of Mato Grosso do Sul, Brazil, in order to identify risk factors associated with the infection. The sample region encompasses an area of 70,214.1 km² and represents 19.7% of the State. The region studied has about 5.7 million head of cattle, corresponding to 23% of the total of 24.9 million cattle in the State of Mato Grosso do Sul. On 210 farms, between December 2003 and March 2004, 2,376 blood samples were collected from cows, aged 24 months or older, for serial diagnostic tests. Screening through the buffered acidified antigen test was confirmed by the 2-mercaptoetanol test. On the occasion of sample collection a questionnaire with information related to identification, kind of cattle and management practices was filled out. In individual animals the real prevalence was estimated at 5.6%, and in the cattle herds at 37.3%. The variables, which presented association through odds ratio (OR), univariate analysis and 95% confidence interval (CI) with serum positivity for brucellosis, were: the exploration of beef cattle (OR = 2.82, 95% CI = 1.49-5.34), Zebu breed (OR = 2.62, 95% CI = 1.40-4.88) and abortion (OR = 1.83, 95% CI = 1.01-3.33). The results shown here demonstrate, despite the prevalence of brucellosis in the extract of Mato Grosso do Sul studied, that the control of the disease may depend on adoption of a program focusing upon the exploration of beef cattle, the Zebu breed and the occurrence of abortion.

• Brucellosis cattle epidemiology seroprevalence

Abstract in Portuguese:

ABSTRACT.- Monteiro L.A.R.C., Pellegrin A.O., Ishikawa M.M. & Osório A.L.A.R. 2006. [Epidemiological investigation of bovine brucellosis in an extract of Mato Grosso do Sul, Brazil.] Investigação epidemiológica da brucelose bovina em um estrato do Estado de Mato Grosso do Sul. Pesquisa Veterinária Brasileira 26(4):217-222. Programa Mestrado em Ciência Animal, Universidade Federal do Mato Grosso do Sul, Campo Grande, MS 79070-900, Brazil. E-mail: leticiacmonteiro@yahoo.com.br The study aimed to estimate the prevalence of bovine brucellosis in 22 counties which make up the region Extract 1 of the State of Mato Grosso do Sul, Brazil, in order to identify risk factors associated with the infection. The sample region encompasses an area of 70,214.1 km² and represents 19.7% of the State. The region studied has about 5.7 million head of cattle, corresponding to 23% of the total of 24.9 million cattle in the State of Mato Grosso do Sul. On 210 farms, between December 2003 and March 2004, 2,376 blood samples were collected from cows, aged 24 months or older, for serial diagnostic tests. Screening through the buffered acidified antigen test was confirmed by the 2-mercaptoetanol test. On the occasion of sample collection a questionnaire with information related to identification, kind of cattle and management practices was filled out. In individual animals the real prevalence was estimated at 5.6%, and in the cattle herds at 37.3%. The variables, which presented association through odds ratio (OR), univariate analysis and 95% confidence interval (CI) with serum positivity for brucellosis, were: the exploration of beef cattle (OR = 2.82, 95% CI = 1.49-5.34), Zebu breed (OR = 2.62, 95% CI = 1.40-4.88) and abortion (OR = 1.83, 95% CI = 1.01-3.33). The results shown here demonstrate, despite the prevalence of brucellosis in the extract of Mato Grosso do Sul studied, that the control of the disease may depend on adoption of a program focusing upon the exploration of beef cattle, the Zebu breed and the occurrence of abortion.

Abstract in English:

ABSTRACT.- Santos S.B., Faccini J.L.H. & Santos A.C.G. 2006. [Seasonal variation of Bovicola caprae parasitizing goats in the State of Paraíba, northeastern Brazil.] Variação estacional de Bovicola caprae parasitando caprinos no Estado da Paraíba. Pesquisa Veterinária Brasileira 26(4):249-253. Departamento de Parasitologia Animal, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: faccini@ufrrj.br The effects of temperature, humidity and rainfall on field population trend of the biting louse Bovicola caprae, parasitizing goats bred in the semiarid region of the State of Paraiba, northeastern Brazil were monthly evaluated from August 1999 to July 2002. In the first two years (August 1999 to July 2001) 30 goats were examined, whereas 16 goats were examined in the last year (August 2001 to July 2002). All goats were crossbred, both sexes and abated for human consumption. The lice were collected in an area 4cm of diameter at three body sites: maxillary, back line and haunch. Spearman correlation analysis was conducted (p< 0.05) between monthly average intensity of infestation of all stages (egg, larva, nymph, male and female) of the life cycle pooled and monthly total counts of each stage and mean temperature, mean relative humidity and rainfall. B. caprae was found throughout the year with prevalence of 75-100%. Increase of the louse population during the drier months was probably a consequence of poor nutrition due to reduced pasture and inadequate husbandry practices instead the influence of abiotic factors.

• Bovicola caprae Trichodectidae Mallophaga seasonal variation goats northeastern Brazil

Abstract in Portuguese:

ABSTRACT.- Santos S.B., Faccini J.L.H. & Santos A.C.G. 2006. [Seasonal variation of Bovicola caprae parasitizing goats in the State of Paraíba, northeastern Brazil.] Variação estacional de Bovicola caprae parasitando caprinos no Estado da Paraíba. Pesquisa Veterinária Brasileira 26(4):249-253. Departamento de Parasitologia Animal, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: faccini@ufrrj.br The effects of temperature, humidity and rainfall on field population trend of the biting louse Bovicola caprae, parasitizing goats bred in the semiarid region of the State of Paraiba, northeastern Brazil were monthly evaluated from August 1999 to July 2002. In the first two years (August 1999 to July 2001) 30 goats were examined, whereas 16 goats were examined in the last year (August 2001 to July 2002). All goats were crossbred, both sexes and abated for human consumption. The lice were collected in an area 4cm of diameter at three body sites: maxillary, back line and haunch. Spearman correlation analysis was conducted (p< 0.05) between monthly average intensity of infestation of all stages (egg, larva, nymph, male and female) of the life cycle pooled and monthly total counts of each stage and mean temperature, mean relative humidity and rainfall. B. caprae was found throughout the year with prevalence of 75-100%. Increase of the louse population during the drier months was probably a consequence of poor nutrition due to reduced pasture and inadequate husbandry practices instead the influence of abiotic factors.

Abstract in English:

ABSTRACT.- Barbosa J.D., Oliveira C.M.C., Tokarnia C.H. & Peixoto P.V. 2006. [Hepatogenous photosensitization in horses caused by Brachiaria humidicola (Gramineae) in the State of Pará.] Fotossensibilização hepatógena em eqüinos pela ingestão de Brachiaria humidicola (Gramineae) no Estado do Pará. Pesquisa Veterinária Brasileira 26(3):147-153. Escola de Medicina Veterinária, Campus Castanhal, Universidade Federal do Pará, Rua Maximino Porpino 1000, Castanhal, PA 68743-080, Brazil. E-mail: diomedes@ufpa.br Data on the clinical-pathological aspects and on the epidemioloy of a disease in horses, characterized by phototsensitization, which occurs in northeastern of Pará, Brazil, are presented. Of a total of 40 horses examined clinically, post-mortem examination was performed on seven. Due to the characteristic lesions found on the non-pigmented skin, the macroscopic and histological alterations in the liver, and knowing that Brachiaria grasses contain saponins with toxic properties, which cause liver lesions and photosensitization in cattle and sheep, it is concluded that this disease in horses is caused by grassing exclusively Brachiaria humidicola.

• Poisonous plants Brachiaria humidicola plant poisoning photosensitization saponins horses

Abstract in Portuguese:

ABSTRACT.- Barbosa J.D., Oliveira C.M.C., Tokarnia C.H. & Peixoto P.V. 2006. [Hepatogenous photosensitization in horses caused by Brachiaria humidicola (Gramineae) in the State of Pará.] Fotossensibilização hepatógena em eqüinos pela ingestão de Brachiaria humidicola (Gramineae) no Estado do Pará. Pesquisa Veterinária Brasileira 26(3):147-153. Escola de Medicina Veterinária, Campus Castanhal, Universidade Federal do Pará, Rua Maximino Porpino 1000, Castanhal, PA 68743-080, Brazil. E-mail: diomedes@ufpa.br Data on the clinical-pathological aspects and on the epidemioloy of a disease in horses, characterized by phototsensitization, which occurs in northeastern of Pará, Brazil, are presented. Of a total of 40 horses examined clinically, post-mortem examination was performed on seven. Due to the characteristic lesions found on the non-pigmented skin, the macroscopic and histological alterations in the liver, and knowing that Brachiaria grasses contain saponins with toxic properties, which cause liver lesions and photosensitization in cattle and sheep, it is concluded that this disease in horses is caused by grassing exclusively Brachiaria humidicola.

Abstract in English:

ABSTRACT.- Guedes K.M.R., Schild A.L. Riet-Correa F., Barros S.S. & Simões S.V.D. 2006. [Spongious degeneration in the central nervous system in Sindhi calves]. Degeneração esponjosa no sistema nervoso central de bezerros da raça Sindhi. Pesquisa Veterinária Brasileira 26(3):157-160. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, Paraíba, Brazil. E-mail franklin.riet@pesquisador.cnpq.br Spongy degeneration (status spongiosus) includes many histological alterations characterized by vacuoles in the neuropile in different regions of the central nervous system (CNS). The vacuolization can be caused by intramyelinic edema, as in maple syrup urine disease and some toxic diseases, or by astrocytic edema, as in citrullinemia. This paper reports a spongy degeneration in two Sindhi calves, a female and a male. Both calves were offspring from the same bull, and the herd had high degree of inbreeding. The female calf was born normal, but progressive nervous signs were observed since 2 months old. The male calf had progressive nervous signs since it was born. Both calves were euthanized with severe nervous signs when 4 months old. At necropsy the liver was pale in the male calf. Histological alterations were mild to accentuated vacuolization, mainly in the deep cerebral cortex, cerebellar white matter, grey matter of the spinal cord, internal capsule, and brain stem. Fatty degeneration was observed in the liver of both animals. On electron microscopy it was found that the status spongiosus was caused by astrocytic edema. It is suggested that the disease is caused by a metabolic hereditary error.

• Status spongiosus astrocytic edema congenital diseases cattle

Abstract in Portuguese:

ABSTRACT.- Guedes K.M.R., Schild A.L. Riet-Correa F., Barros S.S. & Simões S.V.D. 2006. [Spongious degeneration in the central nervous system in Sindhi calves]. Degeneração esponjosa no sistema nervoso central de bezerros da raça Sindhi. Pesquisa Veterinária Brasileira 26(3):157-160. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, Paraíba, Brazil. E-mail franklin.riet@pesquisador.cnpq.br Spongy degeneration (status spongiosus) includes many histological alterations characterized by vacuoles in the neuropile in different regions of the central nervous system (CNS). The vacuolization can be caused by intramyelinic edema, as in maple syrup urine disease and some toxic diseases, or by astrocytic edema, as in citrullinemia. This paper reports a spongy degeneration in two Sindhi calves, a female and a male. Both calves were offspring from the same bull, and the herd had high degree of inbreeding. The female calf was born normal, but progressive nervous signs were observed since 2 months old. The male calf had progressive nervous signs since it was born. Both calves were euthanized with severe nervous signs when 4 months old. At necropsy the liver was pale in the male calf. Histological alterations were mild to accentuated vacuolization, mainly in the deep cerebral cortex, cerebellar white matter, grey matter of the spinal cord, internal capsule, and brain stem. Fatty degeneration was observed in the liver of both animals. On electron microscopy it was found that the status spongiosus was caused by astrocytic edema. It is suggested that the disease is caused by a metabolic hereditary error.

Abstract in English:

ABSTRACT.- Costa M.M., Machado S.A., Krewer C.C., Ilha M.R.S., Graça D.L., Guaraldi A.L.M. & Vargas A.C. 2006. Pathogenicity of Rhodococcus equi in mice, isolated from environment, human and horse clinical samples. Pesquisa Veterinária Brasileira 26(3):167-170. Laboratório de Bacteriologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, Avenida Roraima 1000, Santa Maria, RS 97105-900, Brazil. E-mail: agueda@ccr.ufsm.br Rhodococcus equi is a facultative intracellular pathogen associated with bronchopneumonia, mesenteric lymphadenitis and enterocolitis in foals. Although R. equi is likely to be found in every horse-breeding farm, the clinical disease is unrecognized in most of them. Capsule components, equi factor, micolic acid and some products encoded by the large 85-90Kb plasmid were described as virulence factors. However, the pathogenesis of R. equi infections and the sensibility of foals are not completely understood. The aim of this study was evaluate the virulence of R. equi isolated from human, horses and environment for mices. Nine strains carrying the 85-90Kb plasmid isolated from foal clinical specimens, one from immunodeficient human patient and six plasmidless strains (four isolated from feces, one from pasture and one from immunodeficient human patient) were inoculated in cyclophosphamide immunossuppressed mice. The pathological changes and viability of R. equi cells in the liver of mice was verified after the 3rd, 6th an 10th day after inoculation for horse and environmental isolates and for R. equi isolates from human patients on the 1st, 3rd and 6th day. During the necropsy procedures, infiltrate of macrophages and pyogranulomatous lesions were detected after the sixth pos-inoculation day in the liver and spleen. In horse isolates, only plasmid positive strains were virulent, but in human isolates both strains (plasmid positive e plasmid negative) were virulent. Both groups of the immunossupressed mice inoculated with R. equi isolated from environment showed pathological changes. All R. equi strains were unable to kill non imunossuppressed mice.

• Rhodococcus equi mice virulence cyclophosphamide

Abstract in Portuguese:

ABSTRACT.- Costa M.M., Machado S.A., Krewer C.C., Ilha M.R.S., Graça D.L., Guaraldi A.L.M. & Vargas A.C. 2006. Pathogenicity of Rhodococcus equi in mice, isolated from environment, human and horse clinical samples. Pesquisa Veterinária Brasileira 26(3):167-170. Laboratório de Bacteriologia, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, Avenida Roraima 1000, Santa Maria, RS 97105-900, Brazil. E-mail: agueda@ccr.ufsm.br Rhodococcus equi is a facultative intracellular pathogen associated with bronchopneumonia, mesenteric lymphadenitis and enterocolitis in foals. Although R. equi is likely to be found in every horse-breeding farm, the clinical disease is unrecognized in most of them. Capsule components, equi factor, micolic acid and some products encoded by the large 85-90Kb plasmid were described as virulence factors. However, the pathogenesis of R. equi infections and the sensibility of foals are not completely understood. The aim of this study was evaluate the virulence of R. equi isolated from human, horses and environment for mices. Nine strains carrying the 85-90Kb plasmid isolated from foal clinical specimens, one from immunodeficient human patient and six plasmidless strains (four isolated from feces, one from pasture and one from immunodeficient human patient) were inoculated in cyclophosphamide immunossuppressed mice. The pathological changes and viability of R. equi cells in the liver of mice was verified after the 3rd, 6th an 10th day after inoculation for horse and environmental isolates and for R. equi isolates from human patients on the 1st, 3rd and 6th day. During the necropsy procedures, infiltrate of macrophages and pyogranulomatous lesions were detected after the sixth pos-inoculation day in the liver and spleen. In horse isolates, only plasmid positive strains were virulent, but in human isolates both strains (plasmid positive e plasmid negative) were virulent. Both groups of the immunossupressed mice inoculated with R. equi isolated from environment showed pathological changes. All R. equi strains were unable to kill non imunossuppressed mice.