PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Almeida A.P.M.G., Kommers G.D., Nogueira A.P.A., Júnior L.G.B., Marques B.M.F.P. & Lemos R.A.A. 2006. [Evaluation of the toxicity of Leucaena leucocephala (Leg. Mimosoi-deae) in sheep.] Avaliação do efeito tóxico de Leucaena leucocephala (Leg.Mimosoideae) em ovinos. Pesquisa Veterinária Brasileira 26(3):190-194. Departamento de Medicina Veterinária, Faculdade de Medicina Vetetinária e Zootecnia, Universidade Federal de Mato Grosso do Sul, Av. Senador Filinto Müller 2443, Cx.Postal 549, Campo Grande, MS 79070-900, Brazil. E-mail: eqrural@nin.ufms.br An experiment was performed to evaluate the toxicity of Leucaena leucocephala for sheep. Two ewes and six lambs were divided into seven treatments and fed the plant. The adult ewes did not show clinical signs of poisoning. The 4 to 5-month-old lambs presented partial wool loss 6 days after beginning of the administration of the plant and total wool loss after 12 or 20 days. The age of the sheep in this experiment suggests resistance of adult ewes and susceptibility of young lambs to L. leucocaephala poisoning.

• Poisonous plants Leucaena leucocephala Leguminosae Mimosoideae plant poisoning sheep diseases pathology

Abstract in Portuguese:

ABSTRACT.- Almeida A.P.M.G., Kommers G.D., Nogueira A.P.A., Júnior L.G.B., Marques B.M.F.P. & Lemos R.A.A. 2006. [Evaluation of the toxicity of Leucaena leucocephala (Leg. Mimosoi-deae) in sheep.] Avaliação do efeito tóxico de Leucaena leucocephala (Leg.Mimosoideae) em ovinos. Pesquisa Veterinária Brasileira 26(3):190-194. Departamento de Medicina Veterinária, Faculdade de Medicina Vetetinária e Zootecnia, Universidade Federal de Mato Grosso do Sul, Av. Senador Filinto Müller 2443, Cx.Postal 549, Campo Grande, MS 79070-900, Brazil. E-mail: eqrural@nin.ufms.br An experiment was performed to evaluate the toxicity of Leucaena leucocephala for sheep. Two ewes and six lambs were divided into seven treatments and fed the plant. The adult ewes did not show clinical signs of poisoning. The 4 to 5-month-old lambs presented partial wool loss 6 days after beginning of the administration of the plant and total wool loss after 12 or 20 days. The age of the sheep in this experiment suggests resistance of adult ewes and susceptibility of young lambs to L. leucocaephala poisoning.

Abstract in English:

Abstract.- Brocchi M., Ferreira A., Lancellotti M., Stehling E.G., Campos T.A., Nakazato G., Pestana de Castro A.F. & Silveira W.D. 2006. Typing of avian pathogenic Escherichia coli strains by REP-PCR. Pesquisa Veterinária Brasileira 26(2):69-73. Departamento de Microbiologia e Imunologia, Instituto de Biologia, Universidade de Campinas, Cx. Postal 6109, Campinas, SP 13081-862, Brazil. E-mail: wds@unicamp.br In the present study the repetitive extragenic palindromic (REP) polymerase chain reaction (PCR) technique was used to establish the clonal variability of 49 avian Escherichia coli (APEC) strains isolated from different outbreak cases of septicemia (n=24), swollen head syndrome (n=14) and omphalitis (n=11). Thirty commensal strains isolated from poultry with no signs of these illnesses were used as control strains. The purified DNA of these strains produced electrophoretic profiles ranging from 0 to 15 bands with molecular sizes varying from 100 bp to 6.1 kb, allowing the grouping of the 79 strains into a dendrogram containing 49 REP-types. Although REP-PCR showed good discriminating power it was not able to group the strains either into specific pathogenic classes or to differentiate between pathogenic and non-pathogenic strains. On the contrary, we recently demonstrated that other techniques such as ERIC-PCR and isoenzyme profiles are appropriate to discriminate between commensal and APEC strains and also to group these strains into specific pathogenic classes. In conclusion, REP-PCR seems to be a technique neither efficient nor universal for APEC strains discrimination. However, the population clonal structure obtained with the use of REP-PCR must not be ignored particularly if one takes into account that the APEC pathogenic mechanisms are not completely understood yet.

• Avian Escherichia coli typing REP-PCR.

Abstract in Portuguese:

Abstract.- Brocchi M., Ferreira A., Lancellotti M., Stehling E.G., Campos T.A., Nakazato G., Pestana de Castro A.F. & Silveira W.D. 2006. Typing of avian pathogenic Escherichia coli strains by REP-PCR. Pesquisa Veterinária Brasileira 26(2):69-73. Departamento de Microbiologia e Imunologia, Instituto de Biologia, Universidade de Campinas, Cx. Postal 6109, Campinas, SP 13081-862, Brazil. E-mail: wds@unicamp.br In the present study the repetitive extragenic palindromic (REP) polymerase chain reaction (PCR) technique was used to establish the clonal variability of 49 avian Escherichia coli (APEC) strains isolated from different outbreak cases of septicemia (n=24), swollen head syndrome (n=14) and omphalitis (n=11). Thirty commensal strains isolated from poultry with no signs of these illnesses were used as control strains. The purified DNA of these strains produced electrophoretic profiles ranging from 0 to 15 bands with molecular sizes varying from 100 bp to 6.1 kb, allowing the grouping of the 79 strains into a dendrogram containing 49 REP-types. Although REP-PCR showed good discriminating power it was not able to group the strains either into specific pathogenic classes or to differentiate between pathogenic and non-pathogenic strains. On the contrary, we recently demonstrated that other techniques such as ERIC-PCR and isoenzyme profiles are appropriate to discriminate between commensal and APEC strains and also to group these strains into specific pathogenic classes. In conclusion, REP-PCR seems to be a technique neither efficient nor universal for APEC strains discrimination. However, the population clonal structure obtained with the use of REP-PCR must not be ignored particularly if one takes into account that the APEC pathogenic mechanisms are not completely understood yet.

Abstract in English:

ABSTRACT.- Barros R.R., Irigoyen L.F., Kommers G.D., Rech R.R., Fighera R.A. & Barros C.S.L. 2006. [Poisoning by Ramaria flavo-brunnescens (Clavariaceae) in cattle.] Intoxicação por Ramaria flavo-brunnescens (Clavariaceae) em bovinos. Pesquisa Veterinária Brasileira 26(2):87-96. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Two oubreaks of poisoning by the mushroom Ramaria flavo-brunnescens are reported in cattle from two farms located in the municipalities of Santa Maria and São Gabriel, state of Rio Grande do Sul, during April-May 2005. Out of a total of 180 yearling calves that had access to a pasture with eucalyptus woods, 19 were affected and 10 died. The clinical courses were 8-15 days and clinical signs included depression, weight loss, dehydration, drooling, loosening and loss of the long hairs of the tip of the tail, smoothening of the dorsal surface of the tongue with occasional ulceration, loosening of the corneal encasement of horns, hard and ball-shaped feces covered with a film of mucous, hypopion, hyphema and corneal opacity. Two calves had leucocytosis due to mild regenerative left shift. Nine calves were necropsied. Necropsy findings confirmed the clinical observation and additionaly included fibrinonecrotic esophagitis, mainly in the distal third of the esophageal mucosa. Histopathological changes in the skin of the tail included orthokeratotic hyperkeratosis; hair folicles with irregular contours, thickening of the tricolemmal keratin layer with occasional formation of keratin plugs, and degeneration and necrosis of the outer root sheath. At the laminar region of the hooves, there was hyperplasia of the top of epidermal laminae with irregular keratinization and retention of nuclei; several epidermal laminae were shortened and fused. There was hemorrhage, fibrin and neutrophilic infiltrate in the dermal laminae. In the mucosa of the tongue there was thinning of the covering epithelium, atrophy and loss of filiform papillae, multifocal areas of dyskeratosis, and spongiosis of the basal cell layer. In some parts the epithelium was lost and the surface consisted of granulation tissue and mixed inflammatory cell infiltrate. The esophageal mucosae of six calves had varying degree of epithelial necrosis and inflammation. The loss of the covering epithelium revealed an underneath area of granulation tissue with heavy inflammatory infiltrate composed predominantly of neutrophils and macrophages. In six calves there were focal symmetric bilateral areas of malacia observed at the level of obex in the medulla oblongata and affecting the white matter and parts of the dorsal nucleus of the vagus and of the hypoglossal nucleus. The epidemiology, clinical signs, pathology, and pathogenesis of poisoning by R. flavo-brunnescens in cattle are discussed.

• Poisonous plants Ramaria flavo-brunnescens Clavariaceae plant poisoning mushroom poisoning keratinization defect focal symmetric encephalomalacia diseases of cattle pathology.

Abstract in Portuguese:

ABSTRACT.- Barros R.R., Irigoyen L.F., Kommers G.D., Rech R.R., Fighera R.A. & Barros C.S.L. 2006. [Poisoning by Ramaria flavo-brunnescens (Clavariaceae) in cattle.] Intoxicação por Ramaria flavo-brunnescens (Clavariaceae) em bovinos. Pesquisa Veterinária Brasileira 26(2):87-96. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Two oubreaks of poisoning by the mushroom Ramaria flavo-brunnescens are reported in cattle from two farms located in the municipalities of Santa Maria and São Gabriel, state of Rio Grande do Sul, during April-May 2005. Out of a total of 180 yearling calves that had access to a pasture with eucalyptus woods, 19 were affected and 10 died. The clinical courses were 8-15 days and clinical signs included depression, weight loss, dehydration, drooling, loosening and loss of the long hairs of the tip of the tail, smoothening of the dorsal surface of the tongue with occasional ulceration, loosening of the corneal encasement of horns, hard and ball-shaped feces covered with a film of mucous, hypopion, hyphema and corneal opacity. Two calves had leucocytosis due to mild regenerative left shift. Nine calves were necropsied. Necropsy findings confirmed the clinical observation and additionaly included fibrinonecrotic esophagitis, mainly in the distal third of the esophageal mucosa. Histopathological changes in the skin of the tail included orthokeratotic hyperkeratosis; hair folicles with irregular contours, thickening of the tricolemmal keratin layer with occasional formation of keratin plugs, and degeneration and necrosis of the outer root sheath. At the laminar region of the hooves, there was hyperplasia of the top of epidermal laminae with irregular keratinization and retention of nuclei; several epidermal laminae were shortened and fused. There was hemorrhage, fibrin and neutrophilic infiltrate in the dermal laminae. In the mucosa of the tongue there was thinning of the covering epithelium, atrophy and loss of filiform papillae, multifocal areas of dyskeratosis, and spongiosis of the basal cell layer. In some parts the epithelium was lost and the surface consisted of granulation tissue and mixed inflammatory cell infiltrate. The esophageal mucosae of six calves had varying degree of epithelial necrosis and inflammation. The loss of the covering epithelium revealed an underneath area of granulation tissue with heavy inflammatory infiltrate composed predominantly of neutrophils and macrophages. In six calves there were focal symmetric bilateral areas of malacia observed at the level of obex in the medulla oblongata and affecting the white matter and parts of the dorsal nucleus of the vagus and of the hypoglossal nucleus. The epidemiology, clinical signs, pathology, and pathogenesis of poisoning by R. flavo-brunnescens in cattle are discussed.

Abstract in English:

ABSTRACT.- Coimbra H.S., Fernandes C.G., Soares M.P., Meireles M.C.A., Radamés R. & Schuch L.F.D. 2006. [Equine monocytic Ehrlichiosis in Rio Grande do Sul: clinical, pathological and epidemiological aspects.] Ehrlichiose monocítica eqüina no Rio Grande do Sul: aspectos clínicos, anátomo-patológicos e epidemiológicos. Pesquisa Veterinária Brasileira 26(2):97-101. Laboratório de Doenças Infecciosas, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário, Pelotas, RS 96010-900, Brazil. E-mail: bitoxu@ig.com.br A spontaneous outbreak of equine monocytic Ehrlichiosis (EME) is described. The disease occurred from November 2001 to February 2002 on a farm in the municipality of Arroio Grande, located at the western edge of the Mirim Lake, state of Rio Grande do Sul. Out of 50 horses 13 were affected and 6 died. The morbidity was 26% and the mortality 46.1%. The affected horses were 1-5 years old. The most important clinical sign was a profuse acute diarrhea. At necropsy of a horse that died with clinical signs of the disease, the main alterations were characterized by hemorrhagic areas of the mucosa of the large intestine with liquid contents, and congested and hemorrhagic areas alternating with normal areas as well as nodules with purulent secretion in the mucosa of the small intestine. The histological changes were characterized by moderate mononuclear infiltration of the mucosa, characterizing a lympho-histiocytic enteritis with predominance of macrophages. In the jejunum and ileum, related to the invagination of crypts and villi, a granulomatous enteritis was observed. To confirm the diagnosis of infection by Neorickettsia (Ehrlichia) risticii, blood samples of seven affected horses were taken and a polimerase chain reaction (PCR) was performed. Three tested blood samples were positive (42.8%) with observation of a band of 529pb characteristic of N. risticii.

• Neorickettsia (Ehrlichia) risticii equine monocytic Ehrlichiosis.

Abstract in Portuguese:

ABSTRACT.- Coimbra H.S., Fernandes C.G., Soares M.P., Meireles M.C.A., Radamés R. & Schuch L.F.D. 2006. [Equine monocytic Ehrlichiosis in Rio Grande do Sul: clinical, pathological and epidemiological aspects.] Ehrlichiose monocítica eqüina no Rio Grande do Sul: aspectos clínicos, anátomo-patológicos e epidemiológicos. Pesquisa Veterinária Brasileira 26(2):97-101. Laboratório de Doenças Infecciosas, Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário, Pelotas, RS 96010-900, Brazil. E-mail: bitoxu@ig.com.br A spontaneous outbreak of equine monocytic Ehrlichiosis (EME) is described. The disease occurred from November 2001 to February 2002 on a farm in the municipality of Arroio Grande, located at the western edge of the Mirim Lake, state of Rio Grande do Sul. Out of 50 horses 13 were affected and 6 died. The morbidity was 26% and the mortality 46.1%. The affected horses were 1-5 years old. The most important clinical sign was a profuse acute diarrhea. At necropsy of a horse that died with clinical signs of the disease, the main alterations were characterized by hemorrhagic areas of the mucosa of the large intestine with liquid contents, and congested and hemorrhagic areas alternating with normal areas as well as nodules with purulent secretion in the mucosa of the small intestine. The histological changes were characterized by moderate mononuclear infiltration of the mucosa, characterizing a lympho-histiocytic enteritis with predominance of macrophages. In the jejunum and ileum, related to the invagination of crypts and villi, a granulomatous enteritis was observed. To confirm the diagnosis of infection by Neorickettsia (Ehrlichia) risticii, blood samples of seven affected horses were taken and a polimerase chain reaction (PCR) was performed. Three tested blood samples were positive (42.8%) with observation of a band of 529pb characteristic of N. risticii.

Abstract in English:

ABSTRACT.- Rissi D.R., Oliveira F.N., Rech R.R., Pierezan F., Lemos R.A.A. & Barros C.S.L. 2006. [Epidemiology, clinical signs and distribution of the encephalic lesions in cattle affected by meningoencephalitis caused by bovine herpesvirus-5.] Epidemiologia, sinais clínicos e distribuição das lesões encefálicas em bovinos afetados por meningoencefalite por herpesvírus bovino-5. Pesquisa Veterinária Brasileira 26(2):123-132. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Seven outbreaks and an isolated case of meningoencephalitis caused by bovine herpesvirus-5 (BoHV-5) in cattle in Rio Grande do Sul, Brazil, occurring in 2002-2004, are described. From a total population at risk of 1,359 cattle, 54 1-18-month-old calves from both sexes and several breeds were affected and 50 died spontaneously or were euthanatized while moribund. The highest frequency of cases was in recently weaned calves or calves submitted to other stressing factors. General rates of morbidity, mortality and lethality were respectively 3.97, 3.67 and 92.59%. Clinical courses varied from 3-10 days and included depression, nasal and ocular discharge, grinding of teeth, circling, blindness, fever, nistagmus, trembling, anorexia, dysphagia, drooling, incoordination, head pressing, rough hair coat, tachycardia, tachypnea, abdominal pain, melena, falls, recumbency, opisthotonus, convulsions and paddling. Nineteen calves were necropsied. Necropsy findings were characterized by hyperemia of leptomeninges, swollen rostral portions of the telencephalon, and flattening of frontal lobes gyri; frequently in these frontal areas there were segmental brown-yellow discoloration and softening (malacia) of the cortex. In cases with more protracted clinical courses there were extensive swelling, softening and hemorrhaging of the telencephalic frontal lobes. Microscopically, all affected cattle had a necrotizing non-suppurative meningoencephalitis with variable distribution among the 19 cases and among the various telencephalic regions of the same case. The severity of these changes were more marked, in decreasing order of intensity, in the telencephalic frontal cortex, basal ganglia (nuclei), thalamus, brain stem, parietal telencephalic cortex, occipital telencephalic cortex and cerebellum. Perivascular inflammatory infiltrate consisted predominantly of lymphocytes, plasm cells, and less frequently of neutrophils. Additional microscopic findings included variable degrees of gliosis, edema, neuronal necrosis in the telencephalic cortex characterized by shrinking and eosinophilia of perikaria and nuclear picnosis (red neuron); basophilic intranuclear inclusion bodies in astrocytes and neurons (21.05% of the cases); sattelitosis; and neuronophagia. The areas of softening in the cortical substance consisted of necrosis of the neuroctodermal elements with maintenance of mesenchymal structures (vessels and microglia), infiltrate of Gitter cells, and, in more severe cases, extensive hemorrhages. In chronic cases, only vascular structures and a few Gitter cells remained in the cortical area leaving a cavity between white matter and leptomeninges (residual lesion).

• Bovine herpesvirus-5 BoHV-5 encephalitis diseases of cattle viral diseases neuropathology.

Abstract in Portuguese:

ABSTRACT.- Rissi D.R., Oliveira F.N., Rech R.R., Pierezan F., Lemos R.A.A. & Barros C.S.L. 2006. [Epidemiology, clinical signs and distribution of the encephalic lesions in cattle affected by meningoencephalitis caused by bovine herpesvirus-5.] Epidemiologia, sinais clínicos e distribuição das lesões encefálicas em bovinos afetados por meningoencefalite por herpesvírus bovino-5. Pesquisa Veterinária Brasileira 26(2):123-132. Departamento de Patologia, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Seven outbreaks and an isolated case of meningoencephalitis caused by bovine herpesvirus-5 (BoHV-5) in cattle in Rio Grande do Sul, Brazil, occurring in 2002-2004, are described. From a total population at risk of 1,359 cattle, 54 1-18-month-old calves from both sexes and several breeds were affected and 50 died spontaneously or were euthanatized while moribund. The highest frequency of cases was in recently weaned calves or calves submitted to other stressing factors. General rates of morbidity, mortality and lethality were respectively 3.97, 3.67 and 92.59%. Clinical courses varied from 3-10 days and included depression, nasal and ocular discharge, grinding of teeth, circling, blindness, fever, nistagmus, trembling, anorexia, dysphagia, drooling, incoordination, head pressing, rough hair coat, tachycardia, tachypnea, abdominal pain, melena, falls, recumbency, opisthotonus, convulsions and paddling. Nineteen calves were necropsied. Necropsy findings were characterized by hyperemia of leptomeninges, swollen rostral portions of the telencephalon, and flattening of frontal lobes gyri; frequently in these frontal areas there were segmental brown-yellow discoloration and softening (malacia) of the cortex. In cases with more protracted clinical courses there were extensive swelling, softening and hemorrhaging of the telencephalic frontal lobes. Microscopically, all affected cattle had a necrotizing non-suppurative meningoencephalitis with variable distribution among the 19 cases and among the various telencephalic regions of the same case. The severity of these changes were more marked, in decreasing order of intensity, in the telencephalic frontal cortex, basal ganglia (nuclei), thalamus, brain stem, parietal telencephalic cortex, occipital telencephalic cortex and cerebellum. Perivascular inflammatory infiltrate consisted predominantly of lymphocytes, plasm cells, and less frequently of neutrophils. Additional microscopic findings included variable degrees of gliosis, edema, neuronal necrosis in the telencephalic cortex characterized by shrinking and eosinophilia of perikaria and nuclear picnosis (red neuron); basophilic intranuclear inclusion bodies in astrocytes and neurons (21.05% of the cases); sattelitosis; and neuronophagia. The areas of softening in the cortical substance consisted of necrosis of the neuroctodermal elements with maintenance of mesenchymal structures (vessels and microglia), infiltrate of Gitter cells, and, in more severe cases, extensive hemorrhages. In chronic cases, only vascular structures and a few Gitter cells remained in the cortical area leaving a cavity between white matter and leptomeninges (residual lesion).

Abstract in English:

Batista J.S., Riet-Correa F., Barbosa R.C. & Guerra J.L. 2006. [Experimental infection by Trypanosoma vivax in sheep.] Infecção experimental por Trypanosoma vivax em ovinos. Pesquisa Veterinária Brasileira 26(1):31-37. Hospital Veterinário, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, PB, Brazil. E-mail: franklin.riet@pesquisador.cnpq.br This paper has the objective to report clinical signs, hematologic changes, and macroscopic and microscopic alterations in sheep infected experimentally with Trypanosoma vivax, isolated from an outbreak in cattle in the semiarid region of the state of Paraíba, northeastern Brazil. Four Santa Inês sheep were inoculated intravenously with 1ml of blood containing 1.85x105 trypomastigotes. Other 4 sheep were used as control. The presence of trypanosomes in the blood and the temperature were recorded daily during the first 30 days and fortnightly from day 31 to day 90 after infection. Also fortnightly, the sheep were weighed and blood samples were obtained for hematological analysis. One inoculated sheep died 75 days after inoculation. The other 3 inoculated and the 4 control sheep were killed 90 days after the beginning of the experiment. T. vivax was observed constantly in the blood of the inoculated sheep from 4-15 days after inoculation. From day 16 to day 30 the parasitemia was lower and irregular. No trypanosomes were observed in the blood after 30 days of infection. A positive linear correlation [Y=0.027x + 38.515, R2=0.944 (P<0.05)] was found between the number of trypanosomes in the blood and body temperature. Significant differences were observed in body weight between inoculated and non-inoculated sheep from day 30 to day 90 after the experiment. From day 30 to day 90 after inoculation trypanosomes were absent or only in low numbers in the blood, and the animals showed anemia and leucopenia. Gross alterations were pale carcasses, enlarged lymph nodes and spleen, and augmented liquid in the peritoneal and pericardiac cavities. Multifocal lymphocytic myocarditis was observed histologically. It is concluded that the isolate is pathogenic to sheep. It is suggested that the semiarid region, where the outbreak occurred, is non-endemic (marginal) for trypanosomosis, and that the disease may occur if the parasite is introduced through vectors.

• Experimental infection Trypanosoma vivax sheep semiarid.

Abstract in Portuguese:

Batista J.S., Riet-Correa F., Barbosa R.C. & Guerra J.L. 2006. [Experimental infection by Trypanosoma vivax in sheep.] Infecção experimental por Trypanosoma vivax em ovinos. Pesquisa Veterinária Brasileira 26(1):31-37. Hospital Veterinário, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, PB, Brazil. E-mail: franklin.riet@pesquisador.cnpq.br This paper has the objective to report clinical signs, hematologic changes, and macroscopic and microscopic alterations in sheep infected experimentally with Trypanosoma vivax, isolated from an outbreak in cattle in the semiarid region of the state of Paraíba, northeastern Brazil. Four Santa Inês sheep were inoculated intravenously with 1ml of blood containing 1.85x105 trypomastigotes. Other 4 sheep were used as control. The presence of trypanosomes in the blood and the temperature were recorded daily during the first 30 days and fortnightly from day 31 to day 90 after infection. Also fortnightly, the sheep were weighed and blood samples were obtained for hematological analysis. One inoculated sheep died 75 days after inoculation. The other 3 inoculated and the 4 control sheep were killed 90 days after the beginning of the experiment. T. vivax was observed constantly in the blood of the inoculated sheep from 4-15 days after inoculation. From day 16 to day 30 the parasitemia was lower and irregular. No trypanosomes were observed in the blood after 30 days of infection. A positive linear correlation [Y=0.027x + 38.515, R2=0.944 (P<0.05)] was found between the number of trypanosomes in the blood and body temperature. Significant differences were observed in body weight between inoculated and non-inoculated sheep from day 30 to day 90 after the experiment. From day 30 to day 90 after inoculation trypanosomes were absent or only in low numbers in the blood, and the animals showed anemia and leucopenia. Gross alterations were pale carcasses, enlarged lymph nodes and spleen, and augmented liquid in the peritoneal and pericardiac cavities. Multifocal lymphocytic myocarditis was observed histologically. It is concluded that the isolate is pathogenic to sheep. It is suggested that the semiarid region, where the outbreak occurred, is non-endemic (marginal) for trypanosomosis, and that the disease may occur if the parasite is introduced through vectors.

Abstract in English:

Simões S.V.D., Costa R.G., Souza P.M., Medeiros A.N. & Vilar A.L.T. 2005. [Passive immunity, neonatal morbidity and performance of kids in different colostrum management.] Imunidade passiva, morbidade neonatal e desempenho de cabritos em diferentes manejos de colostro. Pesquisa Veterinária Brasileira 25(4):219-224. Centro de Ciências Agrárias, UFPB, Campus III, Areia, PB 58397-000, Brazil. E-mail: saravilar@bol.com.br The experiment was performed to determine the kid management that ensures the best passive immunity, and to evaluate the relationship between passive immunity, neonatal morbidity and performance. Blood samples were obtained from 58 Saanen kids before colostrum ingestion and 30h after. The kids were submitted to five treatments: (T1) kids were allowed to nurse the dam for 24 hours ingesting colostrum ad libitum; (T2) kids were bottle-fed with 200mL colostrum in the first hour of life; (T3) kids were bottle-fed with 400 mL colostrum, 200mL in the first hour and 200mL 8 hours after birth; (T4) kids were bottle-fed with 400mL colostrum, 200mL in the first hour and 200mL 14 hours after birth; (T5) kids were bottle-fed with 600mL of colostrum, 200mL in the first hour, 200ml 12 hours after birth, and 200mL at 24 hours of life. Serum levels of gamaglobulins were determined by electrophoresis. The occurrence of diseases was monitored from birth to 28 days. Daily weight gains were used to evaluate the performance until weaning. The lowest concentration of g-globulin was observed in Group 2 (1,57g/dL) and the highest in Group 3 (2,60g/dL). In spite of higher levels of passive immunity Group 3 showed more animals with scours, however no statistical differences were observed. The immune status at 30 hours postpartum was not associated with neonatal weight gain.

• Immunity immunoglobulins colostrum neonatal morbidity performance kids.

Abstract in Portuguese:

Simões S.V.D., Costa R.G., Souza P.M., Medeiros A.N. & Vilar A.L.T. 2005. [Passive immunity, neonatal morbidity and performance of kids in different colostrum management.] Imunidade passiva, morbidade neonatal e desempenho de cabritos em diferentes manejos de colostro. Pesquisa Veterinária Brasileira 25(4):219-224. Centro de Ciências Agrárias, UFPB, Campus III, Areia, PB 58397-000, Brazil. E-mail: saravilar@bol.com.br The experiment was performed to determine the kid management that ensures the best passive immunity, and to evaluate the relationship between passive immunity, neonatal morbidity and performance. Blood samples were obtained from 58 Saanen kids before colostrum ingestion and 30h after. The kids were submitted to five treatments: (T1) kids were allowed to nurse the dam for 24 hours ingesting colostrum ad libitum; (T2) kids were bottle-fed with 200mL colostrum in the first hour of life; (T3) kids were bottle-fed with 400 mL colostrum, 200mL in the first hour and 200mL 8 hours after birth; (T4) kids were bottle-fed with 400mL colostrum, 200mL in the first hour and 200mL 14 hours after birth; (T5) kids were bottle-fed with 600mL of colostrum, 200mL in the first hour, 200ml 12 hours after birth, and 200mL at 24 hours of life. Serum levels of gamaglobulins were determined by electrophoresis. The occurrence of diseases was monitored from birth to 28 days. Daily weight gains were used to evaluate the performance until weaning. The lowest concentration of g-globulin was observed in Group 2 (1,57g/dL) and the highest in Group 3 (2,60g/dL). In spite of higher levels of passive immunity Group 3 showed more animals with scours, however no statistical differences were observed. The immune status at 30 hours postpartum was not associated with neonatal weight gain.

Abstract in English:

Lima V.M.F., Biazzono L., Silva A.C., Correa A.P.F.L. & Luvizotto M.C.R. 2005. Serological diagnosis of visceral leishmaniasis by an enzyme immunoassay using protein A in naturally infected dogs. Pesquisa Veterinária Brasileira 25(4):215-218. Departamento de Clínica, Cirurgia e Reprodução Animal, Faculdade de Medicina Veterinária, Universidade Estadual Paulista, Rua Clóvis Pestana 793, Araçatuba, SP 16050-680, Brazil. E-mail: vmflima@fmva.unesp.br A rapid indirect enzyme-linked immunosorbent assay (ELISA) was developed for measuring antibodies against Leishmania chagasi using total antigen from lysed promastigotes. Fifty symptomatic mixed breed dogs from a region of high incidence of visceral leishmaniasis in Brazil were examined. The results showed that in the positive animals, diagnosed by cytological examination, the ELISA using protein A assay system (mean optical density ± SD / 2.078 ± 0.631) detected more antibodies than the anti-IgG assay (mean optical density ± SD / 1.008 ± 0.437), while in the negative animals, the results by both systems were similar. These results suggest that the ELISA assay using protein A peroxidase conjugated could be useful to detect early infected animals in endemic areas, and thus help to control the spread of the infection.

• Leishmania chagasi visceral leishmaniasis protein A dogs.

Abstract in Portuguese:

Lima V.M.F., Biazzono L., Silva A.C., Correa A.P.F.L. & Luvizotto M.C.R. 2005. Serological diagnosis of visceral leishmaniasis by an enzyme immunoassay using protein A in naturally infected dogs. Pesquisa Veterinária Brasileira 25(4):215-218. Departamento de Clínica, Cirurgia e Reprodução Animal, Faculdade de Medicina Veterinária, Universidade Estadual Paulista, Rua Clóvis Pestana 793, Araçatuba, SP 16050-680, Brazil. E-mail: vmflima@fmva.unesp.br A rapid indirect enzyme-linked immunosorbent assay (ELISA) was developed for measuring antibodies against Leishmania chagasi using total antigen from lysed promastigotes. Fifty symptomatic mixed breed dogs from a region of high incidence of visceral leishmaniasis in Brazil were examined. The results showed that in the positive animals, diagnosed by cytological examination, the ELISA using protein A assay system (mean optical density ± SD / 2.078 ± 0.631) detected more antibodies than the anti-IgG assay (mean optical density ± SD / 1.008 ± 0.437), while in the negative animals, the results by both systems were similar. These results suggest that the ELISA assay using protein A peroxidase conjugated could be useful to detect early infected animals in endemic areas, and thus help to control the spread of the infection.

Abstract in English:

Rodrigues A., Fighera R.A., Souza T.M., Schild A.L., Soares M.P., Milano J. & Barros C.S.L. 2005. [Outbreaks of trypanosomiasis in horses by Trypanosoma evansi in the state of Rio Grande do Sul, Brazil: epidemiological, clinical, hematological, and pathological aspects.] Surtos de tripanossomíase por Trypanosoma evansi em eqüinos no Rio Grande do Sul: aspectos epidemiológicos, clínicos, hematológicos e patológicos. Pesquisa Veterinária Brasileira 25(4):239-249. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Cases of trypanosomiasis by Trypanosoma evansi were diagnosed in horses in the state of Rio Grande do Sul, Brazil, between 2003 and 2004. In one stud farm (Farm A) with 125 horses, 52 died. Additionally, around 80 mares were sent to Farm A to be bred. Of those, 66 became ill and 56 died after being returned to their farms of origin. Twenty one horses clinically affected by the disease were observed. Clinical signs included loss of weight (despite voracious appetite), lethargy, incoordination and instability of hindlimbs, atrophy of the large muscles of the hindlimbs, muscle weakness and paleness of mucosae. Specimens of T. evansi were detected in the blood drawn from four affected horses. Normocytic normochromic anemia with PCVs ranging from 15 to 31%, leucocytosis due to lymphocytosis associated to large atypical lymphocytes was observed in several affected horses. High levels of antibodies against T. evansi were detected in the serum of six horses from Farm A. Eight horses presented encephalic neurological signs such as circling, ataxia, blindness, excitation, falls, listlessness, proprioception deficits and head tilt. One horse assumed a “dog-seating position”. Necropsy findings included muscle atrophy, enlargement and lymphoid hyperplasia of the spleen and lymphnodes, edema and softening of the white and grey matter of the brain. Histologically, an overwhelming necrotizing panencephalitis was observed in the seven horses with encephalic signs. This panencephalitis was characterized by marked edema, demyelination and necrosis and perivascular infiltrates of 6-10 layers of lymphocytes and plasm cells affecting both the white and gray matter. Several plasm cells in the inflammatory infiltrate contained numerous eosinophilic globules in their cytoplasm (Mott cells). Similar histological lesions were observed in the spinal cord of the horse with the “dog-seating position”. The brains of five horses with the encephalic signs were submitted to immunohistochemistry stain by the streptavidin-biotin technique. In all of those five brains moderate to abundant specimens of T. evansi in the perivascular spaces and neuropile were marked by the specific antibody. Epidemiological, clinical, hematological, and pathological aspects of equine trypanosomiasis caused by T. evansi are discussed.

• Trypanosomiasis Trypanosoma evansi infectious diseases encephalitis hematology pathology diseases of horses.

Abstract in Portuguese:

Rodrigues A., Fighera R.A., Souza T.M., Schild A.L., Soares M.P., Milano J. & Barros C.S.L. 2005. [Outbreaks of trypanosomiasis in horses by Trypanosoma evansi in the state of Rio Grande do Sul, Brazil: epidemiological, clinical, hematological, and pathological aspects.] Surtos de tripanossomíase por Trypanosoma evansi em eqüinos no Rio Grande do Sul: aspectos epidemiológicos, clínicos, hematológicos e patológicos. Pesquisa Veterinária Brasileira 25(4):239-249. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Cases of trypanosomiasis by Trypanosoma evansi were diagnosed in horses in the state of Rio Grande do Sul, Brazil, between 2003 and 2004. In one stud farm (Farm A) with 125 horses, 52 died. Additionally, around 80 mares were sent to Farm A to be bred. Of those, 66 became ill and 56 died after being returned to their farms of origin. Twenty one horses clinically affected by the disease were observed. Clinical signs included loss of weight (despite voracious appetite), lethargy, incoordination and instability of hindlimbs, atrophy of the large muscles of the hindlimbs, muscle weakness and paleness of mucosae. Specimens of T. evansi were detected in the blood drawn from four affected horses. Normocytic normochromic anemia with PCVs ranging from 15 to 31%, leucocytosis due to lymphocytosis associated to large atypical lymphocytes was observed in several affected horses. High levels of antibodies against T. evansi were detected in the serum of six horses from Farm A. Eight horses presented encephalic neurological signs such as circling, ataxia, blindness, excitation, falls, listlessness, proprioception deficits and head tilt. One horse assumed a “dog-seating position”. Necropsy findings included muscle atrophy, enlargement and lymphoid hyperplasia of the spleen and lymphnodes, edema and softening of the white and grey matter of the brain. Histologically, an overwhelming necrotizing panencephalitis was observed in the seven horses with encephalic signs. This panencephalitis was characterized by marked edema, demyelination and necrosis and perivascular infiltrates of 6-10 layers of lymphocytes and plasm cells affecting both the white and gray matter. Several plasm cells in the inflammatory infiltrate contained numerous eosinophilic globules in their cytoplasm (Mott cells). Similar histological lesions were observed in the spinal cord of the horse with the “dog-seating position”. The brains of five horses with the encephalic signs were submitted to immunohistochemistry stain by the streptavidin-biotin technique. In all of those five brains moderate to abundant specimens of T. evansi in the perivascular spaces and neuropile were marked by the specific antibody. Epidemiological, clinical, hematological, and pathological aspects of equine trypanosomiasis caused by T. evansi are discussed.

Abstract in English:

Soto P., Echevarría H.M., Monteavaro C.E. & Catena M.C. 2005. Experimentally induced intravaginal Tritrichomonas foetus infection in a mouse model. Pesquisa Veterinária Brasileira 25(4):225-230. Laboratory of Clinical and Experimental Microbiology, Facultad de Ciencias Veterinarias, UNCPBA, Pinto 399, Tandil (7000), Buenos Aires, Argentina. E-mail: psoto@vet.unicen.ar The interest to develop research on the host-parasite relationship in bovine tritrichomonosis has accomplished the use of experimental models alternative to cattle. The BALB/c mouse became the most appropriate species susceptible to vaginal Tritrichomonas foetus infection requiring previous estrogenization. For the need of an experimental model without persistent estrogenization and with normal estrous cycles, the establishment and persistence of vaginal infection on BALB/c mouse with different concentrations of T. foetus in two experimental groups was evaluated. Group A was treated with 5mg of b-estradiol 3-benzoate to synchronize the estrous, 48 hours before the T. foetus vaginal inoculation, and Group B was inoculated in natural estrus. At 5-7 days after treatment, estrogenic effect decreased allowing all animals to cycle regularly during the experiment. From the first week post-infection, samples of vaginal mucus were taken from all animals during 34 weeks, in order to evaluate the course of infection and the stage of the estrus cycle. Group A showed 93.6% of infected animals, and Group B showed 38%. Different doses of T. foetus were assayed to establish the vaginal infection, with a persistence of 34 weeks. Although different behavior was observed in each subgroup belonging to either Group A or Group B, there were no significant differences among the infecting doses used. The b-estradiol 3-benzoate treatment had a favorable effect on the establishment of the infection (P<0.0001), but it did not influence its persistence (P=0.1097). According to the results, an experimental mouse model is presented, appropriate for further studies on mechanisms of pathogenicity, immune response, protective evaluation of immunogen and therapeutic effect of drugs.

• Tritrichomonas foetus mouse model experimental tritrichomonosis.

Abstract in Portuguese:

Soto P., Echevarría H.M., Monteavaro C.E. & Catena M.C. 2005. Experimentally induced intravaginal Tritrichomonas foetus infection in a mouse model. Pesquisa Veterinária Brasileira 25(4):225-230. Laboratory of Clinical and Experimental Microbiology, Facultad de Ciencias Veterinarias, UNCPBA, Pinto 399, Tandil (7000), Buenos Aires, Argentina. E-mail: psoto@vet.unicen.ar The interest to develop research on the host-parasite relationship in bovine tritrichomonosis has accomplished the use of experimental models alternative to cattle. The BALB/c mouse became the most appropriate species susceptible to vaginal Tritrichomonas foetus infection requiring previous estrogenization. For the need of an experimental model without persistent estrogenization and with normal estrous cycles, the establishment and persistence of vaginal infection on BALB/c mouse with different concentrations of T. foetus in two experimental groups was evaluated. Group A was treated with 5mg of b-estradiol 3-benzoate to synchronize the estrous, 48 hours before the T. foetus vaginal inoculation, and Group B was inoculated in natural estrus. At 5-7 days after treatment, estrogenic effect decreased allowing all animals to cycle regularly during the experiment. From the first week post-infection, samples of vaginal mucus were taken from all animals during 34 weeks, in order to evaluate the course of infection and the stage of the estrus cycle. Group A showed 93.6% of infected animals, and Group B showed 38%. Different doses of T. foetus were assayed to establish the vaginal infection, with a persistence of 34 weeks. Although different behavior was observed in each subgroup belonging to either Group A or Group B, there were no significant differences among the infecting doses used. The b-estradiol 3-benzoate treatment had a favorable effect on the establishment of the infection (P<0.0001), but it did not influence its persistence (P=0.1097). According to the results, an experimental mouse model is presented, appropriate for further studies on mechanisms of pathogenicity, immune response, protective evaluation of immunogen and therapeutic effect of drugs.