PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

Zlotowski P., Nakazato L., Dutra V., Barros S.S., Gimeno E.J., Göcks M., Colodel E.M. & Driemeier D. 2005. [Inherited glycogenosis in Brahman cattle in Brazil.] Glicogenose hereditária em bovinos Brahman no Brasil. Pesquisa Veterinária Brasileira 25(4):210-214. Setor de Patologia Veterinária, Departamento de Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Bairro Agronomia, Cx. Postal 15094, Porto Alegre, RS 91540-000. Brazil. E-mail: davetpat@ufrgs.br An inherited disease of cattle, characterized by lysosomal storage of glycogen in several tissues, is reported. The disease was diagnosed in a Brahman herd in the municipality of Porto Lucena, Rio Grande do Sul, Brazil. Affected calves, after one month of age, showed progressive difficulty to follow their mother, retarded growth, muscular weakness and tremors, lethargy and poor body condition. All affected calves were sired by the same bull. Necropsy was performed on three affected calves. The only gross lesion detected was paleness of the skeletal muscles of the trunk and limbs. Cytoplasmic vacuoles, the main histological lesion, were particularly evident in skeletal muscles, myocardium and Purkinje fibers, in neurons of the brain and spinal cord. Large amounts of periodic acid Schiff (PAS) positive granules were also observed in these most severely affected tissues. Pretreatment with diastase completely abolished the PAS reactivity. The 1057?TA, a lethal mutation in the gene of the acid alpha-glucosidase, which causes generalized glycogenosis in Brahman cattle, was detected by PCR in paraffin embedded tissues of affected animals on which post-mortem examination was performed. Clinical, histological and molecular findings were similar to previous descriptions of generalized glycogenosis in Brahman cattle in Australia. No previous indexed reports about generalized glycogenosis of Brahman cattle in Brazil could be found.

• Glycogenosis inherited disease Brahman cattle.

Abstract in Portuguese:

Zlotowski P., Nakazato L., Dutra V., Barros S.S., Gimeno E.J., Göcks M., Colodel E.M. & Driemeier D. 2005. [Inherited glycogenosis in Brahman cattle in Brazil.] Glicogenose hereditária em bovinos Brahman no Brasil. Pesquisa Veterinária Brasileira 25(4):210-214. Setor de Patologia Veterinária, Departamento de Patologia Clínica Veterinária, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Bairro Agronomia, Cx. Postal 15094, Porto Alegre, RS 91540-000. Brazil. E-mail: davetpat@ufrgs.br An inherited disease of cattle, characterized by lysosomal storage of glycogen in several tissues, is reported. The disease was diagnosed in a Brahman herd in the municipality of Porto Lucena, Rio Grande do Sul, Brazil. Affected calves, after one month of age, showed progressive difficulty to follow their mother, retarded growth, muscular weakness and tremors, lethargy and poor body condition. All affected calves were sired by the same bull. Necropsy was performed on three affected calves. The only gross lesion detected was paleness of the skeletal muscles of the trunk and limbs. Cytoplasmic vacuoles, the main histological lesion, were particularly evident in skeletal muscles, myocardium and Purkinje fibers, in neurons of the brain and spinal cord. Large amounts of periodic acid Schiff (PAS) positive granules were also observed in these most severely affected tissues. Pretreatment with diastase completely abolished the PAS reactivity. The 1057?TA, a lethal mutation in the gene of the acid alpha-glucosidase, which causes generalized glycogenosis in Brahman cattle, was detected by PCR in paraffin embedded tissues of affected animals on which post-mortem examination was performed. Clinical, histological and molecular findings were similar to previous descriptions of generalized glycogenosis in Brahman cattle in Australia. No previous indexed reports about generalized glycogenosis of Brahman cattle in Brazil could be found.

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:

Tancredi M.G.F., Faccini J.L.H., Tancredi I.P., Martins I.V.F. & Scott F.B. 2005. [The host-relationship between Psoroptes equi and horses.] Relação parasito-hospedeiro entre Psoroptes equi e eqüinos. Pesquisa Veterinária Brasileira 25(4):207-209. Departamento de Parasitologia Animal, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: faccini@ufrrj.br Horses, abandoned by their owners (stray horses) along the main roads in the state of Rio de Janeiro, southeastern Brazil, and brought by the Federal Police to a quarantine station at the Universidade Federal Rural do Rio de Janeiro, were included in the study. A total of 1,121 horses were examined from November 1998 to November 2000. Skin scrapings from 107 (9.5%) horses with signs of psoroptic mange resulted in 37 (34.6%) positive animals for Psoroptes equi. There was no statistical correlation between prevalence and host age or sex (c2, p>0,05). P. equi was diagnosed in animals with different hair color. The dorsal region (withers to hip) was the most affected area of the body.

• Psoroptes equi Acari Psoroptidae mange horses Brazil.

Abstract in Portuguese:

Tancredi M.G.F., Faccini J.L.H., Tancredi I.P., Martins I.V.F. & Scott F.B. 2005. [The host-relationship between Psoroptes equi and horses.] Relação parasito-hospedeiro entre Psoroptes equi e eqüinos. Pesquisa Veterinária Brasileira 25(4):207-209. Departamento de Parasitologia Animal, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: faccini@ufrrj.br Horses, abandoned by their owners (stray horses) along the main roads in the state of Rio de Janeiro, southeastern Brazil, and brought by the Federal Police to a quarantine station at the Universidade Federal Rural do Rio de Janeiro, were included in the study. A total of 1,121 horses were examined from November 1998 to November 2000. Skin scrapings from 107 (9.5%) horses with signs of psoroptic mange resulted in 37 (34.6%) positive animals for Psoroptes equi. There was no statistical correlation between prevalence and host age or sex (c2, p>0,05). P. equi was diagnosed in animals with different hair color. The dorsal region (withers to hip) was the most affected area of the body.

Abstract in English:

Lima E.F., Riet-Correa F., Castro R.S., Gomes A.A.B. & Lima F.S. 2005. [Clinical signs, distribution of the lesions in the central nervous system and epidemiology of rabies in northeastern Brazil.] Sinais clínicos, distribuição das lesões no sistema nervoso e epidemiologia da raiva em herbívoros na região Nordeste do Brasil. Pesquisa Veterinária Brasileira 25(4):250-264. Centro de Saúde e Tecnologia Rural, Campus de Patos, Universidade Federal de Campina Grande, Patos, PB 58700-000, Brazil. E-mail: riet@cstr.ufcg.br Twenty four outbreaks of rabies in cattle, 4 in horses, 2 in sheep, and 2 in goats are reported in northeastern Brazil. All outbreaks occurred in the state of Paraíba, except one in horses that occurred in the state of Rio Grande do Norte. All outbreaks, except one in sheep, were probably transmitted by vampire-bats, but the transmission by foxes (Dusicyon vetulus) is also possible. Clinical signs were characteristic for distribution of the lesions in the central nervous system (CNS). In cattle, signs were mainly of the paralytic form of rabies, caused by lesions on the spinal cord, brain stem and cerebellum; but some animals showed also depression, excitation and other signs due to cerebral lesions. In 3 out of 5 horses, the main clinical signs were due to lesions in the cerebrum, and 2 had the paralytic form. From 4 sheep and 2 goats affected, 4 showed clinical signs of the paralytic form; but in 1 goat and 1 sheep the main clinical signs were caused by cerebral lesions. All affected animals, except 1 goat, had a clinical manifestation period of 2-8 days. The only gross lesions were distention of the urinary bladder in 4 cattle and distention of the rectum in 2 others. Two horses had skin lesions due to traumatic injury. Histologic lesions were diffuse non-suppurative encephalomyelitis and meningitis. In the horses, and in one goat with a clinical manifestation period of 35 days, the lesions were more severe, with neuronal necrosis, neuronophagia, and presence of axonal spheroids. Negri bodies were found in 87% (20/23) of the cattle cases examined histologically. In small ruminants Negri bodies were found in 83% (5/6) of the cases. In sheep, goats and cattle, Negri bodies were more frequent in the cerebellum, but they were found also in brain stem, spinal cord and cerebrum. In horses, Negri bodies were found in small amounts only in the cortex of one animal, and in the cortex and hippocampus of another. Histologic lesions and Negri bodies in the trigeminal ganglia were less frequent than in the CNS. These results show that in rabies of herbivores, clinical signs and distribution of lesions in the CNS are variable, so that for the diagnosis and adequate clinical evaluation and the histologic study of different areas of the CNS are necessary. This also suggests that when the fluorescent antibody test and mouse inoculation test are negative, they should be repeated with samples from different areas of the brain and spinal cord. Frequency data of diseases from 4 diagnostic laboratories were used to estimate cattle deaths due to rabies in 3 Brazilian states. In Paraíba, with a population of 918,262 cattle, the annual death rate is estimated in 8,609 heads. In Mato Grosso do Sul, with a population of 23 millions cattle, deaths caused by rabies are estimated in 149,500 heads, and in Rio Grande do Sul, with a cattle population of 13 millions, cattle deaths due to rabies are estimated in 13,000 to 16,250 heads. If these data are used to estimate cattle losses in Brazil, with a cattle population of 195 millions, it can be estimated that 842,688 deaths are caused annually by rabies.

• Rabies cattle sheep goats horses pathology clinical signs economical impact.

Abstract in Portuguese:

Lima E.F., Riet-Correa F., Castro R.S., Gomes A.A.B. & Lima F.S. 2005. [Clinical signs, distribution of the lesions in the central nervous system and epidemiology of rabies in northeastern Brazil.] Sinais clínicos, distribuição das lesões no sistema nervoso e epidemiologia da raiva em herbívoros na região Nordeste do Brasil. Pesquisa Veterinária Brasileira 25(4):250-264. Centro de Saúde e Tecnologia Rural, Campus de Patos, Universidade Federal de Campina Grande, Patos, PB 58700-000, Brazil. E-mail: riet@cstr.ufcg.br Twenty four outbreaks of rabies in cattle, 4 in horses, 2 in sheep, and 2 in goats are reported in northeastern Brazil. All outbreaks occurred in the state of Paraíba, except one in horses that occurred in the state of Rio Grande do Norte. All outbreaks, except one in sheep, were probably transmitted by vampire-bats, but the transmission by foxes (Dusicyon vetulus) is also possible. Clinical signs were characteristic for distribution of the lesions in the central nervous system (CNS). In cattle, signs were mainly of the paralytic form of rabies, caused by lesions on the spinal cord, brain stem and cerebellum; but some animals showed also depression, excitation and other signs due to cerebral lesions. In 3 out of 5 horses, the main clinical signs were due to lesions in the cerebrum, and 2 had the paralytic form. From 4 sheep and 2 goats affected, 4 showed clinical signs of the paralytic form; but in 1 goat and 1 sheep the main clinical signs were caused by cerebral lesions. All affected animals, except 1 goat, had a clinical manifestation period of 2-8 days. The only gross lesions were distention of the urinary bladder in 4 cattle and distention of the rectum in 2 others. Two horses had skin lesions due to traumatic injury. Histologic lesions were diffuse non-suppurative encephalomyelitis and meningitis. In the horses, and in one goat with a clinical manifestation period of 35 days, the lesions were more severe, with neuronal necrosis, neuronophagia, and presence of axonal spheroids. Negri bodies were found in 87% (20/23) of the cattle cases examined histologically. In small ruminants Negri bodies were found in 83% (5/6) of the cases. In sheep, goats and cattle, Negri bodies were more frequent in the cerebellum, but they were found also in brain stem, spinal cord and cerebrum. In horses, Negri bodies were found in small amounts only in the cortex of one animal, and in the cortex and hippocampus of another. Histologic lesions and Negri bodies in the trigeminal ganglia were less frequent than in the CNS. These results show that in rabies of herbivores, clinical signs and distribution of lesions in the CNS are variable, so that for the diagnosis and adequate clinical evaluation and the histologic study of different areas of the CNS are necessary. This also suggests that when the fluorescent antibody test and mouse inoculation test are negative, they should be repeated with samples from different areas of the brain and spinal cord. Frequency data of diseases from 4 diagnostic laboratories were used to estimate cattle deaths due to rabies in 3 Brazilian states. In Paraíba, with a population of 918,262 cattle, the annual death rate is estimated in 8,609 heads. In Mato Grosso do Sul, with a population of 23 millions cattle, deaths caused by rabies are estimated in 149,500 heads, and in Rio Grande do Sul, with a cattle population of 13 millions, cattle deaths due to rabies are estimated in 13,000 to 16,250 heads. If these data are used to estimate cattle losses in Brazil, with a cattle population of 195 millions, it can be estimated that 842,688 deaths are caused annually by rabies.

Abstract in English:

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.

Abstract in English:

Caron L., Brum M.C.S., Moraes M.P., Golde W.T., Arns C.W. & Grubman M.J. 2005. Granulocyte-macrophage colony-stimulating factor does not increase the potency or efficacy of a foot-and-mouth disease virus subunit vaccine. Pesquisa Veterinária Brasileira 25(3):150-158. USDA, ARS, PIADC-FMD Research Unit, PO.Box 848, Greenport, NY 11944 0848, USA. E-mail: mgrubman@piadc.ars.usda.gov Foot-and-mouth disease (FMD) is one of the most feared diseases of livestock worldwide. Vaccination has been a very effective weapon in controlling the disease, however a number of concerns with the current vaccine including the inability of approved diagnostic tests to reliably distinguish vaccinated from infected animals and the need for high containment facilities for vaccine production, have limited its use during outbreaks in countries previously free of the disease. A number of FMD vaccine candidates have been tested and a replication-defective human adenovirus type 5 (Ad5) vector containing the FMDV capsid (P1-2A) and 3C protease coding regions has been shown to completely protect pigs against challenge with the homologous virus (FMDV A12 and A24). An Ad5-P1-2A+3C vaccine for FMDV O1 Campos (Ad5-O1C), however, only induced a low FMDV-specific neutralizing antibody response in swine potency tests. Granulocyte-macrophage colony-stimulating factor (GM-CSF) has been successfully used to stimulate the immune response in vaccine formulations against a number of diseases, including HIV, hepatitis C and B. To attempt to improve the FMDV-specific immune response induced by Ad5-O1C, we inoculated swine with Ad5-O1C and an Ad5 vector containing the gene for porcine GM-CSF (pGM-CSF). However, in the conditions used in this trial, pGM-CSF did not improve the immune response to Ad5-O1C and adversely affected the level of protection of swine challenged with homologous FMDV.

• Foot-and-mouth disease virus O1 Campos Adenovirus Granulocyte-macrophage colony-stimulating factor.

Abstract in Portuguese:

Caron L., Brum M.C.S., Moraes M.P., Golde W.T., Arns C.W. & Grubman M.J. 2005. Granulocyte-macrophage colony-stimulating factor does not increase the potency or efficacy of a foot-and-mouth disease virus subunit vaccine. Pesquisa Veterinária Brasileira 25(3):150-158. USDA, ARS, PIADC-FMD Research Unit, PO.Box 848, Greenport, NY 11944 0848, USA. E-mail: mgrubman@piadc.ars.usda.gov Foot-and-mouth disease (FMD) is one of the most feared diseases of livestock worldwide. Vaccination has been a very effective weapon in controlling the disease, however a number of concerns with the current vaccine including the inability of approved diagnostic tests to reliably distinguish vaccinated from infected animals and the need for high containment facilities for vaccine production, have limited its use during outbreaks in countries previously free of the disease. A number of FMD vaccine candidates have been tested and a replication-defective human adenovirus type 5 (Ad5) vector containing the FMDV capsid (P1-2A) and 3C protease coding regions has been shown to completely protect pigs against challenge with the homologous virus (FMDV A12 and A24). An Ad5-P1-2A+3C vaccine for FMDV O1 Campos (Ad5-O1C), however, only induced a low FMDV-specific neutralizing antibody response in swine potency tests. Granulocyte-macrophage colony-stimulating factor (GM-CSF) has been successfully used to stimulate the immune response in vaccine formulations against a number of diseases, including HIV, hepatitis C and B. To attempt to improve the FMDV-specific immune response induced by Ad5-O1C, we inoculated swine with Ad5-O1C and an Ad5 vector containing the gene for porcine GM-CSF (pGM-CSF). However, in the conditions used in this trial, pGM-CSF did not improve the immune response to Ad5-O1C and adversely affected the level of protection of swine challenged with homologous FMDV.

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:

Diel D.G., Fonseca E.T., Souza S.F., Mazzanti A., Bauermann F., Weiblen R. & Flores E.F. 2005. [Bovine herpesvirus 5 may use the olfactory and trigeminal pathways to invade the central nervous system of rabbits, depending upon the route of inoculation.] O Herpesvírus bovino tipo 5 (BoHV-5) pode utilizar as rotas olfatória ou trigeminal para invadir o sistema nervoso central de coelhos, dependendo da via de inoculação. Pesquisa Veterinária Brasileira 25(3):164-170. Departamento de Medicina Veterinária Preventiva, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: flores@ccr.ufsm.br Bovine herpesvirus type 5 (BoHV-5) is a major etiological agent of meningoencephalitis in cattle. Following replication in the nasal mucosa, viral invasion of the brain is thought to occur mainly by the olfactory pathway. To address the role of this pathway in the pathogenesis of neurological infection in a laboratory model, 30 days old rabbits had the main olfactory bulbs (MOBs) surgically removed and were subsequently inoculated intranasally (IN) or conjunctivally (IC) with a highly neurovirulent BoHV-5 strain (SV-507). Following IN inoculation, 10 out of 10 (100 %) control rabbits developed neurological disease. The clinical onset ranged from day 5 to 10 post-inoculation (pi, average 7.5 days); nine being euthanized in extremis and one recovering after a mild clinical course. In contrast, only one rabbit (9.1 %) of the group lacking the MOBs (n=11) developed neurological disease (onset at day 17 pi). Dexamethasone administration to the survivors (n=10) at day 50pi was followed by virus shedding in nasal and/or ocular secretions by 8 animals, demonstrating that the virus was able to reach the trigeminal ganglia (TG) during acute infection. These results demonstrate that the olfactory route provides the main, yet not the sole access to the brain of rabbits following IN inoculation. To address the role of a second pathway, groups of control (n=12) or MOB-lacking rabbits (n=12) were inoculated into the conjunctival sac (IC), following which the virus would be expected to use the ophtalmic branch of the trigeminal nerve to reach the brain. Ten control rabbits (83.3 %) developed neurological disease upon IC inoculation (onset 15.3 days [11 to 20]). Previous ablation of the MOBs did not affect the frequency and course of neurological disease: ten out of 12 rabbits (83.3 %) lacking the MOBs developed neurological disease (onset 9 to 15 dpi, average: 12.7 days) upon IC inoculation. These results demonstrate that both IN and IC routes may operate in the transport of BoHV-5 to the brain of experimentally infected rabbits, depending on the route of inoculation. IN inoculation results in a fast and efficient transport by the olfactory pathway, the trigeminal route providing an alternative, much slower and less efficient transport; IC inoculation results in efficient viral transport by the trigeminal route, yet with a delayed kinetics comparing to the transport provided by the olfactory pathway.

• Bovine herpesvirus type 5 BoHV-5 neurological infection rabbits.

Abstract in Portuguese:

Diel D.G., Fonseca E.T., Souza S.F., Mazzanti A., Bauermann F., Weiblen R. & Flores E.F. 2005. [Bovine herpesvirus 5 may use the olfactory and trigeminal pathways to invade the central nervous system of rabbits, depending upon the route of inoculation.] O Herpesvírus bovino tipo 5 (BoHV-5) pode utilizar as rotas olfatória ou trigeminal para invadir o sistema nervoso central de coelhos, dependendo da via de inoculação. Pesquisa Veterinária Brasileira 25(3):164-170. Departamento de Medicina Veterinária Preventiva, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: flores@ccr.ufsm.br Bovine herpesvirus type 5 (BoHV-5) is a major etiological agent of meningoencephalitis in cattle. Following replication in the nasal mucosa, viral invasion of the brain is thought to occur mainly by the olfactory pathway. To address the role of this pathway in the pathogenesis of neurological infection in a laboratory model, 30 days old rabbits had the main olfactory bulbs (MOBs) surgically removed and were subsequently inoculated intranasally (IN) or conjunctivally (IC) with a highly neurovirulent BoHV-5 strain (SV-507). Following IN inoculation, 10 out of 10 (100 %) control rabbits developed neurological disease. The clinical onset ranged from day 5 to 10 post-inoculation (pi, average 7.5 days); nine being euthanized in extremis and one recovering after a mild clinical course. In contrast, only one rabbit (9.1 %) of the group lacking the MOBs (n=11) developed neurological disease (onset at day 17 pi). Dexamethasone administration to the survivors (n=10) at day 50pi was followed by virus shedding in nasal and/or ocular secretions by 8 animals, demonstrating that the virus was able to reach the trigeminal ganglia (TG) during acute infection. These results demonstrate that the olfactory route provides the main, yet not the sole access to the brain of rabbits following IN inoculation. To address the role of a second pathway, groups of control (n=12) or MOB-lacking rabbits (n=12) were inoculated into the conjunctival sac (IC), following which the virus would be expected to use the ophtalmic branch of the trigeminal nerve to reach the brain. Ten control rabbits (83.3 %) developed neurological disease upon IC inoculation (onset 15.3 days [11 to 20]). Previous ablation of the MOBs did not affect the frequency and course of neurological disease: ten out of 12 rabbits (83.3 %) lacking the MOBs developed neurological disease (onset 9 to 15 dpi, average: 12.7 days) upon IC inoculation. These results demonstrate that both IN and IC routes may operate in the transport of BoHV-5 to the brain of experimentally infected rabbits, depending on the route of inoculation. IN inoculation results in a fast and efficient transport by the olfactory pathway, the trigeminal route providing an alternative, much slower and less efficient transport; IC inoculation results in efficient viral transport by the trigeminal route, yet with a delayed kinetics comparing to the transport provided by the olfactory pathway.

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.