PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Martins I.V.F., Verocai G.G., Correia T.R., Melo R.M.P.S., Pereira M.J.S., Scott F.B. & Grisi L. 2009. Survey on control and management practices of equine helminths infection. Pesquisa Veterinária Brasileira 29(3):253-257. Departamento de Medicina Veterinária, Centro de Ciências Agrárias, Universidade Federal do Espírito Santo, Cx. Postal 16, Alegre, ES 29500-000, Brazil. E-mail: isabella@cca.ufes.br Twenty-nine stud farms were selected in the Medium Paraíba region of the Rio de Janeiro state, Brazil. After an interview with the person responsible for the animals, faecal samples were collected from mares and analyzed via the EPG technique, faecal cultures, Sedimentation-centrifugo-flotation, and modified Ueno and Baermann techniques. The prevalence of helminths in the mares and in the stud farms was calculated. The stocking rates of pasture, change of horse bedding, absence of pasture rotation, absence of technology in the property, and less frequent treatment of the animals were associated with a greater prevalence of helminths, showing that these variables must be considered in equine control programs. The intensity of the parasitism was also associated with the stocking rate of pasture, absence of dunghill, presence of the animals only in paddocks, lack of technology in the property, less frequent treatment of the animals, and absence of the use of rotation regarding the anthelmintic class.

• Control practices management helminths treatment horses

Abstract in Portuguese:

ABSTRACT.- Martins I.V.F., Verocai G.G., Correia T.R., Melo R.M.P.S., Pereira M.J.S., Scott F.B. & Grisi L. 2009. Survey on control and management practices of equine helminths infection. Pesquisa Veterinária Brasileira 29(3):253-257. Departamento de Medicina Veterinária, Centro de Ciências Agrárias, Universidade Federal do Espírito Santo, Cx. Postal 16, Alegre, ES 29500-000, Brazil. E-mail: isabella@cca.ufes.br Twenty-nine stud farms were selected in the Medium Paraíba region of the Rio de Janeiro state, Brazil. After an interview with the person responsible for the animals, faecal samples were collected from mares and analyzed via the EPG technique, faecal cultures, Sedimentation-centrifugo-flotation, and modified Ueno and Baermann techniques. The prevalence of helminths in the mares and in the stud farms was calculated. The stocking rates of pasture, change of horse bedding, absence of pasture rotation, absence of technology in the property, and less frequent treatment of the animals were associated with a greater prevalence of helminths, showing that these variables must be considered in equine control programs. The intensity of the parasitism was also associated with the stocking rate of pasture, absence of dunghill, presence of the animals only in paddocks, lack of technology in the property, less frequent treatment of the animals, and absence of the use of rotation regarding the anthelmintic class.

Abstract in English:

ABSTRACT.- Cunha N.C., Fonseca A.H., Rezende J., Rozental T., Favacho A.R.M., Barreira J.D., Massard C.L., Lemos E.R.S. 2009. First identification of natural infection of Rickettsia rickettsii in the Rhipicephalus sanguineus tick, in the State of Rio de Janeiro. Pesquisa Veterinária Brasileira 29(2):105-108. Curso de Pós-Graduação em Ciências Veterinárias, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: adivaldo@ufrrj.br The Brazilian Spotted Fever (BSF) is a zoonotic disease caused by Rickettsia rickettsii and transmitted by ticks of the genus Amblyomma, more frequently, Amblyomma cajennense. The aim of this paper was to report the first molecular detection of R. rickettsii on R. sanguineus naturally infected in Rio de Janeiro, Brazil. Ticks were collected from dogs in a rural region of Resende municipality, Rio de Janeiro State, Brazil (22o 30min 9.46sec S, 44o 42min 44.29sec WO), where occurred five human cases of BSF in 2006. The ticks were identified under a stereoscopic microscope and separated in pools by stages, species and sex. DNA extraction was carried out using QIAamp DNA Mini Kit (QIAGEN®). The DNA was submitted to PCR amplification using 04 set of primers: Rr190.70p/Rr190.602n (OmpA, 532bp), BG1-21/BG2-20 (OmpB, 650bp), Tz15/Tz16 (17 kDa protein-encoding gene, 246bp) and RpCS.877p/RpCS.1258n (gltA, 381bp). PCR products were separated by electrophoresis on 1% agarose gels and visualized under ultraviolet light with ethidium bromide. PCR products of the expected sizes were purified by QIAquick® and sequenced by ABI PRISM®. The generated nucleotide sequences were edited with using Bioedit® software and compared with the corresponding homologous sequences available through GenBank, using Discontiguous Mega Blast (http://www.ncbi.nlm.nih.gov). It was confirmed R. rickettsii by sequencing of the material (GenBank FJ356230). The molecular characterization of R. rickettsii in the tick R. sanguineus emphasizes the role of dogs as carriers of ticks from the environment to home. Moreover, this result suggests that there is a considerable chance for active participation of R. sanguineus as one of tick species in the transmission of R. ricketsii to human being in the Brazilian territory.

• Rhipicephalus sanguineus Acari Ixodidae Rickettsia rickettsii molecular analysis Brazilian spotted fever

Abstract in Portuguese:

ABSTRACT.- Cunha N.C., Fonseca A.H., Rezende J., Rozental T., Favacho A.R.M., Barreira J.D., Massard C.L., Lemos E.R.S. 2009. First identification of natural infection of Rickettsia rickettsii in the Rhipicephalus sanguineus tick, in the State of Rio de Janeiro. Pesquisa Veterinária Brasileira 29(2):105-108. Curso de Pós-Graduação em Ciências Veterinárias, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: adivaldo@ufrrj.br The Brazilian Spotted Fever (BSF) is a zoonotic disease caused by Rickettsia rickettsii and transmitted by ticks of the genus Amblyomma, more frequently, Amblyomma cajennense. The aim of this paper was to report the first molecular detection of R. rickettsii on R. sanguineus naturally infected in Rio de Janeiro, Brazil. Ticks were collected from dogs in a rural region of Resende municipality, Rio de Janeiro State, Brazil (22o 30min 9.46sec S, 44o 42min 44.29sec WO), where occurred five human cases of BSF in 2006. The ticks were identified under a stereoscopic microscope and separated in pools by stages, species and sex. DNA extraction was carried out using QIAamp DNA Mini Kit (QIAGEN®). The DNA was submitted to PCR amplification using 04 set of primers: Rr190.70p/Rr190.602n (OmpA, 532bp), BG1-21/BG2-20 (OmpB, 650bp), Tz15/Tz16 (17 kDa protein-encoding gene, 246bp) and RpCS.877p/RpCS.1258n (gltA, 381bp). PCR products were separated by electrophoresis on 1% agarose gels and visualized under ultraviolet light with ethidium bromide. PCR products of the expected sizes were purified by QIAquick® and sequenced by ABI PRISM®. The generated nucleotide sequences were edited with using Bioedit® software and compared with the corresponding homologous sequences available through GenBank, using Discontiguous Mega Blast (http://www.ncbi.nlm.nih.gov). It was confirmed R. rickettsii by sequencing of the material (GenBank FJ356230). The molecular characterization of R. rickettsii in the tick R. sanguineus emphasizes the role of dogs as carriers of ticks from the environment to home. Moreover, this result suggests that there is a considerable chance for active participation of R. sanguineus as one of tick species in the transmission of R. ricketsii to human being in the Brazilian territory.

Abstract in English:

ABSTRACT.- Diéguez F.J., Yus E., Sanjuán M.L., Vilar M.J. & Arnaiz I. 2008. Monitoring bovine viral diarrhea virus (BVDV) infection status in dairy herds. Pesquisa Veterinária Brasileira 28(12):588-592. Unidad de Epidemiología y Sanidad Animal, Instituto de Investigación y Análisis Alimentarios, Facultad de Veterinaria s/n, Lugo 27002, Spain. E-mail: franciscojavier.dieguez@usc.es This study was designed to assess the relationship between antibodies against bovine viral diarrhea virus (BVDV) determined in the bulk tank milk (BTM) and the within-herd seroprevalence. We also assessed the efficiency of measuring antibody levels in BTM samples to monitor BVDV infection status in a herd. In the 81 farms included in the study, BTM samples were obtained and blood samples withdrawn from all cattle older than one year. The infection status was then determined in serum and milk using a commercial blocking ELISA based on the detection of anti-p80 antibodies. Apart from these baseline serum and milk samples, another BTM sample was collected from each herd 9 months later, and a third BTM sample obtained 9 months after this. In these second and third milk samples, anti-BVDV antibodies were determined using the same ELISA kit. Statistical tests revealed good agreement between herd seroprevalences (% seropositive animals in the herd) and the antibody levels detected in the BTM samples. During the 18 months of follow-up, the farms with persistently infected cattle at the study outset (14.8% of the herds) showed a significant decrease in BTM antibody titers after virus clearance. Conversely, a significant increase in BTM antibody levels was observed in the herds infected with BVDV during the follow-up period. Our findings indicate that monitoring antibody levels in the BTM is a useful method of identifying changes in the BVDV infection status of a herd.

• Bovine viral diarrhea vírus BVDV antibodies diagnostic milk

Abstract in Portuguese:

ABSTRACT.- Diéguez F.J., Yus E., Sanjuán M.L., Vilar M.J. & Arnaiz I. 2008. Monitoring bovine viral diarrhea virus (BVDV) infection status in dairy herds. Pesquisa Veterinária Brasileira 28(12):588-592. Unidad de Epidemiología y Sanidad Animal, Instituto de Investigación y Análisis Alimentarios, Facultad de Veterinaria s/n, Lugo 27002, Spain. E-mail: franciscojavier.dieguez@usc.es This study was designed to assess the relationship between antibodies against bovine viral diarrhea virus (BVDV) determined in the bulk tank milk (BTM) and the within-herd seroprevalence. We also assessed the efficiency of measuring antibody levels in BTM samples to monitor BVDV infection status in a herd. In the 81 farms included in the study, BTM samples were obtained and blood samples withdrawn from all cattle older than one year. The infection status was then determined in serum and milk using a commercial blocking ELISA based on the detection of anti-p80 antibodies. Apart from these baseline serum and milk samples, another BTM sample was collected from each herd 9 months later, and a third BTM sample obtained 9 months after this. In these second and third milk samples, anti-BVDV antibodies were determined using the same ELISA kit. Statistical tests revealed good agreement between herd seroprevalences (% seropositive animals in the herd) and the antibody levels detected in the BTM samples. During the 18 months of follow-up, the farms with persistently infected cattle at the study outset (14.8% of the herds) showed a significant decrease in BTM antibody titers after virus clearance. Conversely, a significant increase in BTM antibody levels was observed in the herds infected with BVDV during the follow-up period. Our findings indicate that monitoring antibody levels in the BTM is a useful method of identifying changes in the BVDV infection status of a herd.

Abstract in English:

ABSTRACT.- Koller F.L., Borowski S.M., Asanome W., Hein G., Lagemann F.L., Driemeier D. & Barcellos D.E.S.N. 2008. [Dental periapical abscesses in piglets affected by postweaning multisystemic wasting syndrome PMWS.] Abscessos dentários periapi-cais em leitões com síndrome multissistêmica do definhamento. Pesquisa Veterinária Brasi-leira 28(6):271-274. Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br Swine producers have historically resected needle teeth of newborn pigs to prevent potential injuries to the sow mammary gland and faces of littermates. However, the possible impact of this practice on pig performance has been questioned. As part of a study, 280 PMWS affected piglets, with 40-70 days of age, were examined for the presence of dental lesions immediately after euthanasia. Most pigs were confirmed as PMWS by the detection of typical microscopic lesions and immunohistochemical pattern. At least one periapical abscess was observed in 58 piglets (20.7%), of which 12 had multiple abscesses. There were 22 (31.4%), 16 (22.9%), 4 (5.7%), 23 (32.9%), and 5 (7.1%) abscesses in 3rd upper incisives, 3rd lower incisives, upper canines, lower canines, and other teeth, respectively. The higher prevalence of dental abscesses observed in 3rd incisives and lower canines is probably associated with the wider area of grinding or clipping to which these teeth were subjected. Among bacteria isolated from samples collected from 65 abscesses, Streptococcus sp. was the most prevalent bacteria and was present in 21.48% and 27.7% of the aerobic and anaerobic isolates, respectively. In the second most frequent group were coryneform microorganisms, which showed higher rate of isolation under anaerobic atmosphere than in aerobic culture. There was preponderance of Gram-positive isolates. It could not be determined whether these bacterial co-infections predisposed pigs to development of PMWS-type lesions or if were subsequent to the PCV2 infection.

• Periapical abscess causal bacteria co-infection PMWS piglet teeth resection teeth clipping

Abstract in Portuguese:

ABSTRACT.- Koller F.L., Borowski S.M., Asanome W., Hein G., Lagemann F.L., Driemeier D. & Barcellos D.E.S.N. 2008. [Dental periapical abscesses in piglets affected by postweaning multisystemic wasting syndrome PMWS.] Abscessos dentários periapi-cais em leitões com síndrome multissistêmica do definhamento. Pesquisa Veterinária Brasi-leira 28(6):271-274. Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br Swine producers have historically resected needle teeth of newborn pigs to prevent potential injuries to the sow mammary gland and faces of littermates. However, the possible impact of this practice on pig performance has been questioned. As part of a study, 280 PMWS affected piglets, with 40-70 days of age, were examined for the presence of dental lesions immediately after euthanasia. Most pigs were confirmed as PMWS by the detection of typical microscopic lesions and immunohistochemical pattern. At least one periapical abscess was observed in 58 piglets (20.7%), of which 12 had multiple abscesses. There were 22 (31.4%), 16 (22.9%), 4 (5.7%), 23 (32.9%), and 5 (7.1%) abscesses in 3rd upper incisives, 3rd lower incisives, upper canines, lower canines, and other teeth, respectively. The higher prevalence of dental abscesses observed in 3rd incisives and lower canines is probably associated with the wider area of grinding or clipping to which these teeth were subjected. Among bacteria isolated from samples collected from 65 abscesses, Streptococcus sp. was the most prevalent bacteria and was present in 21.48% and 27.7% of the aerobic and anaerobic isolates, respectively. In the second most frequent group were coryneform microorganisms, which showed higher rate of isolation under anaerobic atmosphere than in aerobic culture. There was preponderance of Gram-positive isolates. It could not be determined whether these bacterial co-infections predisposed pigs to development of PMWS-type lesions or if were subsequent to the PCV2 infection.

Abstract in English:

Abstract.- Zlotowski P., Corrêa A.M.R., Barcellos D.E.S., Cruz C.E.F., Asanome W., Barry A.F., Alfieri A.A. & Driemeier D. 2008. Intestinal lesions in pigs affected with postweaning multisystemic wasting syndrome. Pesquisa Veterinária Brasileira 28(6):313-318. Departamento de Patologia Clinica Veterinária, Faculdade de Medicina Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br Samples of mesenteric lymph nodes and intestines from 79 unthrifty 3- to 5-month-old postweaning pigs, confirmed as naturally affected with postweaning multisystemic wasting syndrome (PMWS), were studied. Pigs originated from 12 farms in southern Brazil and were selected on the basis of clinical signs and/or gross lesions suggestive of enteric disorder. Lymphohistiocytic infiltrates of varying intensity were associated with anti-porcine circovirus type 2 (anti-PCV2) immunostaining (IS) in samples of intestines and mesenteric lymph nodes from all pigs. Although most findings were similar to those described in PCV2-associated enteritis, anti-PCV2 IS in association with depletion of the goblet cell mucin stores (24 pigs), diffuse ileal villous atrophy and fusion (18 pigs), and dilatation of the lymphatic vessels (11 pigs) combined or not with lymphangitis were also observed. PCV2 antigen was immunohistochemically demonstrated in the cytoplasm and nuclei from intralesional epithelial cells, histiocytes, and endothelial-like cells in intestinal tissues. Together these findings imply an association with PCV2. The presence of co-infections by Lawsonia intracellularis, Brachyspira spp., Mycobacterium spp., Salmonella spp., rotavirus, parvovirus, coronavirus and enteric calicivirus with PCV2 in the intestinal lesions was investigated.

• Circovirus co-infections enteric lesions PCV2 PMWS

Abstract in Portuguese:

Abstract.- Zlotowski P., Corrêa A.M.R., Barcellos D.E.S., Cruz C.E.F., Asanome W., Barry A.F., Alfieri A.A. & Driemeier D. 2008. Intestinal lesions in pigs affected with postweaning multisystemic wasting syndrome. Pesquisa Veterinária Brasileira 28(6):313-318. Departamento de Patologia Clinica Veterinária, Faculdade de Medicina Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br Samples of mesenteric lymph nodes and intestines from 79 unthrifty 3- to 5-month-old postweaning pigs, confirmed as naturally affected with postweaning multisystemic wasting syndrome (PMWS), were studied. Pigs originated from 12 farms in southern Brazil and were selected on the basis of clinical signs and/or gross lesions suggestive of enteric disorder. Lymphohistiocytic infiltrates of varying intensity were associated with anti-porcine circovirus type 2 (anti-PCV2) immunostaining (IS) in samples of intestines and mesenteric lymph nodes from all pigs. Although most findings were similar to those described in PCV2-associated enteritis, anti-PCV2 IS in association with depletion of the goblet cell mucin stores (24 pigs), diffuse ileal villous atrophy and fusion (18 pigs), and dilatation of the lymphatic vessels (11 pigs) combined or not with lymphangitis were also observed. PCV2 antigen was immunohistochemically demonstrated in the cytoplasm and nuclei from intralesional epithelial cells, histiocytes, and endothelial-like cells in intestinal tissues. Together these findings imply an association with PCV2. The presence of co-infections by Lawsonia intracellularis, Brachyspira spp., Mycobacterium spp., Salmonella spp., rotavirus, parvovirus, coronavirus and enteric calicivirus with PCV2 in the intestinal lesions was investigated.

Abstract in English:

ABSTRACT.- Nóbrega Jr J.E., Macêdo J.T.S.A., Araújo J.A.S., Dantas A.F.M., Soares M.P. & Riet-Correa F. 2008. [Contagious echtyma in sheep and goats in the semiarid of Paraíba, Brazil.] Ectima contagioso em ovinos e caprinos no semi-árido da Paraíba. Pesquisa Veterinária Brasileira 28(3):135-139. Hospital Veterinário, Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-970 Patos, PB, Brazil. E-mail: franklin.riet@pq.cnpq.br Ten outbreaks of contagious ecthyma in goats and two in sheep in the semiarid of Paraíba State are reported. Young animals were more frequently affected, but in 8 outbreaks adult animals were also affected, mainly lactating goats which developed udder lesions. None of the affected flocks had been vaccinated. Upon histologic examination the epidermis showed acanthosis with pseudoepitheliomatous hyperplasia and multifocal ballooning degeneration forming vesicles or pustules. Eosinophilic inclusion bodies were observed in keratinocytes. Crust of necrotic cells, hyperkeratosis, and intracorneal microabscesses or large ulcerated areas were also observed. Severe diffuse infiltration by mononuclear cells was observed in the dermis. A human case was observed in an investigator that was feeding a goat that later appeared with lesions of the disease. In this case, the virus was identified by electron microscopy of a skin biopsy. These results show that contagious ecthyma is endemic in Northeastern Brazil and therefore systematic vaccination of the flocks is necessary to control the disease. The use of gloves to handle affected animals is advisable to minimize the risk of human exposure.

• Contagious ecthyma sheep goat human infection parapoxvirus Poxviridae

Abstract in Portuguese:

ABSTRACT.- Nóbrega Jr J.E., Macêdo J.T.S.A., Araújo J.A.S., Dantas A.F.M., Soares M.P. & Riet-Correa F. 2008. [Contagious echtyma in sheep and goats in the semiarid of Paraíba, Brazil.] Ectima contagioso em ovinos e caprinos no semi-árido da Paraíba. Pesquisa Veterinária Brasileira 28(3):135-139. Hospital Veterinário, Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-970 Patos, PB, Brazil. E-mail: franklin.riet@pq.cnpq.br Ten outbreaks of contagious ecthyma in goats and two in sheep in the semiarid of Paraíba State are reported. Young animals were more frequently affected, but in 8 outbreaks adult animals were also affected, mainly lactating goats which developed udder lesions. None of the affected flocks had been vaccinated. Upon histologic examination the epidermis showed acanthosis with pseudoepitheliomatous hyperplasia and multifocal ballooning degeneration forming vesicles or pustules. Eosinophilic inclusion bodies were observed in keratinocytes. Crust of necrotic cells, hyperkeratosis, and intracorneal microabscesses or large ulcerated areas were also observed. Severe diffuse infiltration by mononuclear cells was observed in the dermis. A human case was observed in an investigator that was feeding a goat that later appeared with lesions of the disease. In this case, the virus was identified by electron microscopy of a skin biopsy. These results show that contagious ecthyma is endemic in Northeastern Brazil and therefore systematic vaccination of the flocks is necessary to control the disease. The use of gloves to handle affected animals is advisable to minimize the risk of human exposure.

Abstract in English:

ABSTRACT.- Henzel A., Diel D.G., Arenhart S., Vogel F.S.F., Weiblen R. & Flores E.F. 2008. [Virological and clinico-pathological features of acute vulvovaginitis and latent infection by bovine herpesvirus 1.2 in heifers experimentally infected.] Aspectos virológicos e clínico-patológicos da infecção genital aguda e latente pelo herpesvírus bovino tipo 1.2 em bezerras experimentalmente infectadas. Pesquisa Veterinária Brasileira 28(3):140-148. Departamento de Medicina Veterinária Preventiva, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: flores@ccr.ufsm.br Venereal infection of heifers and cows with bovine herpesvirus type 1.2 (BoHV-1.2) may result in vulvovaginitis and transient infertility. The acute infection is followed by the establishment of latent infection which can be periodically reactivated. We herein describe the virology and clinico-pathological aspects of acute and recrudescent vulvovaginitis in heifers inoculated with a Brazilian BoHV-1.2 isolate recovered from an outbreak of balanoposthitis. Genital inoculation of isolate SV-56/90 (108.1TCID50/animal) in four eight-months-old heifers resulted in efficient virus replication in the genital mucosa and the development of moderate to severe vulvovaginitis. The inoculated heifers shed virus in genital secretions in titers up to 107.3TCID50/mL until day 10 pi and developed genital congestion, swelling, vesicles and pustules. The vesicles and pustules increased in size eventually coalesced and became covered with a yellowish exsudate. These signs appeared at day 2 pi, increased in severity up to days 5 - 8 pi and progressively subsided thereafter. Dexamethasone administration at day 55 pi resulted in virus shedding in vaginal secretions for up to 10 days. Virus reactivation in all animals was accompanied by clinical recrudescence of the disease, yet less severe than during acute infection. Examination of sacral ganglia and lymph nodes by PCR at day 36 post-reactivation revealed the presence of latent viral DNA in the pudendal (4/4), genito-femoral, sciatic and rectal caudal (3/4) and obturator nerve ganglia (1/4); in addition to several regional lymph nodes. These results demonstrate the virulence of isolate SV-56/90 for heifers and pave the way for its use in further pathogenesis studies and vaccine-challenge trials.

• Bovine herpesvirus BoHV-1.2 vulvovaginitis genital infection latency reactivation

Abstract in Portuguese:

ABSTRACT.- Henzel A., Diel D.G., Arenhart S., Vogel F.S.F., Weiblen R. & Flores E.F. 2008. [Virological and clinico-pathological features of acute vulvovaginitis and latent infection by bovine herpesvirus 1.2 in heifers experimentally infected.] Aspectos virológicos e clínico-patológicos da infecção genital aguda e latente pelo herpesvírus bovino tipo 1.2 em bezerras experimentalmente infectadas. Pesquisa Veterinária Brasileira 28(3):140-148. Departamento de Medicina Veterinária Preventiva, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: flores@ccr.ufsm.br Venereal infection of heifers and cows with bovine herpesvirus type 1.2 (BoHV-1.2) may result in vulvovaginitis and transient infertility. The acute infection is followed by the establishment of latent infection which can be periodically reactivated. We herein describe the virology and clinico-pathological aspects of acute and recrudescent vulvovaginitis in heifers inoculated with a Brazilian BoHV-1.2 isolate recovered from an outbreak of balanoposthitis. Genital inoculation of isolate SV-56/90 (108.1TCID50/animal) in four eight-months-old heifers resulted in efficient virus replication in the genital mucosa and the development of moderate to severe vulvovaginitis. The inoculated heifers shed virus in genital secretions in titers up to 107.3TCID50/mL until day 10 pi and developed genital congestion, swelling, vesicles and pustules. The vesicles and pustules increased in size eventually coalesced and became covered with a yellowish exsudate. These signs appeared at day 2 pi, increased in severity up to days 5 - 8 pi and progressively subsided thereafter. Dexamethasone administration at day 55 pi resulted in virus shedding in vaginal secretions for up to 10 days. Virus reactivation in all animals was accompanied by clinical recrudescence of the disease, yet less severe than during acute infection. Examination of sacral ganglia and lymph nodes by PCR at day 36 post-reactivation revealed the presence of latent viral DNA in the pudendal (4/4), genito-femoral, sciatic and rectal caudal (3/4) and obturator nerve ganglia (1/4); in addition to several regional lymph nodes. These results demonstrate the virulence of isolate SV-56/90 for heifers and pave the way for its use in further pathogenesis studies and vaccine-challenge trials.

Abstract in English:

ABSTRACT.- Martins C.F., Madruga C.R., Koller W.W., Araújo F.R., Soares C.O., Kessler R.H., Melo E.S.P., Rios L.R., Almeida R.C.F., Lima Jr M.S.C., Barros A.T.M. & Marques L.C. 2008. Trypanosoma vivax infection dynamics in a cattle herd maintained in a transition area between Pantanal lowlands and highlands of Mato Grosso do Sul, Brazil. Pesquisa Veterinária Brasileira 28(1):51-56. Departamento de Clínica Médica da Universidade para o Desenvolvimento do Estado e da Região do Pantanal, Rua Ceará 333, Bairro Miguel Couto, Cx. Postal 2153, Campo Grande, MS 79003-010, Brazil. E-mail: claudio.madruga@pq.cnpq.br Trypanosoma vivax outbreaks in beef cattle in the Pantanal region of Mato Grosso do Sul state, Brazil, causes relevant economical impact due to weight loss, abortion and mortality. Cattle moved from the Pantanal to adjacent areas of this ecosystem for breeding and fattening is a common feature. Therefore an epidemiological study on breeding cows in the transition area between Pantanal lowland and adjacent highlands of Mato Grosso do Sul was performed to determine the T. vivax infection dynamics and outbreak risk. Three experimental groups were formed: Group 1 consisted of cows parasitologically negative by the Woo test and in the enzyme-linked immunosorbent assay for T. vivax antibody detection (Tv-ELISA-Ab); Group 2 parasitologically negative and positive in the Tv-ELISA-Ab; and in Group 3 cows were parasitologically positive and with positive reactions in the Tv-ELISA-Ab. During 24 months, the cows’ dislodgment between the above established groups was monitored by Woo test and Tv-ELISA-Ab exams. The tabanid population was also monitored and the highest number occurred during the rainy season. Although parasitemias were detected only in the first four samplings of the experimental period, the cows could be considered as trypanotolerant, because no clinical signs were observed. Despite the higher T. vivax incidence during the dry season, no disease symptoms were seen. Even though T. vivax epidemiological situation in the herd was characterized as endemic with seasonal variation, the probability of outbreaks was null within the conditions of the study.

• Trypanosoma (Dutonella) vivax cattle tabanids infection dynamics epidemiology

Abstract in Portuguese:

ABSTRACT.- Martins C.F., Madruga C.R., Koller W.W., Araújo F.R., Soares C.O., Kessler R.H., Melo E.S.P., Rios L.R., Almeida R.C.F., Lima Jr M.S.C., Barros A.T.M. & Marques L.C. 2008. Trypanosoma vivax infection dynamics in a cattle herd maintained in a transition area between Pantanal lowlands and highlands of Mato Grosso do Sul, Brazil. Pesquisa Veterinária Brasileira 28(1):51-56. Departamento de Clínica Médica da Universidade para o Desenvolvimento do Estado e da Região do Pantanal, Rua Ceará 333, Bairro Miguel Couto, Cx. Postal 2153, Campo Grande, MS 79003-010, Brazil. E-mail: claudio.madruga@pq.cnpq.br Trypanosoma vivax outbreaks in beef cattle in the Pantanal region of Mato Grosso do Sul state, Brazil, causes relevant economical impact due to weight loss, abortion and mortality. Cattle moved from the Pantanal to adjacent areas of this ecosystem for breeding and fattening is a common feature. Therefore an epidemiological study on breeding cows in the transition area between Pantanal lowland and adjacent highlands of Mato Grosso do Sul was performed to determine the T. vivax infection dynamics and outbreak risk. Three experimental groups were formed: Group 1 consisted of cows parasitologically negative by the Woo test and in the enzyme-linked immunosorbent assay for T. vivax antibody detection (Tv-ELISA-Ab); Group 2 parasitologically negative and positive in the Tv-ELISA-Ab; and in Group 3 cows were parasitologically positive and with positive reactions in the Tv-ELISA-Ab. During 24 months, the cows’ dislodgment between the above established groups was monitored by Woo test and Tv-ELISA-Ab exams. The tabanid population was also monitored and the highest number occurred during the rainy season. Although parasitemias were detected only in the first four samplings of the experimental period, the cows could be considered as trypanotolerant, because no clinical signs were observed. Despite the higher T. vivax incidence during the dry season, no disease symptoms were seen. Even though T. vivax epidemiological situation in the herd was characterized as endemic with seasonal variation, the probability of outbreaks was null within the conditions of the study.

Abstract in English:

ABSTRACT.- Almeida S.R., Diel D.G., Rissi D.R., Weiblen R. & Flores E.F. 2008. [Clinic and pathological characterization of acute mammillitis in lactating ewes inoculated with bovine herpesvirus 2.] Caracterização clinicopatológica da mamilite aguda em ovelhas lactantes inoculadas experimentalmente com o herpesvírus bovino 2. Pesquisa Veterinária Brasileira 28(1):87-94. Departamento de Medicina Veterinária Preventiva, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil. E-mail: flores@ccr.ufsm.br Mammillitis caused by bovine herpesvirus type 2 (BoHV-2) is an important disease in dairy herds yet its pathogenesis remains largely unknown. This report describes the reproduction and characterization of acute mammillitis in lactating ewes inoculated with BoHV-2 in the skin of the udder and teats. Five out of eight inoculated ewes developed large plaques, with focal necrosis, small vesicles and crust formation in the inoculated areas. The lesions were first observed on day 4 post-inoculation (pi), progressed in size and severity up to days 7-8pi and subsided progressively thereafter. Infectious virus was isolated from the lesions at days 7 and 8pi. Viral antigens and herpesvirus-like particles were demonstrated by electron microscopy in lesions examined at days 5, 6 and 10pi. Histological findings included epithelial necrosis, erosions and ulcers, and formation of syncytial cells. Intranuclear inclusions bodies in epithelial, syncytial and inflammatory cells and lymphoplasmacytic inflammatory infiltrate in the dermis were also observed. In a second experiment, seven out of ten lambs inoculated into the nostrils and muzzle developed nasal hyperemia and discharge, vesicles, and erosions in the nose. Infectious virus was isolated from lesions during up to three days and all lambs seroconverted to BoHV-2. Attempts to reactivate the latent infection by dexamethasone administration on day 40pi failed, since virus shedding, clinical recrudescence or seroconversion were not observed. The reproduction of acute infection and mammillitis resembling that occurring in cattle paves the way for the use of sheep to study several aspects of the biology of BoHV-2 infection.

• Bovine herpesvirus-2 BoHV-2 mammillitis sheep experimental infection

Abstract in Portuguese:

ABSTRACT.- Almeida S.R., Diel D.G., Rissi D.R., Weiblen R. & Flores E.F. 2008. [Clinic and pathological characterization of acute mammillitis in lactating ewes inoculated with bovine herpesvirus 2.] Caracterização clinicopatológica da mamilite aguda em ovelhas lactantes inoculadas experimentalmente com o herpesvírus bovino 2. Pesquisa Veterinária Brasileira 28(1):87-94. Departamento de Medicina Veterinária Preventiva, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil. E-mail: flores@ccr.ufsm.br Mammillitis caused by bovine herpesvirus type 2 (BoHV-2) is an important disease in dairy herds yet its pathogenesis remains largely unknown. This report describes the reproduction and characterization of acute mammillitis in lactating ewes inoculated with BoHV-2 in the skin of the udder and teats. Five out of eight inoculated ewes developed large plaques, with focal necrosis, small vesicles and crust formation in the inoculated areas. The lesions were first observed on day 4 post-inoculation (pi), progressed in size and severity up to days 7-8pi and subsided progressively thereafter. Infectious virus was isolated from the lesions at days 7 and 8pi. Viral antigens and herpesvirus-like particles were demonstrated by electron microscopy in lesions examined at days 5, 6 and 10pi. Histological findings included epithelial necrosis, erosions and ulcers, and formation of syncytial cells. Intranuclear inclusions bodies in epithelial, syncytial and inflammatory cells and lymphoplasmacytic inflammatory infiltrate in the dermis were also observed. In a second experiment, seven out of ten lambs inoculated into the nostrils and muzzle developed nasal hyperemia and discharge, vesicles, and erosions in the nose. Infectious virus was isolated from lesions during up to three days and all lambs seroconverted to BoHV-2. Attempts to reactivate the latent infection by dexamethasone administration on day 40pi failed, since virus shedding, clinical recrudescence or seroconversion were not observed. The reproduction of acute infection and mammillitis resembling that occurring in cattle paves the way for the use of sheep to study several aspects of the biology of BoHV-2 infection.

Abstract in English:

Abstract.- Pescador C.A., Bandarra P.M., Castro L.A., Antoniassi N.A.B., Ravazollo, A.P., Sonne L. Cruz C.E.F. & Driemeier D. 2007. Co-infection by porcine circovirus type 2 and porcine parvovirus in aborted fetuses and stillborn piglets in southern Brazil. Pesquisa Veterinária Brasileira 27(10):425-429. Departamento de Patologia Clínica Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br Porcine circovirus types 1 and 2 (PCV1, PCV2) and porcine parvovirus (PPV) are widespread in pig populations around the world. Nevertheless, only PCV2 has been associated with different clinical syndromes, thus representing a major problem to the pig industry. The association of cases of swine abortions and stillborns with PCV1 and PCV2 and PPV was studied retrospectively (2005-2007). Additional pathogens were also investigated in lesioned fetuses. The studied litters included stillborn piglets and several mummified fetuses of varied sizes. Ventricular dilatation, myocardial pale areas, and mesocolic edema were the gross lesions. Escherichia coli was detected as co-infecting with PCV2 the cases in which mesocolic edema was seen. Microscopic lesions included non-suppurative myocarditis, myocardial necrosis and fibrosis, mineralization foci and intranuclear inclusion bodies in cardiomyocytes, and interstitial mononuclear pneumonia. Samples from 7 (5.78 per cent) of 121 aborted fetuses and stillborn piglets had lesions consistent with a viral cause and showed both positive anti-PCV2 immunostaining as well as PCV2-PCR. In samples from 3 (2.47 per cent) of these 7 fetuses, co-infection with PPV was confirmed by Nested-PCR. Both viruses were detected in fetuses at different stages of gestation. Viral antigens of PCV2 were detected by immunohistochemistry mainly in macrophages and myocytes. PCV1 individually was not detected in any of these affected fetuses, but it was associated with PCV2 and/or PPV in some of them. These findings indicate that PCV2 alone or in association with PPV should be kept in mind when investigating causes of infectious abortion in pigs in Brazil.

• Abortion PCV2 PCV1 PPV stillborn swine Brazil

Abstract in Portuguese:

Abstract.- Pescador C.A., Bandarra P.M., Castro L.A., Antoniassi N.A.B., Ravazollo, A.P., Sonne L. Cruz C.E.F. & Driemeier D. 2007. Co-infection by porcine circovirus type 2 and porcine parvovirus in aborted fetuses and stillborn piglets in southern Brazil. Pesquisa Veterinária Brasileira 27(10):425-429. Departamento de Patologia Clínica Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Porto Alegre, RS 91540-000, Brazil. E-mail: davetpat@ufrgs.br Porcine circovirus types 1 and 2 (PCV1, PCV2) and porcine parvovirus (PPV) are widespread in pig populations around the world. Nevertheless, only PCV2 has been associated with different clinical syndromes, thus representing a major problem to the pig industry. The association of cases of swine abortions and stillborns with PCV1 and PCV2 and PPV was studied retrospectively (2005-2007). Additional pathogens were also investigated in lesioned fetuses. The studied litters included stillborn piglets and several mummified fetuses of varied sizes. Ventricular dilatation, myocardial pale areas, and mesocolic edema were the gross lesions. Escherichia coli was detected as co-infecting with PCV2 the cases in which mesocolic edema was seen. Microscopic lesions included non-suppurative myocarditis, myocardial necrosis and fibrosis, mineralization foci and intranuclear inclusion bodies in cardiomyocytes, and interstitial mononuclear pneumonia. Samples from 7 (5.78 per cent) of 121 aborted fetuses and stillborn piglets had lesions consistent with a viral cause and showed both positive anti-PCV2 immunostaining as well as PCV2-PCR. In samples from 3 (2.47 per cent) of these 7 fetuses, co-infection with PPV was confirmed by Nested-PCR. Both viruses were detected in fetuses at different stages of gestation. Viral antigens of PCV2 were detected by immunohistochemistry mainly in macrophages and myocytes. PCV1 individually was not detected in any of these affected fetuses, but it was associated with PCV2 and/or PPV in some of them. These findings indicate that PCV2 alone or in association with PPV should be kept in mind when investigating causes of infectious abortion in pigs in Brazil.