PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Costa V.M.M., Simões S.V.D & Riet-Correa F. 2011. [Gastro-intestinal nematodes control in goats and sheep in the semiarid region northeastern Brazil.] Controle das parasitoses gastrintestinais em ovinos e caprinos na região semiárida do Nordeste do Brasil. Pesquisa Veterinária Brasileira 31(1):65-71. Hospital Veterinário, Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Patos, PB 58700-970, Brazil. E-mail: valery.medeiros@hotmail.com This paper reviews some important concepts to be considered for the control of gastro-intestinal nematode parasites of sheep and goats, including the epidemiology of this parasitic disease in the Brazilian semiarid, and the occurrence of anti-helminthic resistance in the region. Considering the widespread use of preventive treatments during the dry season, new alternatives for the control of gastrointestinal parasites are recommended, taking into account the parasite integrated control system and the use of methods to allow the presence of susceptible parasites in the refugia. Differences between sheep and goats are discussed, taking into account the higher susceptibility of goats and the necessity to use larger doses in goats than in sheep for most anti-helminthics.

• Anti-helminthics gastrointestinal nematodes anti-helminthic resistance anti-helmínticos nematódeos gastrintestinais resistência anti-helmíntica

Abstract in Portuguese:

RESUMO.- Costa V.M.M., Simões S.V.D & Riet-Correa F. 2011. [Gastro-intestinal nematodes control in goats and sheep in the semiarid region northeastern Brazil.] Controle das parasitoses gastrintestinais em ovinos e caprinos na região semiárida do Nordeste do Brasil. Pesquisa Veterinária Brasileira 31(1):65-71. Hospital Veterinário, Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Patos, PB 58700-970, Brazil. E-mail: valery.medeiros@hotmail.com Neste artigo são revisados alguns conceitos importantes a serem considerados para o controle de parasitas gastrintestinais em caprinos e ovinos. Descrevem-se as características epidemiológicas desta parasitose no semiárido e o aparecimento de resistência aos anti-helmínticos na região. São propostas alternativas para o controle da doença levando em consideração, principalmente, a adoção de técnicas de controle integrado de parasitas com uma mudança nos sistemas de tratamento preventivo para sistemas que permitam a sobrevivência de parasitas susceptíveis na refugia. São discutidas as diferenças entre caprinos e ovinos, considerando que os caprinos são mais susceptíveis e que para maioria das drogas devem ser tratados com doses maiores.

Abstract in English:

ABSTRACT.- Lima W.C., Athayde A.C.R., Medeiros G.R., Lima D.A.S.D., Borburema J.B., Santos E.M., Vilela V.L.R. & Azevedo S.S. 2010. [Nematode resistant to some anthelmintics in dairy goats in Cariri Paraibano, Brazil.] Nematóides resistentes a alguns anti-helmínticos em rebanhos caprinos no Cariri Paraibano. Pesquisa Veterinária Brasileira 30(12):1003-1009. Curso de Pós-Graduação em Medicina Veterinária, Centro de Saúde e Tecnologia Rural, Campus de Patos da Universidade Federal de Campina Grande, Patos, PB 58700-000, Brazil. E-mail: atsocamil@yahoo.com.br The aim of this paper was to evaluate the resistance of nematodes to some anthelmintics in dairy goats in Cariri Paraibano, Brazil. A total of 144 female goats, over 8 months of age, were used in the dry season and 120 ones during the rainy season, divided into four groups: Group I untreated, Group II treated with albendazole 10%, Group III treated with ivermectin 1%, and Group IV treated with levamisole phosphate 18.8%, at doses recommended by the manufacturer. To evaluate the resistance, the reduction in egg count per gram of feces and the cultivation of larval helminths. The fecal samples were collected on the day of treatment and, after 7, 14 and 21 days of treatment. In the group treated with albendazole, 61%, 11% and 24% of efficiency was observed in the dry period, and 55%, 14% and 12% in the rainy season, at 7, 14, and 21 days respectively. In the group treated with ivermectin, efficacy was 14%, 70% and 66% for the dry period, and 76%, 34% and 71% for the rainy season, at 7, 14 and 21 days respectively. The group treated with phosphate Levamisole showed efficacy rates of 89%, 79% and 73% in the dry period, and 76%, 69% and 67% in the rainy season, at 7, 14 and 21 days. The results indicate that the gastrointestinal nematodes of some dairy goats in Cariri Paraibano are not sensitive to the active Albendazole, Levamisole and Ivermectin. During the study, presence of specimens of the genera Haemonchus, Trichostrongylus, Oesophagostomum and Strongyloides was identified.

• Albendazole anthelmintics ivermectin levamisole nematode resistance ivermectina resistência a anti-helmínticos

Abstract in Portuguese:

RESUMO.- Lima W.C., Athayde A.C.R., Medeiros G.R., Lima D.A.S.D., Borburema J.B., Santos E.M., Vilela V.L.R. & Azevedo S.S. 2010. [Nematode resistant to some anthelmintics in dairy goats in Cariri Paraibano, Brazil.] Nematóides resistentes a alguns anti-helmínticos em rebanhos caprinos no Cariri Paraibano. Pesquisa Veterinária Brasileira 30(12):1003-1009. Curso de Pós-Graduação em Medicina Veterinária, Centro de Saúde e Tecnologia Rural, Campus de Patos da Universidade Federal de Campina Grande, Patos, PB 58700-000, Brazil. E-mail: atsocamil@yahoo.com.br RESUMO.- Objetivou-se avaliar a resistência de nematódeos a alguns anti-helmínticos em rebanhos caprinos no Cariri Paraibano. Foram utilizados 144 animais no período seco e 120 animais no período chuvoso, fêmeas com idade acima de oito meses de vida e lactantes, distribuídos em 4 grupos: Grupo I não tratado, Grupo II tratado com albendazole a 10%, Grupo III tratado com ivermectina a 1% e Grupo IV tratado com fosfato de levamisole a 18,8%, nas doses recomendadas pelos fabricantes. Para avaliar a resistência, aplicou-se o teste de redução na contagem de ovos por grama de fezes (RCOF) e o cultivo de larvas de helmintos. As amostras fecais foram coletadas no dia do tratamento (dia base) e 7, 14 e 21 dias após o tratamento. No grupo tratado com Albendazole, observaram-se eficácias de 61%, 11% e 24% no período seco e de 55%, 14% e 12% no período chuvoso, aos 7, 14, e 21 dias, respectivamente. No grupo tratado com Ivermectina, a eficácia foi de 14%, 70% e 66% para o período seco, e de 76%, 34% e 71% para o período chuvoso, aos 7, 14 e 21 dias, respectivamente. O grupo tratado com fosfato de Levamisole apresentou percentuais de eficácia de 89%, 79% e 73% no período seco e de 76%, 69% e 67% no período chuvoso, aos 7, 14 e 21 dias, respectivamente. Os resultados obtidos indicam que os nematódeos gastrintestinais de alguns rebanhos caprinos no Cariri Paraibano não são sensíveis aos princípios ativos Albendazole, Levamisole e Ivermectina. Durante o período de estudo foi identificada a presença de parasitas dos gêneros Haemonchus, Trichostrongylus, Oesophagostomum e Strongyloides.

Abstract in English:

ABSTRACT.- Santos H.F., Flôres M.L., Lara V.M., Sá M.F., Battisti L. & Lovato L.T. 2010. [Cloacal microbiota identification and evaluation of the antimicrobial resistance in captive cracids from Rio Grande do Sul, Brazil.] Microbiota cloacal de cracídeos cativos no Rio Grande do Sul e sua susceptibilidade a antimicrobianos. Pesquisa Veterinária Brasileira 30(12)1077-1082. Centro de Ciências Rurais, Universidade Federal de Santa Maria, Camobi, Santa Maria, RS 97105-900, Brazil. E-mail: llovato@smail.ufsm.br Cracids are wildlife Galliformes which inhabits the America’s tropical forests. Fifty one cloacal swabs were collected from 10 different species of captive cracids from the Rio Grande do Sul State during 2007. The cloacal swab samples were submitted to bacterial isolation, identification and, subsequently; antimicrobial susceptibility testing. Ninety three bacterial isolates were obtained from the cracid population examined. The most prevalent among the isolates were Escherichia coli, and bacteria from the Staphylococcus and Streptococcus genera. All samples tested in this study were negative for Salmonella spp. The antimicrobial susceptibility tests showed that none of the 93 strains presented resistance to the antimicrobial imipinem. In addition, the lower percentages of resistance were observed against cloranfenicol and ciprofloxacine. The bacteria genus and species with the highest percentage of resistance to the different antimicrobials examined were E. coli, Serratia marcescens, Staphylococcus spp. and Streptococcus spp. In conclusion, the data presented in this article demonstrate that the cloacal microbiota of the reported cracid population is composed of several bacterial genera and species and multi-drug resistance may be a problem for the future, since some strains showed elevated percentage of resistance against several different antimicrobials.

• Antimicrobial resistance Cracidae cloacal microbiota resistência antimicrobiana microbiota cloacal

Abstract in Portuguese:

RESUMO.- Santos H.F., Flôres M.L., Lara V.M., Sá M.F., Battisti L. & Lovato L.T. 2010. [Cloacal microbiota identification and evaluation of the antimicrobial resistance in captive cracids from Rio Grande do Sul, Brazil.] Microbiota cloacal de cracídeos cativos no Rio Grande do Sul e sua susceptibilidade a antimicrobianos. Pesquisa Veterinária Brasileira 30(12)1077-1082. Centro de Ciências Rurais, Universidade Federal de Santa Maria, Camobi, Santa Maria, RS 97105-900, Brazil. E-mail: llovato@smail.ufsm.br Os cracídeos são aves silvestres que habitam as matas tropicais da América. Foram coletadas, no ano de 2007, amostras cloacais de 51 aves de dez espécies diferentes de cracídeos mantidos em cativeiros no Estado do Rio Grande do Sul. A partir dos swabs, colhidos assepticamente, foi realizado o isolamento e a caracterização bacteriana e o teste de susceptibilidade antimicrobiana dos isolados. Foram identificadas 93 cepas de bactérias. As bactérias mais frequentemente isoladas foram Escherichia coli, Staphylococcus spp. e Streptococcus spp. Todas as amostras foram negativas para o isolamento de Salmonella spp. O resultado do teste de sensibilidade mostrou que dentre as 93 cepas isoladas, todas foram sensíveis apenas ao imipinem. Adicionalmente, os menores percentuais de resistência foram observados frente ao cloranfenicol e ciprofloxacina. Os gêneros e espécies bacterianas com maior percentual de resistência a diferentes antibióticos testados foram Escherichia coli, Serratia marcescens, Staphylococcus aureus e Streptococcus spp. Com os resultados obtidos no presente trabalho, concluí-se, que a população de cracídeos estudada apresenta sua microbiota cloacal composta por vários gêneros e espécies bacterianas e que a multirresistencia pode ser um problema no futuro, uma vez que algumas cepas isoladas mostraram percentuais elevados de resistência a diferente antimicrobianos.

Abstract in English:

RESUMO.- Sczesny-Moraes E.A., Bianchin I., Silva K.F., Catto J.B., Honer M.R. & Paiva F. 2010. [Anthelmintic resistance of gastrointestinal nematodes in sheep, Mato Grosso do Sul, Brazil.] Resistência anti-helmíntica de nematóides gastrintestinais em ovinos, Mato Grosso do Sul. Pesquisa Veterinária Brasileira 30(3):229-236. Departamento de Patologia, Centro de Ciências Biológicas e da Saúde, Universidade Federal de Mato Grosso do Sul, Cidade Universitária, Campo Grande, MS 79070-900, Brazil. E-mail: eurico_sczesny@hotmail.com Entre os métodos de controle da verminose gastrintestinal em ovinos, a utilização de produtos químicos é o mais empregado. Porém, o uso indiscriminado e continuado desses produtos tem selecionado populações de helmintos resistentes aos anti-helmínticos, fenômeno relatado no mundo todo. Este trabalho teve como objetivo identificar as espécies de parasitos gastrintestinais e diagnosticar a situação da resistência anti-helmíntica em ovinos no Estado de Mato Grosso do Sul. Foram realizados testes de redução na contagem de ovos por grama de fezes (OPG) em rebanhos de dezesseis propriedades rurais; as sete formulações utilizadas continham as seguintes bases farmacológicas: Albendazol, Ivermectina, Levamisole, Triclorfon, Moxidectina, Closantel e uma contendo as três primeiras associadas. As espécies identificadas nas necropsias, em ovinos adultos, foram: Haemonchus contortus, Trichostrongylus colubriformis, Cooperia curticei, C. punctata, C. pectinata e Oesophagostomum columbianum; em ordem de prevalência. As formulações contendo Albendazol e Ivermectina não apresentaram eficácia na redução de OPG nos rebanhos testados, com médias de redução de 0,7 e -19,6%, respectivamente. Closantel apresentou eficácia média de 6,7%; Levamisole, Moxidectina e Triclorfon de 28,7, 26,8 e 65%, respectivamente; a associação das três bases (Albendazol, Ivermectina e Levamisole), uma média de eficácia de 55,8%. As percentagens médias de larvas infectantes recuperadas nas coproculturas, tanto no pré como no pós-tratamento, foram semelhantes; indicando que a resistência às bases testadas está presente em todas as espécies citadas, em maior ou menor intensidade. Os dois gêneros predominantemente resistentes são Haemonchus sp., com 86,9%; seguido por Trichostrongylus sp., com média de 47,5%; Strongyloides sp. 33,6%; Oesophagostomum, sp. 21,4% e Cooperia sp. 19,7%.

• Anthelmintic resistance nematodes Haemonchus contortus Trichostrongylus colubriformis Cooperia curticei C. punctata C. pectinata Oesophagostomum columbianum Closantel Levamisolee Moxidectin Trichlorfon Albendazole Ivermectin Levamizol

Abstract in Portuguese:

ABSTRACT.- Sczesny-Moraes E.A., Bianchin I., Silva K.F., Catto J.B., Honer M.R. & Paiva F. 2010. [Anthelmintic resistance of gastrointestinal nematodes in sheep, Mato Grosso do Sul, Brazil.] Resistência anti-helmíntica de nematóides gastrintestinais em ovinos, Mato Grosso do Sul. Pesquisa Veterinária Brasileira 30(3):229-236. Departamento de Patologia, Centro de Ciências Biológicas e da Saúde, Universidade Federal de Mato Grosso do Sul, Cidade Universitária, Campo Grande, MS 79070-900, Brazil. E-mail: eurico_sczesny@hotmail.com Among the methods of control of gastrointestinal worms in sheep, the use of chemicals is the most common. However, the continued, and indiscriminate, use of these products has selected populations of resistant helminths to anthelmintics, a phenomenon reported in the whole world. This study aimed to identify the species of gastrointestinal parasites and diagnose the status of anthelmintic resistance in sheep in the State of Mato Grosso do Sul Brazil. Feacal egg count reduction tests (FECRT) were performed in flocks of sixteen farms, and the seven formulations used contained the following pharmacological bases: Albendazole, Ivermectin, Levamizol, Trichlorfon, Moxidectin, Closantel and one containing the first three in association. The species identified at necropsy, in adult sheep, were: Haemonchus contortus, Trichostrongylus colubriformis, Cooperia curticei, C. punctata, C. pectinata and Oesophagostomum columbianum, in order of prevalence. The formulations containing Albendazole and Ivermectin did not show efficacy in reducing the EPG in the flocks tested, with average reductions of 0.7 and -19.6%, respectively. Closantel presented an average efficacy of 6.7%; Levamisolee, Moxidectin and Trichlorfon, 28.7, 26.8 and 65% respectively, the combination of three bases (Albendazole, Ivermectin and Levamizol), an average efficacy of 55.8 %. The average percentages of infective larvae recovered in the faecal cultures, pre and post treatment were similar, indicating that resistance to the bases tested is present in all species cited, to a greater or lesser degree. The two genera predominantly resistant are Haemonchus sp., with 86.9%, followed by Trichostrongylus sp., with an average of 47.5%, Strongyloides sp. 33.6%, Oesophagostomum sp. 21.4% and Cooperia sp. 19.7%.

Abstract in English:

ABSTRACT.- Rangel P. & Marin J.M. 2009. Analysis of Escherichia coli isolated from bovine mastitic milk. Pesquisa Veterinária Brasileira 29(5):363-368. Departamento de Morfologia, Estomatologia e Fisiologia, Faculdade de Odontologia de Ribeirão Preto, Universidade de São Paulo, Avenida do Café s/n, Campus USP, Ribeirão Preto, SP 14040-904, Brazil. E-mail: jmmarin@forp.usp.br Mastitis has been recognized for some time as the most costly disease in dairy herds. From February to November 2004, 670 samples of bovine mastitic milk from which 231 Escherichia coli strains were isolated, were collected from two Brazilian states. The strains were screened for the presence of Shiga toxin-producing (stx 1 and stx 2) and intimin (eae) genes. Twenty (8.6%) strains were detected by PCR to harbor the Shiga toxin genes (8 the stx 1 gene, 12 the stx 2 gene and none both of them). Two (0.8%) of the Escherichia coli strains studied were eae positive non Shiga toxin-producing. The strains were also examined for resistance to 12 antimicrobial agents. The predominantly observed resistance was to tetracycline (92.2%), streptomycin (90.4%), nalidixic acid (88.3%), amikacin (86.5%) and cephalothin (84.8%). Multidrug resistance was found among 152 isolates (65.8%).

• Escherichia coli mastitis antimicrobial agents multidrug resistance eae gene mastite agentes antimicrobianos resistência a antimicrobianos gene eae.

Abstract in Portuguese:

ABSTRACT.- Rangel P. & Marin J.M. 2009. Analysis of Escherichia coli isolated from bovine mastitic milk. Pesquisa Veterinária Brasileira 29(5):363-368. Departamento de Morfologia, Estomatologia e Fisiologia, Faculdade de Odontologia de Ribeirão Preto, Universidade de São Paulo, Avenida do Café s/n, Campus USP, Ribeirão Preto, SP 14040-904, Brazil. E-mail: jmmarin@forp.usp.br Mastitis has been recognized for some time as the most costly disease in dairy herds. From February to November 2004, 670 samples of bovine mastitic milk from which 231 Escherichia coli strains were isolated, were collected from two Brazilian states. The strains were screened for the presence of Shiga toxin-producing (stx 1 and stx 2) and intimin (eae) genes. Twenty (8.6%) strains were detected by PCR to harbor the Shiga toxin genes (8 the stx 1 gene, 12 the stx 2 gene and none both of them). Two (0.8%) of the Escherichia coli strains studied were eae positive non Shiga toxin-producing. The strains were also examined for resistance to 12 antimicrobial agents. The predominantly observed resistance was to tetracycline (92.2%), streptomycin (90.4%), nalidixic acid (88.3%), amikacin (86.5%) and cephalothin (84.8%). Multidrug resistance was found among 152 isolates (65.8%).

Abstract in English:

ABSTRACT.- Coelho S.M.O., Reinoso E., Pereira I.A., Soares L.C., Demo M., Bogni C & Souza M.M.S. 2009. Virulence factors and antimicrobial resistance in Staphylo-coccus aureus isolated from bovine mastitis in Rio de Janeiro. Pesquisa Veterinária Brasileira 29(5):369-374. Departamento de Microbiologia e Imunologia Veterinária, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: miliane@ufrrj.br The study was conducted to characterize pheno-genotypically the virulence factors and resistance pattern of Staphylococcus aureus isolates from milk samples of cows with subclinical mastitis. All hemolytic isolates presented beta-hemolysin, and 38% of the non-hemolytic isolates were able to express hemolysins in the presence of a beta-hemolytic strain. The amplification of the coa-gene displayed four different size polymorphisms with about 400 bp, 600 bp, 700 bp and 900 bp. The spaA gene that encodes the IgG-binding region of protein A revealed sizes of 700 bp and 900 bp. The amplification of region X from spaA yielded a single amplicon for each isolate with the prevalent amplicon size being of 180 bp. Amplification of sae gene yielded an amplicon size of 920 bp in 71% of the isolates. Antibiotic resistance pattern revealed that 42% S. aureus were susceptible to all antimicrobials tested. Seven different antibiotic patterns were observed. Our results indicated that 47% and 25% of S. aureus strains exhibited resistance to penicillin and oxacillin respectively. All oxacillin-resistant isolates were mecA-positive.

• Staphylococcus aureus antimicrobial resistance virulence factors resistência antimicrobiana fatores de virulência

Abstract in Portuguese:

ABSTRACT.- Coelho S.M.O., Reinoso E., Pereira I.A., Soares L.C., Demo M., Bogni C & Souza M.M.S. 2009. Virulence factors and antimicrobial resistance in Staphylo-coccus aureus isolated from bovine mastitis in Rio de Janeiro. Pesquisa Veterinária Brasileira 29(5):369-374. Departamento de Microbiologia e Imunologia Veterinária, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: miliane@ufrrj.br The study was conducted to characterize pheno-genotypically the virulence factors and resistance pattern of Staphylococcus aureus isolates from milk samples of cows with subclinical mastitis. All hemolytic isolates presented beta-hemolysin, and 38% of the non-hemolytic isolates were able to express hemolysins in the presence of a beta-hemolytic strain. The amplification of the coa-gene displayed four different size polymorphisms with about 400 bp, 600 bp, 700 bp and 900 bp. The spaA gene that encodes the IgG-binding region of protein A revealed sizes of 700 bp and 900 bp. The amplification of region X from spaA yielded a single amplicon for each isolate with the prevalent amplicon size being of 180 bp. Amplification of sae gene yielded an amplicon size of 920 bp in 71% of the isolates. Antibiotic resistance pattern revealed that 42% S. aureus were susceptible to all antimicrobials tested. Seven different antibiotic patterns were observed. Our results indicated that 47% and 25% of S. aureus strains exhibited resistance to penicillin and oxacillin respectively. All oxacillin-resistant isolates were mecA-positive.

Abstract in English:

ABSTRACT.- Sampaio R.S., Lacerda M.S., Oliveira P.C.L., Paneto J.C.C., Bittar E.R., Borges G.A., Camacho G.M.M. & Braga E.M. 2009. [Variation of the resistance force to the micro-traction of fragments of cortical bones preserved in several means and fresh: Experimental study in rabbits.] Variação da força de resistência à micro-tração de fragmentos de ossos corticais preservados e a fresco: estudo experimental em coelhos. Pesquisa Veterinária Brasileira 29(4):345-352. Instituto de Estudos Avançados em Veterinária “José Caetano Borges”, Universidade de Uberaba, Av. Afrânio Azevedo 2140, Bairro Olinda, Uberaba, MG 38020-450, Brazil. E-mail: relisampa@terra.com.br Due to the increasing use of cortical bone allografts in orthopedic surgeries, de knowledge of its biomechanics characteristics during preservation time is needed. The present study consisted in the analyses of the resistance power to the micro-traction of samples of rabbit cortical bones preserved in several means for up to 180 days and fresh. The results showed that the resistance and the preservation time presented an inversely proportional relation, meaning that, the longer the time of preservation, the shorter the physical resistance evaluated in the biomechanical rehearsal of resistance to the micro-traction. The glycerin has presented lower values in relation to the resistance test, showing, after 30 days, only 24.58% of the present power in the fresh bone, and by 180 days, 1.76%. The samples submitted to autoclavation also showed low values by the end of the experiment, while they remained with just 12.31% of the power present in the fresh bone. The bones preserved in homologous plasma, Dakin liquid and the ones cryopreserved showed the best levels of resistance at the end of the experiment, remaining, respectively with 82.47, 70.34 and 66.72% of the maximum power, while compared with the resistance of the fresh bones. The conclusion is that the choice of methodology and time of preservation interfered directly in the biomechanics of the cortical bones, promoting decrease of the resistance capacity to the traction along the period of preservation.

• Bone graft bone preservation bone resistance bone micro-traction rabbits

Abstract in Portuguese:

ABSTRACT.- Sampaio R.S., Lacerda M.S., Oliveira P.C.L., Paneto J.C.C., Bittar E.R., Borges G.A., Camacho G.M.M. & Braga E.M. 2009. [Variation of the resistance force to the micro-traction of fragments of cortical bones preserved in several means and fresh: Experimental study in rabbits.] Variação da força de resistência à micro-tração de fragmentos de ossos corticais preservados e a fresco: estudo experimental em coelhos. Pesquisa Veterinária Brasileira 29(4):345-352. Instituto de Estudos Avançados em Veterinária “José Caetano Borges”, Universidade de Uberaba, Av. Afrânio Azevedo 2140, Bairro Olinda, Uberaba, MG 38020-450, Brazil. E-mail: relisampa@terra.com.br Due to the increasing use of cortical bone allografts in orthopedic surgeries, de knowledge of its biomechanics characteristics during preservation time is needed. The present study consisted in the analyses of the resistance power to the micro-traction of samples of rabbit cortical bones preserved in several means for up to 180 days and fresh. The results showed that the resistance and the preservation time presented an inversely proportional relation, meaning that, the longer the time of preservation, the shorter the physical resistance evaluated in the biomechanical rehearsal of resistance to the micro-traction. The glycerin has presented lower values in relation to the resistance test, showing, after 30 days, only 24.58% of the present power in the fresh bone, and by 180 days, 1.76%. The samples submitted to autoclavation also showed low values by the end of the experiment, while they remained with just 12.31% of the power present in the fresh bone. The bones preserved in homologous plasma, Dakin liquid and the ones cryopreserved showed the best levels of resistance at the end of the experiment, remaining, respectively with 82.47, 70.34 and 66.72% of the maximum power, while compared with the resistance of the fresh bones. The conclusion is that the choice of methodology and time of preservation interfered directly in the biomechanics of the cortical bones, promoting decrease of the resistance capacity to the traction along the period of preservation.

Abstract in English:

ABSTRACT.- Costa M.M., Silva M.S., Spricigo D.A., Witt N.M., Marchioro S.B., Kolling L. & Vargas A.P.C. 2006. [Epidemiology, molecular characterization and resistance to antimicrobials of Escherichia coli isolated from South-Brazilian pig herds.] Caracterização epidemiológica, molecular e perfil de resistência aos antimicrobianos de Escherichia coli isoladas de criatórios suínos do Sul do Brasil. Pesquisa Veterinária Brasileira 26(1):5-8. Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: agueda@ccr.ufsm.br Colibacillosis is an enteric disease with a major impact to the swine industry and is caused by enterotoxigenic strains of Escherichia coli. Forty clinical isolates from pigs with diarrhea and 13 environmental isolates were analysed regarding their genotypic profile, genetic relationship and antibiotic resistance. The most prevalent gene was Stb, identified in 50% of the isolates from clinical cases, and Sta and Lt were detected in 35% of them. Among the adesine factors investigated, F18 was found in 27.5% of the E. coli strains. The ERIC-PCR technique used for epidemiological characterization of the isolates did not show the expected discriminatory power. However, the test allowed separation of the isolates in groups, but did not evidence groups related to virulence factors. In the susceptibility test, the highest values for resistance were to tetracycline, in 88.6%. The index of multiple resistance to antimicrobials varied from 0 to 0.69.

• Escherichia coli genotypic profile resistance.

Abstract in Portuguese:

ABSTRACT.- Costa M.M., Silva M.S., Spricigo D.A., Witt N.M., Marchioro S.B., Kolling L. & Vargas A.P.C. 2006. [Epidemiology, molecular characterization and resistance to antimicrobials of Escherichia coli isolated from South-Brazilian pig herds.] Caracterização epidemiológica, molecular e perfil de resistência aos antimicrobianos de Escherichia coli isoladas de criatórios suínos do Sul do Brasil. Pesquisa Veterinária Brasileira 26(1):5-8. Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: agueda@ccr.ufsm.br Colibacillosis is an enteric disease with a major impact to the swine industry and is caused by enterotoxigenic strains of Escherichia coli. Forty clinical isolates from pigs with diarrhea and 13 environmental isolates were analysed regarding their genotypic profile, genetic relationship and antibiotic resistance. The most prevalent gene was Stb, identified in 50% of the isolates from clinical cases, and Sta and Lt were detected in 35% of them. Among the adesine factors investigated, F18 was found in 27.5% of the E. coli strains. The ERIC-PCR technique used for epidemiological characterization of the isolates did not show the expected discriminatory power. However, the test allowed separation of the isolates in groups, but did not evidence groups related to virulence factors. In the susceptibility test, the highest values for resistance were to tetracycline, in 88.6%. The index of multiple resistance to antimicrobials varied from 0 to 0.69.

Abstract in English:

Pereira M.S.V., Siqueira Júnior J.P. & Campos Takaki G.M. 2004. [Elimination of resistance to drugs by fluoroquinolones in bovine strains of Staphylococcus aureus.] Eliminação de resistência a drogas por fluorquinolonas em Staphylococcus aureus de origem bovina. Pesquisa Veterinária Brasileira 24(1):11-14. Depto Biologia Molecular, Centro de Ciências Exatas e da Natureza, Universidade Federal da Paraiba, João Pessoa, PB 58059-900, Brazil. E-mail: svieira@dbm.ufpb.br Bovine strains of Staphylococcus aureus were submitted to treatment with four fluoro-quinolones in subinhibitory concentrations (1/2 x MICs) to evaluate their influence on the curing of plasmids. Ciprofloxacin showed to be the most efficient by eliminating resistance to streptomycin, tetracyclin, penicillin, and cadmium nitrate. Norfloxacin and pefloxacin eliminated penicillin- and tetracyclin-resistance respectively. Otherwise, plasmids elimination by ofloxacin was not evidenced. The results obtained in this study confirm the potential of fluoroquinolones to eliminate antibiotic-resistant plasmids, and showed to be a valuable contribution for the prevention of multi-resistant strains, and may even enhance their sensitivity to other chemotherapeutic agents.

• Staphylococcus aureus fluoroquinolones elimination of resistance to drugs.

Abstract in Portuguese:

Pereira M.S.V., Siqueira Júnior J.P. & Campos Takaki G.M. 2004. [Elimination of resistance to drugs by fluoroquinolones in bovine strains of Staphylococcus aureus.] Eliminação de resistência a drogas por fluorquinolonas em Staphylococcus aureus de origem bovina. Pesquisa Veterinária Brasileira 24(1):11-14. Depto Biologia Molecular, Centro de Ciências Exatas e da Natureza, Universidade Federal da Paraiba, João Pessoa, PB 58059-900, Brazil. E-mail: svieira@dbm.ufpb.br Bovine strains of Staphylococcus aureus were submitted to treatment with four fluoro-quinolones in subinhibitory concentrations (1/2 x MICs) to evaluate their influence on the curing of plasmids. Ciprofloxacin showed to be the most efficient by eliminating resistance to streptomycin, tetracyclin, penicillin, and cadmium nitrate. Norfloxacin and pefloxacin eliminated penicillin- and tetracyclin-resistance respectively. Otherwise, plasmids elimination by ofloxacin was not evidenced. The results obtained in this study confirm the potential of fluoroquinolones to eliminate antibiotic-resistant plasmids, and showed to be a valuable contribution for the prevention of multi-resistant strains, and may even enhance their sensitivity to other chemotherapeutic agents.

Abstract in English:

ABSTRACT.- Molento M.B. & Prichard R.K. 2001. Effect of multidrug resistance modulators on the activity of ivermectin and moxidectin against selected strains of Haemonchus contortus infective larvae. [Efeito de drogas moduladoras da resistência múltipla na atividade da ivermectina e moxidectina contra larvas infectantes selecionadas de Haemonchus contortus.] Pesquisa Veterinária Brasileira, 21(3):117-121. Setor de Parasitologia, Universidade Paranaense, Umuarama, PR 87502-210, Brazil. E-mail: molento@unipar.br Nematode parasites have shown resistance to the anthelmintics, ivermectin and moxidectin, and there is evidence that the over-expression of parasite P-glycoprotein (P-gp) may account, at least in part, for resistance to ivermectin. The objective of this study was to evaluate whether the multidrug resistance (MDR) modulators, verapamil, CL 347.099 (an analog of verapamil) and cyclosporin A, would enhance the efficacy of ivermectin and moxidectin against selected strains of Haemonchus contortus using an in vitro larval migration assay. The modulators had no effects on the number of migrating larva e when used alone. lvermectin and moxidectin showed a significant (P<0.05) increase in its efficacy by 52.8 and 58.5% respectively, when used in association with verapamil against a moxidectin-selected strain. CL 347,099 also increased significantly (P<0.05) the ivermectin and moxidectin efficacy by 24.2 and 40.0% respectively, against an ivermectin-selected strain and by 40.0 and 75.6% respectively, against an moxidectinselected strain. At the concentrations tested cyclosporin A showed a variable effect on increasing the efficacy of the anthelmintics against the susceptible and resistant strains.

• Nematode multidrug resistance (MOR) ivermectin moxidectin modulators verapamil CL 347.099 cyclosporin A Nematóides resistência múltipla (MOR) ivermectina moxidectina moduladores verapamil ciclosporina A.

Abstract in Portuguese:

RESUMO.- Molento M.B. & Prichard R.K. 2001. Effect of multidrug resistance modulators on the activity of ivermectin and moxidectin against selected strains of Haemonchus contortus infective larvae. [Efeito de drogas moduladoras da resistência múltipla na atividade da ivermectina e moxidectina contra larvas infectantes selecionadas de Haemonchus contortus.] Pesquisa Veterinária Brasileira, 21(3):117-121. Setor de Parasitologia, Universidade Paranaense, Umuarama, PR 87502-210, Brazil. E-mail: molento@unipar.br Existem relatos demonstrando a resistência de nematóides aos anti-helmínticos, ivermectina e moxidectina. O aumento da expressão da glicoproteína-P (P-gp) no parasita pode contribuir para o desenvolvimento da resistência a ivermectina. O objetivo deste trabalho foi avaliar se o uso combinado dos moduladores de resistência múltipla, verapamil, CL 347.099 (um análogo do verapamil) e ciclosporina A associados a ivermectina ou moxidectina, aumenta a eficácia dos anti-helmínticos contra cepas selecionacllas de Haemonchus contortus, utilizando um experimento in vitro de migração de larvas. ivermectina e moxidectina apresentaram um aumento significativo (P<0,05) de sua eficácia em 52,8 e 58,5%, respectivamente, quando utilizadas em associação com o verapamil contra a cepa selecionada para moxidectina. CL 347.099 também aumentou significativamente (P<0,05) a eficácia de ivermectina e de moxidectina em 24,2 e 40,0%, respectivamente, contra a cepa selecionada para a ivermectina e em 40,0 e 75,6% respectivamente, contra a cepa selecionada para moxidectina. Nas concentrações testadas, ciclosporina A apresentou resultados variáveis quando combinada com os anti-helmínticos. Quando utilizados sozinhos, os moduladores não apresentarão efeito na redução do número de larvas.