Caracterização da resistência à ivermectina de um isolado de Haemonchus contortus em ovinos: se tiver subtitulo

The production of sheep, both in Brazil and worldwide, has shown significant growth in the last years but still has some obstacles to its development, among them are the low indexes caused by parasites, with emphasis on haemoncose. Among the control methods used in the fight against worms are the anthelmintics, and one of the most active principles in this traditional treatment is ivermectin. While being the tool of choice in the treatment of parasitic diseases, improper use of the same led to the emergence of resistant isolates, not only to ivermectin, as several other active principles of antiparasitic drugs

Toxicidade de petróleo bruto sobre microcrustáceo Daphnia similis em água de rio e água de produção de petróleo

Aquatic ecosystems are suffering many impacts caused by human activities resulting from the activities occurring around them. With technological progress observed in recent years, this environment has received large amounts of chemicals from industries, agriculture and urban area that affect the aquatic biota. Among these sources of contamination, the oil industry has contributed to the pollution of aquatic environments with both effluents as produced water well as oil spills and their derivatives having toxicity to various organisms. With all the environmental issues has increased concern about water quality and has been used ecotoxicological tests with aquatic organisms to ecosystems to assess the toxicity of chemicals present in the water. In this context the microcrustacea Daphnia similis stands out as a freshwater organism very representative of the aquatic fauna of rivers and high sensitivity to environmental impacts. Thus, the present study aimed to evaluate the lethal toxicity of crude oil and produced water on this microcrustacea. The results showed that the microcrustacea presented high sensitivity to contaminants primarily crude oil. There was also the influence of environmental variables pH and temperature on the survival of organisms

Estresse oxidativo em ovinos das raças Suffolk e Santa Inês experimentalmente infectados por Haemonchus contortus

Pós-graduação em Ciência Animal - FMVA

Avaliação das técnicas de criopreservação para manutenção de linhagens de Haemonchus contortus em laboratório

Pós-graduação em Medicina Veterinária - FCAV

Differentiation of Haemonchus placei from Haemonchus contortus by PCR and by morphometrics of adult parasites and third stage larvae

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Attempts to vaccinate ewes and their lambs against natural infection with Haemonchus contortus in a tropical environment

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The effects of Diet and corticosteroid-induced immune suppression during infection by Haemonchus contortus in lambs

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Entomofauna visitante das flores de Cassia spectabilis (L.) D C. (Leguminosae)

Realizaram-se estudos sobre sistemas de reprodução de Cassia spectabilis (L.) D C. (Leguminosae) observando-se a diversidade, freqüência e constância dos insetos visitantes em diferentes horários. Também testou-se a influência dos fatores ambientais em relação às visitas. Os resultados de polinização manual sugerem que C. spectabilis é autocompatível, porém, a xenogamia é o sistema de reprodução predominante. As inflorescências foram visitadas por uma grande quantidade de insetos, havendo predominância de abelhas. O horário de maior ocorrência dos insetos nas flores de C. spectabilis foi das 8 às 14 h e de menor ocorrência entre 7 e 8 h e das 17 às 18 h. Quanto ao comportamento dos insetos em relação à flor de C. spectabilis, observou-se que Xylocopa frontalis Olivier, X. suspecta Camargo & Moure, Bombus morio Swederus e Centris scopipes Friese possuem comportamento e morfologia adequados aos polinizadores legítimos; C. similis F., Oxaea flavescens Klug e Epicharis rustica flava Cockerell foram considerados polinizadores ocasionais. Pseudaugochloropsis graminea (F.), Tetragonisca angustula Latreille e A. mellifera L. foram considerados pilhadores. A polinização por vibração é o método usado pelas abelhas para coleta de pólen.

Controle de nematóides parasitos gastrintestinais por Arthrobotrys musiformis em ovinos naturalmente infestados mantidos em pastagens

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Eficácia anti-helmíntica comparativa da associação albendazole, levamisole e ivermectina à moxidectina em ovinos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Gastrointestinal nematode infection in beef cattle of different genetic groups in Brazil

Resistance to natural infection by gastrointestinal nematodes was compared in 67 female calves of the following genetic groups: Nelore (NX); 1/2 Senepol + 1/2 Nelore (SN); and 1/2 Aberdeen Angus + 1/2 Nelore (AN). The NX (n = 26), SN (n = 23) and AN (n = 18) animals were monitored for 14 months, during which they remained without treatment, allowed to graze in a tropical environment. Eggs per gram of feces (EPG), coprocultures and packed cell volume (PCV) were carried out monthly. No significant effects of the interaction between the genetic groups and month/year of collection and the genetic group on the EPG were found, but there was a significant influence of the month of collection (P < 0.01). The monthly PCV measurements did not differ for the animals of the three genetic groups and there was no association found between the EPG and PCV. The animals of the SN and NX groups showed similar numbers of EPG with results zero, while for the AN group these numbers were significantly lower (P < 0.05). Although the NX group had a large number of EPG with results zero, it also contained many animals with high counts, meaning this group had higher averages during the entire study period. The following nematode genera were found in the coprocultures: Haemonchus, Cooperia, Oesophagostomum and Trichostrongylus, the latter in smallest proportion. There was no significant difference between the genetic groups for averages of all parasites identified, except Cooperia, which were present in higher numbers in the animals of the NX group (P < 0.05). The results obtained in this experiment suggest that the use of Bos taurus x Bos indicus crossbreeds can be a good strategy to reduce the use of chemical control in Brazil. (C) 2009 Elsevier B.V. All rights reserved.

Contaminação da pastagem com larvas infectantes de nematoides gastrintestinais após o pastejo de ovelhas resistentes ou susceptíveis à verminose

O grau de contaminação da pastagem por larvas de terceiro estágio (L3) de nematoides gastrintestinais foi avaliado em piquetes pastejados por ovelhas resistentes ou susceptíveis à verminose. O experimento foi realizado de 23 de novembro de 2007 a 22 de julho de 2008. Inicialmente, realizou-se a contagem de ovos por grama de fezes (OPG) de amostras individuais de 130 ovelhas adultas da raça Bergamácia. Dessas, foram selecionadas as nove ovelhas com contagens mais elevadas de OPG (susceptíveis) e as 10 com as menores contagens (resistentes). As ovelhas resistentes apresentaram menor contagem de OPG, maiores valores de volume globular, de proteína plasmática total e de eosinófilos sanguíneos, do que as ovelhas susceptíveis. O peso também foi maior no grupo resistente. Na pastagem, foram identificadas larvas de Haemonchus spp., Trichostrongylus spp. e Oesophagostomum spp. em média, as quantidades de L3 de Haemonchus spp. e de Trichostrongylus spp., na pastagem, foram 2,19 e 2,31 vezes, respectivamente, maiores nos piquetes pastejados pelo grupo susceptível do que nos do grupo resistente. Portanto, os animais susceptíveis devem ser eliminados do rebanho a fim de reduzir a contaminação da pastagem e otimizar a profilaxia das infecções por nematoides gastrintestinais.

Field study on nematode resistance in Nelore-breed cattle

The present study evaluated Nelore cattle with different degrees of resistance to natural infections by gastrointestinal nematodes. One hundred weaned male cattle, 11-12 months of age, were kept on the same pasture and evaluated from October 2003 to February 2004. Faecal and blood samples were collected for parasitological, haematological and immunological tests. In February 2004, the 10 most resistant and the 10 most susceptible animals were selected based on individual means of nematode faecal egg counts (FEC). Such animals were slaughtered for worm burden determination and nematode species identification. The repeatability estimates for FEC (+/- S.D.), log-transformed FEC and packed-cell volume (PCV) in all animals were 0.3 (+/- 0.05), 0.26 (+/- 0.04) and 0.42 (+/- 0.05), respectively. The resistant group showed lower FEC and worm burdens than the susceptible group (P < 0.05). There were no significant differences between groups regarding mean body weight, weight gain, PCV and total serum protein values (P > 0.05). The resistant group showed higher total serum IgE levels (P < 0.05) and higher mean eosinophil blood counts. However, the latter was statistically significant only 42 days after the beginning of the study. Nematodes Cooperia punctata and Haemonchus placei were predominant and the correlation between Cooperia and Haemonchus burdens was 0.64 (P < 0.05), which indicated that animals presenting increased numbers of one of those genera probably had increased numbers of the other. The current study provides further evidence of IgE active role in nematode immunity and suggests that total serum IgE level might serve as an additional marker to select Nelore cattle that are responsive to H. placei and C. punctata infections. (C) 2007 Elsevier B.V. All rights reserved.

Anthelmintic resistance in cattle nematodes in northwestern São Paulo state, Brazil

The present study was carried out in the northwestern region of São Paulo State, Brazil, to determine the anthelmintic resistance status in cattle naturally infected with gastrointestinal nematodes. The anthelmintics tested were levamisole phosphate (Ripercol (R), Fort Dodge), albendazole sulphoxide (Ricobendazole, Fort Dodge), ivermectin (Ivomec (R), Merial) and moxidectin (Cydectin (R), Fort Dodge), administered at the doses recommended by the manufacturers. From April 2002 to May 2004, 25 cattle farms were evaluated. on each farm, steers were divided into treatment and control (not treated) groups based on fecal egg counts (FEC). Between 7 and 10 days after the anthelmintics administration, fecal samples were collected from each animal for post-treatment FEC. Fecal cultures from each group were also prepared for larval identification. After treatment, mean FEC reduction (FECR) in treatment groups (compared with control groups) was assessed on each farm. FECR was lower than 90% on 23 farms after ivermectin treatment. on 19 farms, FECR of 100% was recorded following moxidectin treatment; on the remaining 6, FECR ranged from 90% to 97.2%. After albendazole treatment, FECR was higher than 90% on 20 farms and ranged from 47.4% to 84.6% on other 5. After levamisole treatment, FECR was higher than 90% on 23 farms and equal to 47.4% and 73.7% on other 2 farms. Results indicated the presence of resistant Cooperia spp. and Haemonchus spp., especially to ivermectin; on some farms, resistance to albendazole and levamisole was also observed. (C) 2007 Elsevier B.V. All rights reserved.