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Melanin is a heteropolymer formed by the polymerization of phenolic and indolic compounds. It occurs in organisms across all biological kingdoms and has a range different of functions, thus indicating its important evolutionary role. The presence of melanin offers several protective advantages, including against ultraviolet radiation, traumatic damage, oxidative stress, extreme temperatures, and pressure. For many species of fungi, melanin also participates directly in the process of virulence and pathogenicity. These organisms can synthesize melanin in two main ways: using a substrate of endogenous origin, involving 1,8-dihydroxynaphthalene (DHN); alternatively, in an exogenous manner with the addition of L-3, 4-dihydroxyphenylalanine (L-DOPA or levodopa). As melanin is an amorphous and complex substance, its study requires expensive and inaccessible technologies and analyses are often difficult to perform with conventional biochemical techniques. As such, details about its chemical structure are not yet fully understood, particularly for nematophagous fungi that remain poorly studied. Thus, this review presents an overview of the different types of melanin, with an emphasis on fungi, and discusses the role of melanin in the biology and ecology of nematophagous fungi.

Introdução: A propriedade Haras Galopante, situada em São Francisco do Itabapoana – RJ, desconhece a eficácia da ivermectina que é o produto que vem sendo utilizado a alguns anos nos animais do seu plantel para controle das parasitoses. Diante a situação de resistência anti-helmíntica em equinos é de crucial importância buscar aqueles compostos anti-helmínticos eficazes. Objetivos : No caso do disofenol a estratégia é ampliar o leque de atuação do produto a uma nova espécie animal. Com isso fazer a avaliação da eficácia da ivermectina e outros compostos anti-helmínticos disponíveis no mercado contra a população de nematoides gastrintestinais do Haras Galopante. Metodologia: Com isso foram testados albendazol, ivermectina, fenbendazol, piperazina, pamoato de pirantel sendo utilizados entre 10 a 15 animais de acordo com produto testado. Exceção foi o disofenol por se tratar de um produto ainda sem precedentes para esta espécie animal e por questões de segurança usamos número menor de animais caso ocorra óbito. As fezes foram coletadas no momento e após sete dias do tratamento para avaliar a redução no número de ovos por grama de fezes (OPG). Além disto, foram feitas coproculturas para obtenção das larvas infectantes(L3) e identificação dos gêneros sobreviventes ao tratamento e detecção de larvas originárias de baixas contagens e/ou negativas do OPG. Resultados: Ciatostomíneos, Parascaris equorum e Oxyuris equi foram os nematoides observados no plantel durante o período da avaliação. A exceção da piperazina e pamoato de pirantel que tiveram eficácia, respectivamente, de 100 e 97,8%, os demais anti-helmínticos testados não foram eficazes.Conclusão: A recomendação é que para ser considerado eficaz o produto reduza ≥ 95% o OPG. Ivermectina foi o anti-helmíntico menos eficaz (48%).

Nematodes of the genus Libyostrongylus parasitize ostriches, causing high mortality rates. These nematodes are found in the proventriculus and ventriculus of ostriches, but little is known about their distribution and the possible anatomopathological changes they cause in the various regions of these organs. This paper describes the distribution and quantification of Libyostrongylus and pathological changes found in regions of the proventriculus and ventriculus of ostriches with high and low levels of both natural and experimental infection. Ostriches were necropsied and tissue samples from the distinct regions of both organs were analysed based on nematode counts and histopathology after staining with haematoxylin and eosin, Masson's trichrome or Alcian blue/PAS. The cranial and glandular regions of the proventriculus were the most parasitized. The ventriculus contained more nematodes in the caudal region. No macro- or microscopic pathological changes were observed in either of these organs of experimentally-infected birds. However, naturally-infected birds with high levels of infection presented proventriculus with macroscopic lesions and heterophilic infiltrates surrounding nematodes. In the glandular region of this organ, nematodes were located in the adenomeres of the secretory ducts, causing altered architecture and erosions and ulcerative lesions with damaged epithelium. Nematode eggs were found in the koilin layer of the middle and caudal regions of the ventriculus only of these birds. The pH of the regions assessed by Alcian blue/PAS staining changed from acidic in the proventriculus to more alkaline in the caudal region of the ventriculus. These data add knowledge to the biology of Libyostrongylus. RESEARCH HIGHLIGHTS The most parasitized areas were the cranial and glandular regions of the proventriculus. Naturally-infected birds with high levels of infection presented macro lesions in the proventriculus and damaged epithelium. Nematode eggs were found in the ventriculus. The proventriculus had an acidic pH, which turned alkaline towards the ventriculus.

Medicinal plants have been the focus of several studies due to their nematicide properties which can be used to control nematodes in sheep. No study has examined the morphological effects of Cymbopogon citratus on nematodes. Thus, this study evaluated the chemical composition, nematicidal activity and effects of C. citratus extracts on the morphology of eggs and infective larvae (L3) of sheep. Aqueous and methanolic extracts and fractions of C. citratus were obtained and analysed in vitro. The C. citratus extracts were effective against Haemonchus spp. and Trichostrongylus spp. larvae and eggs. Ten fractions were obtained from C. citratus, six of which had high ovicidal activity at 1000 μg mL−1, and two fractions had high activity at all tested concentrations. The phytochemical analysis identified the presence of compounds such as terpenoids, various ketones, esters, and fatty acids. The ultrastructural analysis showed deformations of the cuticle and wilting along the body of the nematodes at all concentrations. The muscular layer, intestinal cells and the mitochondria profile showed damage compared to the typical pattern. Ultra-thin sections of eggs treated with methanolic fractions of C. citratus presented modifications. This study showed the biological activity and effects of C. citratus on the gastrointestinal nematodes in sheep.

The Golden hamster has been gaining significance as a new experimental biomodel, finding use as a reliable diagnostic tool in biomedical research and for zoonosis. Authentic data in terms of digestibility, interactions among raw materials and essential nutrients, besides the influence exerted by various sterilization processes on animal behavior remain unclear. We aimed to assess the influence of sterilization, via autoclaving and irradiation, of pellet feeds prepared using salmon or linseed oil on the digestibility and plasma biochemical parameters in Golden hamsters. Randomized evaluations were conducted on 36 adult male Golden hamsters (Mesocricetus auratus), distributed in six treatments and six replications, namely: common salmon oil; radiated salmon; autoclaved salmon; common linseed oil; radiated linseed and autoclaved linseed. A remarkable effect of the sterilization was evident on the digestibility and protein solubility of the feed, which was lower for autoclaved diets. There was also a significant effect on blood parameters. Animals fed diets containing linseed oil showed lower blood glucose compared to the others. Thus, the inference reached was that while salmon and linseed oil can be used in laboratory hamster feeds, autoclaving disturbs the nutritional quality of the rations. Resumo O hamster Golden é um importante biomodelo utilizado na pesquisa biomédica e como meio de diagnóstico para zoonoses. Informações de qualidade, digestibilidade, interações das matérias primas e exigências nutricionais, assim como os efeitos decorrentes dos diferentes processos de esterilização sobre o desempenho animal ainda são desconhecidos. Objetivou-se com esse estudo avaliar os efeitos da esterilização por autoclavagem e irradiação de rações peletizadas, formuladas com óleo de salmão ou linhaça, sobre a digestibilidade e parâmetros bioquímicos plasmáticos de hamsters Golden. Foram avaliados 36 hamsters Golden (Mesocricetus auratus), machos adultos distribuídos em delineamento experimental inteiramente casualizado com seis tratamentos e seis repetições, a saber: óleo de salmão comum; salmão irradiada; salmão autoclavada; óleo de linhaça comum; linhaça irradiada e linhaça autoclavada. Houve efeito significativo da esterilização sobre a digestibilidade e solubilidade proteica da ração, que foi pior para as rações autoclavadas. Também houve efeito significativo sobre os parâmetros sanguíneos. Animais alimentados com rações contendo óleo de linhaça apresentaram glicemia mais baixa em comparação aos demais. Conclui-se que o óleo de salmão e linhaça pode ser utilizado em rações para hamsters de laboratório, porém a autoclavação interfere na qualidade nutricional das dietas.

Duddingtonia flagrans has been tested as an alternative parasite control, but data from in vitro experiments based on in vivo calculations describing nematophagous fungi predation in nematodes are restricted. The objective of this work was to determine the efficacy of D. flagrans against sheep nematode larvae in vitro using in vivo calculations. Fecal samples were introduced to fungi in different concentrations: 0.0/control; 0.05; 0.1; 0.2; 0.4; 0.8; 1.6; 3.2; and 6.4 g corresponding, respectively, to 583.000; 1.166.000; 2.332.000; 4.664.000; 9.328.000; 18.656.000; 37.312.000 and 74.624.000 chlamydospores/kg of body weight. The material was incubated for 14 days, before the larvae recovery (Assay 1). Assay 2 was carried out with the doses of 0.00625; 0.0125; and 0.025 g. The results showed a negative correlation between fungal concentrations and larval numbers for both assays. The fungus demonstrated an efficacy above 89% in both assays. Thus, we consider that the data from in vitro studies based on in vivo calculations may optimize the fungi quantities for field experiments. Resumo Duddingtonia flagrans tem sido testado como uma alternativa no controle de parasitos, entretanto, trabalhos in vitro da predação de nematoides por fungos nematófagos correlacionados com cálculos baseados para testes in vivo são restritos. O objetivo deste trabalho foi determinar a eficácia in vitro de D. flagrans contra larvas de nematoides de ovinos tendo como base cálculos in vivo. Amostras fecais receberam a adição do fungo em diferentes concentrações: 0.0/controle; 0,05; 0,1; 0,2; 0,4; 0,8; 1,6; 3,2 e 6,4 gramas correspondendo, respectivamente, às seguintes dosagens: 583.000; 1.166.000; 2.332.000; 4.664.000; 9.328.000; 18.656.000; 37.312.000 e 74.624.000 clamidósporos/Kg de peso vivo animal. O material foi incubado por 14 dias, para recuperação das larvas (Ensaio 1). O Ensaio 2 foi realizado com concentrações de 0,00625; 0,0125 e 0,025 g. Foi observada correlação negativa entre a concentração fúngica e o número de larvas, nos dois ensaios. O fungo demonstrou eficácia acima de 89% em ambos os ensaios. A partir destes dados, acreditamos que ensaios in vitro baseados em cálculos in vivo podem aprimorar as dosagens para a realização de experimentos a campo.

The aim here is to present data on the efficacy of anthelmintics in sheep flocks in Rio de Janeiro, Brazil, and to discuss the interpretation of the fecal egg count reduction test (FECRT) for each nematode genus. Fecal eggs counts and pre- and post-treatment coprocultures were performed, the former to evaluate the efficacy of and the latter to determine the overall parasite prevalence. An additional efficacy test was performed at Farm # 1 a year after the initial test. Severe anthelmintic resistance was found for the flocks, with no FECRT sensitivity at any of the 22 farms evaluated. However, an analysis of the infective larvae showed that some drugs were effective against certain parasitic genera; i.e., levamisole was more effective against Haemonchus spp. and moxidectin against Trichostrongylus spp. In the additional FECRT performed at Farm # 1, moxidectin and nitroxynil were ineffective separately, but when applied in combination they were highly effective due to their efficacy against Haemonchus (nitroxynil) and Trichostrongylus (moxidectin), respectively. The use of the FECRT targeting the parasitic nematode species prevalent on farms may make it possible to choose more effective anthelmintics. Resumo O objetivo deste trabalho foi apresentar dados sobre a eficácia de anti-helmínticos em rebanhos ovinos no Rio de Janeiro, Brasil, e discutir a interpretação do teste de redução da contagem de ovos nas fezes (TRCOF) para cada gênero de nematoide. A contagem de ovos fecais (OPG) e coprocultura pré e pós-tratamento foram realizadas para avaliar a eficácia e a prevalência geral do parasito, respectivamente. Um teste de eficácia adicional foi realizado na Fazenda # 1 após um ano do teste inicial. Resistência anti-helmíntica grave foi encontrada, não havendo sensibilidade no TRCOF em nenhuma das 22 fazendas avaliadas. No entanto, na análise das larvas infectantes observou-se que algumas drogas foram eficazes contra certos gêneros parasitários; por exemplo, o levamisol foi mais eficaz contra Haemonchus spp. e a moxidectina contra Trichostrongylus spp. No TRCOF adicional realizado na Fazenda 1, a moxidectina e o nitroxinil foram ineficazes separadamente, mas quando aplicados em combinação, foram altamente eficazes devido à sua eficácia contra Haemonchus spp. (nitroxinil) e Trichostrongylus spp. (moxidectina), respectivamente. O TRCOF visando às espécies de nematoides parasitas prevalentes nas fazendas pode possibilitar a escolha de anti-helmínticos mais eficazes.

Standard diagnostic methods currently in use for the identification of helminth infections in ruminants are based on the morphological analysis of immature and adult stages of parasites. This paper describes a method for the semiquantitative identification of nematodes, mainly Trichostrongyloidea, at species-level resolution. The method is based on amplification and fragment analysis followed by minisequencing of the ITS-2 region (internal transcribed spacer 2) of the ribosomal DNA of parasite eggs or larvae. This method allows for the identification of seven genera (Chabertia, Cooperia, Haemonchus, Oesophagostomum, Ostertagia, Teladorsagia, and Trichostrongylus) and 12 species (Chabertia ovina, Cooperia curticei, Cooperia punctata, Cooperia oncophora/Cooperia surnabada, Haemonchus contortus, Haemonchus placei, Haemonchus longistipes, Oesophagostomum asperum, Oesophagostomum radiatum, Ostertagia ostertagi, Trichostrongylus axei, and Trichostrongylus colubriformis) of infectious nematodes of domestic ruminants. The concordance between the morphological and molecular analyses in the detection of genera ranged from 0.84 to 0.99, suggesting the proposed detection method is specific, semiquantitative, less laborious, and highly cost-efficient.

We describe the synthesis and a function of melanin in Duddingtonia flagrans, a nematode-trapping fungus. We tested various culture media treated with L-DOPA, glucose and tricyclazole on fungal growth and melanin distribution using infrared spectroscopy (IS), electron paramagnetic resonance (EPR) and transmission electron microscopy (TEM). In vitro rumen digestion was used to test the environmental stress and then to evaluate the capacity of this fungus to trap nematode larvae. The growth and melanization of the fungus after 21 days of incubation at 30°C were best in Sabouraud dextrose medium. IS indicated the presence of melanin in D. flagrans, with similar bands for commercial melanin used as a control, and assigned the values obtained by EPR (g of 2.0051 ± 0.0001) to the production of melanin by the fungus. TEM indicated that melanin was produced in melanosomes but was not totally inhibited by tricyclazole. Within the limits of experimental error, the predatory activity of fungus treated with tricyclazole was drastically affected after 27 h of in vitro anaerobic stress with rumen inoculum. The deposition of melanin particles on the fungal cell wall contributed to the maintenance of D. flagrans predatory abilities after in vitro anaerobic ruminal stress.

Horses can harbor a large amount of parasites that may cause serious clinical signs even death. The aim of this study was to evaluate the predatory activity of the fungus Duddingtonia flagrans against infective larvae (L3) of gastrointestinal nematodes of horses in fecal culture. The experimental design was completely randomized with three treated groups (G1, G2 and G3) and one control (CG), using eight animals/group. The treated animals received G1: 1.5 × 105; G2: 3 × 105 and G3: 6 × 105 chlamydospores of D. flagrans/kg body weight during 21 days. The fungi preparation was given at every other three-day interval. Faecal samples were collected during 30 days, on the same interval, to perform the fecal egg counts (EPG) and fecal culture for each horse. All groups demonstrated similar results for the EPG (P > 0.05) counts. D. flagrans significantly reduced (P

O controle das infecções causadas por parasitos em equinos, em especial grandes e pequenos estrôngilos, desperta grande preocupação, pois estes podem causar graves prejuízos, ocasionando inclusive a morte dos animais acometidos. Somado a isto, o controle utilizado em criatórios baseia-se no uso intensivo de compostos químicos e sem associação com outras formas de controle, acelerando a seleção de populações parasitárias resistentes. Assim, existe a necessidade de métodos alternativos para o controle das infecções parasitárias em equinos. O controle biológico realizado com o fungo Duddingtonia flagrans tem apresentado resultados promissores. O fungo é capaz de resistir à passagem pelo trato gastrintestinal de equinos e desenvolver-se no material fecal, exercendo sua atividade predatória sobre estágios larvares de parasitos. Seu uso pode promover como consequência, a redução do número de larvas infectantes presentes na pastagem e uma menor taxa de reinfecção dos animais. Acreditamos que esta estratégia de controle parasitário para equinos possa ser associada a um programa sanitário integrado, reduzindo à dependência de anti-helmínticos químicos e a seleção para nematoides resistentes. Esta revisão tem o objetivo de abordar os principais helmintos em equinos e suas formas de controle, ressaltando o potencial de D. flagrans como alternativa no controle biológico dos parasitos.

The nematode-trapping fungus Duddingtonia flagrans has been studied as a possible control method for gastrointestinal nematodes of livestock animals. These fungi capture and infect the nematode by cuticle penetration, immobilization, and digestion of the internal contents. It has been suggested that this sequence of events occurs by a combination of physical and enzymatical activities. The aim of this study was to investigate the participation of proteolytic enzymatic activity during the interaction of the nematophagous fungus D. flagrans with infective larvae of trichostrongylides and the free-living nematode Panagrellus spp. Protease inhibitors used interfered in the predatory activity of D. flagrans. However, only PMSF significantly reduced the mean number of Panagrellus spp. captured by D. flagrans in comparison with the control. The experiment with fluorogenic substrate showed that maximum urokinase activity during the interaction of the fungus with the infective larvae of trichostrongylides or Panagrellus spp. occurred within 7 or 1 h of incubation, respectively. The protease activity, especially of the serine class, may be important during the interaction between the fungus and nematodes.

RESUMO O objetivo deste estudo foi avaliar a atividade predatória do fungo Duddingtonia flagrans contra larvas infectantes (L3) de nematoides gastrintestinais na pastagem e no bolo fecal de equinos, em um período de 21 dias. O delineamento experimental foi inteiramente ao acaso, com três grupos tratados (G1, G2 e G3) e um controle (C), com oito animais/grupo. Os tratados receberam 1,5x105; 3x105 e 6x105 clamidósporos de D. flagrans/kg-1peso vivo animal, G1, G2 e G3, respectivamente, durante 21 dias, com administração a cada três dias. Foram delimitadas 36 áreas de 1m2 cada, equivalendo a repetições em triplicata para cada grupo. As fezes foram coletadas dos animais nos dias 0 (D0), 15 (D15) e 30 (D30 = sete dias após a última administração dos tratamentos) e depositadas nessas áreas de pastagem. O número de larvas presentes nos bolos fecais e na pastagem foi avaliado após 14 e 21 dias de cada etapa de deposição. A avaliação da atividade predatória de D. flagrans na pastagem e nos bolos fecais demonstrou que a redução do número de L3 nos bolos fecais foi acompanhada pelo aumento da variável na pastagem. Não se constatou diferença significativa entre os grupos avaliados em decorrência da temperatura média registrada durante o período. As avaliações realizadas em um curto período podem ser insuficientes para a avaliação do efeito do fungo.

No presente trabalho são discutidos os fatores que influenciam a transmissão e a prevalência de parasitoses intestinais em comunidades de baixa renda do norte do Estado do Rio de Janeiro, levando-se em conta os resultados obtidos de 2004 a 2009 no âmbito do Programa Parasitoses do Norte Fluminense, desenvolvido em parceria entre a FIOCRUZ, UENF e diversas instituições de pesquisa e ensino superior do Rio de Janeiro. São abordadas sugestões para a redução da prevalência nestas comunidades, tomando-se por base o Plano Nacional de Vigilância e Controle das Enteroparasitoses, o Programa Saúde na Escola do Governo Federal, o Plano Nacional de Saúde Ambiental e a Resolução 54.19 de 2001 da Assembléia Mundial da Saúde, Organização Mundial da Saúde e as metas de desenvolvimento sustentável do Milênio.

Libyostrongylus dentatus and Libyostrongylus douglassii are haematophagous nematodes found in the proventriculus and the ventriculus of ostriches. Pathological damage leading to bird death has been attributed to L. douglassii. However, histopathology of the mixed infection has not been reported. The aim of the present work was to characterize the cellular inflammatory infiltrate found in the proventriculus of ostriches with a mixed infection. Analysis of the collected nematodes confirmed a mixed infection in the proventriculus of examined birds. Histopathological examination of the proventriculus showed an inflammatory infiltrate composed of granular cells in close proximity to the nematodes. The granulocyte infiltrate was composed mainly of heterophils identified by the lack of peroxidase and presence of fusiform granules.

Duddingtonia flagrans, a nematode-trapping fungus, has been investigated as an agent for biological control against infective larvae of gastrointestinal nematode parasites of production animals. The initial process of nematode-trapping fungi infection is based on an interaction between the trap structure of the fungus and the surface of the nematode cuticle. This report investigates by light and scanning electron microscopy the kinetics of capture and infection during the interaction of D. flagrans with the infective larvae (L(3)) of trichostrongylides and the free-living nematode Panagrellus sp. D. flagrans was cultivated for 7 days in a Petri dish containing agar-water. L(3) and Panagrellus sp. were inoculated in the Petri dishes and the samples consisting of agar-L(3)-fungi and agar-Panagrellus sp.-fungi were collected after 10, 20, 30, 40, 50, 60, and 70 min and 3, 4, 5, 10, 15, 20, and 25 h of interaction. All samples were observed by light microscopy. The samples with 1, 5, 15, and 25 h of interaction were also analyzed by scanning electron microscopy. The interaction was monitored up to 25 h. An initial differentiation of predation structures was observed after 30 min of interaction. The presence of traps and of captured L(3) or Panagrellus sp. occurred after 70 min. The live captured nematodes were observed up to 3 h of interaction. However, after 4 h, all Panagrellus sp. were dead. It took 15 h of interaction for the fungus to invade the L(3), and the presence of hyphae inside the nematode near the region of penetration was evident. At this time, the hyphae had filled the whole body of Panagrellus sp. The complete occupation of the body of L(3) occurred at 20 h of interaction and with 25 h the nematode was completely damaged except for the cuticle. Although the double cuticle of L(3) slows the penetration of D. flagrans, it was possible to verify that the process of trap formation and capture occurs quickly when both nematodes were tested, suggesting that the organisms would eventually be killed once in contact with the fungi encouraging the use of the fungus as a biological control agent.

The use of Duddingtonia flagrans, a nematode-trapping fungus, has been investigated as a biological control method against free living larvae of gastrointestinal nematodes of livestock animals. This fungus captures and infects the nematode by cuticle penetration, immobilization and digestion of the internal contents. It has been suggested that this sequence of events occurs by a combination of physical and enzymatical activities. This report characterizes the acid phosphatase activity during the interaction of D. flagrans with the free-living nematode Panagrellus sp. The optimum pH for the hydrolysis of the acid phosphatase substrate p-nitrophenyl phosphate was 2.2, 2.8 and 5.4 from D. flagrans alone and 2.2 and 5.4 for Panagrellus sp alone, fungus-nematode interaction in liquid medium and fungus-nematode interaction in solid medium. Different acid phosphatase activity bands were detected by SDS-PAGE. Maximum acid phosphatase activity of the fungus or nematode alone and of the fungus-nematode interaction occurred within 70min of incubation in the presence of the substrate 4-methylumbelliferyl phosphate. The activity of this enzyme was significantly higher for the fungus-nematode interaction when compared to the organisms alone, indicating a synergistic response. Furthermore, structures appeared in the hyphae after 30min, nematodes were observed adhered after 40min and many were captured by the typical fungus traps after 70min of interaction. The participation of acid phosphatase activity and its importance during the interaction of the fungus with the nematode were discussed.

Anthelmintic resistance has emerged globally as a problem amongst nematode of livestock and has been particularly well documented in equine and small ruminants. There are no studies regarding the efficacy of anthelmintics against the hematophagous nematodes in ostriches, Libyostrongylus dentatus; and just a few on L. douglassii. Here the efficacy of albendazole, ivermectin and moxidectin were evaluated against these two species in an ostrich farm in Minas Gerais state, Brazil. The feces were collected on the day of treatment and after 13days of an oral dose of albendazole (6mg/kg), or an injected dose (0.2mg/kg) of ivermectin or moxidectin. The fecal egg count reduction test and coprocultures were performed to determine possible resistance against the drugs used. An efficacy of 60% was found for ivermectin, while albendazole and moxidectin were 100% effective. Both worm species appeared to have reduced sensitivity to ivermectin.

The effect of different temperatures on the predatory activity of Arthrobotrys oligospora and Duddingtonia flagrans on the free-living larval stages of cyathostomes were evaluated in an experiment where feces of horses containing the parasites’ eggs were treated with these fungi and incubated under different constant temperatures (10°C, 15°C, 20°C, 25°C and 30°C ). The results indicated that the optimum temperature for egg development was 25°C. At 10°C the number of L3 recovered was practically zero, and at 15°C and 20°C, the percentage of larvae recovered was less than 3% of the total number of eggs per gram of feces. When these cultures subsequently were incubated for an additional period of 14 days at 27°C, they allowed the development of L3. In all the cultures inoculated with fungi a significant reduction in the number of larvae was observed. When incubated at 25°C or 30°C, the fungi caused reductions above 90%, in the number of L3. The samples cultivated at 10°C, 15°C, 20°C, 25°C and 30°C, when incubated for an additional period of 14 days at 27°C the reduction percentage of larvae was above 90% for A. oligospora. However, the same did not occur for D. flagrans. Here a reduction percentage between 47.5% and 41.8% was recorded when the cultures were incubated at 10°C and 20°C, respectively. The two species of fungi tested showed to be efficient in reducing the number of L3 when mixed with equine feces and maintained at the same temperature for the development of larval pre-parasitic stages of cyathostomes. A atividade predatória de fungos nematófagos e o desenvolvimento de estádios pré-parasitários de nematódeos estrongilídeos são influenciados pela temperatura. O efeito de diferentes temperaturas constantes na atividade predatória dos fungos Arthrobotrys oligospora e Duddingtonia flagrans sobre as fases larvares de vida livre dos nematódeos ciatostomíneos foi avaliado em um experimento onde fezes de cavalos contendo ovos de parasitos foram tratadas com fungos e incubadas em diferentes temperaturas constantes (10°C, 15°C, 20°C, 25°C e 30°C). Os resultados indicaram que a temperatura ótima de desenvolvimento de ovo até L3 foi de 25°C. A 10°C o número de L3 recuperado foi praticamente zero e a 15°C e 20°C os percentuais obtidos foram inferiores a 3% do total do número de ovos por grama de fezes. Quando estes cultivos foram incubados por um período adicional de 14 dias à 27°C permitiram o desenvolvimento até L3. Em todos os cultivos inoculados com fungos, quando as larvas estavam presentes, houve redução significativa no número de larvas atribuído à ação predatória dos fungos. A 25°C e 30°C os fungos ocasionaram reduções acima de 90% no número de L3. Os cultivos mantidos à 10°C, 15°C, 20°C, 25°C e 30°C quando incubados por um período adicional de 14 dias na temperatura controle, mantiveram percentuais de redução larvar superior a 90% para o fungo A. oligospora, o mesmo não ocorrendo para D. flagrans, que apresentou percentuais de 47,5% e 41,8% quando estimulado a 10°C e 20°C, respectivamente. Esses fungos demonstraram ser eficientes na redução do número de L3 quando adicionados a fezes de eqüinos nas mesmas temperaturas ideais para o desenvolvimento dos estádios larvares pré-parasitários.

Libyostrongylus sp. are nematodes that infect ostriches. Libyostrongylus douglassii was first described in ostriches from several countries in the world. Later Libyostrongylus dentatus was morphologically identified in ostriches in the USA and Brazil, and mixed infection is common in the latter country. The internal transcribed spacer (ITS) region of the ribosomal DNA gene is used for genetic variability assessment and phylogenetic reconstruction for many organisms. Through genetic analysis the status of different species morphologically defined was confirmed and a molecular method was developed to differentiate both species. ITS1, 5.8S, ITS2 regions of L. douglassii and L. dentatus were characterized. Regarding complete ITS region, the K2-p genetic distance between the species was 0.060 (SE 0.008) and the intra-specific distance was 0.002 (SE 0.001) for L. dentatus and 0.006 (SE 0.002) for L. douglassii. NJ and MP phylogenetic analysis of ITS1 and ITS2 regions indicated that both species belong to the Trichostrongylidae family, and are evolutionarily different, suported by high bootstrap value. Based on ITS DNA polymorphisms, a molecular approach was designed to detect both species. These results are the first molecular characterization of L. douglassii and L. dentatus, and provide new tools for the identification of these parasites of veterinary importance.

SUMMARYIn a recent study by our group on the prevalence of intestinal parasitic infections and on the knowledge, attitudes and practices of local residents of Campos dos Goytacazes, Rio de Janeiro, Brazil, we observed that about 50% of the inhabitants were parasitized and had some knowledge of intestinal parasitic infections but did not apply this knowledge in daily practice. We were thus motivated to implement strategies in health education to promote preventive measures in the locality. The goal of the present work was to evaluate the influence of health education on the prevalence of intestinal parasitic infections in the region in an effort to strengthen public policies for controlling these diseases in Brazil. The methodology adopted was based on action-research and a theoretical framework of health promotion. Our results demonstrate that the study population exhibited an enhanced awareness of the importance of disease from intestinal parasitic infections. Attitudes and practices related to prevention were significantly improved after the shared health education. In conclusion, this study allowed the shared construction of knowledge that reflected the true needs of the residents.

Ostriches were imported to Brazil in the early 1990s without appropriate parasite control leading to a co-importation of parasites. Libyostrongylus douglassii, Libyostrongylus dentatus and Codiostomum struthionis are nematodes of the ostriches that have been reported on some Brazilian farms but no national survey has been performed. Moreover, little is known about anthelmintic usage to control these parasites in Brazil. Therefore, the occurrence of L. douglassii, L. dentatus and C. struthionis and the anthelmintic management practices in Brazilian ostrich farms were studied. A questionnaire about management practices and information on how to collect, store and ship feces to the laboratory were sent to 17 farms located in 9 Brazilian states. Received fecal samples were submitted to fecal cultivation and larval harvested. Infective larvae were morphologically analyzed and quantified. The majority of the farms (88%) used an anthelmintic at least once a year. Ivermectin was the principal anthelmintic. Libyostrongylus sp. and C. struthionis were found in samples from 76 and 18% of the examined farms, respectively. The presence of L. douglassii (61–97%) was higher than L. dentatus (3–57%) and C. struthionis (2–30%). At the farm level, both species of Libyostrongylus were always found together. Sheath tail measurements of their infective larvae were crucial for morphological diagnosis. L. dentatus and L. douglassii are well adapted to Brazil and are widely distributed in the Brazilian territory, proving that this mixed infection in Brazilian ostrich's farms is common.

Intestinal parasites are the causative agents of common infections responsible for significant public health problems in developing countries and generally linked to lack of sanitation, safe water, and improper hygiene. More than two billion people throughout the world live with unrelenting illness due to intestinal parasitic infections (IPIs). The purposes of this study are to assess knowledge, attitudes, and practices on IPIs and investigate the relationship with prevalence of intestinal parasites among a low-income group of inhabitants from two communities of the Travessao District area, Campos dos Goytacazes, north of Rio de Janeiro State, Brazil. The two communities are known as "Parque Santuario," which is an urban slum with miserable living conditions, and "Arraial," where the socioeconomic and educational levels are better, neither having a sanitary infrastructure with an excreta collection system. Questionnaires revealed that both communities had local and specific codification to denominate the intestinal parasites and present correct knowledge on the theme but ignored some aspects of IPI transmission, with the Arraial population being better informed (p < 0.05). The overall prevalence of IPIs in Parque Santuario (49.7%) was greater than in Arraial (27.2%) (p < 0.001; prevalence ratio/95% confidence interval 1.83/1.50-2.23). This study reports the real IPI situation in the Travessao District and also reinforces the need to continue the investigation on the impact of combined prophylactic methods, educational measures, and socioeconomic and sanitary improvements by governmental authorities and the local popular organization.

The introduction of exotic species can increase the risk of extinction of native species through the introduction of new diseases, predation or resource competition. The marmosets Callithrix penicillata and Callithrix jacchus and hybrids of these two species have been introduced to privately owned forests in the lowland Atlantic forest of the Rio de Janeiro State in Brazil, the region of occurrence of the endangered golden lion tamarin, Leontopithecus rosalia. Because the ecology and biology of the marmosets and tamarins is similar, there is a reasonable risk that the marmosets would transmit pathogens such as endo parasites. The objective of this study was to identify the helminth fauna present in the introduced marmosets through an analysis of fecal samples of wild caught animals, and to evaluate the parasitological profile according to age, sex and geographical location. Eggs belonging to the Acanthocephala and Nematoda were found in the feces. One nematode egg type was identified as being Primasubulura jacchi. The ocurrence of nematodes was higher in males, acanthocephala were found in all age groups and sexes and P. jacchi was found with higher frequency in adult females. The geographic distribution analysis revealed that some of the forests had a higher predominance of parasites. Little is known about the pathology of parasites in free living Neotropical mammals, and this knowledge would be necessary to infer about the risk (form a parasitological standpoint) that the marmoset presence represents for the survival of the endangered golden lion tamarin.

Anthelmintic resistance in parasites maybe a consequence of over-exposing populations of parasites to drugs or from the commerce/transit of animals harboring resistant parasites. Knowledge of the sensitivity of nematodes to anthelmintics is essential to establish an efficient integrated program of parasite control. In Brazil, producers rely on technology transfer from field professionals and non-technical labor for new management strategies of parasite control. The aim of this work was to determine the practices farmers used for anthelmintic management and to monitor drug efficacy on sheep farms from northern and northwestern regions of the state of Rio de Janeiro, Brazil. A questionnaire was sent to 34 farms, and anthelmintics were tested on ten of these farms. Sheep (n=10/group) were weighed and treated with albendazole, closantel, doramectin, fenbendazole, ivermectin, levamisole, moxidectin, or nitroxynil with their recommended doses. Faeces were collected on the day of treatment and after 7-10 days. The faecal egg count reduction test was evaluated based on RESO 2.0. Among the farmers interviewed, 97% applied commercial anthelmintics to control parasites, 77% rotated anthelmintics annually, 72% used ivermectin as the principal anthelmintic, and 38% applied anthelmintics with a frequency of 30-60 days. On two farms, none of the anthelmintics was efficacious. Levamisole had the best overall efficacy (70%). Albendazole, ivermectin, and fenbendazole were efficacious (above 95%) on only two farms. The present work illustrates the alarming lack of efficacy of drugs even in an area new to sheep farming. It is important to establish alternative strategies of management in a broad program of parasite control for reducing the selection pressure on parasites by the commercially available anthelmintics.

The differentiation of the species of the Libyostrongylus genus is only possible with the obtainment of the adult parasites in the ostriches proventriculus and gizzard. The present work confirms that it is possible to differentiate the infective larvae of L. douglassii and L. dentatus allowing the differential diagnosis of these species by fecal culture. To show this, adult females from both species were collected from ten proventriculus from adult ostriches and separated by species. Both groups were macerated individually added to sterilized feces for standard fecal cultures. The infective larvae were recovered, identified, quantified and measured. All proventriculus analyzed were parasitized by Libyostrongylus spp. and a clear heterogeneous location for each species was observed. The infective larvae from the fecal cultures of macerated L. douglassii presented a mean total length of 874.3+/-33.80 microm, and a short sheath tail (29.5+/-4.11 microm) with acute termination. The infective larvae from the macerated L. dentatus presented mean total length of 856.0+/-43.63 microm, long sheath tail (61.2+/-9.52 microm) with filamentous termination. The mean measures of the tails of both species had a significant difference. The differentiation of the infective larvae of L. douglassii and L. dentatus by fecal cultures will facilitate the diagnosis of both species for further understanding the Libyostrongylus biology.

The genus Libyostrongylus includes three species, L. douglassii, L. dentatus and L. magnus that occur as parasites in the proventriculus of Struthio camelus. We confirmed a mixed infection by L. douglassii and L. dentatus in farmed ostriches from the southeast of Brazil for the first time, and provided new information on some morphological characters that differentiate these species. Adult nematodes collected from the proventriculus of ostriches were observed by light and scanning electron microscopy. Morphologic characterization and morphometric analysis of the nematodes enabled the distinction of both species and corroborated results of prior studies. Specimens of L. dentatus have a buccal capsule with a prominent esophageal tooth. Furthermore, males and females of L. dentatus were larger (4954 and 9347 microm) than those of L. douglassii (3411 and 4229 microm), but measurements for most characters in both species were smaller then those previously reported. Besides, the cephalic structure based on scanning electron microscopy differs, and L. dentatus has thick lips with round papillae, whereas L. douglassii has fine lips with lengthened papillae. The confirmation of both species in South America strongly suggests that the mixed infection may be common in farmed ostriches.

Domestic production of ostrich in Brazil started in the beginning of the last decade, but its sanitary state has not been reported. Libyostrongylus sp. is an ostrich specific nematode whose parasitism can severely affect the birds. Thus, Libyostrongylus spp. larvae were identified in commercial ostriches in the north region of the state of Rio de Janeiro, Brazil. The EPG was determined and fecal cultivation was performed. The eggs presented typical characteristics of strongylid and were present in five out of six farms. The mean EPG varied from 22 to 2395 and Libyostrongylus spp. prevalence was from 0 to 100%, with adult birds more infected. Two types of infective larvae with tail finishing in a tipped spiny knob were distinguished. The first had a mean length of 848 microm (710-1010) with a long sheath tail of about 66 microm (52-112). The other had a mean length of 826 microm (620-940) with a short, more abruptly ending sheath tail of 32 microm (22-40) and a less rounded cephalic end. The differences between these larvae suggest two Libyostrongylus species.

RESUMO - O efeito da fermentação aeróbia na viabilidade de avos de nematódeos trichostrongilídeos foi avaliado em um sistema em que fezes de ovinos contendo ovos de Haemonchus contortus foram imersas em um tanque de fermentação dotado de aerador mecânico intermitente e fezes de bovinos com ovos de nematódeos trichostrongilídeos havendo predomínio de Cooperia sp. foram deixadas fermentar em depósitos a campo. Amostras dos ovos submetidas aos dois processos de fermentação foram colhidas em diferentes intervalos e cultivadas para extração das larvas infectantes. Ambos os processos de fermentação reduziram o número de ovos viáveis. Esterilização superior a 99% dos ovos foi obtida com 14 dias pós-exposição nos dois processos. ABSTRACT - The viability of gastrointestinal nematode eggs after aerobicfermentation was evaluated in two experiments. In the first, feces of sheep containing Haemonchus contorts eggs were submitted to aerobic fermentation by mechanical air pumping in a 300m³-capacity tank. In the second, bovine feces positive for eggs of the most common gastrointestinal nematodes were kept in a bovine fecal deposit in the field. Fecal samples from the two experiments were cultivated for the extraction of infective larvae. Both processes reduced the number of viable eggs. Reduction in the number of viable eggs were higher than 99% in both cases after 14 days of exposure. Made available in DSpace on 2022-08-22T14:20:35Z (GMT). No. of bitstreams: 1 Efeito-fermentacao-aerobia-na-viabilidade-ovos-nematodeos-trichostrongilideos.pdf: 1403944 bytes, checksum: d3a96cf1ea1bc365c25b4ad77d1a1d01 (MD5) Previous issue date: 1996

Gastrointestinal parasitism in horses can affect all categories with evident clinical signs. Control is made with the regular use of chemical products, which has cause resistance to all classes of drugs [1, 2]. New alternative control strategies are needed and biological control with the fungi Duddingtonia flagrans is an appropriate option. The fungi pass through the intestinal tract of the horse acting on the parasite free-living stages. The chlamydospores need to grow in particular environmental conditions for the hyphae to be able to predate the eggs and larvae [3]. The objective of this study was to evaluate the activity of D. flagrans against nematode parasites in naturally infected horses. The study was performed at the Sao Jose da Serra Stud in Pinhais, Brazil. Twenty Thoroughbred animals were divided based on their faecal egg count (EPG) values in 3 treatment groups and one control (n=5). Chlamydospores of a Brazilian isolate of the D. flagrans were orally administered together with grinded-corn at G1: 250.000, G2: 500.000, and G3: 1.000.000 per kilogram of live weight. The animals were treated daily during 5 days. Faecal samples were collected during the 5 days of treatment and 5 days after treatment for EPG counts, which was performed with a 1:25 concentration, individually, as well as the coproculture. Recovered larvae from coproculture were counted on triplicates from each sample, calculating the average and standard deviation. Statistical analysis was performed using Tukey test with GraphPad Prims 5 at 5% significance (P

RESUMO - Os efeitos ovicida e larvicida de quatro linhagens de Bacillus thuringiensis var. kurstaki foram estudados em bioensaio onde fezes de ovinos contendo ovos de Haemonchus contortus foram incubadas com cultivo em caldo nutritivo constituído por mais de 90% de esporos da bactéria. A cultura foi adicionada a fezes frescas e fezes incubadas por 24 e 48 horas. Após adição da cultura, as fezes eram homogeneizadas e incubadas a 27°C por sete dias. Após este período as larvas eram retiradas através da baermanização e preservadas em formalina para serem quantificadas posteriormente. Duas cepas ocasionaram reduções significativas quando o caldo foi adicionado a fezes frescas ou a fezes incubadas por 24 horas, enquanto uma delas reduziu significativamente o número de larvas recolhidas dos cultivos quando o caldo foi adicionado a fezes incubadas por 24 ou 48 horas. Uma das cepas ocasionou redução significativa apenas quando o caldo foi adicionado em fezes cultivadas por 48 horas. ABSTRACT - Ovicidal and larvicidal effect of Bacillus thuringiensis var. kurstaki on free living stages of trichostrongylid nematodes is being surveyed using a bioassay in which 48-72 hours culture broth (>90% of spores) of the bacteria is added to fresh feces or feces incubated previously for 24 or 48 hours. Treated feces were incubated at 27°C for seven days after which the larvae were recovered through baermanization and formalized for a later counting. Ovicidal effect was observed in two strains and larvacidal effect in four strains. Made available in DSpace on 2022-08-22T14:19:37Z (GMT). No. of bitstreams: 1 Efeito-quatro-linhagens-Bacillus-thuringiensis-em-ovos-e-larvas-de-Haemonchus-contortus.pdf: 558493 bytes, checksum: 481d5277e6c323bcbe4d7e274e448f63 (MD5) Previous issue date: 1994