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We evaluated the efficacy of Bioverm®, a commercial product containing Duddingtonia flagrans, on the control of buffalo (Bubalus bubalis) gastrointestinal nematodes. We randomly divided 12 buffaloes into two groups of six animals. In the treated group, each animal received a Bioverm®`s single dose of 1g (105 chlamydospores of D. flagrans) to 10 kg of live weight; in the control group, each animal received 1g of corn bran for each 10 kg of live weight as a placebo. Fecal samples were individually collected from 12, 24, 36, 48, 60 and 72 h after treatments. To examine 1) viability of chlamydospores passed through the gastrointestinal tract, 2 g of faeces and 1000 infective larvae (L3) were added to Petri dishes with 2% water-agar, and 2) to examine larval predation by D. flagrans during fecal cultures, 2000 L3 were added. In the Petri dishes, were observed significant reductions (p < 0.01) in the treated group after 48 (56.7%) and 60 h (91.5%). In the fecal cultures, significant reductions (p < 0.01) occurred in the treated group from 36 h (75%), with larval reduction up to 72 h. High larval predation rate occurred 60 h after Bioverm® administration. Bioverm® maintained viability and predation capacity after passage through the buffalo's gastrointestinal tract, showing efficacy on gastrointestinal nematodes.

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In the control of bovine worms, biological control by nematophagous fungi stands out, especially Pochoniachlamydosporia which causes the destruction of helminth eggs. This study aims to test the effectiveness of a formulation containing the nematophagous fungus Pochonia chlamydosporia isolated for the biological control of bovine nematodiosis. Twelve cattle were divided into two groups: control group (GC) and the group that received the formulation (GT). Feces and pasture samples were collected for the research of gastrointestinal nematodes. Lung worms and trematodes were investigated. The animals were weighed monthly. The averages of temperature and rainfall were recorded. The supply of the fungus Pochonia chlamydosporia was not effective in reducing the eggs per gram of feces of gastrointestinal nematodes (EPG) of the animals, not differing statistically (p > 0.05) between the groups. The mean values of larvae recovered in the pasture did not differ significantly (p > 0.05). The genus Haemonchus sp. was the most prevalent. There was no correlation between the number of larvae with temperature and rainfall (p > 0.05). There was a statistically significant difference (p < 0.05) in the penultimate weighing of the experiment. The formulation containing Pochonia chlamydosporia was not efficient in the biological control of bovine gastrointestinal nematodes.

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Biological control is considered one of the most used alternative measures to combat helminths of relevance in veterinary medicine and public health. Among these parasites, Toxocara canis stands out for its high prevalence and worldwide distribution, in addition to being the main cause of visceral larva migrans in man. The present work aimed the fungus Pochonia chlamydosporia (isolate Pc-10) on eggs of T. canis. In order to do this, fertile nematode eggs were obtained by dissection of adult females fertilized specimens. After obtaining the eggs, they were inserted into 24 well plates previously À lled with different concentrations of enzymatic extract of the fungus (100, 200, 400 and 500 µL). In addition, the behavior of P. chlamydosporia hyphae on Toxocara canis eggs was also observed in 2% wateragar medium (2% WA+ fungal isolate) when compared to the control group (2% WA + water). It was veriÀ ed ovicidal activity with the enzymatic extract of P. chlamydosporia at concentrations of 400 and 500 µL. At the same time, after 12 days of exposure of the T. canis eggs to P. chlamydosporia mycelia it was possible to observe the fungus action on eggshells, including penetration of the hyphae and colonization of the egg inside. The results conÀ rm the ovicidal potential of the fungus and suggest its applicability in toxocariasis control programs.(AU)

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Bioverm® (Duddingtonia flagrans) is a fungal formulation indicated for controlling gastrointestinal nematodes in ruminants and horses, which has recently been authorized for commercialization in Brazil. The objective was to determine the efficiency of Bioverm® against larvae of gastrointestinal nematodes after passage through the gastrointestinal tract of cattle. Twelve animals were used, divided into two groups. In the treated group, a single dose of 1 g of Bioverm® per 10 kg of live weight (containing 105 chlamydospores of D. flagrans) was provided for each animal. Fecal samples were obtained from the animals in each group at 12, 24, 36, 48, 60 and 72 hours after administration. In assay A, 2 g of feces were added to Petri dishes containing 2% agar-water medium. In assay B, coprocultures were performed. In both assays, the peak of larval predation occurred within 48 hours after administration of Bioverm®. In assay A, a significant larval reduction (P < 0.05) was seen at 48 h (88.2%). In assay B, significant reductions (P < 0.05) were seen at 36 h (43.7%) and 48 h (82.3%). Bioverm® showed high predatory capacity after passage through the gastrointestinal tract of cattle and was effective for controlling gastrointestinal nematodes.

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Cooperia, Haemonchus and Oesophagostomum are the genera of gastrointestinal parasitic nematodes most prevalent in cattle and constitute a serious problem in cattle breeding due to the impact they have on meat and milk production and the high costs of control measures. The objective of the present work was to evaluate the efficiency of Bioverm® (Duddingtonia flagrans) in the control of gastrointestinal parasitism of young cattle raised in the field, in the Central-West region of Brazil. The experiment was conducted on a farm located in the municipality of Jangada, MT, where 18 cattle, Nelore and Aberdeen Angus breeds, aged six to ten months, were randomly divided into two groups (treated group and control group) and distributed in paddocks of Brachiaria decumbens, naturally infested by larvae of gastrointestinal nematodes. The animals in the treated group received 1g of Bioverm® for each 10 kg of body weight, administered daily with commercial feed, throughout a period of six months. In the control group, each animal received 1 g of rice bran for each 10 kg of body weight, without Bioverm®, added to the feed. Stool and pasture samples were collected every two weeks. The treated group showed a significant reduction (p < 0.05) in values of eggs per gram of feces (EPG) and a significant gain of body weight (p < 0.05) when compared to the control group. The fungal formulation Bioverm® was effective in pasture decontamination and consequently in reducing the occurrence of reinfection by nematodes. The animals treated with Bioverm® showed a lower parasitic load and greater weight gain.

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The use of nematophagous fungi is an alternative for the biological control of nematodes in ruminants. In this study, the compatibility of joint growth of the fungi Monacrosporium sinense and Pochonia chlamydosporia and the joint nematicidal activity of these fungal isolates on bovine infective larvae were evaluated. For that, tests of direct confrontation, the effect of volatile compounds and antibiosis were conducted. In order to carry out the tests, the fungi were inoculated in potato dextrose agar culture medium and, after the incubation period, the growth of the colonies, the formation of an inhibition halo and the effect of volatile metabolites were verified. The compatibility between fungi isolates M. sinense and P. chlamydosporia was confirmed and the nematicidal evaluation proved the best effectiveness was when both were used together, with a 98.90% reduction in the number of bovine nematode infective larvae under in vitro conditions. It was concluded that M. sinense and P. chlamydosporia presented synergistic action, suggesting that the joint application of the fungi increases the effectiveness of biological control of bovine infective larvae.

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Abstract Bioverm® (Duddingtonia flagrans) is a fungal formulation indicated for controlling gastrointestinal nematodes in ruminants and horses, which has recently been authorized for commercialization in Brazil. The objective was to determine the efficiency of Bioverm® against larvae of gastrointestinal nematodes after passage through the gastrointestinal tract of cattle. Twelve animals were used, divided into two groups. In the treated group, a single dose of 1 g of Bioverm® per 10 kg of live weight (containing 105 chlamydospores of D. flagrans) was provided for each animal. Fecal samples were obtained from the animals in each group at 12, 24, 36, 48, 60 and 72 hours after administration. In assay A, 2 g of feces were added to Petri dishes containing 2% agar-water medium. In assay B, coprocultures were performed. In both assays, the peak of larval predation occurred within 48 hours after administration of Bioverm®. In assay A, a significant larval reduction (P < 0.05) was seen at 48 h (88.2%). In assay B, significant reductions (P < 0.05) were seen at 36 h (43.7%) and 48 h (82.3%). Bioverm® showed high predatory capacity after passage through the gastrointestinal tract of cattle and was effective for controlling gastrointestinal nematodes.

Resumo O Bioverm® (Duddingtonia flagrans) é uma formulação fúngica indicada para o controle de nematódeos gastrintestinais de ruminantes e equídeos, recentemente autorizado para a comercialização no Brasil. Objetivou-se determinar a eficiência do Bioverm® contra larvas de nematódeos gastrintestinais após a passagem pelo trato gastrintestinal de bovinos. Foram utilizados doze bovinos divididos em dois grupos. No grupo tratado, foi fornecida, por animal, a dose única de 1g (105 clamidósporos de D. flagrans) do Bioverm® para cada 10 kg de peso vivo. Foram obtidas amostras fecais dos animais de cada grupo a partir de 12, 24, 36, 48, 60 e 72 horas após a administração. No ensaio A, 2g de fezes foram adicionadas em placas de Petri contendo meio ágar-água 2%. No ensaio B, foram realizadas coproculturas. Em ambos os ensaios, o pico de predação larval ocorreu em 48 horas após a administração do Bioverm®. No ensaio A, houve redução larval significativa (P<0,05) em 48h (88,2%). No ensaio B, as reduções significativas (P<0,05) ocorreram em 36h (43,7%) e 48h (82,3%). O Bioverm® apresentou elevada capacidade predatória após a passagem pelo trato gastrintestinal de bovinos, sendo eficaz no controle dos nematódeos gastrintestinais.

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Didelphis aurita Wied-Neuwied, 1826 is a marsupial well adapted to anthropogenic activity and commonly found in urban areas of Brazil. Among the gastrointestinal parasites found in this opossum, protozoa of the genus Eimeria are frequently detected. This study investigated the biodiversity of Eimeria species infecting D. aurita in Southeastern Brazil, and provides morphological data on a newly discovered species of Eimeria. From January to June 2019, 43 D. aurita were captured, and their fecal samples were collected and evaluated by salt flotation; positive samples were allowed to sporulate in 2.5% potassium dichromate (K2Cr2O7), and detailed morphological measurements were performed to determine the species present. Thirty-two of forty-three (74.4%) opossums were infected with from one to five Eimeria spp. Four of the eimerians were described and named previously by others: Eimeria auritanensis, Eimeria caluromydis, Eimeria gambai, and Eimeria philanderi. Additionally, sporulated oocysts of a species new to science were detected. Oocysts of this new Eimeria species are spheroidal to subspheroidal, 21.7 × 20.7 (20-23 × 19-23), length/width (L/W) ratio 1.05, with a highly refractile polar granule, but lacking a micropyle and oocyst residuum. Sporocysts are ovoidal, 10.6 × 8.0 (9-12 × 7-9), L/W ratio 1.3, with a small, Stieda body and a sporocyst residuum of diffuse granules. Of the infected opossums, 5/32 (16%) were infected with only one Eimeria sp., 6/32 (19%) with two, 15/32 (47%) with three, 5/32 (16%) with four and 1/32 (3%) with five Eimerians.

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Variations in temperature can affect the development of nematophagous fungi, especially when they are used in the biological control of parasitic nematodes in the pastures where cattle are reared. The aim of this work was to evaluate the effects of temperature on the performance of nematophagous fungi in the biological control of bovine parasitic nematodes. The mycelial growth, chlamydospore production and nematicidal activity of Duddingtonia flagrans, Arthrobotrys cladodes and Pochonia chlamydosporia were evaluated at 15, 20, 25, 30 and 35°C. The fungal strains achieved mycelial growth, chlamydospore production and nematicidal activity on parasitic nematodes under all temperature conditions tested. The fungi showed higher growth at intermediate temperatures (20, 25 and 30°C) than at the extremes of 15 and 35°C. At 25 and 30°C, D. flagrans realized 96.8 and 94.5% nematicidal activity on bovine parasitic nematodes, respectively. Arthrobotrys cladodes effected nematicidal activity of 85.3 and 83.5%, at 20 and 25°C, respectively. At 20 and 30°C, P. chlamydosporia achieved nematicidal activity of 81.3 and 87.4%, respectively. The maximum chlamydospore production was reached at 20, 25 and 30°C for D. flagrans, at 20 and 25°C for A. cladodes and P. chlamydosporia. The results of this study demonstrated that the tested fungal strains of D. flagrans, A. cladodes and P. chlamydosporia, when used in the biological control of bovine parasitic nematodes, were not limited by in vitro temperature variations. Therefore, the use of these strains of fungi as biological control agents of parasitic nematodes is promising.

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This study aimed to evaluate the use of a sodium alginate matrix-pelletized formulation of Duddingtonia flagrans for biological control of gastrointestinal nematodiasis in feedlot goats in the semiarid region of Northeastern Brazil. We used 20 Saanen female goats (age, 4 months; average weight, 12 kg) that did not receive anthelmintic treatment and had counting of eggs per gram of faeces (EPGs) ≥ 500. The animals were divided into two groups: in group 1 (D. flagrans group), each animal received 3 g of pellets (0.6 g of D. flagrans mycelium) per 10 kg of body weight, twice a week, over 4 months; and in group 2 (control group), each animal received 3 g of pellets without fungus per 10 kg of body weight, twice a week, over 4 months. Each group was maintained in a separate 15-m2 stall. Larval cultures and measurements of weight, EPG, and packed cell volume (PCV) were performed every 15 days. We observed low EPG levels in the D. flagrans group throughout the experimental period, with a significant difference (p < 0.05) on day 30 and from day 60, having, at the end of the experiment, average OPG values of only 150, reduction of 92.3% when compared to control group. Haemonchus sp. was the most prevalent helminth in all larval cultures. The D. flagrans group showed a mean weight gain of 8.8 kg at the end of the experiment (p < 0.05), while the control group showed a mean weight gain of 4.8 kg. The best PCV results (p < 0.05) were also observed in the D. flagrans group from day 30. Thus, the use of D. flagrans pellets in a sodium alginate matrix was effective in controlling gastrointestinal nematodiasis of feedlot goats in the semiarid region of Northeastern Brazil.(AU)

Objetivou-se avaliar a utilização da formulação peletizada em matriz de alginato de sódio de Duddingtonia flagrans no controle biológico das nematodeoses gastrintestinais de caprinos mantidos em confinamento no semiárido do Nordeste brasileiro. Foram utilizados 20 caprinos da raça Saanen, fêmeas, com quatro meses de idade, média de peso de 12 kg, sem tratamento anti-helmíntico prévio e com contagem de ovos por grama de fezes (OPG) ≥ 500. Os animais foram divididos em dois grupos: grupo 1, cada animal recebeu na ração 3 g de péletes (0,6 g de micélio fúngico de D. flagrans) para cada 10 kg de peso vivo, duas vezes por semana, durante quatro meses; grupo 2, cada animal recebeu na ração 3 g de péletes sem fungos para cada 10 kg de peso vivo, duas vezes por semana, durante quatro meses, servindo como grupo controle. Cada grupo permaneceu em uma baia de 15 m2. Foram realizadas contagens de OPG, determinação de volume globular (VG), coproculturas e pesagem dos animais a cada 15 dias. Observaram-se baixos valores de OPG no grupo D. flagrans durante todo o experimento, com diferença significativa (p < 0,05) no dia 30 e a partir do dia 60, tendo, ao final do experimento, valores médios de OPG de apenas 150. No grupo Controle, a contagem final foi de 1950 OPG. Haemonchus sp. foi o gênero de helminto mais prevalente em todas as coproculturas. O grupo D. flagrans apresentou média de ganho de peso de 8,8 kg ao final do experimento e o grupo Controle, 4,8 kg (p < 0,05). Também foram observados os melhores índices de VG (p < 0,05) no grupo D. flagrans a partir do dia 30. Concluiu-se que a utilização de péletes em matriz de alginato de sódio de D. flagrans foi eficaz no controle das nematodeoses gastrintestinais de caprinos mantidos em confinamento no semiárido do Nordeste brasileiro.(AU)

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