An isolate of the nematophagous fungus Monacrosporium thaumasium for the control of cattle trichostrongyles in south-eastern Brazil.

A mycelial formulation in sodium alginate pellets of the nematophagous fungus Monacrosporium thaumasium (isolate NF34A) was assessed in the biological control of beef cattle trichostrongyles in tropical Brazil. Two groups of ten male Nellore calves aged 6 months, a fungus-treated group and a control group, were fed on a pasture of Brachiaria decumbens naturally infected with larvae of cattle trichostrongyles. The fungus-treated group received doses of sodium alginate mycelial pellets orally (1 g pellets (0.2 g fungus)/10 kg live weight) twice a week for 12 months. At the end of the study there was a significant reduction (P< 0.01) in the number of eggs per gram of faeces and coprocultures of the fungus-treated group--47.8% and 50.2%, respectively--in relation to the control group. There was a 47.3% reduction in herbage samples, collected up to 0-20 cm from faecal pats, between the fungus-treated and control groups, and a 58% reduction when the sampling distance was 20-40 cm from faecal pats (P< 0.01). The treatment with sodium alginate pellets containing the nematode-trapping fungus M. thaumasium reduced trichostrongyles in tropical south-eastern Brazil and could be an effective tool for the biological control of this parasitic nematode in beef cattle. However, in such a tropical climate with low rainfall the fungal viability can be reduced.

Comparison between the action of nematode predatory fungi Duddingtonia flagrans and Monacrosporium thaumasium in the biological control of bovine gastrointestinal nematodiasis in tropical southeastern Brazil.

Sodium alginate pellets of the nematode predatory fungi Duddingtonia flagrans and Monacrosporium thaumasium were evaluated in the biological control of bovine gastrointestinal nematodiasis. Three groups (A-C) of ten six month old male Nelore bulls were kept in paddocks of Brachiaria decumbens for 12 months. Each animal of group A received 1g/10 kg of body weight (b.w.) of pellets of D. flagrans (0.2 g of fungus/10 kg b.w.) and of group B, 1g/10 kg of b.w. of pellets of M. thaumasium (0.2 g of fungus/10 kg b.w.), twice a week, for 12 months. Animals of the group control received no fungus. The monthly averages of egg count per gram of feces of the animals of groups A and B were 56.67% and 47.8% smaller, than the animals of group C (p<0.05), respectively. Treatment of bulls with pellets containing the nematophagous fungi D. flagrans and M. thaumasium can be used as an alternative treatment of bovine gastrointestinal nematodiasis, however, D. flagrans was more efficient than M. thaumasium for the biological control in the environmental conditions of the present study.

Anticoccidial efficacy of drinking water soluble diclazuril in the control of Eimeria acervulina oocysts on experimentally-infected broiler chickens / Eficiência do diclazuril (formulação líquida) no controle de oocistos de Eimeria acervulina em frangos de corte experimentalmente infectados

The experiment was carried out with 150 Cobb broiler chickens divided into 3 groups with 50 birds each. The groups of infected chickens orally received 1ml of inoculum containing 3x103 Eimeria acervulina sporulated oocysts at 12 days of age. Group 1 was kept as a positive control with infected non-medicated birds, group 2 was medicated with diclazuril (1%) with a dose of 1mL/4 L of drinking water for 2 successive days, 5 days after infection, while group 3 was kept as negative control with non-infected and non-medicated birds. Oocysts count per gram of feces, score of macroscopic intestinal lesions and weight gain were evaluated. The group treated with diclazuril showed significant and satisfactory improvement in the assessment criteria when compared to the infected non-medicated group. The results revealed more reduction in the total oocyst count and intestinal lesion score in the medicated than in the infected non-treated group. The results confirmed that (1%) liquid diclazuril is effective to control Eimeria infection.

O experimento foi realizado com 150 frangos de corte da linhagem Cobb, divididos em 3 grupos de 50 aves cada. Os frangos de dois grupos (G1 e G2) receberam, por via oral, 1mL de inóculo contendo 3x103 oocistos de Eimeria acervulina aos 12 dias de idade. O grupo 1 foi mantido como grupo controle positivo (infectado não medicado), o grupo 2 foi medicado com diclazuril (1%) na dose de 1mL/4 litros de água potável por dois dias sucessivos, cinco dias após a infecção. Um terceiro grupo (G3) foi mantido como controle negativo não infectado e não medicado. O número de oocistos por grama de fezes (OOPG), o escore de lesões macroscópicas intestinais e o ganho de peso corporal foram avaliados. No G1, o OOPG foi de 3,67x106 e o peso final foi de 1,392kg, valores significativamente diferentes do OOPG de 1,93x106 oocistos e do peso final de 1,613kg do G2 (diclazuril). Os resultados provaram que o diclazuril (1%) em formulação líquida e na dosagem de 1mL/4 litros de água por dois dias sucessivos foi eficaz no controle de Eimeria acervulina.

Biological control of trichostrongyles in beef cattle by the nematophagous fungus Duddingtonia flagrans in tropical southeastern Brazil.

The efficacy of a fungal formulation based on the nematophagous fungus Duddingtonia flagrans was assessed in the control of cattle trichostrongyles. Twenty male Nellore calves, six-month-old, divided in two groups (fungus-treated and control without fungus) were fed on a pasture of Brachiaria decumbens naturally infected with larvae of bovine trichostrongyles. Animals of the treated group received doses of sodium alginate mycelial pellets orally (1 g/10 kg live weight, twice a week), for 12 months. Feces samples were collected for egg count (eggs per gram of feces-EPG) and coprocultures during 12 months. There was a significant reduction in EPG (56.7%) and infective larvae (L3) in coprocultures (60.5%) for animals of the treated group in relation to the control group at the end of the study. There was a significant reduction of L3 (64.5%) in herbage samples collected up to 0-20 cm from fecal pats and 73.2% in distant samples (20-40 cm) between the fungus-treated group and the control group. The treatment with sodium alginate pellets containing the nematode trapping fungus D. flagrans reduced trichostrongylid in tropical southeastern Brazil and could be an effective tool for biological control of this parasitic nematode in beef cattle.

Histomorphometry and macroscopic intestinal lesions in broilers infected with Eimeria acervulina.

This study aimed at measuring intestinal villi and assessing the intestinal absorptive area in broilers infected with Eimeria acervulina under different treatments to control coccidiosis. The experiment was divided into two stages, carried out in successive housings, raised in the same environment (or aviary). In the first stage, on 25 May 2008, fifty 12-day-old birds were orally inoculated with 3 x 10(3) oocysts of E. acervulina. In the second stage, on July 2008, other 50 birds were allocated on litter contaminated by the feces of birds on the first housing (natural infection by oocysts present in the reused litter). The experiment was arranged in a complete randomized design with five treatments and three replicates of 10 chicks per treatment. Broiler chicks were housed at 1 day of age and autopsies were performed at 21 days of age. Three 2-cm-long segments of the duodenum were excised from each bird and fixed in 10% buffered formalin. A total of 30 slides were prepared for each treatment, totaling 150 evaluated histological sections using H&E staining. Villus morphology was carried out by the HL Image 97 software. The intestinal absorptive area was calculated and macroscopic lesions were classified according to standard lesion scores. Results showed that intestinal villus measurements and absorptive area are directly affected by E. acervulina and that there is direct and positive correlation between the macro and microscopic findings observed in intestinal coccidiosis. E. acervulina causes shortening of villi and reduction in the intestinal absorptive area, affecting broiler growth. The prevention method of litter fermentation during the interval between housings and oral administration of Diclazuril can reduce the severity of intestinal lesions by E. acervulina in broilers impairing oocyst virulence or viability.

Viabilidade de formulação peletizada do fungo nematófago Monacrosporium sinense, no controle biológico de nematóides parasitos gastrintestinais de bezerros / Viability of pellet formulation of Monacrosporium sinense as biological control of gastrointestinal nematodes of calves

A viabilidade de uma formulação do fungo Monacrosporium sinense foi avaliada no controle de nematóides parasitos gastrintestinais de bovinos. Dois grupos de 10 bezerros cada um, mestiços Holandês x Zebu, de seis a nove meses de idade, foram colocados em pastagem de Brachiaria brizantha. Em um dos grupos, cada animal recebeu 20g de péletes em matriz de alginato de sódio, contendo massa miceliana do fungo M. sinense via oral, duas vezes por semana, durante seis meses, com início no mês de outubro; no outro grupo, controle, os bezerros não receberam esse tratamento. As contagens de ovos por grama de fezes (OPG) e de larvas infectantes por kg de matéria seca foram maiores (P<0,05) no grupo-controle, e a diferença entre o OPG dos dois grupos, no final do experimento, foi de 79 por cento. A viabilidade dos péletes em germinar e a atividade predatória do fungo após o encapsulamento foram avaliadas in vitro. A porcentagem de péletes com cultivo positivo para o fungo variou entre 90 e 100 por cento, e o percentual de redução de larvas infectantes in vitro variou entre 90,6 e 100 por cento. A aplicação de péletes de M. sinense na dosagem e periodicidade usadas são eficazes no biocontrole de nematóides parasitos gastrintestinais de bovinos.

The viability of a formulation of the fungus Monacrosporium sinense was evaluated as control of bovine gastrointestinal nematodes parasites. Two groups were used and they were made up of 10 Holstein X Zebu crossbred, six to eight-month-old. They were grazing on Brachiaria brizantha pasture. In the treated group, each animal received orally, twice a week 20g of pellets of sodium alginate containing mycelial of the fungus M. sinense, during six months, with the onset in October. In the control group, the calves did not receive that treatment. The counting of eggs per gram of faeces (EPG) and the counting of infective larvae per kg of dry matter were higher (P<0.05) in the control group than in the treated group. The difference of the EPG between the groups at the end of the experimental period was 79 percent. The viability of the pellets germination and the predatory activity of the fungus after the encapsulation were evaluated in vitro. The percentage of pellets with positive culture for fungus varied between 90-100 percent and the percentage of reduction of infective larvae varied between 90.6-100 percent. The use of that dose and the periodic application of M. sinense pellets were efficient as control of bovine gastrointestinal nematode parasites.

Efeito antagônico de fungos predadores dos gêneros Monacrosporium, Arthrobotrys e Duddingtonia sobre larvas infectantes de Cooperia sp. e Oesophagostomum sp. / Antagonistic effect of nematophagous fungi Monacrosporium, Arthrobotrys and Duddingtonia on infective Cooperia sp. and Oesophagostomum sp. larvae

Seis isolados dos fungos nematófagos Monacrosporium thaumasium (isolado NF 34A), Monacrosporium sinense (isolado SF 470), Monacrosporium appendiculatum (isolado CGI), Arthrobotrys robusta (isolado I 31), Arthrobotrys cladodes (isolado CG 719) e Duddingtonia flagrans (isolado CG 768) foram avaliados em laboratório quanto à capacidade de predar larvas infectantes de Cooperia sp. e Oesophagostomum sp. Nos testes in vitro, os fungos foram eficientes em predar os nematóides (P<0,05), e não houve variação na capacidade predatória entre os fungos testados (P>0,05) durante os cinco dias do ensaio. Estruturas reprodutivas (conídios) foram encontradas em todos os isolados no quinto dia. Todos os fungos testados são promissores para serem utilizados no controle biológico de Cooperia sp. e Oesophagostomum sp., parasitos de bovinos.

Six isolates of nematophagous fungi Monacrosporium thaumasium (isolate NF 34A), Monacrosporium sinense (isolate SF 470), Monacrosporium appendiculatum (isolate CGI), Arthrobotrys robusta (isolate I 31), Arthrobotrys cladodes (isolate CG 719) and Duddingtonia flagrans (isolate CG 768) were evaluated under laboratory conditions regarding the capacity to entrap infective Cooperia sp. and Oesophagostomum sp. larvae. In the in vitro tests the fungi tested were equally efficient to prey the nematodes (P<0.05) during the five days of the experiment. Reproductive structures (conidia) from all isolates were visualized in 5th day. All fungal isolates were efficient in the control of bovine Cooperia sp. and Oesophagostomum sp. parasites.

Controle biológico de tricostrongilídeos (Nematoda: Trichostrongyloidea) gastrintestinais de bovinos pelo fungo Monacrosporium sinense / Biological control of gastrointestinal trichostrongylids (Nematoda: Trichostrongyloidea) of cattle by pellets of Monacrosporium sinense

Avaliou-se a resistência do fungo nematófago Monacrosporium sinense (isolado SF 470) em passar pelo trato gastrintestinal de bovinos e testou-se sua capacidade predatória sobre larvas infectantes de tricostrongilídeos após a passagem. Cem gramas de péletes formulados em matriz de alginato de sódio do isolado fúngico de M. sinense foram administrados, por via oral (VO), a dois bezerros mestiços holandês zebu de seis meses de idade. Para o controle utilizaram-se dois outros animais, de igual padrão, aos quais foram administrados 100g de péletes, VO, livre do isolado fúngico. Amostras fecais, coletadas nos tempos de 12h, 18h, 24h, 48h, 72h e 96h após os tratamentos, foram acondicionadas em placas de Petri e em coproculturas a 25ºC por 15 dias. Houve redução (P<0,05) no número de larvas infectantes de Cooperia spp. e Haemonchus spp. nos animais tratados em relação ao grupo-controle. A diferença ao final do experimento foi de 69,9 por cento nas placas e 61,3 por cento nas coproculturas. O fungo M. sinense demonstrou ser efetivo no controle de larvas infectantes de Cooperia spp e Haemonchus spp em condições de laboratório.

Aplicação de formulação do fungo predador de nematóides Monacrosporium thaumasium (Drechsler, 1937) no controle de nematóides de bovinos / Control of bovine gastrointestinal nematodes using formulation of the nematode-trapping fungus Monacrosporium thaumasium (Drechsler, 1937)

A viabilidade de uma formulação do fungo Monacrosporium thaumasium (Drechsler, 1937) foi avaliada no controle biológico de nematóides parasitos gastrintestinais de bovinos. Dois grupos de sete bezerras cada, mestiças Holandês x Zebu, de quatro a seis meses de idade, foram colocados em pastagens de Cynodon dactilon. No grupo A, cada animal recebeu 20g de pellets (formulação granulada) de M. thaumasium via oral, duas vezes por semana, durante quatro meses, com início na estação chuvosa (outubro, 2001). No grupo B (controle), as bezerras não receberam nenhum tratamento. As contagens de ovos por grama de fezes (OPG) e das larvas infectantes encontradas na pastagem do grupo B foram significativamente maiores (P<0,05) do que as do grupo A e a diferença entre o OPG dos animais dos grupos A e B, no final do experimento, foi de 88,8 por cento. O gênero Cooperia foi o mais prevalente em ambas as pastagens. Conclui-se que a aplicação de pellets de M. thaumasium na dosagem e periodicidade de aplicação usadas foi eficiente no controle de nematóides parasitos gastrintestinais de bovinos.