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.

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.

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.

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.

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.