Influence of weather and time of deposition on sheep faeces colonization by nematophagous fungi in the Mata region of Minas Gerais State, Brazil

The influence of climate and time of deposition on the colonization of sheep faeces by nematophagous fungi was examined in the Mata Region of Minas Gerais State, Brazil. Sheep faeces were collected from the rectums of animals and deposited on pastures of Brachiaria decumbens in the months of July and October 1995 and January and April 1996. Samples of the deposited faeces were recovered 3, 7 and 14 days after deposition. Sub-samples of faeces (2 g) were placed in the centre of a 2% water–agar petri dish. Free-living nematodes were added as bait, the plates incubated at room temperature and examined for 3 weeks. Isolated fungi were further cultured on corn-meal agar plates for identification. A total of 123 fungi was isolated from the 120 sheep faecal samples deposited on pastures including 22 in July, 39 in October, 41 in January and 21 in April. More than one-third of the fungi were recovered on the third day after deposition. Arthrobotrys oligospora and Monacrosporium eudermatum, were the most common predatory fungi and Harposporium anguillulae the most common endoparasite. Results showed that sheep faeces deposited on pastures of B. decumbens are colonized rapidly by a variety of nematophagous fungi and seasonality affects colonization. ©2000 Elsevier Science B.V. All rights reserved.