Nematophagous fungi as a biological control agent for nematode parasites of small ruminants in Malaysia: a special emphasis on Duddingtonia flagrans

Abstract

-Approximately 2 800 fresh dung samples from animals, mainly ruminant livestock, were screened for the presence of nematophagous fungi in Malaysia. Arthrobotrys spp. was noted on numerous occasions, but only one isolate of Duddingtonia flagrans was made. For the purposes of producing sufficient quantities of this fungus for feeding trials in sheep, various, commonly available, cheap plant materials were tested as possible growth substrates. This showed that cereal grains (wheat, millet and rice) were the best media for fungal growth. Pen feeding trials were carried out using sheep, both naturally and experimentally infected with nematode parasites (predominantely Haemonchus contortus), to test the efficiency of D. flagrans when administered either in a grain supplement, or incorporated into a feed block. These showed that the fungus survived gut passage in sheep and that dose rates of approximately 1× 10 6 D. flagrans spores / animal / day, reduced the percentage of infective larvae developing in faecal cultures by more than 90%. These results indicate that using D. flagrans as a biological control agent of nematode parasites, is a promising alternative to nematode parasite control of small ruminants in Malaysia, where anthelmintic resistance is now a major problem. Résumé -Les champignons nématophages comme agents de contrôle des nématodes des petits ruminants en Malaisie : l'exemple de Duddingtonia flagrans. La présence de champignons néma-tophages a été recherchée dans environ 2 800 échantillons de fèces d'animaux, provenant principalement de troupeaux de ruminants, en Malaisie. Arthrobotrys spp. a été trouvé à de nombreuses occasions, mais seul un isolat de Duddingtonia flagrans a été détecté. Afin de produire des quantités suffisantes de ce champignon pour des tests dans l'alimentation du mouton, plusieurs plantes facilement disponibles et bon marché ont été testées en tant que substrat de croissance. Ces essais ont montré que les grains de céréales (blé, millet et riz) constituaient le meilleur milieu pour la croissance des champignons. Des essais alimentaires en enclos ont été menés en utilisant des moutons infestés naturellement ou expérimentalement par les nématodes parasites (principalement Haemonchus contortus), afin de tester l'efficacité de D. flagrans administré soit dans un supplément de grains, soit incorporé dans un bloc de nourriture. Les résultats ont montré que le champignon survivait au passage dans les intestins de mouton et que des doses d'environ 10 6 spores de D. flagrans par animal et par jour réduisaient de plus de 90 % le pourcentage de larves infectieuses se développant dans les cultures fécales. Ces résultats montrent que le principe de l'utilisation D. flagrans comme agent biologique de contrôle des nématodes parasites des petits ruminants est une alternative prometteuse en Malaisie, où la résistance aux anthelmintiques est aujourd'hui un problème majeur.parasite nématode / ruminant / tropique / contrôle biologique

Resistance of different fungal structures of Duddingtonia flagrans to the digestive process and predatory ability on larvae of Haemonchus contortus and Strongyloides papillosus in goat feces

“…flagrans showed higher predatory activity on S. papillosus. Experiments with other D. flagrans isolates had already demonstrated the high predatory effectiveness of this species on H. contortus L 3 (Mendoza- Chandrawathani et al 2002).…”

Biological control of sheep gastrointestinal nematodiasis in a tropical region of the southeast of Brazil with the nematode predatory fungi Duddingtonia flagrans and Monacrosporium thaumasium

“…In Malaysia, Chandrawathani et al (2002) observed the effectiveness of the treatment with the fungus D. flagrans, daily administered to ovine. On the other hand, Terril et al (2004), using this same fungus, found a The number of (L 3 ) recovered from the paddocks in the distances of up to 20 cm from the fecal mass and 20-40 cm far from the fecal mass was similar (p>0.05) for the animals in groups 1, 2, and 3 in the months when the experiment took place.…”

Screening of different sample types associated with sheep and cattle for the presence of nematophagous fungi in China

“…D. flagrans were noted in 13 feces, 10 dung compost and 1 pasture soil samples, and 11 pure isolates were recovered. Detection of D. flagrans in China, following its isolation in continental Europe , Australia , North and South American continents , South Africa , and Malaysia and India in Asia, provides further support that this fungus is distributed worldwide. These findings also provide the opportunity to compare local fungi with strains from other locations regarding their efficacy in reducing infective parasitic larvae on pastures.…”