In vitro stress selection of nematophagous fungi for biocontrol of parasitic nematodes in ruminants

Journal of Helminthology - Tập 65 Số 3 - Trang 193-200 - 1991
M. Larsen1, J. Wolstrup, S A Henriksen, Carin Dackman, J. Grønvold, P. Nansen
1Department of Veterinary Microbiology, Royal Veterinary and Agricultural University, Bülowsvej, Frederiksberg, Denmark.

Tóm tắt

ABSTRACT

Laboratory experiments were designed to select nematophagous fungi that were able to survive in vitro conditions simulating passage through the gastro-intestinal tract of cattle. All of the tests were conducted at 39°C. In a primary stress selection step in diluted rumen fluid, 21 isolates were obtained. Each of the primary stress selected isolates was tested in synthetic saliva, rumen fluid simulating the activity in the rumen, rumen fluid followed by pepsin-hydrochloric acid treatment simulating the additional effect of ruminal and abomasal activity, pepsin-hydrochloric acid solution simulating conditions in the abomasum and finally in a trypsin solution as an example of enzyme activity in the gut. The effect of the rumen fluid alone, or rumen fluid followed by pepsin-hydrochloric acid treatment, were responsible for the reduction in surviving fungal isolates. Only six of thirteen isolates belonging to the genus Arthrobotrys survived while seven of eight isolates of the genus Duddingtonia survived. Fourteen isolates were tested for their predatory capacity in a dung pat bioassay. Fungi of the genera Arthrobotrys and Duddingtonia reduced the development of Ostertagia ostertagi third stage larvae by approximately 75% and 96% respectively compared to the number of larvae that developed from fungus-free control pats.

Từ khóa


Tài liệu tham khảo

10.1042/bj0430099

Nordbring-Hertz, 1972, Scanning electron microscopy of the nematode-trapping fungus Arthrobotrys oligospora, Scanning electron microscopy of the nematode-trapping fungus Arthrobotrys oligospora, 26, 279

Domsch, 1980, Compendium of Soil Fungi, 59

Schenck, 1977, A new nematode-trapping hyphomycete and a re-evaluation of Dactylaria and Arthrobotrys, A new nematode-trapping hyphomycete and a re-evaluation of Dactylaria and Arthrobotrys, 55, 977

10.1163/187529277X00372

Grønvold, 1987, Field experiments on the ability of Arthrobotrys oligospora (Hyphomycetales) to reduce the number of larvae of Cooperia oncophora (Trichostrongylidae) in cow pats and surrounding grass, Field experiments on the ability of Arthrobotrys oligospora (Hyphomycetales) to reduce the number of larvae of Cooperia oncophora (Trichostrongylidae) in cow pats and surrounding grass, 61, 65

Cooke, 1964, A key to the nematode-destroying fungi, A key to the nematode-destroying fungi, 47, 61

Van Oorschot, 1985, Taxonomy of the Dactylaria complex, V. A review of Arthrobotrys and allied genera, Studies in Mycology, 26, 61

Barron, 1977, The nematode-destroying fungi. Topics in Mycobiology

Dackman, 1987, Quantification of predatory and endoparasitic nematophagous fungi in soil, Quantification of predatory and endoparasitic nematophagous fungi in soil, 3, 89

10.1017/S0022149X00011676

Hvelplund, 1974, Growth of cellulolytic bacteria in the in-vitro fermentation tube. Den kgl. Veteriœrog Landbohøjskole, Årsskrift, 1974, 101

Grønvold, 1989, Attempts to control infection with Ostertagia ostertagi (Trichostrongylidae) in grazing calves by adding mycelium of the nematode-trapping fungus Arthrobotrys oligospora (Hyphomycetales) to cow pats, Attempts to control infection with Ostertagia ostertagi (Trichostrongylidae) in grazing calves by adding mycelium of the nematode-trapping fungus Arthrobotrys oligospora (Hyphomycetales) to cow pats, 63, 115

Haard, 1968, Taxonomic studies on the genus Arthrobotrys Corda, Taxonomic studies on the genus Arthrobotrys Corda, 60, 1140

Tilley, 1963, A two-stage technique for the in vitro digestion of forage crops, A two-stage technique for the in vitro digestion of forage crops, 18, 104

Jarowaja, 1970, Rodzaj Arthrobotrys Corda (The genus Arthrobotrys Corda), Rodzaj Arthrobotrys Corda (The genus Arthrobotrys Corda), 6, 337