In vitro predatory activity of nematophagous fungi isolated from water buffalo feces and from soil in the Mexican southeastern.

Nematophagous fungi from the feces of water buffalo and soil from southeastern Mexico were isolated, and their in vitro predatory activity against Haemonchus contortus infective larvae (L3) (HcL3) was assessed. The fungi were isolated by sprinkling soil or feces on water agar plates. Six series of 10 Petri dishes containing a 7-day-old culture of each fungus and a series without fungi as the control were prepared. Five hundred HcL3 were added to each plate. The plates were incubated at room temperature. The average of recovered HcL3 was considered to estimate the larval reduction rate. Four nematophagous fungi isolates corresponding to Arthrobotrys oligospora, var microspora (strains 4-276, 269 and 50-80) and one identified as A. oligospora,var. oligospora (isolates 48-80) were obtained from water buffalo feces. From the soil, five isolates were isolated; three corresponded to A. musiformis (Bajío, Yumca and Macuspana isolates), and two isolates were identified as A. oligospora (Comalcalco and Jalapa de Méndez isolates). The predatory activity of isolates from water buffalo feces ranged between 85.9 and 100%. Meanwhile, the fungi from the soil ranged between 55.5 and 100% (p≤0.05). The nematophagous fungi obtained could have important implications in the control of parasites of importance in the livestock industry.