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ARS Home » Southeast Area » Booneville, Arkansas » Dale Bumpers Small Farms Research Center » Research » Publications at this Location » Publication #409326
Research Project: Sustainable Small Farm and Organic Grass and Forage Production Systems for Livestock and Agroforestry

Location: Dale Bumpers Small Farms Research Center

Title: Determining in vivo and in vitro predatory activity of Duddingtonia flagrans and interaction with dietary coccidiostat

Author
item Burke, Joan
item PETERSSON, KATHERINE - University Of Rhode Island
item KASS, ELIZABETH - University Of Rhode Island
item VATTA, ADRIANO - Louisiana State University
item MILLER, JAMES - Louisiana State University
item Rohila, Suman

Submitted to: American Society of Animal Science Southern Section Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 11/30/2023
Publication Date: 8/1/2024
Citation: Burke, J.M., Petersson, K., Kass, E., Vatta, A., Miller, J., Rohila, S. 2024. Determining in vivo and in vitro predatory activity of Duddingtonia flagrans and interaction with dietary coccidiostat. American Society of Animal Science Southern Section Meeting. https://doi.org/10.1093/jas/skae019.103.
DOI: https://doi.org/10.1093/jas/skae019.103

Interpretive Summary:

Technical Abstract: A nematode trapping fungus, Duddingtonia flagrans (Df), fed to sheep is useful for biocontrol gastrointestinal nematodes on pasture. The objectives were to validate methods to determine viability of a commercial source of D. flagrans before beginning research studies, and second, examine the interaction between Df and dietary coccidiostat. In Jan 2023, weaned Katahdin lambs (97.3 ± 1.2 d of age; 19.5 ± 1.3 kg BW; moderately anemic with a packed cell volume of 26.5 ± 1.4 %), naturally infected with predominantly Haemonchus contortus (89%) and mean fecal egg count (FEC) of 6860 eggs/g, were randomly assigned to: no Df (CON) or 1.5 g BioWorma®/d in three gel capsules (DF; 5 pairs/treatment). Fecal samples of 8 g/pair of lambs were collected and cultured on d 0, 2, 3, and 4 for 12 d at 25°C then baermannized to determine L3 recovery [(# L3/FEC)×100]. In a second study, conducted August 2023, 7 mo old anthelmintic-treated ram lambs (FEC < 500 egg/s) were fed supplement daily with coccidiostat (+C) or without (-C; n = 3/diet) on d -7 to 1, and, within diet, administered 3 g BioWorma®/d in 6 gel capsules (+DF; n = 2/diet) or not (-DF; n = 1) on d -1 and -2. Fecal samples were collected on d 0 (2 g/plate + 300 L3 of H. contortus) and d 1 (6 g/plate + 1000 L3) and placed on water agar plates (n = 3/lamb) at 25°C. Trapping structures were visually assessed after 24, 48, and 144 h, and cultures baermannized on d 7 and 8, respectively for L3 recovery. Data for variables collected one time were analyzed by Proc GLM (SAS) and for those collected serially, a Proc mixed with repeated measures was used. A 2×2 factorial was used in second study. As expected, there was a reduced L3 recovery (P = 0.005) in DF lambs in the first study. For the d 0 plates, DF formed loops and traps around L3 by d 6 and reduced L3 recovery (P < 0.001) without an effect (P = 0.38) or interaction (P > 0.05) by coccidiostat. For the d 1 coproculture, feces from one +DF-C ram appeared to have non-H. contortus L3 (which will be confirmed) and was removed from analyses. However, +C-DF reduced L3 recovery (P = 0.003) but did not antagonize DF. This aspect of the study will be repeated with additional reps, though it seems clear that Deccox can be added to the diet in the presence of BioWorma°. The in vitro studies allow detection of adverse issues with viability of Df and can reduce the number of animals needed for research studies.