
There is a subset of tannins called condensed tannins, and some of the members of this group do seem to have beneficial effects against worms. In the U.S., Sericea lespedeza is one of the forages containing condensed tannins that has potenial for use in parasite control.
Members of the Southern Consortium for Small Ruminant Parasite Control (SCSRPC) are currently investigating how sericea can be used in integrated parasite control programs.
Source: SCSRPC web site. Submitted by Dr. Anne Zajac, DVM, PhD, Virginia-Maryland Regional College of Veterinary Medicine.
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