Timely topic: December 2014
Sericea lespedeza: "wise man's alfalfa"
By Dr. Tom Terrill
Associate Professor of Animal Science
Fort Valley State University
Because of its ability to tolerate infertile, acidic soils and grow well on sloping land with minimal lime and fertilizer inputs, the perennial warm-season legume sericea lespedeza (SL; Lespedeza cuneata) has earned the nickname "Poor man’s alfalfa." With recent research on the potential health and environmental benefits of including SL in the diet of ruminant animals, it may be time for a new nickname.
Like other forages that contain condensed tannins (CT), a compound that binds to protein when the plant is chewed and digested, SL is non-bloating. It also lowers the production of methane from the animal’s rumen, reducing the contribution of this powerful greenhouse gas to global warming.
However, for farmers trying to keep their livestock healthy during a period when anthelmintic drugs are rapidly losing their effectiveness, the excellent anti-parasitic properties of SL in fresh (grazed) or dried (hay, leaf meal, pellets) forms in the diet of sheep, goats, and other ruminants may be most important.
Research by ACSRPC members over the past few years has demonstrated the effectiveness of SL against internal parasites, particularly Haemonchus contortus, the infamous blood-sucking "barber pole worm" and Eimeria spp., a protozoan parasite that causes coccidiosis, which can be a devastating disease in kids and lambs during times of stress, such as at weaning.
In preparation for next year’s peak parasite season (April to October), producers should start thinking now about when and how to plant SL to attain a successful stand. Planting of hulled, certified SL seed should be done in the spring when the danger of a killing frost has passed. Because it is a small seed, SL should not be planted deeper than ¼ in., on a well-prepared, firm seedbed. Seeding rates and additional information on SL establishment can be found under the Parasite Control/Sericea lespedeza dropdown menus on this web site.
Information on feeding SL pellets for parasite control was provided recently in response to a producer’s question:
“Currently, we recommend feeding pellets at 50% or more (make sure nutrient needs are met by providing supplemental protein or energy if needed) of the diet for parasite control. For the control of coccidia, it is best to start feeding in anticipation of a stressful event that might cause coccidiosis. For example, about two weeks before weaning, offer the pellets (it may be slow at first, but it should pick up, depending on other feeds available). Then feed for an additional 4 to 6 weeks after weaning.
For barberpole worm, you might also take the same approach. Feed for about an 8-week period during the worst of the worm exposure, which again, might be around weaning time. We don’t necessarily recommend feeding for longer than 8 weeks because in some locations/farms, the condensed tannins in the SL may bind important trace minerals, and may slow weight gain. It’s best to offer a good quality trace mineral along with the SL pellets.
For barberpole control, once you remove the pellets, you may need to pay close attention to the animals because sometimes, the animal becomes more susceptible after SL removal, especially if worm conditions are still very good. You may want to dose with 0.5 g copper oxide wire particles at time of withdrawal”.
Joan Burke, USDA/ARS in Booneville, Arkansas
Information on a commercial source of "AUGrazer" SL seeds and leaf meal pellets is available at the following website: simsbrothers.com.
Although we still don’t know the exact anti-parasitic mechanism of SL in the diet of animals, research is starting to give us some clues. For instance, the chemical structure of SL tannins is unique compared with other types of CT, consisting of very large polymers of nearly pure "prodelphinidin-type" tannins, which are very reactive with protein, possibly including those on the surface of adult parasites.
Although there are still questions to be answered about this plant, as a low-input, non-bloating forage for natural control of internal parasites, it may be time to change its nickname from "Poor man’s alfalfa" to 'Wise man’s alfalfa".