Sustainable control of gastro-intestinal nematodes in organic and grass-fed small ruminant production systems
The purpose of this project is to develop and validate integrated strategies for control of parasitic nematodes in organic small ruminant production in warm humid climates. Organic forage production is achievable, but low weight gains on grass-dominant pastures and infection with gastrointestinal nematodes (GIN) leading to reduced productivity and death losses, particularly of lambs and kids, are major constraints to profitable small ruminant production. As there is no ‘silver bullet’ to solve the problem of GIN infection in small ruminants, combinations of the FAMACHA system, copper oxide wire particles, rotational grazing, use of nutrient-rich and condensed tannin-rich forages will be tested at university, USDA, and on-farm sites in the proposed program, with results disseminated to clientele groups through producer workshops, scientific and producer-oriented publications, project web site (SCSRPC.org), and various institutional print and web-based extension publications. Studies are in progress.
1. Examine the use of sericea lespedeza and other condensed tannin-containing plants, as fresh or dried forage (hay, pellets), for gastrointestinal nematode control in sheep and goats.
2. Examine alternative forage systems for organic and grass-fed small ruminants to decrease gastrointestinal nematode infection and increase weight gains.
3. Test integrated, forage-based gastrointestinal nematode control systems for organic and grass-fed small ruminant production on-farm.
4. Complete impact assessment of non-chemical gastrointestinal nematode control techniques on small ruminant producers.
- Organic forages have been established and grazing studies will be conducted.
Preliminary results of kids and lambs grazing organically established cowpeas and soybeans, but not pearl millet were positive, but replication is necessary.
On-farm inclusion of chicory in a rotational grazing system for Katahdin lambs and multi-species grazing with cattle were positive and this study will be replicated.
Use of copper oxide wire particles at the time of lambing/kidding appears to inhibit the peri-parturient rise in ewes/does (this study is being prepared for publication).
Desmodium paniculatum (panicled tick-clover) was established at Stephenville, TX during the 2008 growing season. These were irrigated due to a generalized drought but sufficient number of plants survived to produce adequate hay in 2009. Additional data has been published on the productivity, nutritive value and condensed tannin concentrations of this native herbaceous legume.
Forage samples are being screened for high concentrations of condensed tannins that are preferred by sheep or goats from various locations in the southeastern USA and U.S. territories, including Texas, Louisiana, Georgia, St. Croix and Puerto Rico. These are being analyzed not only for condensed tannin assays, but for general nutritive values including nitrogen, fiber, and in vitro rumen disappearance.
Impacts and Contributions/Outcomes
It is too early to realize impacts in the early stage of this project.