Sustainable Control of Gastro-intestinal Nematodes in Small Ruminants

Sustainable Control of Gastro-intestinal Nematodes in Small Ruminants

Summary

Use of sun-dried forage of the condensed tannin (CT)-containing legume sericea lespedeza (SL) to control gastrointestinal nematodes in sheep and goats was evaluated in two feeding trials. In the goat trial, SL hay at 50 and 75% of daily intake significantly reduced fecal egg counts, and similar results were observed with sheep fed at 75% of daily intake. The CT content was determined for a number of other temperate and subtropical forages with anthelmintic potential. SL for grazing trials was established on-farm in Georgia and Alabama. A number of Smart Drenching and FAMACHA producer workshops were completed in 2005 as part of this project.

Objectives/Performance Targets

1. Increase level of adoption of available sustainable GIN control strategies in the southeastern USA and PR by disseminating state-of-the-art knowledge and procedures, plus conduct cost-benefit analyses of these systems.
2. Investigate use of existing and developing novel non-chemical approaches for controlling GIN in small ruminants.
3. Develop and test sustainable small ruminant parasite control systems integrating conventional and novel GIN control strategies.

Accomplishments/Milestones

Two feeding trials with sheep and goats given sericea lespedeza (SL) hay to control gastrointestinal nematode infection were completed at Louisiana State University, Baton Rouge, LA, and Fort Valley State University, Fort Valley, GA, respectively. Both trials were successful, with significantly reduced fecal egg counts and increased blood packed cell volume in animals given ground SL compared with ground bermudagrass. A sheep grazing trial with SL was initiated in South Africa by our collaborators at the Onderstepoorte Veterinary Institute, Onderstepoorte, SA. Ground SL hay was successfully pelleted at a feed mill in TX. Collection of additional condensed tannin (CT)-containing forages for analysis of CT content and in vitro testing of anthelmintic activity was initiated in several states and Puerto Rico. SL pastures for on-farm grazing trials was established in Georgia and Alabama. Smart Drenching and FAMACHA producer workshops were held in AR, LA, TX, NC, OK, and PR, with announcements for workshops posted on our Contortium web site (SCSRPC.org).

Studies planned for 2006 include continuation of the SL grazing trial in South Africa, a dose titration trial with parasitized lambs given different levels of pelleted SL, and two goat trials with SL meal, including a growth study with recently-weaned kids and a grazing trial with SL meal fed as a supplement to parasitized kids on pasture. CT forage samples will continue to be collected and analyzed for total CT content and in vitro anthelmintic activity. Several producer workshops will be conducted during the second year of the project for training in use of FAMACHA and to present information on establishment and management of sericea lespedeza.

Impacts and Contributions/Outcomes

This work has generated interest in use of sericea lespedeza for controlling gastrointestinal nematodes in sheep and goats. The number of producers calling Consortium members for information on establishment and management of this crop greatly increased in 2005. In addition, the number of hits on our Consortium web site has been growing steadily each month. Since it was started in June 2004, the web site has been visited over 28,000 times.

Collaborators: