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ARS Home » Southeast Area » Booneville, Arkansas » Dale Bumpers Small Farms Research Center » Research » Research Project #431847

Research Project: Understanding Parasite Resistance in Organic Livestock and Using a Systems Approach for Control

Location: Dale Bumpers Small Farms Research Center

Project Number: 6020-21310-011-03-I
Project Type: Interagency Reimbursable Agreement

Start Date: Sep 1, 2016
End Date: Aug 31, 2021

1. Determine mechanism of action of resistance/resilience to gastrointestinal nematodes (GIN). 2. Identification of genetic loci associated with resistance to GIN. 3. Examine farm systems that minimize the need for deworming. 4. Work with the farmers through extension and the National Sheep Improvement Program to obtain estimated breeding values (EBVs) on parasite resistance.

To understand parasite resistance in organic livestock, sheep will be used throughout the project. A key challenge in livestock industries is predicting genetic predisposition for disease susceptibility such as gastrointestinal nematodes (GIN) infection, a difficult-to-measure trait that may be one of the largest barriers to organic production and remains a challenge in the small ruminant industry. Through gene expression studies, we will find genes and gene pathways contributing to parasite resistance in Katahdin sheep. We will improve use of genetic information to improve the diversity and resilience of our production system. We will determine the immune response differences generated to different life stages of Haemonchus contortus (barber pole worm; the most economically devastating worm to small ruminants across the world), and determine the impact of Texel sires, which may have parasite resilience, as a terminal sire in Katahdin breeding on GIN infection, immune response to GIN, and production of offspring. We will use a systems approach to examine past successes for control of GIN (use of fall lambing to minimize need for deworming; use of forage species such as legumes or native lespedezas or other forages to aid in the control of GIN), continuing to collect data on fecal egg counts to incorporate into estimated breeding values at ARS and on several farms throughout the U.S. to collect phenotypes on parasite resistance. Integrating students, stakeholders and scientists, we will establish an infrastructure for transformational science, positively impacting rural economic development and prosperity.