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<OL> <LI> Determine effectiveness as a dewormer and palatability of sericea lespedeza leaf meal from first, second and third cutting incorporated into a 16% crude protein pellet for kids and lambs. Because the sericea lespedeza pellets are made from leaf meal and balanced for crude protein, it is expected that palatability will be similar among cuttings and may be similar to the bermudagrass pellet because all include molasses to enhance palatability. It is expected that the pelleted diet will control parasites to a greater extent than the control diet. <LI> Determine whether the sericea lespedeza leaf meal pelleted diet would decrease growth of pathogens in the gut of slaughter lambs. . It is expected that inclusion of the condensed tannins from the sericea lespedeza pellet will reduce fecal shedding and carcass contamination of E. coli.
NON-TECHNICAL SUMMARY: Internal parasites are the greatest health and production challenge for sheep and goats in southeastern states and others during warm, humid conditions (including Northeastern, Midwestern and irrigated pastures in Western US). Haemonchus contortus or barber pole worm thrives in warm, humid climates and is a voracious blood feeder that can cause anemia and death to the animal if left untreated. Dewormer resistance has left many producers without any chemical control of worms, which was heavily relied on in the past. Published studies reported that consumption of sericea lespedeza (or Chinese bush clover), a condensed tannin rich forage, has offered control of parasites in sheep and goats. Feeding of condensed tannins may reduce gut pathogens, which would lead to safer meat products. The objectives of this project are to determine the effectiveness of a sericea lespedeza pellet processed by the Sims Brothers, Inc. as an aid in controlling internal parasites in lambs and goat kids and the effect on food safety in lambs. To examine the effect of the pelleted sericea lespedeza on controlling worms, lambs and kids will be fed a proprietary sericea lespedeza pellet or a comparable bermudagrass based pellet as a control from weaning until market weight. Measures of worm infection and growth of the animals will be measured throughout the study. The number of times an animal required deworming (selective deworming based on anemia will be used) will be recorded and economics will be considered. The second study will determine whether bacteria in the gut can be reduced by feeding the sericea lespedeza pellets compared to the bermudagrass control to lambs. Level of bacteria in the feces will be measured. Lambs will be slaughtered seven days after oral introduction of the bacteria and gut contents and tissues will be collected to determine food safety. If successful, this project has the potential to increase sustainability and profitability of sheep and goat producers that have no effective chemical dewormers and provide a product for feedlots or pre-slaughter animals to decrease harmful bacteria on the processed carcass increasing food safety of meat products.
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APPROACH: Objective 1. The objective is to determine palatability of sericea leaf meal pellets from first, second, third cutting (may only get two cuttings if weather conditions not good; i.e., too much or too little rainfall) and effectiveness at controlling worms in lambs and kids from weaning until animals reach market weight. At the USDA Agricultural Research Service in Booneville, AR, weaned meat goat kids and lambs naturally infected with nematode parasites will graze grass pastures post-weaning (90 to 120 days of age; starting May/June 2010) and receive 2% of body weight per day of a 16% crude protein (dry matter basis) pellet containing 75% bermudagrass (control) or sericea lespedeza (Sims Brothers manufactured pellets from at least two different cuttings) hay and remaining ingredients (corn, soybean, molasses) to balance crude protein (n = 16/treatment on 2 reps or 4 plots per species). Amount of feed refused, if any, will be determined. Animals will be dewormed for anemia based on a packed cell volume ¡Ü 16% on an individual basis as needed. Fecal egg counts and blood packed cell volume will be determined weekly for 12 weeks, along with number of deworming/treatment by the end of the study. Body weights will be determined every 4 weeks. Fecal egg counts will be measured using modified McMaster's technique. Feces will be cultured for recovery of larvae and proportion of Haemonchus contortus.<P>
Objective 2. The objective is to determine whether E. coli shedding and infection in the gut of lambs can be reduced by feeding sericea lespedeza leaf meal before slaughter. Market weight lambs (n = 20) will be transported from USDA, ARS in Booneville, AR to Fort Valley State University facilities. Lambs will be housed indoors and acclimated to a diet of 16% alfalfa pellets (control) or the 16% sericea lespedeza leaf meal pellets (n = 10/treatment) at 3.5% body weight for seven days. Lambs then will be individually inoculated with 10 ml of tryptic soy broth containing E. coli O157:H7. Fecal samples will be collected daily for seven days to determine fecal shedding of pathogens. Lambs will be slaughtered seven days after E. coli inoculation and intestinal contents and tissues from ileum, cecum, and rectum will be collected for quantification of E. coli. Bacterial culture and enumeration will be determined. Data for both studies will be analyzed using SAS (1996) using a mixed procedures program with repeated measures for FEC, PCV, body weight and fecal shedding collected over time. <P>
Data will be analyzed by Dr. Burke and interpretations will be included in a technical and producer-friendly manuscript for dissemination. The project will be evaluated by other scientists and veterinarians in the Southern Consortium for Small Ruminant Parasite Control (www.scsrpc.org). There has been a large demand from sheep, goat, llama, and alpaca producers for pelleted sericea lespedeza. This project is expected to have a large impact on these producers that are searching for methods to control internal parasites in their animals.