Use of Herbs as De-wormers for Sustainable and Profitable Production of Sheep and Goats Under Natural Grazing Conditions
This project will help increase awareness of researchers and hair and wool sheep and meat goat producers alike on the potential of raising natural herbs as a low cost substitute for synthetic chemical dewormers on the deadly killer of these animals in the hot summer months due to internal parasites.
The three groups of chemical dewormers; benzimidazoles, avermectin, milbemycins and pyrantel are very costly and are increasingly less effective as a result of development of resistance by the internal parasites reported in the literature in recent years.
In this project, wormwood, (Artemesia absinthium) plants were grown in the greenhouse, cut and dried and fed to sheep and goats from June through September, and compared to the results from Ivomec (a commercial dewormer), a control, and a commercial combination of natural herbs.
The fecal egg counts, hematocrits, FAMACHA ® and weights were compared in the groups from June through September. Fecal egg counts in the sheep and goats were near zero in the wormwood group fed plants grown in the green house compared to the control, commercial dewormer and commercial natural herbs with a significant difference when statistically analyzed by SAS.
1. The three species of Artemesia, family Asteraceae, with known anthelmintic activity, have been selected for evaluation in this study. These are Artemesia herba alba (Morroccan mugwort), Artemisia absinthium (wormwood), and Artemesia afra (African wormwood). Several other herb species were considered before selecting these three. These are: Artemisia annua (sweet wormwood, sweet annie), Artemisia cina (santonica), Artemisia vulgaris (mugwort), Artemisia ludoviciana (western mugwort, white sage), Artemisia dracunculus (tarragon), and Artemisia brevifolia (seski). The vegetative or floral parts of A. cina, A. afra, A. dracunculus, A. absinthium, A. brevifolia, A. herba alba and A. vulgaris, were reported to have anthelmintic effects. However, no anthelmintic effect has been demonstrated for A. annua, and A. lucoviciana. The major criterion in the selection of the three species of Artemisia is current information about their demonstrated anthelmintic activity in the public domain. The other consideration in the selection is availability of the species in botanical collections in the United States.
The three herbs selected for this study can be grown at Lincoln University under greenhouse conditions (21-25 Degrees C ambient temperature and 70/90% day/night humidity) throughout the duration of the project to ensure a continuous source of high quality and clean plant material. Subsequently, the selected species will be propagated vegetatively to maintain true-to-type plant material. Plants will be grown to maturity to well-drained organic potting medium, and maintained at uniform growth rate by regular irrigation and balanced mineral nutrient supply.
The herbs will be delivered to the animals as crude powders. The powders will be prepared by grinding dried whole leaves of the herbs until a flowing powder is obtained. The choice of crude powder delivered is based on literature comparisons and preliminary studies carried out at Lincoln University’s Carver Farm. Literature comparisons show that higher parasite elimination efficiencies were achieved using this delivery approach as opposed to either aqueous or organic solvent extracts. The ground herbs will be added to the grain mixture at pre-determined dosages related to animal body weights, and fed to the animals. The only exception is for experiment on sustainability in which the herbs are grazed with conventional grazing plants by sheep and goats.
2. ANIMAL BREEDS
Three animal breeds will be used for this study. They include: Katahdin sheep, Dorset sheep and Boer goats. The use of three animal breeds is to establish the existence of species and breed variation in both the incidence of the disease and tolerance to the different treatment regimens. Katahdin hair sheep have the largest number of registrations in the state of Missouri. This breed is attractive because of the absence of wool and the ease of management. It is very suitable for the Ozark region where hickory and oak trees are abundant in the forests. The Dorset breed selected because it is an out-of-season breeder and will produce all year round allowing sheep producers to raise lambs all year rather than seasonally as is observed in all other breeds of sheep. The Boer goat is a meat goat with great musculature and growing ability. This provides a higher percentage of meat in the carcass than other breeds of goats. This breed is a South African import, and is adapting very well to the Midwest environment.
3. CHEMICAL ANALYSIS OF THE HERBS
Detailed compositional analysis of the herbs will be carried out including: total
organic carbon, total organic nitrogen, metals, volatile oils, non-volatile oils, and major active compounds such as santonin and thujone which have previously been reported to be contained in Artemisia absinthium (Skyles and Sweet, 2004; Perez-Souto et. al, 1992). A Shimadzu Total Organic Carbon/Nitrogen analyzer will be used to analyze the total organic carbon and nitrogen. Analysis of the soil and the herbs for all the major minerals will be carried out using the Varian Inductively Coupled Plasma Emission Spectrophotometer (ICP). Sample preparation for ICP will be carried out using the Milestone Microwave digestion system. Analysis of the active compounds in the herbs will be carried out using a combination of gas chromatograph/mass spectrometer (GC/MS), high performance liquid chromatograph (HPLC), and nuclear magnetic resonance (NMR) spectroscopy. The herbs will be ground and subjected to both aqueous and organic solvent extraction. Three organic solvents will be used for the extraction procedure. These are: methanol, acetone, and chloroform. The extracts will be loaded on HPLC and GC/MS systems and analyzed using appropriate columns. Further characterization will be carried out using NMR.
4. EVALUATION OF THE EFFICACY OF THE HERBS ON THE CONTROL OF INTERNAL PARASITES
A group of 150 Boer goat meat goats and crosses, hair sheep (Katahdin breed) and wool sheep (Dorset, the out-of-season breeders) are being reared and monitored for symptoms of internal parasite diseases. The diseased animals will be divided into six groups namely: control group, experimental group 1, experimental group 2, experimental group 3, experimental group 4, and experimental group 5 and experimental group 6. The control group shall consist of animals that will not receive any form of treatment during the period of investigation. Experimental group 1 animals will be treated with a conventional chemical dewormer, avermectin. The animals in groups 3, 4 5 and 6 will be treated with powders of three Artemisia sp with known anthelmintic activity (A. herba alfa, A. absinthium, A. afra), with each group treated with specific Artemisia species. For statistical reasons, each group will consist of 15 animals. The data will be analyzed by analysis of variance in a 3 X 6 factorial design.
Responses of the animals to the treatments will be monitored using both physical and pathological indices. Physical indices to be monitored include: changes in body weight, general mood of the animals, color appearance of the gums and eyelids. The chemical correlations of these physical indices will be estimated using the FAMACHA ® cards and compared to actual values of the pathological indices measured using standard hematocrit procedures. The FAMACHA ® method is named after its South African developer Francois Malan. The method consists of a plastic card featuring five high-resolution photographs of the eyes of infected goats and sheep. Each photograph corresponds to a specific stage of Haemonchus infection with 5 representing severe anemia (Burke, 2006). Effects of the herbs on the immune system will be monitored by measuring immunoglobins IgM, IgA and IgG. Pathological indices to be measured include: changes in the fecal egg population from May to October and changes in fecal protein levels.
Prior to evaluating the efficacy of the herbs, comprehensive dose response studies will be carried out to determine the range of tolerable levels of the herbal levels of the herbs treatment to which the animals will be used to examine the dose response. The doses will include: recommended dose, 2 times lower than recommended, 2 times higher than recommended, 6 times higher than recommended, and 10 time higher than recommended. Dose response will be counts, and other pathological indices.
5. TRANSFORMATION STUDIES OF CHEMICAL COMPONENTS OF HERBS
Analysis of the transformation products of the herbs will be carried out as they go through the stomach, organ system of the animals, and the soil. This will assist in explaining data obtained from environmental impact studies. Blood, feces, and soil samples will be collected and analyzed using GC/MS, HPLC, and NMR. The collected samples will be subjected to both aqueous and organic solvent extractions and the extract analyzed using a combination of HPLC, GC/MS and NMR procedures. Like the herbs, three organic solvents will be used for the extraction procedure. These are: methanol, acetone, and chloroform. The extracts will loaded unto HPLC and GC/MS systems and analyzed using appropriate columns. Further characterization will be carried out using NMR. Results of analyses will be compared to those obtained on the herbs to develop a picture of the transformational pathways and mechanisms.
6. GREENHOUSE STUDIES ON THE HERBS
After identifying what the major components of the herbs are, a greenhouse study of the herbs will be carried out to establish at what point in the plant growth process the active ingredients are synthesized of synthesized maximally. The herbs will be transplanted into pots, and samples of the leaves and stem collected periodically and already described above.
7. ENVIRONMENTAL IMPACT STUDIES OF HERB BYPRODUCTS
Soil organisms play critical roles in the decomposition of organic matter and the release of plant nutrients. Many of them also play important roles in the natural cycles of various elements. Thus, any negative impacts of the byproducts of the herbs on these important residents of the soil need to be established. Environmental impacts of the byproducts on major soil organisms like microorganisms and macro-fauna. Soil samples will be collected from the grazing sites 2 hours after feeding the herbs, and 24 hours after feeding the herbs. Microbial profiles from the site for herbs-fed sheep and goats will be compared with that from the site for the control to establish the impact of the byproducts. Impacts on microorganisms will be confirmed by isolating pure cultures of the microbes and determined their sensitivity to MPLC fractions of the byproducts. Estimation of microbial population will be achieved by aqueous extraction of the soil samples and plating out on enrichment media for the different classes of microorganisms and counting the colonies. Bacteria will be plated out on nutrient agar while fungi will be plated out on potato dextrose agar. Direct identification of microorganisms will be carried out using the Microtox GC FAME systems. Soil micro-fauna population in given soil quantity will be estimated by separating the different species and counting them.
8. HERBS AND SUSTAINABILITY OF GRAZING OPERATIONS
It is the long-term objective of this study to integrate herbs into the overall grazing operations of sheep and goats. To this end the effect of direct planting of herbs on grazing lands on both the control of intestinal parasites and sustainability of the grazing land will be concurrently evaluated. It is well recognized that many of the herbs are bitter and may be ignored by the highly sensitive palates of small ruminants. This study will evaluate different mixed planting strategies that will ensure the unintentional consumption of the herbs along with the main food of the animals. The planting strategy will also ensure consumption of the required quantity of the herbs needed to achieve deworming. The effect of direction consumption of herbs as grazing plant on the control of the parasites will be evaluated by comparing the pathological indices obtained with this approach with those obtained with the crude powder method.
9. COMMERCIAL FIELDEVALUATION AND FARMERS’ INVOLVEMENT
This project places premium value on farmers’ participation. The driving force behind the conception of the project was concern expressed by farmers to Dr. Helen Swartz regarding the inadequacy of current efforts at controlling intestinal parasites. Dr. Swartz works directly with sheep and goat producers as state extension specialist/researcher on small ruminants. In this regard the project has sought and obtained the consent of three commercial farmers as partners in the execution of many of the deliverables especially the one on field evaluations.
The experimental design for the field evaluation is similar to that for the preliminary experiments on George Washington Carver Farm at Lincoln University. Diseased animals on each farm will be divided into three. Each farm will handle evaluations involving one animal species. One group will be treated with conventional anthelmintic drug and the second group treated with the best formulation from the experimental study. The farmers will be trained on how to conduct fecal egg counts and on the use of the FAMACHA ® cards to estimate the stage of Haemonchus contortus infection. Their data will be compared to those obtained by the researchers using analytical procedures.
10. STATISTICAL ANALYSIS
Results from the series of evaluations will be subjected to analysis of variance (ANOVA) and other statistical analysis using recognized statistical package such as SAS. Statistical analysis will include dose comparison, comparison between herbs and comparison between breeds of animals in their response to different treatments.
11. INSTITUTIONAL CAPACITY
This project will be executed as a multi-disciplinary and multi-institutional partnership involving personnel of Lincoln University and Xavier University, Cincinnati, Ohio with expertise in animal science, analytical chemistry, biochemistry, microbiology and the extension service. The scientific team will be working directly with selected farmers in different parts of Missouri.
Lincoln University Cooperative Research Unit has research analytical laboratories that are equipped with a wide array of instrument that will be deployed to ensure successful execution of HPLC system, Milestone microwave digestion system, Varian ICP unit, and Milestone carbon/nitrogen analyzer. The Chemistry Department at Xavier University also has a well-equipped analytical laboratory containing many of the above analytical instrumentation and in additional a functional Nuclear Magnetic Resonance (NMR) machine. Lincoln University also has several acres of experimental farms that will be available for the rearing and grazing of sheep and goats. It also has ultramodern conventional and hydroponic greenhouse facilities that are also available for the use in this study.
12. DISSEMINATION OF RESEARCH INFORMATION
Raising awareness on the potential of herbs as low cost alternative dewormers in sustainable grazing of sheep and goats is one of the cardinal objectives of this study. The project intends to accomplish this through direct involvement in the organization of workshops and training sessions where farmers will be presented with update information about the herbs and the potential benefits of using them in place of chemical commercial dewormers. Dr. Helen Swartz in her capacity as state Extension Specialist/Professor has developed an extensive network with sheep and goat producers in Missouri. We intend to take advantage of this connection to reach the sheep and goat producers with update research results at their local, regional and state meetings.
Lincoln University and University of Missouri, Columbia are the two Land Grant institutions in Missouri. The Extension Units of the two universities enjoy close collaborative relationships. Publications from the units are ready by the majority of farmers in Missouri and are on the web site at both universities. We intend to use the relationship to reach a wider audience of sheep and goat producers by publishing research outcomes in newsletters and other publications by the two extension units. We also intent to present our research findings at the annual small farm trade show and conferences held in Columbia, MO. This is one of the largest gatherings of small-scale farmers and producers in Missouri and participation from the neighboring Midwestern states. Lincoln University conducts a goat and sheep/4-H camp annually that is statewide in draw and we intend to vigorously use conventional means of disseminating scientific information such as publications in scientific journals and magazines and presentations at professional meetings.
1. Three species of Artemesia family, Asteraceae were selected to be grown in the greenhouse to feed to the Katahdin hair sheep, Dorset wool sheep and Boer meat goats in this study to compare to a control, and commercial dewormer, Ivomectin. Artemesia absinthium and Artemesia herba-alba were available in the United States and Canada. Artemesia absinthium grew well but Artemesia herba-alba seeds did not germinate after planting twice. The season was getting too late to plant a third time so we grew the Artemesia absinthium and processed to feed to the sheep and goats from June through September in our comparative trials. Artemesia absinthium grew well in the on greenhouse conditions (21-25o C) ambient temperature and humidity of 75-90% day/night throughout the duration of the project. The herbs were dried at room temperature and ground into powder to add to the grain mixture at pre-determined dosages related to animal body weight. Sheep and goats were grazing throughout the trials on mixed pastures comprised primarily of cool season grass mixed with red clover and weeds.
2. The animals used in this study were Katahdin hair sheep, Dorset out-of-season wool sheep and Boer meat goats imported into the United States in 1993. There were 138 animals In the three breeds. The use of the three animal breeds is to establish the existence of variation in both the incidence of the disease and tolerance to the different treatment groups and regimens. Sustainability is dependent on the sheep and goats ability to survive the hot summer months on pastures provided that are common in our state. The Katahdin hair sheep have the largest number of registrations in the United States in the state of Missouri. It is most suitable in the Ozarks of the state of Missouri to include hair sheep due to the large numbers of hickory and oak trees that are abundant in the forest and sustainability is needed in ridding sheep and goats of the barberpole blood sucking worms in the hot summer months especially from June through September. The Dorset wool sheep was selected because it is an out-of-season breeder and sustainability in a sheep operation calls for lambing year round to produce a saleable product for small farmers. The Boer goat is the meat breed imported into the US in 1993 great musculature and growing ability. The breed is adapting well in the Midwest region
3. Detailed compositional analysis of the herbs has been carried out. Total organic carbon and nitrogen and mineral analysis using the Varian Inductively Coupled Plasma Emission Spectophotometer (ICP) was employed.
4. Efficacy of Herbs on the Control of Internal Parasites of animals were included over the four month collection period of 138 animals, Katahdin hair sheep, Dorset wool sheep and Boer meat goats divided into four groups namely; experiment 1 control, experiment 2, Artemesia absinthium plants grown in the greenhouse at Lincoln University, experiment 3 avermectin (Ivomec), experiment 4, the commercial herbs.
Responses of the animals to the treatments were monitored using both physical and pathological indices. Physical indices monitored included 1) changes in body weight, 2) color of the eyelids using FAMACHA ® hematocrits and the fecal egg counts. The FAMACHA ® method is named after its South African developer Francois Mclan. Each photograph corresponds to a specific stage of Haemonchus contortus, with a 1, red color representing a high count and a 5, white color demonstrating anemia. Immunoglobulins were analyzed taken from blood and no significant differences were reported from the SAS report.
5. Pathological indices measured included changes in fecal egg population from June through September in animals in all four groups. Evaluation of the efficiency of the herbs with levels given in a separate study with animals fed six times the recommended level compared to the comprehensive dose on a select group of sheep and goats revealed no changes in liver and kidney functions.
Analysis of the transformation product of the herbs is on-going with the University of Missouri Veterinary School of Medicine working with Dr. George F. Rottinghaus on the collected samples with both aqueous and organic solvent extractions. Results will be compared to develop a picture of the transformation pathways and mechanisms.
6. Greenhouse herbs showed a major component of the herbs are on-going as the planting occurred in March of 2008. The plants were cut and dried each month from June through present time. The leaves, stems and seed are presently being processed for the active compounds in the plants.
7. Environmental impacts herbs by-products with soil samples are to be collected in 2009 for soil organisms in the decomposition of plants.
8. Herbs and Sustainability of Grazing Operations. Integrating herbs into the overall grazing operation of sheep and goats will be initiated in 2009. The effect of direction consumption of herbs as grazing plants on the control of the parasites will be evaluated comparing the pathological indices obtained with the approval of the crude powder method.
9. Commercial Field Evaluation and Farmer’s Involvement
The project places premium value on farmer’s participation. Three farmers will be designing field’s evaluation similar to the research station experiments.
10. Statistical Analysis- Results of the series of evaluations has been subjected to analysis of variance (ANOVA) using SAS and all studies will be analyzed with SAS. Statistical analysis included dose comparisons between herbs, control, commercial herbs and a commercial dewormer (Ivomec) between breeds of sheep and goats in response to dates from June through September of 2008 and years following.,
11. Institutional Capacity-The project was executed as a multi-disciplinary and multi-institutional partnership involving personnel of Lincoln University and Xavier University of Cincinnati, OH with expertise in animal science, analytical chemistry, biochemistry, microbiology and extension services. Dr. Aaron Baba of Xavier University met with the team to make recommendations for the research conducted in 2008 in his area of study.
Impacts and Contributions/Outcomes
In the short-term, this project will help increase awareness on the positive potential of natural herbs (wormwood) as a low cost substitute for expensive synthetic chemical dewormers with Ivermectin selected for this project since it is a well-rounded commercial dewormer. Katahdin hair sheep, Dorset wool sheep and Boer meat goats were contributing to the knowledge gained. Resistance of the internal parasites is being reported atl Food and Drug Administration’s (FDA) currently in approved dewormers in sheep and goats. The wormwood plants grown in the greenhouse at Lincoln University, Artemesia absinthium used for deworming the sheep and goats in 2008 recorded the lowest fecal egg counts throughout the four month period from June through September comparing the control, commercial dewormer avermectin and commercial herbs.
The sustainable rearing of sheep and goats using natural herbs would be the long-term expected outcome from this three-year study.
The results of this study will be shared with sheep and goat farmers with the positive outcome of 2008. Three years of data are needed to make recommendations to farmers if we repeat positive results the next two years.