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A project of the National Center for Appropriate Technology 1-800-346-9140 • www.attra.ncat.org Sheep: Sustainable and Organic Production By Margo Hale, Linda Coffey NCAT Program Specialists Ann Bartlett, Chelsey Ahrens NCAT Interns © 2010 NCAT Contents Introduction ......................1 Breed selection ................1 Feeding ruminants .........3 Reproduction....................8 Health ..................................9 Facilities ........................... 12 Marketing ........................ 13 Organic production..... 17 Economics....................... 20 Conclusion ...................... 22 References ...................... 22 Further resources ......... 22 ATTRA—National Sustainable Agriculture Information Service (www.attra.ncat.org) is managed by the National Center for Appropriate Technology (NCAT) and is funded under a grant from the United States Department of Agriculture’s Rural BusinessCooperative Service. Visit the NCAT website (www.ncat.org/ sarc_current.php) for more information on our sustainable agriculture projects. This publication introduces concerns and practices specifically related to sustainable sheep production. Topics covered include breed selection, controlled grazing, pasture lambing, alternative health management, and innovative marketing of meat and wool products. A list of further resources is also included. Introduction F or the established farmer seeking to diversify, sheep offer a number of benefits. Sheep can easily be integrated into an established farm and are a good complement to cattle. Integrating sheep into a farming operation can also contribute to the economic and environmental sustainability of the whole farm. Sheep will enhance a farm’s biological diversity and may fit economic and biological niches that would otherwise go unfilled. The relatively small investment required, and the gradually increasing size of the flock, also make sheep production a good choice for beginning, small-scale, or part-time farmers. It is important to learn as much as you can before beginning a sheep enterprise. General sheep production information — such as feeding, breeding, and health management — is available in local or state Cooperative Extension Service publications. The Resources section at the end of this publication provides further sources of information, including books, magazines, websites, and organizations. We strongly encourage you to supplement your reading by contacting and visiting sheep producers in your area. Sheep can be incorporated into existing grazing operations with goats, cattle, or horses. In fact, multi-species grazing is useful in increasing pasture efficiency. It has been demonstrated that grazing sheep with cattle can increase total meat production by 24% compared to raising cattle alone, and by 9% compared to raising sheep alone. Sheep production is a good choice for beginning, small-scale, or part-time farmers. Photo by Linda Coffey, NCAT. (Walker, 1994) See the ATTRA publication Multispecies Grazing for more information. Breed selection Breed selection is based on the intended market(s), on local climate, and personal preference. Breeds can be divided into eight categories. What breed(s) you choose to work with will depend on your needs and interests. Common breeds are Suffolk, Hampshire, Rambouillet, and Dorset. Hair sheep breeds include Katahdin, St. Croix, Dorper, and Barbados Blackbelly. All breeds have advantages and disadvantages. Crossbreeding is very common Breed Category Description Example General purpose Good balance between sire and dam traits Dorset, North County Cheviot, Montadale Maternal Good adaptability to more difficult Merino, Rambouillet, Targhee, environments; above-average fleece; Columbia, Polypay primarily found in range areas An Illustrated Guide to Sheep and Goat Production Prolific maternal Very large numbers of lambs (average three or more per ewe); excellent newborn vigor Finnsheep, Romanov Dairy Sheep Sire Large mature size; rapid growth; superior muscling; lower carcass fat Suffolk, Hampshire, Oxford, Shropshire, Texel, Southdown Dairy Specialized for milk production East Friesian, Lacaune Hair (meat) Don’t have wool; adapted to hot, humid climates; parasite tolerant Katahdin, Dorper, St. Croix, Barbados Blackbelly Specialized or long wool Produce colored fleeces or fleeces with other unique characteristics; desired by fiber artists Shetland, Icelandic, Lincoln, Border Leicester, Romney Hobby or rare Not typically used for commercial production; may be raised for exhibition, breeding stock, or to preserve the breed; may possess traits of importance to production in the future Jacob, Cotswold, Navajo-Churro, Gulf Coast Native Related ATTRA Publications Small Ruminant Sustainability Checksheet Table adapted from “Changes in the Sheep Industry in the United States.” 2008. National Research Council. Chapter 2. and allows for lambs to have desirable characteristics of more than one breed. Your farm goals should dictate what breed(s) of sheep you choose and whether or not you crossbreed. It is also important to remember that there is just as much variation among animals of the same breed as there is among animals of different breeds. For more information on the various breeds, contact the American Sheep Industry Association (www.sheepusa.org) or visit the Oklahoma State University livestock breeds web page (www.ansi.okstate.edu/breeds/sheep). The book Storey’s Illustrated Breed Guide to Sheep, Goats, Cattle, and Pigs, by Carol Ekarius, is another good source of breed information. The American Livestock Breeds Wooled Sheep Considerations Hair Sheep Considerations Growth and carcass characteristics Less seasonal than wooled sheep Accepted in the traditional markets Higher lambing percentages than many wooled breeds Produce marketable wool Widely available Some breeds show resistance to internal parasites Heat tolerant No wool to shear or market Don’t have to dock tails Page 2 ATTRA Conservancy (www.albc-usa.org) has information on rare and heritage breeds. For more information and research on hair sheep breeds, see the proceedings of the Hair Sheep Workshop (www.sheepandgoat.com/ HairSheepWorkshop). When selecting animals for your flock, you must first decide what traits are important to you and what the animals will be used for. Find producers with the types of animals that you are interested in. You can locate producers by contacting your local extension agent, searching classified ads in sheep publications, viewing online directories, contacting sheep clubs or associations, or by attending meetings or seminars for sheep producers. Once you have found a producer with sheep for sale, visit the farm to observe the flock and the management. The animals will adapt more easily to your farm if their prior management and environment are similar to yours. To develop a productive flock, it is imperative that you select healthy animals. Never build your flock with animals from a sale barn. These are often animals that have been culled by another producer. There is a reason why they were culled, and you do not want Sheep: Sustainable and Organic Production to bring those problems to your flock. Don’t purchase animals that are limping, look sick, or are lagging behind the others. Always purchase animals that are lively and look alert. Select animals that have sound feet and legs and a proper bite (not over-shot or under-shot). It is helpful to bring an experienced sheep producer to assist you in selecting animals that are likely to be healthy and productive. Listed below are some of the signs of a healthy animal. • Lively manner • Easy movement (no limping, swollen joints, or misshaped or hard udders) • Proper conditioning (not overly fat or excessively thin) • Well-shaped udder and teats Question the producer about the flock. For example, ask what diseases have been problems in the flock, what the vaccination and deworming protocol is, and what criteria are used for selection and culling. Also ask your veterinarian about diseases that could be a problem in your area. To run an efficient operation, it is necessary to identify animals (usually by tattoos or eartags) and keep records. Breeding, reproduction, health, and production records are helpful in identifying which animals are most productive and which should be culled. Sample record-keeping forms can be found at www.sheepandgoat.com. Feeding ruminants Sheep will typically consume two to four percent of their body weight (on a dry matter basis) each day in feed. Animal size, stage and level of production, animal activity, and environmental conditions all influence an animal’s nutritional requirements. A variety of feedstuffs can be used to meet your animals’ nutritional needs. Forage from brush, pasture, and range can be maximized as low-cost feeds. Sheep, as ruminants, convert forage that would otherwise be unusable into high-quality fiber, meat, and milk. Like cattle, sheep are grazers; like goats, they also consume woody browse (tree forage and shrubs) and forbs (herbaceous plants). Sheep are less dependent on harvested grains than dairy cattle, swine, and poultry. Sheep are ruminants, named for the rumen — the largest compartment of the stomach. The health and productivity of sheep, as with all ruminants, depends on healthy rumen function. Microorganisms in the rumen digest fiber, carbohydrates, and protein to supply the animal with nutrients. It is essential that the animals be fed appropriately so that these organisms stay healthy. The rumen organisms require fiber, nitrogen (protein), and energy (carbohydrates). The microorganisms prefer a pH range of 6 to 6.8. The digestion of grain (especially finely ground grains) lowers the rumen pH. If sheep eat too much grain, their ruminal pH can drop too low and make them very sick. The rumen microorganisms are healthiest when sheep are eating high-quality forages such as vegetative pasture. When grain (or more grain) is added to the ration, the rumen needs time to adjust. For more information, see ATTRA’s Ruminant Nutrition for Graziers. Lambing Animal ID Bred Due Lambed No. in litter Sire Comments An example breeding record form. www.attra.ncat.org ATTRA Page 3 Related ATTRA Publications Pastures: Sustainable Management Pasture, Rangeland, and Grazing Management Ruminant Nutrition for Graziers Rotational Grazing Paddock Design, Fencing, and Water Systems for Controlled Grazing Managed Grazing in Riparian Areas Pasture grazing Improving pasture and extending the grazing season are important in forage-based sheep operations. Depending on the climate, it may be possible to improve pastures with cool season perennials (tall fescue, orchardgrass), warm season annuals (crabgrass, dwarf pearl millet), cool season annuals (annual ryegrass, oats, wheat), and a few warm season perennials (bahiagrass, bermudagrass) to provide year-round forage. The addition of legumes (alfalfa, clover, lespedeza, birdsfoot trefoil) to a pasture provides high-quality protein and reduces the need for nitrogen fertilizer. Sheep may also be pastured on small grains or root crops (brassicas). Feeding harvested products such as hay and concentrates (grain) is usually a higher-cost practice. The term “grass-farming” reflects the understanding that the livestock grazier’s primary product is high-quality pasture, the prerequisite for healthy animals and healthy profits. For more information on pastures, see ATTRA’s Pastures: Sustainable Management. a paddock until they have grazed the forage down to a predetermined height, and then rotated to the next paddock. They are not returned to a paddock until the plants have regrown to the height needed for availability and quality. Sheep prefer to eat forage no taller than six inches; forage should be grazed no lower than three inches. Controlled grazing reduces both selectivity and repeated grazing pressure — letting plants develop more foliage before being grazed again — while increasing pasture diversity. Although rotational systems require initial expenditures for fencing and water facilities, many producers report increased profitability based on lower input and feed costs, less dependence on machinery, and improvement and better use of pasture. When grazing sheep, farmers must protect their pastures from being overgrazed. There are several reasons for this. Overgrazing forages: • Eventually kills the plants • Reduces the longevity of the stand and exposes more soil to erosion • Means the animals don’t get enough food • Increases the chance of sheep ingesting infective internal parasite larvae The best grazing system for efficient use of pasture is controlled grazing, or managementintensive rotational grazing. In controlled grazing, pastures are divided into smaller units called paddocks. The sheep are kept in Environmental impacts and sustainable sheep production There are substantial environmental benefits associated with sustainable sheep production. These include low embodied energy in feed — all the energy used during feed production — and low releases of emissions such as carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4). Generally, sustainable sheep production is pasture-based and requires little or no supplemental feed. Producing forage on-site and without the use of energy-intensive inputs including fertilizers, herbicides, and fuels to dry and store feed, generally lowers the embodied energy in sheep feed. When feeding native hay and grains that are produced locally, the energy required Page 4 ATTRA for transportation is reduced further due to shorter distances between the feed source and the sheep. Since fossil fuels are primary sources of greenhouse gas emissions such as CO2, using fewer energy inputs usually reduces emissions as well. Providing sheep with access to pasture forage improves the ecological balance between forage and livestock. Pastured sheep efficiently close the loop between harvesting forage and returning nutrients to the soil, and with less energy than if forage were harvested and hauled from the pasture and manure was then hauled back out onto the pasture. Distributing manure and urine on the pasture also reduces methane emissions from manure slurry. Proper soil and pasture management can also mitigate the release of emissions. Under certain soil conditions, N2O emissions are released from the soil through a process called denitrification. An excessive buildup of manure and urine (nitrogen, ammonium) in water-saturated soils can lead to denitrification and the release of N2O, a greenhouse gas 310 times more powerful than CO2. Rotating animals through pastures and moving feeding, watering, and shade areas will help spread the manure and urine out more uniformly and may help decrease N2O emissions from pasture soils. Sheep: Sustainable and Organic Production • Creates bare spots, creating opportunities for undesirable weeds and erosion. The end result of overgrazing is reduced performance of both the pasture and the animals, as well as health problems for the animals. To prevent overgrazing, farmers should be careful to understock rather than overstock land and always remove animals from a pasture when the pasture is grazed down to about three to four inches. Fresh, clean water must always be available. Adult sheep require approximately one gallon of water per day. In a rotational grazing system, the animals either have access to a central water source available to every subdivision, or water is provided separately to each of the pasture’s subdivisions. This can be a challenge and an additional capital expense. For more information, see ATTRA’s Pasture, Rangeland, and Grazing Management. Fencing When raising sheep on pasture, adequate fencing is essential. Good fencing allows you to control grazing, helps save you the frustration of having to chase sheep back into the pasture, and helps protect against predators. Fencing will also be the greatest expense, other than the initial cost of the animals. Traditional sheep fencing is a four-foot woven wire with barbed wire along the top. Four or more strands of high-tensile electric wire is a more economical fencing choice. Strands of polywire can be used for temporary paddocks. Sheep may have to be trained to electric fences by placing them in a small paddock to “test” the wire. Electric netting is also an option for temporary fencing in controlled grazing systems. Regular checking and testing of fences is necessary, and any problems must be fixed promptly, or sheep will escape. Sheep will respect electric fencing better if it is hot (>3000 volts). These animals are hardest to fence: • Rams • Lambs at weaning • Hungry sheep (not enough forage in their pasture) • Sheep in full fleece Predation Sheep are animals of prey due to their size and nature, so they are susceptible to predation. Predators range from coyotes and mountain lions to neighborhood dogs. The first line of defense should be strong, adequate fencing. But most of the time fencing is not enough. Livestock can be protected by guardian animals, including donkeys, llamas, and most commonly, guardian dogs. The most widely used livestock guardian breeds are Great Pyrenees, Anatolian Shepherds, Komondors, and Kuvaszes. For more information on how to control predators, see the ATTRA publication Predator Control for Sustainable and Organic Livestock Production. Range grazing Rangeland is land historically dominated by grasses, forbs, or shrubs. Rangeland also includes land revegetated and managed like native vegetation. Some rangeland types are natural grasslands, savannas, most deserts, tundra, alpine plant communities, coastal and freshwater marshes, and wet meadows. (USDA, 2003) The natural diversity, topography, climate, and extent of rangelands in the U.S. make rangelands wellwww.attra.ncat.org Photo courtesy of Susan Schoenian, University of Maryland suited to sheep grazing. However, rangelands have historically been over-exploited to the detriment of many range sites, especially in the western U.S. Nowadays, range managers and researchers are making significant inroads toward the development of sustainable rangeland grazing systems that are naturally regenerative; allowing for the production of livestock while restoring sensitive rangeland. About 48% of sheep produced in the U.S. are raised in 10 western rangeland states. (NASS, 2010) Sheep are well adapted to ATTRA Page 5 rangeland grazing because of their body size relative to cattle, their grazing and browsing behavior that relies on a more diverse diet than cattle, and, especially, their ability to graze weedy plants such as leafy spurge and spotted knapweed. Range managers have known for years that grazing can damage rangeland health for decades. Through observation of rangeland ecology and grazing animal behavior, successful grazing managers realize that animal impact can have a positive influence on rangeland health as well. A Great Pyrenees guards his flock. Photo by Susan Schoenian, University of Maryland. A good example of management to positively affect rangeland health is called targeted grazing. According to Launchbaugh and Walker (2006), targeted grazing is the application of a specific kind of livestock at a determined season, duration, and intensity to accomplish defined vegetation or landscape goals. As opposed to good grazing management, which range managers are becoming quite good at, targeted grazing refocuses the results of grazing from livestock production to vegetation and landscape enhancement. (Launchbaugh and Walker, 2006) For more information on targeted grazing and using sheep to control weeds, see the publication Targeted Grazing: A Natural Approach to Vegetation Management and Landscape Enhancement (www.cnr.uidaho. edu/rx-grazing/Handbook.htm). Supplemental feeding Sheep are well adapted to rangeland grazing. Photo by Susan Shoenian, University of Maryland. Copper Sheep are very sensitive to copper. They require lower levels than other livestock. Be sure to feed mineral mixes and other feed products that have been specifically formulated for sheep. Page 6 ATTRA Wintertime or dry-period feeding may include supplements in addition to hay. Grain (corn, barley, oats) is used as a supplement to provide energy. Soybean or cottonseed meal is used to provide protein. Other potential feedstuffs include crop residues such as cornstalks, crops spoiled by wet weather, cull vegetables, and by-products from cereal milling, wheat milling, and food processing. Trace-mineralized salt or other mineral supplements are also needed. It is best to feed calcium, phosphorous, and trace minerals in the grain or in a salt mixture to ensure that the animals actually eat them. Test your Sheep: Sustainable and Organic Production forages to determine their mineral content, and adjust mineral supplementation as needed. Your local Extension agent can have your forage analyzed. Mineral content of forage is quite variable across the country, and the type, stage, and level of production of the animal influences mineral requirements. Therefore, no one mineral supplement formula is right for all locations or situations. It is very important that you consistently offer mineral mix (preferably in a loose form), monitor its consumption, and ensure that all the sheep are in fact eating adequate amounts of the mineral supplements. The website www. sheepandgoat.com has additional resources on proper nutrition and feeding of sheep. Ration-balancing ensures that animals receive the necessary amounts of nutrients (energy, protein, vitamins, and minerals). By using the National Research Council’s The Nutrient Requirements of Sheep (see References) and their chart of the nutrient make-up of various feedstuffs, a producer can determine the amounts of nutrients their sheep should receive. If laboratory feed analysis is available, it should be used instead. Advice from a local Extension agent can be helpful in balancing least-cost rations. Montana State University has a website for balancing sheep rations, www.msusheepration.montana.edu. Body condition scoring Your goal in feeding your animals is to meet their nutritional requirements (economically) and to keep them in a productive condition. One way to monitor the animals’ condition is to assign body condition scores (BCS). Body condition scoring evaluates the body fat reserves of your sheep and is an easy method to evaluate the effectiveness of your feeding program. To do this with sheep, you must use your hands to feel the animal — wool and hair make it impossible to see accurately. Body condition scoring is based on the amount of muscling and fat deposition over and around the vertebrae in the loin region. Scores range from 1 to 5, with 1 being emaciated and 5 being obese. For most of the life cycle of the sheep, the goal is to keep them in moderate condition (3). When ewes are nursing twins some weight loss is expected. Even with good feed, body condition may be a 2. It is a good idea to monitor the body condition of your flock before breeding, before lambing, after lambing (while nursing), and at weaning. You should adjust your feeding program to allow most of your flock to maintain moderate condition. Body condition scoring can also be used to determine market readiness. Body Condition Scores Sheep is extremely thin, unthrifty but agile. Score 1 Skeletal features are prominent with no fat cover. No apparent muscle tissue degeneration. Has strength to remain with the flock. Score 2 Score 3 Sheep is thin but strong and thrifty with no apparent muscle structure wasting. No evident fat cover over the backbone, rump, and ribs, but skeletal features do not protrude. Sheep are thrifty with evidence of limited fat deposits in fore rib, over top of shoulder, backbone, and tail head. Hipbone remains visible. Moderate fat deposits give the sheep a smooth external appearance over the shoulder, back, rump, and fore rib. Score 4 Hip bone is not visible. Firm fat deposition is evident in brisket and around the tail head. Score 5 Sheep are extremely fat with the excess detectable over the shoulder, backbone, rump, and fore rib. Excess fat deposits in brisket, flank, and tail head regions lack firmness. Sheep appear uncomfortable and reluctant to move about. Table adapted from the “Sheep Production Handbook.” 2006. www.attra.ncat.org ATTRA Page 7 How many rams do you need? You should have one mature ram for every 35 to 50 ewes. Ram lambs (7 to 12 months) can service 15 to 30 ewes. Reproduction Breeding Female sheep (ewes) reach puberty between 5 and 12 months of age, depending on the breed and nutrition of the ewe, and should be at least 70% of their mature weight at breeding. Most sheep are seasonal breeders, reacting to shorter days as a cue for breeding. The presence of a ram stimulates the reproductive cycle (estrus). The typical peak time for breeding is the fall (October-November), and ewes come into heat every 16 to 17 days. Gestation is about 150 days. Breeding and lambing should be planned based on many factors including the following. • Market demands (What type and size of animal will you market and when?) • Available forage • Timing (Do you want to lamb in January or March?) • Production system (Do your animals breed out of season; do you want multiple lamb crops in a year; are you lambing on pasture or in a barn?) • Climate (Is shelter available?) While the ram is often overlooked, he is the most important member of the flock. Your ram influences every lamb in your flock. Having a quality ram, with the traits you want, is important to building a productive flock. Rams reach puberty between five and seven months, at approximately 50% of their mature weight. It is wise to have a breeding soundness exam (BSE) performed on your ram. A BSE can be conducted by your veterinarian or other trained professional. The exam consists of a physical evaluation of the ram (lameness, body condition, general health, scrotal circumference) and semen evaluation (sperm count, motility, and morphology). It is also important to observe rams for breeding behavior. A breeding soundness exam will not indicate libido. You can use a marking harness to assess breeding behavior and effectiveness. Exposure to high temperatures can cause a ram to be temporarily sterile (up to 10 weeks). Shade and shearing can help keep rams cool. Males of breeding age are unpredictable and may be aggressive. Rams should never be trusted, even if they were hand raised. In fact, hand-raised rams can be more dangerous because they lack fear or respect for humans. Behaviors that were fi ne when they were small (butting, rubbing) can be dangerous in a full grown ram. Never turn your back on a ram. If you are raising rams, don’t touch their heads, and don’t try to make them pets. Lambing In general, ewes will lamb with no assistance and with no problems. Good nutrition and plenty of exercise will prevent many birthing problems. Optimum lambing time varies depending on the production and marketing situation. Photo by Linda Coffey, NCAT. Page 8 ATTRA Lambing can be done in sheds or barns or on pasture. Pasture lambing reduces the need to invest in buildings and equipment and is more appropriate for low-input systems. Southern flocks will have less difficulty with inclement weather than those in colder climates. Disease occurrence may be lower with pasture lambing than with shed lambing because disease agents are not concentrated as they are in confinement. Disadvantages Sheep: Sustainable and Organic Production of pasture lambing include greater risks of parasites and losses from bad weather and predators. Optimum lambing time varies depending on the production and marketing situation. By timing lambs to be born around the same time as the spring flush of growth in the pasture, ewes can have adequate forage during their peak period of lactation. This will also cut down on the supplemental feed ewes need. However, some producers have noted that lambs born later in the spring do not grow as well as lambs born earlier, which may be due to parasites. Lambs born later are just starting to graze as parasite numbers on pasture are increasing. Earlier lambs have a chance to grow and develop their immune systems before they have the parasite pressure of spring and summer grazing. If lambing occurs early in the year (January to early March), ewes will need high quality hay and possibly other supplements to meet the needs of lactation. Evaluating your costs may help you decide on the best lambing season for your farm. Lamb management It is crucial that newborn lambs receive colostrum (first milk) as soon as possible (ideally, in their fi rst 12 hours). Monitor lambs to make sure they are nursing and have bonded with the ewe. It may be necessary to remove a lamb(s) from the ewe if she does not have enough milk for her lambs. Ewes should have enough milk for twins, but some ewes might not be able to raise triplets or quadruplets. Lambs that have had enough milk feel heavy when you lift them, with slightly rounded bellies. They will seem content after nursing and strong, lively, and playful. Lethargic lambs or crying lambs may be a sign they are not nursing or are not getting enough milk. Starvation is a leading cause of death in the first two days of a lamb’s life. It is important to monitor lambs for health issues such as coccidiosis and internal parasites. For information on castration and tail docking, see ATTRA’s Illustrated Guide to Sheep and Goat Production. Growing lambs www.attra.ncat.org need high quality forage. In a rotational grazing system, let weaned lambs graze a pasture first. This will ensure they are getting quality forage and also grazing pastures with lower parasite numbers. Health Starting with healthy sheep and properly maintaining them with adequate nutrition and clean living conditions will prevent most health problems. In addition, vaccinations and low stress handling will assist in keeping a flock healthy. Observe your animals and respond quickly to any health problems — isolate animals at the first sign of illness. Indications of a sick sheep include lethargy, isolation from the flock, loss in body condition, abnormal manure, runny nose, and huddled posture. It is important to have a working relationship with a veterinarian. A veterinarian can help with preventative care and proper treatment of disease. To locate a veterinarian who works with sheep, contact the American Association of Small Ruminant Practitioners: (334) 517-1233, www.aasrp.org. Related ATTRA Publications Managing Internal Parasites in Small Ruminants Tools for Managing Internal Parasites in Sheep and Goats: Copper Wire Tools for Managing Internal Parasites in Sheep and Goats: Sericea Lespedeza Integrated Parasite Management for Livestock Even with proper management, sheep will sometimes have health problems. Keeping health records will help you to identify animals that have repeated health problems. Culling those animals will result in a stronger flock. The following is an overview of some common health problems that affect sheep. Internal parasites For many sheep producers, especially those in humid climates, internal parasites will be the primary health concern. Animals with severe internal parasite loads will be unthrifty, won’t gain weight, are often anemic, and may die. Due to overuse of dewormers and parasites’ increasing anthelmintic resistance, management of internal parasites is a complex problem. Sheep producers must be knowledgeable about internal parasites, and they must have a plan to prevent and manage parasite infections. Because of the complex nature of internal parasites, managing them will take an integrated approach. A combination of treatment and management ATTRA Page 9 is necessary to control parasitism so that it will not cause economic loss to the producer. Parasite management tools may include the following: • Pasture management * Use pasture rotation with adequate rest periods. * Employ multi-species grazing. * Provide taller forages and browse. * Put susceptible animals (lambs) on pasture before mature animals. • Animal selection * Use breeds and animals that show resistance to parasitism (pay special attention to rams). * Cull animals that are frequently “wormy.” • Selective deworming (only treating animals that need it) * Use FAMACHA© to identify wormy animals. FAMACHA© is a system for classifying animals into categories based upon levels of anemia (a sign of H. Contortus infection). * Be alert to other physical signs of parasitism and deworm as needed. • Strategic deworming * Deworm ewes at lambing time. * Treat lambs because they have little resistance. * Deworm all new animals. • Effective use of dewormers * Use the Smart Drenching technique. (www.scsrpc.org/SCSRPC/Files/Files/ Misc/DRENSHIN.PDF) • Novel treatments * Treat animals with copper wire boluses. * Provide forages containing condensed tannins (sericea lespedeza). For more information on managing internal parasites, see ATTRA’s Managing Internal Parasites in Small Ruminants and visit The Southern Consortium for Small Ruminant Parasite Control website: www.scsrpc.org. Foot rot Foot rot is a contagious disease caused by bacteria that affect the horny hoof tissue. Once foot rot is introduced into a flock, it is very difficult to eradicate. Foot rot is spread from an infected sheep to the ground and bedding, where it is picked up by uninfected sheep. Foot rot is characterized by limping animals and pockets of foul-smelling infection in the hoof. Other things can cause limping; have your veterinarian examine the animals if you are unsure of the cause of limping. Foot rot can easily be prevented by not introducing it to your flock. Never buy a limping animal or one from a flock with any limping animals. Don’t purchase sheep from sale barns. Practice good biosecurity; isolate new purchases for 30 days and examine their feet during that time; wear boot covers when visiting other sheep producers and have them do the same. Cull animals with repeated foot rot problems. Animals will pick up more parasite larvae when they graze forages shorter than four inches. Photo by Linda Coffey, NCAT Page 10 ATTRA Hoof trimming and foot baths are common treatments for foot rot. All affected hoof tissue should be trimmed away. Remember to disinfect the trimming tools between animals Sheep: Sustainable and Organic Production