Skin Problems

dermatophilosis (rain scald, streptotrichosis, lumpy wool disease) | fleece rot | staphylococcal dermatitis | dermatophytosis | ulcerative dermatosis | sheep and goat pox | lice (pediculosis) | mites or mange | lumps and masses | nutrition-related skin diseases | wool slip and wool break

Introduction: Skin problems are among the common problems encountered in sheep and goats. This discussion will review many of these. Most of the causes of skin disease that are common to sheep and goats can be placed in one of the following categories: bacterial, fungal, viral, parasitic, lumps and masses, and nutritional problems.

The cause, clinical signs, diagnosis, and treatment for many of the common skin problems in sheep and goats will be discussed in the following material:

Bacterial Skin Infections:

Introduction: Bacterial skin infections occur commonly in sheep and goats. Many of the bacteria that cause problems are normally found on the animal or in the environment. These bacteria often infect the skin when environmental conditions are right and/or when the skin is injured or damaged in some way.

  1. Dermatophilosis (Rain scald, streptotrichosis, lumpy wool disease)
    Cause/Clinical Signs:
    Dermatophilosis is caused by the bacterium (actinomycete) Dermatophilus congolensis. This problem causes hair loss, matting, crusting, and scab formation. The ears, muzzle, face, and tail are commonly affected. Small tufts of hair/wool and crusts can easily be removed, exposing a raw, sometimes infected lesion. Strawberry footrot is the name for this infection when it causes lesions on the lower limbs and legs.

    Disease Transmission:
    This problem is spread by direct contact from animal to animal. It can also be spread when contaminated equipment is not cleaned properly between animals or through contaminated dipping solutions. Insects may also spread the disease from animal to animal. Wet, humid, rainy environments and any situation that causes the surface of the skin to be damaged, increase the chances of developing the problem.

    A diagnosis can often be made based on the appearance of the lesions. If this is not possible, a culture or microscopic examination is required.

    For effective treatment, the following things should be done:
    • Clip the hair from the problem areas if possible
    • Disinfect the lesions with dilute betadine or chlorhexidine
    • Keep the skin dry and exposed to sunlight
    • In severe cases, administer penicillin
    • Topical treatments may also include copper sulfate (0.2%), zinc sulfate (0.2-0.5%), or potassium aluminum sulfate (1%).

    Prevention: Isolating any diseased animals and controlling biting insects are two of the most common preventative measures. Increasing protein, energy, and mineral intakes are also important. In very rainy environments, it is important to provide shelter from the rain.
  2. Fleece Rot
    Causative Agent/Clinical Signs:
    Fleece rot is commonly caused by Pseudomonas aeruginosa. This bacterium causes problems when large amounts of moisture is trapped on the skin by the wool. The injured skin is soft and bluish in color (cyanotic). The back and neck regions of the body are commonly affected. Because no crusts or scabs are formed, it looks different than dermatophilosis.

    Shearing and keeping the skin dry are the best treatments. For severe problems, treatments similar to the ones used for dermatophilosis can also be used.
  3. Staphylococcal Dermatitis:
    Causative Agent/Clinical Signs:
    Infections of Staphylococcus aureus can cause skin lesions around the head, eyes and ears. It can also cause blister like vesicles and pustules on the teats and udder of goats right after they give birth.

    A sample from the affected area must be collected and cultured. Treatment involves topical antibiotic ointments and injectable antibiotics (penicillin or oxytetracycline). It is best to perform a culture and sensitivity before placing the animal on injectable antibiotics. If the udder is affected, the animal should be milked last. Because the infection can spread to other animals, all infected sheep and goats should be isolated from the rest of the herd/flock.
  4. Big Head: See page F120.
  5. Caseous Lymphadenitis: See page F108.


Fungal Skin Infections:

  1. Dermatophytosis (Ringworm, lumpy wool, club lamb fungus): Dermatophytes are a "keratinophilic" (skin-loving) species of fungi which are responsible for the commonly known syndrome "ringworm." Because the disease is not caused by a worm at all, this term is rather misleading.

    Causative Agents:
    The following are different species of dermatophytes that have been found to infect sheep and goats: Microsporum canis, Trichophyton verrucosum, T. gypseum, and T. mentagrophytes.

    Clinical Signs:
    Generally, these fungal infections appear as areas of hair loss, with flaky, crusty, irritated skin. The face, ears and neck are commonly involved. These infections usually cause some degree of discomfort to the animal, resulting in pruritus (itching).

    Sheep and goats can get ringworm from several sources. They can get the fungi directly from other animals or from the soil. They can also be exposed to fungi found on surfaces, such as contaminated equipment, feeders, and bedding. The aggressive shearing and washing of show lambs makes these animals very susceptible to fungal infections.

    A dermatophytosis infection is diagnosed by performing a culture of the hair and skin from an affected individual. This is accomplished by taking hair samples from the outside edge of a few of the lesions. The hair is then placed on fungal specific media and any dermatophytes are allowed to grow. Most cultures can be performed and interpreted by a veterinarian. Results may take up to 10-14 days to provide an accurate answer. Other techniques commonly used include a Wood’s lamp test and direct microscopic examination of hair and scales of affected animals. Wood’s lamp testing involves close examination of the skin of the animal with a special light which causes the hair and skin to fluoresce a bright apple-green color if the animal is infected with a dermatophyte. Wood’s lamp testing is not accurate in all cases. Direct microscopic examination with the aid of potassium hydroxide preparations can also be performed.

    Treatment (choose one of the following):
    • Chlorhexidine (diluted 1:4 in water) applied 3 times a day until resolved.
    • Topical iodine compounds (2-5%) can be applied to the lesions.
    • Captan, a plant fungicide, (mixed 1 ounce of the 50% powder to a gallon
    • of water) applied daily for 3 days and then weekly until resolved.
    • Allow the animal as much exposure to sunlight as possible.
    Prevention and Public Health Concerns:
    Dermatophytosis is "zoonotic," which means that the disease is contagious to people. Care should be taken when an animal is diagnosed with dermatophytosis. Follow the veterinarian’s instructions when treating ringworm. If ringworm is identified as the cause, all bedding, clippers, brushes, and pens must be thoroughly cleaned and disinfected. A 1:10 dilution of household bleach can be used. The fungal spores remain viable for up to 18 months in the environment. Frequent washing of hands and clothing that comes into contact with the affected animal is very important.


Viral Skin Diseases

  1. Ulcerative Dermatosis:
    Causative Agent/Clinical Signs:
    Ulcerative dermatosis is caused by a virus similar to the one that causes contagious ecthyma. This virus often combines with a bacterial infection to cause ulcers and scabs on the feet, mouth, and lips where small abrasions have occurred. Irritation and injury during breeding helps spread the virus from animal to animal causing inflammation of the vulva, penis, and prepuce. These areas may become red, swollen, and inflamed. This problem is most commonly found in sheep.

    A sample or biopsy from the affected area must be collected. Visually, this infection appears different than a contagious ecthyma infection because of the ulcers that are commonly involved. Treatment involves clipping and cleaning the wounds, and then applying topical antibiotic ointments (triple antibiotic). Because the infection can spread to other animals, all infected sheep and goats should be isolated from the rest of the herd/flock.
  2. Sheep and Goat Pox:
    Causative Agent/Clinical Signs:
    Both problems are caused by viruses that are not found in the United States. Each causes vesicles, pustules, and scabs to form on the udder, prepuce, scrotum. Sheep pox lesions are also found on the face. In addition to the skin lesions, these viruses can cause a fever (pyrexia) and the animal to go off feed (anorexia). Goat pox can also cause inflammation of the tissues surrounding the eye (conjunctivitis) and the nose/sinuses (rhinitis). Both viruses can cause death, particularly in the case of sheep pox if the virus affects the lungs or the stomach and intestines.
  3. Contagious Ecthyma: See page F129.


Parasitic Skin Problems

  1. Lice (Pediculosis):
    Introduction and Causative Agents:
    Most lice (louse = singular) infestations occur during the winter months. The infections are often more severe in sick or weak animals. There are basically two categories of lice: ones that bite or chew and ones that suck when obtaining their nourishment. Biting lice can be identified by their round head, while sucking lice have a narrow head. This table identifies the common biting and sucking lice associated with sheep or goat infestations:

    Species of Animal Affected Common Biting Lice Common Sucking Lice
    Sheep Damalinia ovis Linognathus ovillus
    L. pedalis
    Goats Damalinia caprae
    D. crassiceps
    D. limbata
    Linognathus stenopis

    Clinical Signs:
    Lice are parasites of the skin which cause mostly superficial skin inflammation and itching. Many times the itching is so intense that the animal may suffer wool or hair loss, weight loss, and even lameness.

    Diagnosing an infestation of lice is made by identifying the parasite using a microscope. Careful observation of the anatomy of the louse will aid a professional in identifying the specific species causing the infection.

    Treatment of lice infections in sheep and goats is accomplished with the use of dips, dusts, or sprays including lime sulfur, coumaphos, and phosmet (see page B620 for additional details). Injectable products, such as ivermectin and doramectin, can also be used to treat the sucking lice infestations.


  2. Melophagus ovinus (Sheep ked):
    Sheep keds (Melophagus ovinus) are wingless parasites that feed on the blood of animals. Though commonly called sheep ticks, they are not actually ticks. The ked is reddish to grey in color, about 1/4 of an inch long, and has six legs. Most infections occur in the winter months; however, problems can occur year-round.

    Clinical Signs:
    The parasite moves rapidly from animal to animal, with moderate to heavy infections causing severe damage to the wool. It is spread by direct contact between animals. The ked causes damage to the wool in two ways. First, if the parasite load is great enough, the keds will suck enough blood to severely affect the nutritional health of the sheep. This will cause poor wool growth. Secondly, the excrement of the keds will stain the wool a reddish color and pupal stages of the ked can be found in the wool. The ked also causes damage to the skin (often called "cockle") and a pungent smell.

    Controlling this parasite can be accomplished by dipping, spraying, dusting, and using certain pour-ons (see page B620 for additional details). Treatments should be repeated every 14-21 days.

  3. Mites or Mange:
    Scabies, mange, scab, or itch are all terms referring to mite infections that cause inflammation and irritation of the skin and itching (pruritus). Although most species of domestic animals are susceptible to scabies, each species of mites prefer a certain host animal. This prevents a permanent transfer of parasites between different host species. For example, the mite Psoroptes ovis prefers sheep as its host and will not permanently spread to cattle. This fact validates the separate control and eradication programs for sheep and cattle. Both sheep and goats are susceptible to mite infestations. Mange is more common in goats than in sheep, but is considered basically eradicated in the United States (except for demodectic mange). However, in many countries of the world, mange persists and remains a concern for the sheep/goat industry. These infections are most commonly spread by direct contact between animals.

    Generalized mite infections in sheep and goats are sometimes grouped under the common disease term of "mange." Mange is then more specifically broken down based on the species of mite which is responsible for the infection. In sheep and goats, the four types of mange most commonly encountered are psoroptic mange (caused by Psoroptes ovis), sarcoptic mange (caused by Sarcoptes scabiei), chorioptic mange (caused by Chorioptic ovis and C. caprae), and demodectic mange (caused by Demodex ovis and D. caprae).

    Impact of Mite Infections:
    These diseases cause significant losses and waste to the sheep and goat industry wherever they are a problem. Economic losses result from a reduction in the amount of meat and quality of wool/fiber produced. Control and prevention programs are a significant cost to the producer. On a larger scale, mite infections impact the local and international trade of animals.

    Causative Agents:
    The following are some of the most common mites that infect sheep and goats:
    1. Psoroptes communis ovis (psoroptic mange, sheep scab, common scabies, or Psoroptes cuniculi):
      This mite is an important cause of mange in sheep and goats. It can occur at any age, but tends to be more common in adult animals. Most cases in sheep occur in the winter months, but milder infections can occur during the summer. The economic importance of common scabies exceeds any other type and possibly all other types combined. Psoroptic scabies is prevalent in the more temperate climatic zones of the world, including Iceland, Europe, Africa, Middle East, Balkans, Pakistan, India, and South and Central America. Australia, New Zealand, Canada, and the United States have eradicated the disease.

      Clinical Signs:
      The mites live on the skin surface and pierce the epidermis to feed on lymph. Small pustules develop at the puncture sites and these rupture exuding serum that forms a hard, yellow crust. In sheep, this lifts from the skin together with the wool. Often there is a hypersensitivity reaction to the presence of active mites that causes a significant amount of itching (pruritus). In goats, these mites like to infect areas with less hair such as the ears. These areas may experience hair loss (alopecia) and crusting. Sheep often have pieces of wool stuck between their teeth as a result of nibbling. A "nibble reflex," similar to that elicited in sheep with scrapie, may be obtained when rubbing the affected area. There is extensive loss of fleece and the exposed skin is thickened with raw patches. These raw patches are often secondarily infected with bacteria. The lesions occur particularly over the shoulders and sides but can spread over the whole body. The mites are found mostly at the edge of the expanding lesion which is characteristically moist. The lesions observed are the result of a combination of factors, including damage caused by the mites during feeding, the host’s immune responses to the mites, secondary bacterial infection, and self-inflected trauma in response to the irritation. In sheep, three phases of the infection are described:
      • Active winter scab - At peak severity this affects up to three-quarters of the body surface and occurs 6-12 weeks after the initial infection.
      • Active summer scab - This is a slowly progressive disease with increasing severity as winter approaches.
      • Latent scab - This describes a recovery phase following the onset of warmer summer weather. Often all the lesions are completely gone by mid-summer. Unless an effective treatment program has been started, relapse will occur the following winter.
      Diagnosis: In severe, active cases with large numbers of mites present, it is possible to actually see the mites at the edges of lesions. Placing suspected mite infested material on a dark background (i.e. carbon paper, black felt, etc.) will help in observing the tiny, light-colored mites. Unless there is known contact with another infected flock, microscopic confirmation will be required from skin scrapings taken from the animal. Because the mites live on the skin surface, the sample needs to be taken from the superficial or very top layers of skin. The sample should be taken from the edge of the lesion after removing any excess wool/hair. This skin scrapping can be done by using the edge of a scalpel blade with a drop or two of mineral oil on it. The oil will help the mites and debris adhere to the blade. If there is any uncertainty about the sample collected, take another sample from a different area. It is appropriate to include portions of the wool/hair fibers and any skin crusts or flakes in the sample. Once collected, the scraping should be placed in a mite-proof glass or plastic container for transmission to the lab.

      Treatment for this problem involves dips and sprays including lime sulfur, coumaphos, and phosmet (see page B620 for additional details).

      * A Psoroptes ovis infection is a reportable disease. If this disease is suspected, local, regional, state, or federal veterinarians should be contacted.
    2. Sarcoptes scabiei (Sarcoptic mange, head scabies):
      Sarcoptic mange is not found in the United States, but occurs in Europe, Africa, Middle East, Balkans, India, South America, and Central America. The disease generally develops in malnourished animals during late winter and persists for long periods of time. These mites like to infect areas with less hair such as around the eyes and ears. Itching (pruritus) is usually severe, with areas of hair loss (alopecia) and crusting as a result of self-trauma. Goats can have infections that involve the entire body. If the problem has been going on for a long period of time, the skin may appear thickened and raised. Weight loss is not uncommon for animals that suffer severe problems.

      Diagnosing sarcoptic mange usually requires multiple deep skin scrapings. In challenging cases, specific mite treatment products (ivermectin or 1% lime sulfur dips) are often administered and the animal observed to see how it responds to the treatment. If the sheep/goat responds favorably to the treatment, a diagnosis of sarcoptic mange infestation can be made.

      Treatment of sarcoptic mange is usually successful. Weekly lime sulfur dips can be very helpful; usually treatment for 4-12 weeks is sufficient for resolution. Ivermectin is a very effective drug which may be used either orally or as a series of subcutaneous injections.

      Like a Psoroptes ovis infection, this is a reportable disease. If Sarcoptes scabiei ovis is suspected, a local, regional, state, or federal veterinarian should be contacted.
    3. Chorioptes ovis and C. caprae (Chorioptic mange, foot mange) - This type of mite occurs commonly in sheep and goats, but is not considered to be of great economic or pathological importance. In sheep, the mites are found mainly in the interdigital spaces (between the toes), but can extend up the legs to the knees and scrotum. In goats, the mites infect the lower limbs, hindquarters, and abdomen. They can also be found around the scrotum, brisket, and eyes. The disease is generally mild, with some inflammation and pustule development.

      Like a Psoroptes ovis infection, this is a reportable disease. If a Chorioptes infection is suspected, a local, regional, state, or federal veterinarian should be contacted. Treatment is similar to the other mange infections.
    4. Demodex ovis and D. caprae (Demodectic mange, follicular mange) - This infection occurs in sheep, but clinical disease is rare and often of little significance. However, it may be the most common cause of mange in goats. The mites invade and live in hair/wool follicles and sebaceous glands of the neck, shoulders, and body. They cause the development of nodules with exudate. In a few cases, some intense irritation can occur. In kids the infection may spread rapidly. Deep skin scrapings are necessary to provide a diagnosis. Treatment involves weekly dipping (see page B620 for additional details).
    5. Psorergates ovis (Psorergatic scabies, sheep itch mite or mange) - Itch mange has occurred among the Merino breeds in Australia, New Zealand, Argentina, South Africa, and the United States of America. They feed by piercing the surface of the skin (epidermis) and ingesting the exuding fluids. The infected skin is dry, and flaky. Hair and wool fibers break easily, and remaining wool becomes cotted and matted. Like the other forms of scabies, intense itching causes infected sheep to bite, kick, and rub the parasitized areas.

In summary: The diagnosis of these mite infestations requires that a microscopic examination be performed on a scraping sample taken from the animal. For scraping instructions, refer to the information under the "diagnosis" portion of Psoroptes ovis. The main means to prevent the occurrence of mite infections is to avoid exposing non-infected animals to infected animals. There are also many different products that can be used to dip, spray, or shower new and/or suspected animals before mixing them into a clean flock/herd. Details about these products can be found on page B620.

* In the United States of America, psoroptic, sarcoptic, and chorioptic scabies must be reported to state or USDA officials. In most states, infected flocks/herds are quarantined until treated and pronounced free of the disease.

* The following table contains specific details about each type of mite.

  Mites Lesions Identification of Mites in Skin Scrapings
Mange Type Species Life Cycle (days) Length (mm) Early Locations Characteristics Morphological Features
(common scabies)
Psoroptes ovis 10-14 F 0.6
M 0.5
Sheep: rump, shoulders, sides; Goats: around the ears Hair loss, itching, and head shaking Oval body with well-developed, projecting legs. Bell-shaped suckers present on long three-segmented pedicels associated with 1st, 2nd and 3rd legs (male) and 1st, 2nd and 4th legs (female) are diagnostic of this species.
(foot scabies)
Chorioptes communis ovis 14-23 F 0.4
M 0.3
Hind feet, pasterns, lower limbs Crusty, brown, thickened lesions Oval body with long projecting legs. Bell-shaped suckers are present on short non-segmented pedicels associated with all legs (male) and 1st, 2nd and 4th legs (female).
(head scabies)
Sarcoptes scabiei ovis 10-17 F 0.3-0.6
M 0.2-0.4
Head Thick, crusty, wrinkled, hairless areas Oval body with short legs which do not protrude much beyond the body edge. Suckers are present on long, unsegmented pedicels on the 1st, 2nd and 4th legs (male) and 1st and 2nd legs (female), transverse striations present on dorsal surface.
(follicular mange)
Demodex ovis - 0.2-0.4 Eyelids, prepuce, vulva, neck, back Nodules with discharge Cigar shaped; divided into head, thorax (with four pairs of short, stumpy legs) and an elongated transversely striated body.
(itch scabies)
Psorergates ovis 4-5 weeks F 0.19
M 0.17
Side, flank, thigh Dry, broken wool; hair loss, crusts and scales Round body with indentions between legs, and long setae and an inward curving spine on each femur.
(legitch; blacksoil itch)
Trombicula sarcina - - Feet, coronet, pasterns, and lower limbs Traumatized skin, ulcers and crusts Red or orange, 0.2-0.4 mm long. Larvae are parasitic on all species (including man). All legs have seven segments. The body is covered in dense hairs. Unlikely to be confused with any of the above species.


Lumps and Masses

Introduction: Skin tumors and cancers are not a common problem in sheep or goats. When skin cancer does occur, it is commonly squamous cell carcinoma or a melanoma. Another type of lesion that can occur in sheep or goats is a wart (papilloma). Additional details about cancers and warts can be found in the following details:

  1. Squamous cell carcinoma:
    Introduction/Causative Agents:
    Squamous cell carcinoma (SCC) is probably the condition most frequently associated with the term "skin cancer." SCC arises from the most superficial layer of skin and is associated with exposure to excessive sunlight, old scars, and chronic skin irritation. This tumor is more common in older animals and in the Merino breed of sheep. The masses occur on the face, ears, and vulva.

    Clinical Signs:
    Skin in which squamous cell carcinoma arises may appear as an open sore or wound that does not heal, or may occur as cauliflower-like nodules of varying size.

    Histopathology is necessary for a diagnosis. Treatment of SCC most often includes surgical removal of the cancer. Many animals are culled early from the flock or herd. In all cases, it is important to avoid additional exposure to sunlight.
  2. Melanoma and Hemangioma:
    Introduction/Clinical Signs/Diagnosis/Treatment:
    Both melanomas and hemangiomas are uncommon tumors found in small ruminants. They most often appear as raised lesions that vary in color. Histopathology is the primary method of diagnosis, and aggressive surgical removal of the tumor is the treatment of choice.
  3. Warts (Papillomatosis)
    Warts in sheep are caused by papilloma viruses. Viruses have not been associated with warts in goats, however.

    Clinical Signs:
    Warts can be found on the head, neck, teats, ears, and penis. The lesions are white to grey, firm and raised. These lesions are harmless in almost all situations, except where mastitis or pain is involved. These warts are most common in animals under 2 years old.

    Disease Transmission:
    Warts are spread by direct contact from animal to animal. They can also be spread when contaminated equipment such as shearing, ear tagging, or tattooing instruments are not cleaned properly between animals.

    Small warts can be crushed, pinched off, frozen (cryosurgery), or surgically removed. Many of the warts found in sheep and goats are often left alone until the body recognizes the lesions and the immune system clears the problem. This can take many months.

    When an animal has a wart infection, it should be isolated from other animals. Any infected animal should also be kept from rubbing on feeders and posts that may be used by other animals. Cleaning of shearing, tagging, and tattooing equipment with a product like chlorhexidine is essential for preventing the spread of warts.


Nutrition-Related Skin Diseases

Introduction: A number of nutritional deficiencies or excesses can lead to skin disease. Notably among these are deficiencies of vitamin A, zinc, iodine, and copper.

  1. Vitamin A Deficiency: Fresh, green plants contain vitamin A. Because of this, vitamin A deficiency is not very common if the animal has access to green forage. Hair loss, eye problems ("star gazing"), overgrown hooves and diarrhea can be seen with a deficiency. Abortions and still births are also possible. To treat these problems, vitamin A can be given as an injection or as an oral supplement. Non-lactating animals should receive 45-50 international units (IU) of vitamin A per kg of body weight per day. Lactating or pregnant animals may require up to 85 IU per kg per day*.

  2. Zinc Deficiency: Animals with a zinc deficiency may have thickened and irritated skin. They may lose weight, not eat, have swollen joints, and poor milk production. Reproductive performance is also diminished and the testicles of the male may not develop. Diets that contain 20 ppm (sheep) or 50 ppm (goats) of zinc or supplements that contain 0.5-2% zinc are usually sufficient*.

  3. Iodine Deficiency: This problem is often called goiter because of the enlarged thyroid gland that can occur. This problem often appears in young animals at or near the time of birth. Commonly, the lambs/kids may have hair loss and be weak. Abortions, still births, poor milk production, and pregnancy toxemia can occur in adults with iodine deficiency. Iodine deficiency can be diagnosed by evaluating the diet and measuring iodine levels in the blood. If iodine deficiency is diagnosed, then trace mineral supplements that contain iodine can be given. Lugol’s solution (5% iodine) can also be used in lambs/kids that are deficient. The recommended dose is 3-6 drops orally every day for 7 days. Adult animals may benefit from having 1-2 mL of iodine placed on the skin once a week during pregnancy*.

  4. Copper Deficiency: This can be a problem in any age animal; however, young growing animals show the most pronounced signs. In lambs and kids, a syndrome often called "sway back" (enzootic ataxia) occurs. Animals with this condition will be weak, have balance problems, and may not be able to use their hind limbs. In sheep, the wool loses its crimp and takes on a "steely" texture. Hair fibers often become lighter as the problem progresses. Some animals experience watery diarrhea and weight loss. Pregnant animals may abort. Measuring concentrations of copper in the blood and liver can be used to diagnose the problem. If blood levels of copper are less than 0.7 mg/dl or concentrations in the liver are less than 80 mg/kg, then copper deficiency is a problem. To treat this condition, oral supplements, boluses, and injections can be used. Sheep are more sensitive than goats or cattle to copper excesses; therefore, caution should be used when copper is supplemented. The National Research Council recommends that the amount of supplemented copper be 10 parts per million (ppm) of the total diet on a dry matter basis*. This is probably sufficient for goats, but a lower amount should be given to sheep. Regular testing should be done to determine actual copper levels in the supplemented animals.

  5. Photosensitization: This is an inflammatory response of lightly pigmented skin that resembles a sunburn. When certain plants are consumed in the diet, compounds enter the bloodstream and cause a reaction when they are exposed to ultra-violet light from the sun. No matter the initial cause, all animals experience the same external clinical signs. These animals are very sensitive to sunlight (photophobic) and may scratch areas of light or non-pigmented skin most commonly on the ears, around the eyes, and the muzzle. These areas can become swollen, red, irritated, infected, and ooze serum. If sunlight exposure continues, the skin in these problem areas can die (necrose) and slough, leaving an extremely painful lesion. A diagnosis can be made based on clinical signs, blood work, and liver biopsy. To treat this problem, remove the plant source causing the photosensitization, protect the animal from sunlight, and treat any underlying causes. It is also important to prevent additional irritation by flies and other insects.

* Many of the doses and descriptions of the deficiencies came from Pugh DG: Sheep & Goat Medicine, Ed 1, Philadelphia, 2002, WB Saunders.


Wool Slip and Wool Break

Introduction/Clinical Signs: Wool slip is a term that has been coined to describe a problem that is associated with shearing housed ewes in the winter months. Wool slip usually occurs several weeks after shearing and can affect a single animal or a large percentage of the flock. The wool falls out usually leaving a pink bald lesion over the back of the ewe. It is common to see from 1/4 to 1/2 of the ewe’s back without any wool. This unsightly lesion causes much concern to producers who often wonder if their feed or mineral rations are lacking. Wool break is a condition where the wool stops growing and becomes weak. The wool will be lost in a few days to a few months.

Causative Agent: When shorn, ewes will require housing to protect them from the cold winter weather and 15 to 20% more feed than unshorn ewes. If they do not receive the necessary protection and feed, they can suffer cold stress that causes wool slip. When an animal experiences cold stress, an increase in cortisol (natural steroids) occurs. The increased cortisol levels can cause the hair to fall out.

In some flocks, wool slip can be traced to related individuals. This might indicate that genetics play a role in traits such as the thickness of the hide or internal body fat reserves. Club lamb ewes tend to be more prone to wool slip than are wool breeds of sheep.

Wool break is caused by some sort of stress being placed on the animal. This stress can come from a parasite infection or some other disease. Owners should be aware that when a sheep is systemically sick there is a good chance that wool break can develop.

Diagnosis: If after shearing, large bald areas are noticed, it is important to first determine if the sheep are showing any signs of external parasites such as lice or keds. Generally, if sheep have external parasites they are itching and rubbing on feed bunks and fences or chewing at their sides. With wool slip or break, the animal may act completely normal.

Treatment/Prevention: There is really no treatment available once the wool slip/break problem is noticed. Prevention is the best way to avoid these problems. Some owners may not shear their sheep in fear of having a wool slip problem. This concern is offset by the fact that shorn ewes produce heavier lambs that have a higher survival rate than lambs born to mothers that have not been shorn. Adequate nutrition and shelter can also greatly reduce the chances of having a wool slip problem. If the wool slip has resulted from poor nutrition, provide additional feed to increase energy and prevent heat loss. During the winter months, ensure that adequate shelter is provided to protect the shorn ewes from the cold weather. Wool break problems can be avoided by implementing sound management practices, such as vaccinations and de-worming, that help prevent disease.

The information about wool slip was used with permission from J. D. Bobb, DVM, Pipestone Veterinary Clinic, International Sheep Letter, Vol. 18 No. 1, January-February 1998