dermatophilosis (rain scald,
streptotrichosis, lumpy wool disease) | fleece rot
| staphylococcal dermatitis |
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
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.
- 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.
Diagnosis: A diagnosis can often be made based on the appearance of the
lesions. If this is not possible, a culture or microscopic examination is
Treatment: For effective treatment, the following things should be done:
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.
- 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%).
- 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
Treatment: 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.
- 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.
Diagnosis/Treatment: 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.
- Big Head: See page F120.
- Caseous Lymphadenitis: See page F108.
Fungal Skin Infections:
- 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
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):
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.
- 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.
Viral Skin Diseases
- 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.
Diagnosis/Treatment: 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.
- 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.
- Contagious Ecthyma: See page F129.
Parasitic Skin Problems
- 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
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.
Diagnosis: 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
Treatment: 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.
- 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.
Treatment: 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.
- Mites or Mange:
Introduction: 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
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
The following are some of the most common mites that infect sheep and goats:
- Psoroptes communis ovis (psoroptic mange, sheep scab,
common scabies, or Psoroptes cuniculi):
Introduction: 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:
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.
- 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.
Treatment: Treatment for this problem involves dips and sprays
including lime sulfur, coumaphos, and phosmet (see page
B620 for additional
* A Psoroptes ovis infection is a reportable disease. If this
disease is suspected, local, regional, state, or federal veterinarians should
- Sarcoptes scabiei (Sarcoptic mange, head scabies):
Introduction: 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
Diagnosis: 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: 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
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
- 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.
- 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
- 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
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.
||Identification of Mites
in Skin Scrapings
||Life Cycle (days)
|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.
|Chorioptes communis ovis
|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).
|Sarcoptes scabiei ovis
||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.
||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
|Side, flank, thigh
||Dry, broken wool; hair loss, crusts and
||Round body with indentions between legs,
and long setae and an inward curving spine on each femur.
(legitch; blacksoil itch)
||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
- 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.
Diagnosis/Treatment: 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.
- 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.
- Warts (Papillomatosis)
Cause: 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
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.
Treatment: 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.
Prevention: 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.
- 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*.
- 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
- 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*.
- 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
- 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,