N.C. State Fair, Disease and Condition
Disease conditions likely to prevent livestock (cattle, sheep, goats & pigs) entry into North Carolina fairs (summer – fall 2010) (pdf)
Derek Foster, DVM & Jim Floyd, DVM
NC State University College of Veterinary Medicine
Dept. of Population Health & Pathobiology
The outline which follows contains information on the most likely conditions to cause cattle, sheep, goats and pigs (this discussion does not include horses, poultry, birds and rabbits) to be refused entry to a fair, but it is not an exhaustive list. Usually such conditions are infections with microorganisms such as viruses, bacteria, fungi, or parasites. If the veterinarian or animal health technician examining an animal when checking in to the fair determines that an animal is showing clinical signs typical of infectious disease, he or she may not be able to provide a firm, final diagnosis of the exact cause or causes of the condition. For example, an animal which is depressed, off feed, and febrile could have several different types of infectious disease. In such cases they may be denied entry because these are common signs of infectious diseases, such as pneumonia, which could be contagious to other, healthy animals at the fair. However, an exact diagnosis of the cause of the disease, or a specific causative microorganism will likely be beyond the capabilities of the fair staff to diagnose. Similarly, an animal with a skin condition which looks like “ringworm” or skin fungus (also known as a “dermatophyte”) but may otherwise appear healthy will be denied entry because it could spread this condition to other unaffected animals if it were allowed to enter the fair.
The veterinarians examining animals at entry will be as thorough and consistent as possible as they work in the best interest of all concerned. They will exercise their professional judgment in every case to make sure that only healthy animals are admitted, which may result in an animal with a questionable disease status being denied entry. Although this is unfortunate, it is necessary to insure that the animals at the fair are kept in as healthy an environment as possible for both animals and people.
If there is any question about the health status of an animal, it should be examined by a local veterinarian before transporting it to the Fair. If there is doubt about an animal’s disease status, it should not be brought to the fair. Although an animal may have been properly treated for a disease, this is not justification for allowing entry of an animal which is still exhibiting signs of a contagious disease. Some conditions, particularly those of the skin, may still be contagious for weeks after treatment, thus these animals should not be transported to the fair.
I. Cattle
A. Ringworm
B. Warts
C. Hairy Heel Warts
D. Diarrhea
E. Pneumonia/Respiratory Disease
II. Sheep
A. Ringworm – “Club Lamb Fungus”
B. “Soremouth” (also known as “Orf” or Contagious Ecthyma)
C. Warts
D. Diarrhea
E. Pneumonia/Respiratory Disease
F. Abscesses
III. Goats
A. Ringworm
B. “Soremouth” (also known as “Orf” or Contagious Ecthyma)
C. Warts
D. Diarrhea
E. Pneumonia/Respiratory Disease
F. Abscesses
IV. Pigs
A. Ringworm
B. Mange
C. Diarrhea
D. Pneumonia/Respiratory Disease
Background Information
2010 North Carolina State Fair Health Regulations
“Any and all animals not meeting the entry requirements and/or exhibiting any signs of disease or illness, may be refused entry, required to be isolated and/or required to be returned to the farm of origin. Any and all animals exhibiting any signs of disease or illness or found not to have met entry requirements after entry may be required to be isolated and/or returned to the farm of origin.“
Some definitions:
- Infectious disease – A disease caused by a microorganism such as virus, bacteria, or fungus.
- Contagious disease – A disease caused by a microorganism which is transmitted readily from one animal to another either directly (by animal-to-animal contact) or indirectly (from one animal to the environment and then to another animal)
- Zoonotic disease - An infectious disease in animals that can be transmitted to people.
- Lesion – an area of living tissue, such as the skin, which is altered by disease or injury.
- Clinical signs –the outward appearance of a disease in an animal, in other words how the animal appears to an observer. Examples of clinical signs are skin lesions, behavior (for example off feed), diarrhea, fever as shown by elevated temperature as measured by a rectal thermometer, and coughing. In order to determine a definitive cause of such clinical signs, laboratory tests are usually required.
I. Cattle
(1) Description
Ringworm is a contagious skin disease caused by several types of fungi (more than one fungus = fungi) that infect the outside layer of an animal’s skin and shafts of hair or wool. The name “ringworm” comes from the common round appearance of a new skin lesion caused by a fungus. It is not caused by a parasitic “worm” which has burrowed in the skin. These fungi originate in the soil and can remain viable for years.
Spores of fungi (plural of fungus) in the soil may cause skin lesions in cattle as they do in sheep. A Trychophyton fungus is the most common cause in cattle although there can be several others. Spores which come in contact with skin of cattle will germinate and grow into hair shafts. The skin lesions are often patches of hair loss with a gray or white crust, and occur most commonly in calves although occasionally in older animals. The lesions commonly occur on the head and face because animals rub their heads on posts or equipment where other infected animals have rubbed themselves, thereby spreading the fungus to uninfected animals. Ringworm tends to be more common in the winter. Cattle showing signs of the disease are likely contagious to other cattle. As with “Club Lamb Fungus” in sheep, ringworm in cattle can also be a zoonotic disease which spreads to humans.
The diagnosis of ringworm is based on the characteristic clinical appearance of the lesions on the skin and hair. Because the fungus grows outward from the initial site of infection, the lesions are often first noticed as a circular area on the head, ears, neck and sides. New lesions may feel raised and stiff because of clumping of hair and scabbing of skin, sometimes oozing a clear or bloody fluid. These lesions are often referred to as “active” lesions, meaning that they may be more likely to be the source of infection to other animals and people. As the lesions progress, the hair will be lost. When new growth of hair is visible a lesion is usually considered to be healed, or “not active.” However, this is a judgment call since some lesions may show signs of healing while others may be active. Cattle with signs of previous infection which appear to have healed with new hair growth may be allowed entry, but this is a judgment call on the part of the Fair veterinarians.
Image: Ringworm
(2) Prevention
Disinfecting equipment such as halters and grooming gear as well as premises may reduce the transmission of fungus spores causing ringworm. Removing organic debris from equipment and surfaces animals come into contact with is a first step. This can be followed up by spraying the equipment and surfaces with a strong household bleach solution (1 part bleach to 3 parts water) to reduce the fungal contamination. As this is a strong bleach solution, care should be taken to avoid contact with skin or any surface that may be damaged by bleach.
(3) Treatments (if any)
Many treatments have been applied directly to ringworm lesions in cattle but their effectiveness is difficult to verify because most lesions eventually heal on their own. To be effective, frequent treatment is usually recommended. Povidone - iodine scrubs such as Betadyne, dilute solutions of commercial chlorine bleach (1 part bleach to 10 parts water), and commercial human “athlete’s foot” creams have all been recommended as well as numerous other topical treatments. Refer to the references below and consult with your veterinarian for his/her recommendation on treatment. Animals that have been treated but still have lesions are likely to be denied entry to a fair.
(4) Other information & references
Merck Veterinary Manual. Dermatophytosis (cattle)
http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/71302.htm
Morter, R.L. and Callahan, James. Ringworm of Cattle. Purdue University Cooperative Extension publication VY-56
http://www.ces.purdue.edu/extmedia/VY/VY-56.html
(1) Description
Warts are growths on the skin and mucus membranes (areas without hair in the nose or reproductive organs) of cattle caused by a virus spread by direct contact between cattle. Therefore warts are both an infectious and contagious disease which will cause an animal with clinical signs to be denied entry to a fair. In cattle warts are caused by at least six different types of papillomavirus. These viruses are species-specific for cattle, thus they do not cause disease in other livestock or humans. Wart lesions in cattle are growths which vary in size and shape, some being fairly flat on the skin and others being raised on stalk-like projections with a cauliflower-like surface. They can occur anywhere on the body but are usually noticed on the nose, face, ears, neck, sides, and teats. Halters, combs, brushes and ear tattoo implements may spread the virus between animals if these tools are not properly disinfected. Ear tattoo sites can become covered in warts if tattoo implements have not been disinfected between animals in an infected herd. Warts on the penis are not uncommon in young bulls raised in groups who mount each other, although these are often not noticed until the bull undergoes a Breeding Soundness Exam before sale. Young animals are most commonly affected with warts and will eventually develop an immune response against warts, thereby causing their regression. For the most part, warts do not cause serious health problems but. because they are a clearly noticed blemish caused by an infectious agent, affected animals are not eligible for health certificates. This makes warts primarily a problem in pure bred herds or show cattle. Warts on the penis of bulls are potentially serious because they can physically prevent the bull from breeding females, or bleeding from the warts can seriously reduce their semen quality. In rare cases, animals will have large masses of warts which may create physical problems with eating or other functions. These individuals may have compromised immune systems.
Bovine Warts 1
Bovine Warts 2
Bovine Warts 3
Bovine Warts 4
Bovine Warts 5
Warts
(2) Prevention and Treatment
In most cases warts will disappear when the young animal’s immune system eventually develops a response to the virus. This may explain the effectiveness claimed for various treatments when the actual cause of success is the animals own immune system. Cutting warts off with side cutters or blades, or pinching them off with pliers or forceps has been advocated, both as a method to remove and to “self vaccinate” the animal. It is theorized that such procedures liberate virus from the warts and send them into the blood stream, thus exposing the animal’s immune system to the virus. It is felt that the intact warts “protect” the virus, which prevents the immune system from mounting a response to it. If warts are removed in this way, follow up with a topical wound treatment or fly spray. Some recommend cauterizing the bleeding lesions after wart removal with silver nitrate sticks. Commercial wart vaccines are available but have variable results because they may not contain the specific type of virus causing warts in every case. They may be used to prevent warts from occurring in young, unaffected animals and are often used in animals already showing clinical signs of warts. In such cases it has been recommended that vaccines be repeated at frequent intervals. Alternatively, an “autogenous” bacterin, or vaccine may be prepared by a veterinarian from warts collected from a herd. These vaccines may theoretically be more effective because they contain the specific virus causing the warts in a particular herd.
To limit or control the spread of warts in infected herds, tack, equipment, and grooming or health implements should be disinfected between animals. Cleaning organic debris from such implements will help but should be followed by disinfection with dilute commercial bleach or formaldehyde solutions. See the references below for more information.
(3) Other information & references
Merck Veterinary Manual. Papillomas (Warts).
http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/72214.htm
Morter, R.L. and Horstman, L. Cattle Warts - Bovine Papillomatosis. Purdue University Cooperative Extension Service Publication VY-V8.
http://www.ces.purdue.edu/extmedia/VY/VY-58.html
Pence, M. Cattle Warts and Show Cattle. University of Georgia Extension.
http://www.ads.uga.edu/extension/beefteam/pdf/MWarts.pdf
C. Hairy Heel Warts (Papillomatous Digital Dermatitis)
(1) Description
“Hairy Heel Warts” (HHW) (also known as Heel warts, Strawberry Foot Disease and the more correct medical term Papillomatous Digital Dermatitis) causes severe lameness in all cattle but primarily dairy cattle. The condition first appeared in Europe in the 1970’s and then in the U.S. in the 1980’s. By the 1990’s HHW was present on dairy farms in all parts of the country. It is more prevalent on larger dairies and is associated with wetness, mud, and importation of new animals, most commonly replacement heifers. Beef cattle are rarely affected although there have been more cases of the disease in beef cattle in recent years. The painful lesions tend to occur more commonly on the back of the rear feet above the heels and sometimes on the front of the feet in the cleft between the claws. Lesions often have projections appearing like warts with hairs, thus prompting the common name for the condition of Hairy Heel Warts.
The lesions respond to treatment with antibiotics, both topical and injected. The disease is clearly contagious because importation of infected animals introduces HHW to previously unaffected farms. A spirochete bacterium (Treponema) may be involved in the infection, perhaps working in combination with other bacteria to cause the typical HHW lesions. Because of the highly contagious nature of HHW, cattle showing clinical signs will be denied entry to fairs.
Hairy Heel Warts Image 1
Hairy Heel Warts Image 2
Hairy Heel Warts Image 3
Hairy Heel Warts Image 4
(2) Prevention
Do not allow entry of cattle with clinical signs of HHW onto the farm. Although a vaccine for HHW is commercially available, it has not been demonstrated to be consistently effective when tested in independent trials. Preventing spread of HHW to uninfected animals is the reason that animals showing clinical signs will be denied entry to fairs.
(3) Treatments
Spraying feet of dairy cattle with antibiotic (tetracycline or lincomycin) solutions while they are in the milking parlor has generally been found to be the most cost effective method of treating HHW on a herd basis. These are “extra label” uses of these drugs and should only be done under the advice of a veterinarian who has a valid veterinarian-client-patient relationship with the farm. Antibiotic or formaldehyde foot baths may be used but can spread the disease if footbaths are not changed out often, and use of formaldehyde has human health implications. See the references below for some of the specific recommendations on treatment formulations and uses.
(4) Other information & references s
Ames, K. Michigan State University. Hairy Heel Warts (Papillomatous digital dermatitis).
http://cvm.msu.edu/alumni-friends/continuing-education/extension/dairy/articles-and-bulletins/hairy-heel-warts-papillomatous-digital-dermatitis
Steevens, B. and Underwood, J. North Dakota State University Extension Service. Hairy Heel Wart.
http://www.ag.ndsu.nodak.edu/aginfo/dairy/Health/hairywart.htm
Wallace,R. University of Illinois.
http://www.livestocktrail.uiuc.edu/uploads/dairynet/papers/HairyHeel.pdf
(1) Description
Diarrhea occurs most commonly in young calves and, when it does, is commonly known as “scours”. Iit can, however, occur in cattle of any age. Loose or watery manure is associated with a number of infectious agents, including viruses, bacteria, and parasites such as “worms” and coccidian (single cell protozoan organisms). Diet can cause loose manure without an infection being present, as is seen in cattle grazing lush green spring grass. Cattle with “grain overloads” due to ingestion of a diet high in concentrates can show signs of diarrhea without an infectious agent being present.
Because many causes of diarrhea are infectious and contagious in nature, in most cases these animals will not be allowed into a fair. An animal with diarrhea can contaminate the environment surrounding it, including bedding, feed, flooring, and water troughs, thereby potentially exposing large numbers of other animals in close quarters in a livestock exhibition facility. Although many animals with infections causing diarrhea may have a fever, the absence of a fever cannot rule out an infectious or contagious cause. Therefore, an animal with diarrhea will likely be denied entry to a fair even if it does not have an elevated body temperature as determined by a rectal thermometer.
(2) Prevention
Work with your veterinarian to develop a preventative herd health program, including parasite control and routine vaccinations for IBR/BVD/PI3/BRSV, Leptospirosis and Campylobacteriosis in the breeding herd, Clostridial (Blackleg) vaccine for all calves, and IBR/BVD/PI3/BRSV vaccination before weaning and sale of feeder calves.
(3) Treatments
If diarrhea is a problem in the herd, work with your veterinarian to determine a definitive diagnosis so the specific problem causing the condition can best be dealt with.
(4) Other information & references
Merck Veterinary Manual. Diarrhea in Neonatal Ruminants (scours). http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/22108.htm&word=diarrhea%2ccattle
Merck Veterinary Manual. Other Intestinal Diseases of Cattle.
http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/22105.htm
E. Pneumonia/Respiratory Disease
(1) Description
As with diarrhea in cattle, pneumonia or respiratory disease can be caused by a number of different infectious agents including viruses, bacteria, and occasionally even parasites. Most of these causes are contagious. Since the causes of respiratory disease in cattle are so many and varied and the clinical signs can vary so widely, it is best described as a “complex.” Often the term Bovine Respiratory Disease Complex (BRDC) is used to describe respiratory disease in cattle. Cattle showing clinical signs of BRDC such as coughing, nasal discharge (“snotty nose”), rapid breathing, and an elevated rectal temperature will be denied entry to a fair.
(2) Prevention
There are management strategies to reduce the chances of BRDC in cattle, including vaccination, weaning calves before shipment and sale, and isolation of new arrivals on farms for a period of time. Prevention of BRDC should be part of a comprehensive herd health and management program. Work with your veterinarian to develop such an overall program, including a breeding and calving plan, parasite control, and routine vaccinations for IBR/BVD/PI3/BRSV in the breeding herd and IBR/BVD/PI3/BRSV vaccination before weaning and sale of feeder calves.
(3) Treatments
Promptly examine any animal showing signs of BRDC. Animals with an elevated rectal temperature (usually thought to be temperatures > 104°F) ) should be treated with an injectable antibiotic approved for treatment of the major infectious agents causing BRDC, and treatments should be repeated for an appropriate number of times to insure there is no relapse. Many times treatments are not continued long enough and the disease is not eliminated. Consult your veterinarian on which antibiotics to use, the dosage for the weight of animal involved, and the number of treatments and time between each in such cases. Always remember the pre-slaughter withdrawal times after using any drug in livestock.
(4) Other information & references
Merck Veterinary Manual. Bovine Respiratory Disease Complex: Overview
http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/121205.htm
II. Sheep
A. Ringworm – “Club Lamb Fungus”
(1) Description
Ringworm is a contagious skin disease caused by several types of fungi (more than one fungus = fungi) that infect the outside layer of an animal’s skin and shafts of hair or wool. The name “ringworm” comes from the common round appearance of a new skin lesion caused by a fungus. It is not caused by a parasitic “worm” which has burrowed in the skin. These fungi originate in the soil and can remain viable for years.
Ringworm was relatively uncommon in sheep until about 20 years ago when a more serious form developed in the western U.S. in lambs showed at fairs and exhibitions. This “Club Lamb Fungus” spread to other regions of the country and is now seen often in most places where sheep are exhibited. It is spread between sheep by clippers, brushes, combs, blankets and anything that can serve as a vehicle to transport the fungus from one animal to another. Close shearing of lambs irritates their skin and may facilitate the spread of the fungus. The fungus is relatively slow growing, taking from one to four weeks to cause visible disease after first contact with the skin. The affected lesions usually do not cause the animals to itch.
The diagnosis of ringworm in sheep is based on the characteristic clinical appearance of the lesions on the skin, hair and wool. Because the fungus grows outward from the initial site of infection, the lesions are often first noticed as a circular area on the head, ears, neck and sides. New lesions may feel raised and stiff because of clumping of wool and scabbing of skin, sometimes oozing a clear or bloody fluid. These lesions are often referred to as “active” lesions, meaning that they may be more likely to be the source of infection to other animals and people. As the lesions progress the hair or wool will be lost and replaced by a darker pigmented wool with healing. When new growth of wool is visible a lesion is usually considered to be healed, or “not active.” However, this is a judgment call since some lesions may show signs of healing while others may be active. A lamb with signs of previous infection which appear to have healed with new wool growth may be allowed entry, but this is a judgment call on the part of the Fair veterinarians.
Ringworm is zoonotic, being spread from sheep to humans, with children more commonly affected. Humans may contract ringworm on their hands, arms, necks, faces or elsewhere after contact with infected lambs or items having been in contact with them. The lesions will eventually resolve with time. Topical anti-fungus medications applied directly to the spots daily may hasten healing and reduce discomfort associated with infections.
Club Lamb Fungus: Image 1
Club Lamb Fungus: Image 2
Club Lamb Fungus Image 3
Club Lamb Fungus Image 4
Club Lamb Fungus Image 5
Club Lamb Fungus Image 6
Human Ringworm Image
(2) Prevention
Physically isolate new additions to a farm for 30 days before mixing with animals already on the farm. Before removing from isolation, provide an added degree of protection by spraying or dipping the entire lamb in a solution of .5% chlorhexidine (Nolvasan®) made by adding 3 ounces to a gallon of water. (NOTE: this is inactivated by soap). Use a sponge to apply to the face of the animal. Consider using the same solution to spray/dip animals returning from fairs before reintroducing them onto the farm.
Do not introduce animals with signs of recent ringworm infection onto the farm. Even animals with healed lesions may be carrying infectious fungi. Isolate any affected animals until new wool is growing on old lesions.
Disinfect clipper blades and other grooming implements between lambs when shearing, clipping or fitting for show. Pens and equipment should also be disinfected if they have housed infected sheep. Dilute 1 part sodium hypochlorite (household bleach, for example, Clorox®) to 10 parts water as a disinfectant.
Cattle with ringworm may infect sheep if they are comingled. Avoid this when possible.
Mineral mixes containing EDDI (organic iodine salt) may increase an animal’s resistance to ringworm.
Wear gloves when handling sheep affected with ringworm.
(3) Treatments
Most cases of “Club Lamb Fungus” will heal without treatment within 1-4 months.
Treatment of a lamb with ringworm lesions will not allow it to enter the fair. An animal with lesions that are visible and obviously not healed will be denied entry.
Many treatments have been tried but none is foolproof or always effective. Before treating lesions they should be clipped including a two inch margin of good wool around them, remembering that the clippings are infective and should be burned or discarded carefully off the farm. Be sure to disinfect the clippers and blades very well. Always wear gloves. Because fungi are hard to kill, in general treatments should be given once a day for 5 days and then weekly for 3 additional applications.
Treat an entire infected lamb with .5% chlorhexidine (Nolvasan®) made by adding 3 ounces to a gallon of water. Spray or dip the entire animal; a sponge works well to wet the face. This is the same solution recommended in the “prevention” section above.
A mixture of 1 part strong (7%) tincture of iodine mixed with 3 parts baby oil has been recommended to apply to lesions to help dry them up. Tamed iodine solutions (povidone- iodine, for example Betadine solution) directly applied to lesions has also been used. Iodine treatments may stain the wool.
.5% lime sulfur solution has been recommended; however, it has a rotten egg odor and stains wool.
See”Other information & references” below for more information and suggestions.
(4) Other information & references
California Department of Food and Agriculture (January 2009). Club Lamb Fungus (Ringworm).
http://www.cdfa.ca.gov/AHFSS/Animal_Health/pdfs/Club_lamb_fungus_disease.pdf
Currin, Nancy and Pelzer, Kevin. Club Lamb Fungus. Virginia Cooperative Extension.
http://pubs.ext.vt.edu/410/410-018/410-018.html
Hopkins, Fred M. and Gill, Warren. Ringworm (Club Lamb Fungus)in Sheep. University of Tennessee.
http://animalscience.ag.utk.edu/sheep/pdf/Ringworm.pdf
Maryland Small Ruminant Page. Skin Diseases.
http://www.sheepandgoat.com/skin.html
B. Soremouth (Contagious Ecthyma, also known as Orf)
(1) Description
The formal medical name for Soremouth is Contagious Ecthyma though the condition is sometimes referred to by its older common name of Orf. It is caused by a readily contagious poxvirus that commonly infects sheep and goats. Goats typically develop more serious lesions than sheep. One recent survey reported that 40% of sheep and goat farms in the U.S. had soremouth in their flocks in the three years prior.
Sores on the lips, muzzle, gums and mouth appear when an animal is first infected. These sores are painful ,especially when they first appear, but usually heal within 4-5 weeks. Lesions may become infected with bacteria causing secondary infections or infested with maggots. Secondary bacterial infections or maggot infestations complicate recovery and may result in fatalitiesin animals that are weak from not eating because of mouth pain. The disease is usually more severe in young animals because they have no immunity against it. Infection causes the animal’s immune system to be resistant to subsequent infections such that infected older animals usually have less severe disease. Animals can be carriers of the virus without developing sores.
Some nursing ewes or does develop sores on their teats and lower legs as nursing lambs or kids spread the infection. Young animals often have difficulty nursing and lose condition while some nursing mothers show signs of lameness and, in more severe cases, abandon their young because of painful teat sores.
Uninfected animals can contract the disease from direct contact with infected animals. The initial lesions will develop into scabs as healing occurs and can serve as vehicles of infection for other animals. The pox virus in dried scabs can remain infective for years in the environment such as in bedding, equipment, or feed troughs. One source reports the virus has been recovered from dried crusts in the environment after 12 years. Therefore, once a flock or herd and its environment are infected, it is very difficult to clean up.
Because soremouth lesions resemble those seen with some very serious “Foreign Animal Diseases” that do not occur in the U.S., such as Foot and Mouth Disease, it is important to obtain an early diagnosis from a veterinarian, especially if soremouth has not previously occurred in a flock.
Soremouth is a zoonotic disease. People can become infected by contact with infected sheep and goats or equipment and also potentially from handling the orf vaccine (see below) which is a modified live virus. Human lesions usually develop on the hands arms, and face causing sores which may be painful and take weeks to heal although the disease is not usually serious in most people with good immune systems. Humans who have immune system diseases, organ transplants, or are taking drugs to suppress the immune system (corticosteroids) or cancer chemotherapy should consider avoiding contact with sheep or goats infected with soremouth. Lesions in these people may be more severe and difficult to heal. There is no effective treatment for humans infected with orf other than dressing the sores to prevent spread. Consult a physician if orf is suspected in humans, particularly if a lesion is growing in size or spreading.
Soremouth Image A
Soremouth Image B
(2) Prevention
Isolate new additions until sure that they are not infected with the soremouth virus. DO NOT TAKE ANIMALS WITH SOREMOUTH TO FAIRS, SHOWS AND EXHIBITS. Animals returning from fairs where there was potential for contact with infected animals or environments should be isolated once returning to the farm of origin.
There are commercial vaccines available which contain modified live virus. Consult a veterinarian before using the vaccine and follow label directions carefully. If a flock is not infected it may not be recommended to vaccinate since using it will introduce the virus onto the farm. This may result in soremouth lesions where they were not seen before and seeding the environment with infected scabs. Some producers vaccinate all breeding replacement animals which are brought onto a farm. Vaccinating all nursing lambs and kids in each year’s crop may be recommended in infected flocks. The vaccine will typically cause reddening and swelling at the site of administration, followed by a scab which will fall off. This type reaction to the vaccine shows the vaccine worked effectively. It may be recommended to booster the vaccination with a second dose 2-3 months later depending on the level of severity of infection.
People should wear rubber or latex gloves when handling sheep and goats infected with soremouth, particularly if examining sores in the mouth and when handling orf vaccine.
(3) Treatments
Lesions with secondary bacterial infections can be treated with topical antibiotics, and in more advanced cases injectable antibiotics may be needed. Consult a veterinarian for advice on how to treat individual animals and herds/flocks. Fly control may reduce maggot infestation of lesions, as may direct applications of fly repellants or insecticides on lesions.
(4) Other information & references
Alabama Cooperative Extension System. Contagious Ecthyma (Orf/Sore Mouth) in Sheep and Goats.
http://www.aces.edu/pubs/docs/U/UNP-0063/
Centers for Disease Control. Sore Mouth Infection. Orf Virus Infection.
http://www.cdc.gov/ncidod/dvrd/orf_virus/
Hartwig, Nolan. Iowa State University Extension. Contagious Ecthyma (Sore Mouth).
http://www.extension.iastate.edu/Publications/PM829X1.pdf
Schoenian, Susan. University of Maryland Extension. Soremouth (orf) in sheep and goats.
http://www.sheepandgoat.com/articles/soremouth.html
Although there are reports of warts in sheep caused by a papillomavirus, they are unusual and not among the conditions which would be most likely to cause a sheep to be denied entry to a fair. “Soremouth” (See above discussion, III B.) lesions are very common in sheep and have a wart-like appearance, causing this condition sometimes to be referred to as “warts.” Because such lesions in sheep are most likely to be Soremouth, any wart-like lesion will usually cause an animal to be denied entry to a fair.
For information on warts in cattle see section I B. above.
Because some many conditions can cause diarrhea which are infectious and contagious in nature, in most cases sheep showing clinical signs will not be allowed into a fair. Animals with diarrhea will contaminate the surrounding environment including bedding, feed, flooring, and water troughs, potentially exposing large numbers of other animals in close quarters in a livestock exhibition facility. Although many animals with infections causing diarrhea may have a fever, the absence of a fever cannot rule out an infectious cause which could be contagious to other animals. Therefore, an animal with diarrhea will likely be denied entry to a fair even if it does not have an elevated body temperature as determined by a rectal thermometer.
For information on diarrhea in cattle see section I D. above.
E. Pneumonia/Respiratory Disease
As with diarrhea, pneumonia or respiratory disease in sheep can be caused by a number of different infectious agents including viruses, bacteria, and occasionally even parasites. Most of these causes are contagious. Since the causes of respiratory disease are many and varied and the clinical signs can vary widely, it is best described as a “respiratory disease complex.” Sheep showing clinical signs of respiratory disease such as coughing, nasal discharge (“snotty nose”), rapid breathing, and an elevated rectal temperature will be denied entry to a fair.
Promptly examine any animal showing signs of respiratory disease. Animals with an elevated rectal temperature and clinical signs conisistent with respiratory disease should be treated with an injectable antibiotic approved for treatment of the major infectious agents causing respiratory disease, and treatments should repeated for an appropriate number of times to insure there is no relapse. Many times treatments are not continued long enough and the disease is not eliminated. Consult your veterinarian on which antibiotics to use, the dosage for the weight of animal involved, and the number of treatments and time between each in such cases. Always remember the pre-slaughter withdrawal times after using any drug in livestock.
For a more complete discussion see section I E. above on respiratory disease in cattle.
F. Abscesses (Caseous Lymphadenitis)
(1) Description
Penetrating skin wounds in sheep and goats often result in infections under the skin or internal organs by a bacterium, Corynebacterium pseudotuberculosis. In sheep and goats these infections tend to form abscesses or collections of pus under the skin and in the superficial lymph nodes just under the skin. In sheep the lymph nodes in front of the shoulder (pre-scapular) and rear leg (pre-femoral) are the primary ones which tend to abscess. The abscesses can dry up and organize into hardened areas, but often they are thick and pasty. Other bacteria can also cause abscesses in sheep but C. pseudotuberculosis is the primary one causing problems. The organism can also localize in the animal’s internal organs such as the kidneys or lymph nodes in the GI tract. Such internal abscesses can cause an animal to lose condition and become very thin and emaciated even when adequate nutrition is available.
Equipment used in shearing or management that may penetrate the skin of an animal is often the source of infection in a flock or herd. Sheep or goats with abscesses that rupture will seed the environment with the bacteria which can remain alive and infectious for months.
Abscess Sheep: Image 1
Abscess Sheep: Image 2
Abscess Goat: Image 1
(2) Prevention
Do not allow sheep or goats with clinical signs of abscesses under the skin or in the superficial lymph nodes to come into a flock. Cull any obviously affected animals once abscesses are detected. If valuable animals that have abscesses must be kept in a flock they should be segregated from unaffected animals. There is a blood test available to detect infected animals which do not have clinical signs of abscesses. Such testing may be useful in a flock where the owner is trying to eliminate the infection. This test does have some false positive results, so results must be interpreted carefully. A commercial vaccine, which can raise resistance to abscessation in unaffected animals, is available but it is not totally effective in preventing infection and does not cure animals which are already infected. Institute a program for thorough cleaning and disinfection of shearing blades and other equipment that can serve as sources of infection in an infected flock.
(3) Treatments
Abscesses can be lanced and flushed with iodine solution but care should be taken to prevent environmental contamination with pus. Such treated areas frequently abscess again after a period of time so culling these animals is a sounder course of action. The primary organism is usually susceptible to antibiotics such as penicillin but because the abscesses are difficult to penetrate, such treatments are not effective in eliminating the infection in an individual or a flock and are not generally recommended.
(4) Other information & references
Alabama Cooperative Extension System. Caseous Lymphadenitits (CL) in Sheep and Goats.
http://www.aces.edu/pubs/docs/U/UNP-0085/
Merck Veterinary Manual. Caseous Lymphadenitis of Sheep and Goats.
http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/10801.htm&word=sheep%2cabscess
Powell, J. University of Arkansas Cooperative Extension Service. Caseous Lymphadenitis in Small Ruminants.
http://www.uaex.edu/Other_Areas/publications/PDF/FSA-3095.pdf
III. Goats
This condition occurs in show goats although it is more commonly associated with show sheep. For a complete discussion of the condition in sheep, see section III A. above, “Ringworm – Club Lamb Fungus.” Goats showing signs of ringworm will likely be denied entry to a fair.
B. “Soremouth” (also known as “Orf” or Contagious Ecthyma)
Soremouth affects both sheep and goats, although some have observed it to be a more severe disease in goats than in sheep. For a complete discussion of the disease see section III B. above.
There are reports of warts in goats, possibly caused by a papillomavirus, however they are relatively unusual and not among the conditions which would be expected to cause a goat to be denied entry to a fair. “Soremouth” (See above discussion, III B.) lesions are common in goats and have a wart-like appearance, causing this condition sometimes to be referred to as “warts.” Because such lesions in goats, particularly if they are on the mouth, are likely to be Soremouth and, thus, highly contagious, any wart-like lesion will usually cause an animal to be denied entry to a fair.
For information on warts in cattle see section I B. above.
Because many conditions thatcause diarrhea are infectious and contagious in nature, goats showing clinical signs, in most cases, will not be allowed into a fair. Animals with diarrhea will contaminate the surrounding environment including bedding, feed, flooring, and water troughs, potentially exposing large numbers of other animals in close quarters in a livestock exhibition facility. Although many animals with infections causing diarrhea may have a fever, the absence of a fever cannot rule out an infectious cause which could be contagious to other animals. Therefore, an animal with diarrhea will likely be denied entry to a fair even if it does not have an elevated body temperature as determined by a rectal thermometer.
For information on diarrhea in cattle see section I D. above.
E. Pneumonia/Respiratory Disease
As with diarrhea, pneumonia or respiratory disease in goats can be caused by a number of different infectious agents including viruses, bacteria, and occasionally even parasites. Most of these causes are contagious. Since the causes of respiratory disease are many and varied and the clinical signs can vary widely, it is best described as a “respiratory disease complex.” Goats showing clinical signs of respiratory disease such as coughing, nasal discharge (“snotty nose”), rapid breathing, and an elevated rectal temperature will be denied entry to a fair.
Promptly examine any animal showing signs of respiratory disease. Animals with an elevated rectal temperature and clinical sigsns conisistent with respiratory disease should be treated with an injectable antibiotic approved for treatment of the major infectious agents causing respiratory disease, and treatments should repeated for an appropriate number of times to insure there is no relapse. Many times treatments are not continued long enough and the disease is not eliminated. Consult your veterinarian on which antibiotics to use, the dosage for the weight of animal involved, and the number of treatments and time between each in such cases. Always remember the pre-slaughter withdrawal times after using any drug in livestock.
For a more complete discussion see section I E. above on respiratory disease in cattle.
F. Abscesses (Caseous Lymphadenitis)
See section III F. above.
IV. Pigs
A. Ringworm
Spores of fungi (plural of fungus) in the soil may cause skin lesions in pigs as they do in other animals including cattle, sheep and goats. A Microsporum fungus is often the cause in swine although there can be several others. Spores which come in contact with skin of pigs will germinate and grow into hair shafts. The typical lesions in pigs are round, often colored brown and reaching a circular diameter of 6 centimeters. This condition is usually not of much economic importance other than as blemishes which may call the quality of purebred or breeding pigs into question at sale. Pigs showing signs of the disease are contagious to other pigs. Ringworm in swine can be a zoonotic disease which spreads to humans. In show pigs treatments similar to those in cattle have been attempted (see section II A above), but because it is infectious and contagious, pigs showing clinical signs of ringworm will likely be denied entry to a fair.
Ringworm
(1) Description
Mange in pigs is caused by a microscopic parasitic mite named Sarcoptes scabeii var suis. The mites are transmitted from infected pigs introduced into a herd, making it a contagious disease which will cause a pig to be denied entry to a fair. The primary means of transmission is pig-to-pig, although the mites will survive for a while in bedding and the environment. The first sign of mange in pigs is usually on the head and ears, then spreading to the rest of the body. Mange causes intense itching in the pig thereby reducing growth and feed efficiency compared to uninfected pigs. The itching is caused by an allergic reaction to the mites which burrow in the pig’s skin. The skin becomes thickened and crusty over time.
Pig Mange: Image 1
Pig Mange: Image 2
Pig Mange: Image 3
(2) Prevention
Do not allow infected pigs onto a farm, or pigs from a farm which has been infected with mange. Aggressively treat or cull affected pigs as soon as they are detected.
(3) Treatments
Various topical sprays are effective as is injectable ivermectin. See “Other information & references” below for more detailed information.
(4) Other information & references
Merck Veterinary Manual. Mange in Pigs.
http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/72004.htm&word=mange%2cpigs
Because many conditions that cause diarrhea are infectious and contagious in nature, in most cases pigs showing clinical signs will not be allowed into a fair. Animals with diarrhea will contaminate the surrounding environment including bedding, feed, flooring, and water troughs, potentially exposing large numbers of other animals in close quarters in a livestock exhibition facility. Although many animals with infections causing diarrhea may have a fever, the absence of a fever cannot rule out an infectious cause which could be contagious to other animals. Therefore, an animal with diarrhea will likely be denied entry to a fair even if it does not have an elevated body temperature as determined by a rectal thermometer.
Reference:
Merck Veterinary Manual. Intestinal Diseases in Pigs: Introduction.
http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/22300.htm&word=diarrhea%2cpigs
D. Pneumonia/Respiratory Disease
As with diarrhea, pneumonia or respiratory disease in pigs can be caused by a wide variety of infectious agents including viruses and bacteria. Most of these causes are very contagious. Since the causes of respiratory disease are many and varied and the clinical signs can vary widely, it is best described as a “respiratory disease complex.” Pigs showing clinical signs of respiratory disease such as coughing, nasal discharge (“snotty nose”), rapid breathing, and an elevated rectal temperature will be denied entry to a fair.
Promptly examine any animal showing signs of respiratory disease. Animals with an elevated rectal temperature and clinical signs of respiratory disease should be treated with an injectable antibiotic approved for treatment of the major infectious agents causing respiratory disease, and treatments should repeated for an appropriate number of times to insure there is no relapse. Many times treatments are not continued long enough and the disease is not eliminated. Consult your veterinarian on which antibiotics to use, the dosage for the weight of animal involved, and the number of treatments and time between each in such cases. Always remember the pre-slaughter withdrawal times after using any drug in livestock.
Merck Veterinary Manual. Respiratory Diseases of Pigs: Introduction.
http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/121400.htm