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This is an excerpt of Dairy Goat and Sheep Operations in the Southeast Production Guide, ANR-2457.

Abortion

Many things, including toxic agents, congenital abnormalities, and infectious diseases, can cause abortions. The most common infectious microorganisms that cause abortions in goats and sheep are the following:

  • chlamydiosis (Chlamydia psittaci)
  • query or Queensland (Q) fever (Coxiella burnetii)
  • listeriosis (Listeria monocytogenes)
  • leptospirosis (Leptospira spp)
  • toxoplasmosis (Toxoplasma gondii)
  • brucellosis (Brucella melitensis)
  • neosporosi (Neospora caninum)
  • mycoplasma sp
  • vibriosis of campylobacteriosis (Campylobacter fetus ssp intestinalis)

Many of the infectious causes of abortion in goats and sheep are zoonotic, meaning they can also cause disease in humans. The use of protective clothing and latex gloves or plastic arm sleeves is recommended anytime aborted tissues are handled or assistance is provided during kidding or lambing.

Diagnosis is based on history of the herd/flock and clinical signs. Aborted fetuses and fresh placenta should be packed on ice, marked with correct identification of the doe/ewe, and sent to a diagnostic laboratory for identification of the infectious agent.

Treatment and prevention depends on the cause of abortion.

Follow these guidelines when abortion occurs on your goat or sheep dairy:

  • Inform your veterinarian immediately for help conducting a thorough investigation.
  • Wear protective clothing and latex gloves or plastic sleeves to prevent zoonotic infection. Incinerate the gloves afterward to prevent environmental contamination.
  • Isolate the animal from the herd and keep it in a quarantine pen for further examination.
  • Collect the placenta and fetus and keep them refrigerated or on ice. Do not freeze. Your veterinarian may want to examine these tissues and send them to a diagnostic laboratory for isolation and identification of the infectious agent.

Bacterial Pneumonia

The most frequent causes of respiratory infection and death of dairy goats and sheep are Pasteurella multocida or Mannheimia haemolytica (previously called Pasteurella haemolytica). These bacteria are commonly found in the upper respiratory tract of healthy animals.

Signs of pneumonia include the following:

  • fever with temperature of 104 degrees F (40 degrees C) to 106 degrees F (41 degrees C)
  • moist, painful cough and dyspnea (difficulty in breathing), along with nasal and ocular mucopurulent discharge. Listening to the lungs with a stethoscope may reveal crackling sounds.
  • anorexia or loss of appetite
  • lethargy

Diagnosis is based on clinical signs and herd history. If the animal dies, a necropsy may help to identify the exact cause of the pneumonia.

Treatment involves antibiotic therapy as prescribed by your veterinarian. Keep sick animals in a dry, well-ventilated location away from the rest of the herd.

Prevention and control involves vaccination and proper herd management.

Caprine Arthritis Encephalitis (CAE)

Caprine arthritis encephalitis is caused by a virus classified as a small ruminant lentivirus (SRLV) of the family Retroviridae. The virus negatively impacts the well-being of infected animals and the economy of the goat and sheep industry in many countries of the world, including the United States. CAE is primarily prevalent in dairy goat breeds but has been diagnosed in meat goats and sheep as well.

The primary mode of transmission for CAE is through the consumption of colostrum and milk from infected does/ewes. Blood from open wounds or on contaminated instruments, such as needles, dehorners, etc., is regarded as the second most common mode of transmission. Contact transmission between adult goats is considered to be rare, except during lactation.

CAE normally displays a slow, chronic progression over months or years. Some signs of CAE include chronic polyarthritis (inflammation of the joints), mastitis, and interstitial pneumonia.

Paralysis due to the encephalitis and myelitis (inflammation of central nervous system) tends to be more common in kids between 2 and 6 months of age.

Diagnosis is based on herd health history and laboratory tests, such as ELISA (enzyme-linked immunosorbent assay).

There is no cure for CAE. Treatment consists of supportive therapy. Prognosis for the encephalitic form is poor. Infected animals that recover will carry the virus for life.

Prevention and control includes the following:

  • Cull CAE-positive animals from the herd.
  • Avoid purchasing breeding stock from an unknown source.
  • Test existing stock and new animals for CAE before introducing them to the herd.
  • Remove kids born of CAE-positive does from their mothers immediately at birth. Feed them heat-treated colostrum and pasteurized milk until weaning.
  • Maintain a closed herd.

Caseous Lymphadenitis (CL)

The bacteria Corynebacterium pseudotuberculosis causes CL and is prevalent in all countries throughout the world, including the United States. Goats and sheep are infected by contact with the pus of an infected animal or ingestion of feed and water contaminated by Corynebacterium pseudotuberculosis.

Signs of CL include external and internal abscesses. CL abscesses typically contain pasty, thick, yellow-green pus with a foul odor.

Diagnosis is based on clinical signs detected by physical examination. The CL abscesses range from firm to soft swelling, and some are well-defined with rounded shapes on the surface of the animal’s body. Blood tests are also available.

There is no cure for caseous lymphadenitis. Abscesses are sometimes carefully drained to prevent ruptures and further contamination of healthy animals and premises.

Prevention and control includes the following:

  • Cull infected animals from the herd to help reduce the risk of CL infection.
  • Avoid purchasing animals from farms with a history of CL, and do not purchase animals with visible abscesses or abscess scars.
  • Examine males before introducing them to the female herd. A male with erupted abscesses can contaminate the females.
  • Use a clean needle with each animal to prevent the spread of C. pseudotuberculosis from asymptomatic carriers to noninfected animals.
  • Always disinfect equipment, such as ear taggers, tattooing needles, hoof trimmers, or wool shears, that might break the skin of animals when used. Shearing equipment is of special concern, as a hidden abscess might be ruptured during shearing.
  • Consider maintaining a closed herd.

Coccidiosis

Coccidiosis is a costly parasitic livestock disease affecting goats and sheep. Eimeria species, also called coccidian species, are protozoa naturally found in the soil that cause coccidiosis. Coccidia are host-specific, meaning the species of coccidia that affect one species of animals is different than the species that affects another. For example, the coccidia that affect chickens are different than the coccidia that affect goats.

Ingesting oocytes when grazing can infect goats and sheep, as can drinking water contaminated with goat or sheep feces. Once ingested, oocytes penetrate the cells lining the intestine causing inflammation and destruction of intestinal cells.

Stress is a predisposing factor in kids/lambs during the post- weaning period. Animals may die suddenly during this phase without any warning. Outbreaks can occur during stressful conditions, such as after shipping or farm relocation.

Symptoms of coccidiosis include the following:

  • watery diarrhea with or without mucus or blood
  • constipation
  • lack of appetite accompanied by fever
  • dehydration as a result of diarrhea
  • weakness
  • emaciation caused by weight loss
  • sudden death
  • hemorrhaging or ulcerations in the intestinal wall

Diagnosis is based on herd health history, clinical signs, and microscopic fecal examination.

Treatment options include drenching with a coccidiostat recommended by your veterinarian, or administering the coccidiostat in the drinking water. In cases involving severely dehydrated animals, intravenous (IV) fluid therapy may be needed until the animal is rehydrated.

Prevention and control includes the following:

  • Improve management and hygiene of facilities, pastures, pens, and feeding and water sources.
  • Minimize weaning stress. If needed, creep feed to adjust the kids to a new diet prior to weaning.
  • Ask your veterinarian about using a medicated feed containing a coccidiostat, such as monensin, lasalocid, or decoquinate.
  • Avoid keeping animals in moist areas without direct sunlight.
  • Anticipate possible outbreaks during severe weather and post-weaning.

Contagious Ecthyma (Orf/Sore Mouth)

Orf is caused by a parapoxvirus. This is also a zoonotic disease, which means that it is easily transmitted from animals to humans. Goats and sheep contract sore mouth by direct contact with the virus.

Susceptible animals usually develop the first signs of the disease 2 to 5 days after exposure, and symptoms typically persist for 1 to 2 weeks. Outbreaks of sore mouth are most frequent following stressful events, such as weaning, transportation, or relocation.

The primary symptom is blisters that develop into wet scabs on the lips, nose, ears, or eyelids. Nursing kids/lambs can transmit the virus to their dam, resulting in lesions on the teats and udder. The lesions can be extremely painful to the point of preventing sick animals from eating.

Initial diagnosis is based on the characteristics and location of the lesions. A definitive diagnosis is based on virus isolation and an immunologic test.

Contagious ecthyma usually resolves on its own without treatment. In severe cases, the use of antibiotics may be recommended by your veterinarian to combat secondary bacterial infections.

Prevention and control includes the following:

  • Minimize transportation stress.
  • Always quarantine new animals for 6 weeks before introducing them to the rest of the herd.
  • Separate sick animals in a pen for treatment and observation in the case of an outbreak.
  • Always feed and treat sick animals after feeding the rest of the herd.
  • Always wear gloves when handling infected animals.
  • Avoid the consumption of milk from does/ewes that present lesions on the teats and udder.
  • Vaccinate only in certain situations following specific guidelines from your veterinarian.
  • Isolate recently vaccinated animals from unvaccinated animals. Since the vaccine contains a modified live virus, humans should use care when administering the vaccine to avoid the risk of infecting themselves.

Enterotoxemia (Overeating Disease)

Enterotoxemia, also known as overeating or pulpy kidney disease, is a condition caused by the absorption of a large amount of toxins produced by Clostridium perfringens types C and D in the intestines.

These bacteria are found in the soil and as part of the normal microflora in the gastrointestinal tract of a healthy goats and sheep. Under certain conditions, these bacteria can rapidly reproduce in the animals, producing large quantities of toxins.

Symptoms most frequently occur in young kids/lambs and include the following:

  • loss of appetite
  • abdominal discomfort, shown by kicking at the belly and arching the back
  • profuse diarrhea with or without blood
  • fever
  • lethargy
  • sudden death

Diagnosis is based on clinical signs and history of sudden death that can be confirmed by necropsy.

Treatment includes the following:

  • Administer C and D antitoxin according to the manufacturer’s recommendation. Kids are normally treated with 5 mL of C and D antitoxin subcutaneously.
  • Administer penicillin.
  • Administer an oral antacid.
  • Administer anti-bloating medication.
  • Reduce pain by administering an anti-inflammatory, such as flunixin meglumine (as prescribed by a veterinarian).
  • Administer thiamin (vitamin B1) intramuscularly.
  • Replace fluids intravenously.
  • Administer probiotics after treatment with antibiotics to encourage repopulation of the microflora in the rumen and intestinal tract.

Vaccination of all animals in the herd against Clostridium perfringens types C and D is generally effective in preventing enterotoxemia.

Foot Rot and Foot Scald

Foot rot is a contagious disease of the hooves of goats and sheep. It is primarily caused by Dichelobacter nodosus and Fusobacterium necrophorum that can be found in the feces of goats and sheep and in contaminated soil.

Foot scald or interdigital dermatitis, is an inflammation between the toes caused by F. necrophorum. Outbreaks occur most often during a persistent rainy season with high temperatures, when animals walk across wet pastures and muddy soil. If not treated, animals can become permanently infected.

The signs of foot rot include limping, holding limbs above the ground, grazing on knees, reluctance to walk, pus and a foul odor with hoof deformity, and loss of appetite. Goats and sheep with chronic foot rot show loss of body condition, infertility, and decreased production of milk. Foot scald is characterized by interdigital inflammation. The skin between the toes is pink to white in color, raw, moist, and very sensitive to the touch.

Treatment includes the following:

  • Isolate affected animals for treatment and trim hooves.
  • Treat the feet with a footbath solution of 16 percent copper sulfate or zinc sulfate. Animals must stand in the zinc or copper sulfate solution to allow time for absorption into the hoof wall. Lameness is generally resolved within a couple of days after treatment.
  • Administer antibiotic therapy if recommended by your veterinarian.
  • Keep treated animals in a dry environment for 24 hours after treatment. Hooves should be trimmed as needed to expose the infected tissue to oxygen.
  • Maintain clean pens and barns.

Prevention and control includes the following:

  • Cull highly susceptible animals and enhance selective breeding for resistance to foot rot.
  • Trim hooves as needed.
  • Check animals for foot lesions before purchasing.
  • Quarantine new animals for 6 weeks after they arrive at the farm.
  • Give animals a footbath upon purchasing and returning from shows, and prior to their re-entry or entry into the herd.
  • Vaccinate sheep as a preventative tool for foot rot. The United States Food and Drug Administration (FDA) does not approve this vaccine for use in goats.

Haemonchosis

Haemonchosis caused by Haemonchus contortus, also known as the barber pole worm, is the number one health threat to goats and sheep worldwide. Haemonchus contortus is a nematode parasite that causes anemia, diarrhea, dehydration, lower growth rates, markedly reduced reproductive performance, and higher rates of illness and death.

Goats and sheep become infected upon ingesting infective larvae while grazing. The larvae burrow into the mucosal (internal layer) of the stomach and begin feeding on the red blood cells of the animal within a few hours.

Symptoms of haemonchosis include the following:

  • diarrhea
  • dehydration
  • anemia
  • white mucous membranes
  • rough hair coat, lethargy, and incoordination
  • fluid accumulation in submandibular tissues (bottle jaw), abdomen, thoracic cavity, and gut wall
  • significantly reduced growth and reproductive performance

Diagnosis is based on microscopic fecal examination. Anemia (reduction of red blood cells) can be easily detected using the FAMACHA system by examining the color of the goat’s lower eyelids and comparing it to a color-coded chart. These two methods are complementary and can be incorporated in the farm management as a tool to identify parasite drug resistance and to select for resilience.

Treatment involves use of commercially available anthelminthics. Treatment should be limited to animals with higher worm burdens. Alternative methods of prevention and control must be considered to mitigate parasite drug resistance.

Prevention and control includes the following:

  • Purchase animals from known sources.
  • Keep stocking rates low.
  • Cull highly susceptible animals in herds and flocks.
  • Check breeding stock prior to breeding, kidding, and weaning to identify animals that need to be treated or culled.
  • Provide clean water and adequate minerals.
  • Use gravel or concrete in feedlot areas to break the worm life cycle and to prevent reinfestation.
  • Consider pasture rotation.
  • Provide high-quality hay and feed off of the ground to avoid contamination by feces.
  • Incorporate browse plant species to goat herds when possible.
  • Try a mixed-species grazing program using cattle and goats.
  • Alternate the pasture with a short-cycle crop, such as chicory, when possible.
  • Incorporate plants with anthelmintic properties, including plants rich in condensed tannin (such as Sericea lespedeza), in the diet of dairy goats and sheep. These can be made available for grazing as hay or as pellets.
  • Select animals for worm resistance or resilience.

Johne’s Disease (Paratuberculosis)

Johne’s disease is a chronic enteritis (inflammation of the intestine) of ruminants caused by the bacteria Mycobacterium avium subspecies paratuberculosis (MAP). MAP can infect goats, sheep, cattle, bison, rabbits, deer, and other wild animals though fecal contamination of feed and water.

Johne’s disease is a chronic condition that can be dormant for years without causing any symptoms. Infected goats and sheep may contaminate pastures for years before showing any clinical signs of the disease.

As Johne’s disease progresses, infected animals show progressive weight loss (despite a good appetite), bottle jaw, lethargy, diarrhea in some cases, decreased milk production, enlargement of regional lymph nodes, and death.

Diagnosis can be difficult. It is most effectively diagnosed based on a combination of herd health history and diagnostic tests, such as ELISA and/or fecal culture and PCR.

There is no effective treatment for Johne’s disease. There is no vaccine available. The best prevention and control is to test existing breeding stock and suspicious animals in the herd. Cull positive animals and avoid purchasing breeding stock from unknown sources.

For more information about prevention and control of Johne’s disease, visit the American Dairy Goat Association website at http:// adga.org/johnes-disease or the Johne’s Information Center at https:// johnes.org/goats/diagnosis.html.

Keratoconjunctivitis (Pinkeye)

In goats and sheep, the microorganisms Mycoplasma conjunctivae and chlamydia species primarily cause pinkeye. Outbreaks frequently occur when new animals are introduced to the herd, are transported or relocated, or when animals are experiencing severe stress in harsh weather. Infection can be easily disseminated in the herd by contact with sick animals.

Symptoms include the following:

  • squinting
  • watery, red, swollen eyes
  • cloudiness in normally clear parts of the eyes
  • wound-like ulcers in the eyes in severe cases
  • yellow or green pus draining from the eyes and drying into crusts

Pinkeye can cause temporary blindness, weight loss, and decreased performance. Severe untreated cases can result in permanent blindness.

Diagnosis is based on clinical signs and by culture or isolation of the microorganisms from eye secretions. Swabs from infected animals should be sent to a diagnostic laboratory for isolation and identification of a causative agent.

Treatment includes the following:

  • Immediately isolate sick animals from the herd.
  • Flush eyes with sterile saline.
  • Contact your veterinarian immediately. Antibiotics prescribed by your veterinarian can be very effective in treating pinkeye in goats and sheep when used early in the course of the disease.
  • Prevent contamination of the entire herd by feeding and treating sick animals after feeding healthy animals.
  • Always wear latex gloves when treating sick animals. Provide clear water and good feed to sick animals. Sick animals can be temporarily blinded and may not be able to easily reach food and water.
  • Control flies to prevent the disease from spreading.
  • Consult your veterinarian for product usage and appropriate milk and meat withdrawal periods.

Prevention and control includes the following:

  • Examine animals for pinkeye prior to purchase.
  • Minimize transportation stress.
  • Quarantine newly purchased animals to avoid the possibility of introducing sick animals into the herd.
  • Control flies.

Listeriosis (Circling Disease)

Listeriosis is a life-threatening disease of goats and sheep caused by the bacteria Listeria monocytogenes. Goats and sheep are infected by ingestion of spoiled forages and feed contaminated by L. monocytogenes.

The encephalitic form (inflammation of the brain) has a high mortality rate. Infected goats and sheep show progressive neuromuscular incoordination; animals circle in the same direction and experience seizures, facial nerve paralysis (usually on one side), ear droop, salivation, impaired swallowing, and death. The septicemic form occurs less frequently in goats and sheep, but it involves diarrhea, abortion, and death.

Diagnosis is based on clinical signs. Treatment involves antibiotics, anti-inflammatories, and supportive therapy such as administration of intravenous fluid and electrolytes.

To help prevent listeriosis, discard spoiled feed and hay. In the case of abortion, isolate aborting does/ewes and send aborted fetuses and placentas to a diagnostic laboratory for isolation of the causative agent.

Mycoplasmosis

Mycoplasmosis, also known as contagious agalactiae (CA), is one of the most costly diseases for the dairy goat and sheep industry. It is caused by any of the following four agents: Mycoplasma agalactiae, M. mycoides subspecies capri, M. capricolum subspecies capricolum, and M. putrefaciens.

Herds and flocks become infected through the introduction of a carrier animal. Once established in a herd/flock, young kids/ lambs become infected while suckling. Adult animals are infected via milker’s hands, milking machines, or possibly by bedding. Other routes of transmission may include aerosols of infective exudates over short distances, and ingestion of contaminated water.

Asymptomatic carriers can exist and make control efforts difficult.

The three major symptoms of CA are mastitis, arthritis, and keratoconjunctivitis. Infected goats and sheep can have severe lameness as a result of the polyarthritis, hot swollen joints, weight loss, and fever.

Some animals develop diarrhea and increased respiratory rates. Adult does/ewes may have mastitis, cough and shortness of breath, runny nose, loss of appetite, weakness, keratoconjunctivitis, and abortion. Infected herd morbidity can reach up to 90 percent and mortality up to 30 percent.

Initial diagnosis is based on herd health history and confirmed via laboratory tests, such as culture and isolation of mycoplasma from the milk of infected does/ewes, ELISA, and PCR.

Treatment measures include supportive therapy as well as culling infected animals and systematically pasteurizing the milk fed to kids/ lambs. Veterinarians also may prescribe antibiotics. The prognosis for complete recovery, however, is guarded.

Prevention and control includes the following:

  • Avoid purchasing breeding stock from an unknown source.
  • Test recently purchased animals for mycoplasma before introducing them to the herd, and cull positive animals.
  • Test milk for mycoplasma and cull positive animals.
  • In infected herds, separate kids/lambs from the mother soon after birth. Feed colostrum from healthy does/ewes and pasteurized milk or milk replacer.
  • Improve hygienic conditions in the milking parlor and sanitize milking machines.
  • Keep kids/lambs separated from adults.
  • Keep a closed herd.
  • Apply biosecurity measures.

Polioencephalomalacia (Deficiency of Thiamine/Vitamin B1)

Polioencephalomalacia (PEM), commonly referred to in livestock as polio, is a common metabolic disorder characterized by neuromuscular alterations of goats and sheep that are thiamine deficient. Despite the name, this is an entirely different condition than human polio. Adults and young animals are equally at high risk for developing the disorder.

Polio is usually seen in animals that are under higher nutritional management conditions, such as feedlots, animals on lush pasture supplemented with highly concentrated rations, animals under stress or on prolonged treatment with amprolium, or those who experience sudden dietary changes.

Symptoms include the following:

  • convulsions that can occur in 2- to 5-minute intervals
  • dullness and lethargy
  • incoordination
  • increased aggression
  • muscle tremors or contractions
  • temporary blindness that can last 2 to 3 weeks
  • increased body temperature, pulse, and respiration rates
  • opisthotonos (abnormal posturing where the head is thrown backward accompanied by rigidity)
  • severe arching of the back
  • teeth grinding
  • nystagmus (rapid involuntary movement of the eyeballs)
  • death

Diagnosis is based on clinical signs, herd management, and laboratory analysis. Animals that are treated early in the course of the disease will show improvement within minutes to a few hours following a slow intravenous administration of thiamine. Contact your veterinarian for specific treatment recommendations.

Prevention and control measures include the following:

  • Monitor sulfur intake in both water and dry matter. Check sulfur content in water sources and forages. High sulfur intake can result in polio.
  • Provide feed with thiamine levels of 3 to 10 mg/kg of feed.
  • Provide sufficient levels of roughage through good-quality pasture or hay as part of the diet.
  • Monitor animals after you have administered drugs such as amprolium.

Pregnancy Toxemia (Ketosis)

Pregnancy toxemia is a metabolic disorder. Susceptibility increases 1 to 3 weeks from kidding or lambing in older, fat does/ewes carrying multiple fetuses. Pregnancy toxemia is associated with prepartum mortality.

In cases where there is insufficient nutritional energy intake during late pregnancy, does and ewes burn fatty tissue as an alternative source of energy to facilitate glucose availability to the fetuses, for milk production, and for the dam’s maintenance.

Utilization of some internal fatty tissue during pregnancy is not harmful. Excessive utilization of stored fats, however, will result in the overproduction of toxic byproducts or ketone bodies that are then released into the blood circulation. This causes an increase in hepatic fat accumulation (fatty liver) that in turn harms both the liver and kidneys.

Symptoms include the following:

  • little or no appetite
  • lethargy or sluggishness
  • muscular imbalance or poor coordination, known as ataxia. Affected animals often lie down and in many cases are not be able to rise again.
  • grinding of teeth
  • blindness
  • coma or even death

Diagnosis is based on herd history and clinical signs. The amount of ketone bodies can be determined by using commercial quantitative tests. Prognosis is given based on the levels of ketone bodies, dehydration, and hepatic and renal failure that occur.

Treatment with propylene glycol, or an alternative appropriate energy supplement, can be successful if animals are treated early in the course of the disease. Administration of sodium bicarbonate solution intravenously or orally is also commonly used to treat ketoacidosis. Contact your veterinarian for specific treatment recommendations.

If possible, consider an ultrasound to determine the number of viable fetuses the doe or ewe is carrying. If the fetuses are dead, then a fetotomy, which is the removal of dead fetal tissues and placenta, may be recommended. Consider the induction of labor in dams that are close to kidding or lambing. Consult your local veterinarian if a cesarean section is needed. Consider administering vitamin B complex intramuscularly and probiotics orally. Treatment should be discontinued when the doe/ewe presents signs of improvement.

Good feeding management is needed throughout pregnancy, but especially during the later stages of pregnancy. During the last 6 weeks of gestation, consider supplying concentrated rations with ionophores to increase the ruminal utilization of volatile fatty acids, which in turn will be used in the production of energy. Also avoid stress and sudden dietary changes during late pregnancy.

For more information about specific diseases of dairy goats and sheep, refer to the Alabama Cooperative Extension System website at www.aces.edu.

 

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