Morbidity diseases

1. Mycoplasma Pneumonia

A chronic, infectious respiratory disease that occurs worldwide. It is a mayor disease of swine that can severely limit feet conversion ant therefore profit. This disease is caused by the Mycoplasma organism. This particular strain of pneumonia is not zoonotic. It has been shown that the feed efficiency of affected pigs may be lowered by 25%. It is transmitted by contact (direct) between infected and normal swine. Pigs of all ages are susceptible, but between the ages of 14 to 26 weeks they are most prone to secondary lung complications.

Prevention

1. Avoid the purchase of animals from infected herds (quarantine new stock until you are sure of their health).

2. Prevent contact between your herd and free-ranging pigs.

Treatment

1. Treatments can help control bacterial complications. Tylosin, tetracycline, and streptomycin are used to treat this.

2. Treat for lungworms regularly (if they exist in your area) because they are a precursor of this disease since they are a common vector.

Symptoms

1. Coughing is the moat obvious symptom.
2. Diarrhea, a alight fever, ant a drop in weight gain are also symptoms. A poet-mortem exam would show lesions on the lungs.

Mortality losses are quite low (1 to 4%). It causes stunting of growth and a delay in reaching market weight. Good husbandry practices and reducing the stress on your herd are the best preventatives.

2. MMA Complex (Mastitis-Metritls-Agalactia Complex)

This is a disease of sows and gilts characterized by an inflammation of the mammary glance (mastitis), of the uterus (metritis), and/or a failure to secrete milk (agalactia). The mortality losses are low in sows, but high in the baby pigs. It is not zoonotic. It is more common in sows than gilts. How the disease is spread remains unclear. The organisms thought to cause the MMA syndrome include E. cold and Mycoplasma hyogenatalium. However, the disease is complex, and the actual cause is unknown.

Prevention

1. Sound management practices, good sanitation, etc.
2. Avoid overfatness and constipation of sows. 6-10% molasses in the ration will control constipation.
3. Minimize stress. Avoid deficiencies of phosphorus, calcium, vitamin E, and selenium.
4. Provide a well balanced and bulky gestation diet. Increase the feed after farrowing gradually.

Treatment

1. Antibiotics to eliminate infections (penicillin). Oxytocin to stimulate the sow's milk production. If this fails then the piglets should be hand-fed or placed with another now.

2. Nitrofuran or an oral antibiotic can be used if the piglets develop diarrhea.

Symptoms

1. The first signs of the disease usually appear within 3 days after farrowing. A whitish or yellowish discharge of pus appears from the vagina of the sow and the temperature may rise to 103 to 106°F. The sow goes off feed, stops milking, and the piglets often develop diarrhea. If the disease is not treated the piglets may starve to death.

2. The sow is not significantly affected and will recover.

3. Erysipelas

This is an acute or chronic infectious disease of growing swine. There are fewer instances of it in mature breeding stock and it is fairly common in many of the swine-raising areas of the world. It is caused by a bacterium and is zoonotic. This disease in man is called erysipeloid. This disease takes one of 3 forms: the acute, the subacute, and the chronic. The acute form causes death, but the chronic (milder) form is more damaging to the profit of the farmer. If the disease is endemic then young pigs will receive maternal antibodies through the colostrum and develop their own active immunity later. This organism may be shed by infected animals. Eating of infected feeds will lead to infection (this is how the disease is commonly spread).

Prevention

1. Vaccination by either killed bacteria or live strains of low virulence. Vaccination raises the level of immunity, but does not provide complete protection. Breeding stock should be revaccinated yearly. If there is an outbreak of the acute form an antiserum may be used on in-contact pigs that are not yet affected. The bacterium is able to reproduce either in the soil or in an infected animal making control very difficult.

Treatment

1. Penicillin is the most common antibiotic to use for this disease.

Symptoms

1. The acute form: Similar to the symptoms of hog cholera (high fever and purplish patches on the belly).

2. The subacute form: (Diamond-skin form) skin lesions will last from one to two weeks. The typical lesions are reddish rectangular plaques in the skin. Dry gangrene may affect the ears and tail.

3. The chronic form: Localizes in the ear and joints. The knees and hocks often become enlarged and stiff. These pigs are usually unthrifty.

4. Enteritis

This is a general term referring to several enteritic diseases, all of which produce an inflammation of the intestines. E. cold or Salmonells cholerae-suis may be among the common causes. Most outbreaks affect healthy, recently weaned pigs. Older animals seem less affected. It is often caused by the stresses of overcrowding, unusually high or low temperatures, and a sudden change in the feed ration. It is not zoonotic. Internal parasites and a deficiency of some B-complex vitamins may also cause enteritis.

Prevention

1. Good sanitation and management practices.
2. Oral vaccination using killed E. cold antigens in the feed rations of weaner hogs may help as well.

Treatment

1. Limit the feed immediately and then restore it gradually over several days.
2. All affected pigs should be treated with one of the following mixed in their drinking water: neomycin, streptomycin, chloretetracyline, tetracycline, oxytetracycline, ampicillin, or nitrofurazone.

Symptoms

1. Depression, anorexia, slight fever, dehydration, and a brownish or grayish diarrhea.
2. Postmortem findings include: dehydration, a stomach filled with feed, and reddening of the small intestinal wall.

5. Influenza (Flu)

This la an acute, highly contagious respiratory disease. It is fairly common in Kenya. It is spread as an airborne infection within a herd, but not from herd to herd. Mortality losses are quite low and the disease only lasts 3 to 7 days. It appears suddenly, and in most cases all pigs that are infected show symptoms at the same time. This disease resembles the influenza of man, but is spread by a different virus and is not zoonotic. This disease is produced by a combination of a bacterium and a virus. The bacterium alone cannot cause disease, but is able to exist in a recovered pig for an extended period. The virus can cause a mild infection alone, but cannot survive in a healthy animal. Instead, the virus is found in the lungworm of the pig. The earthworm, however, serves as an intermediate host for the lungworm. That makes the life history as follows: The adult lungworm lays its eggs (containing the virus) in the lung of the infected pig, from which the eggs are coughed up, swallowed, and eliminated in the feces. Here the eggs hatch into larvae almost immediately. These larvae must then pass into (be eaten by) the earthworm before becoming infective. The pig then eats the earthworm that contains the lungworm larvae, which may in turn harbor the virus. These larvae then pass into the digestive tract, enter the lymph system, and migrate to the lungs. Here in the presence of the bacterium, the disease starts.

Prevention

1. Use dry and clean pens and rotate pastures to break up the life cycle of the lungworm.

Treatment

1. Antibiotics or sulfa drugs given by injection or through the drinking water to reduce the chance of secondary infections.

2. Attempt to reduce any poor management practices that create stress on the herd.

Symptoms

1. Following a one week incubation period the disease will appear suddenly. High fever, lose of appetite, a cough, and discharge from nose and eyes are seen. The hogs may sit up like dogs in order to breathe easier.

Table 2-8

Disinfectant Guide

HANDY DISINFECTANT GUIDE

(Chemical agents should not be relied upon spores; controlled and prolonged heat is required to kill spores.)