Bacterial Pneumonia in Goats

Introduction

Pneumonia is one of the most common respiratory problems in small ruminants throughout the world. In goat herds, pneumonia increases production costs associated with expensive treatments. Although pneumonia often occurs in kids, illness and deaths also occur in adult animals.

Pneumonia occurs when infectious and non-infectious agents cause the lungs of goats to become inflamed. The most frequent causes of respiratory infection and death are Pasteurella multocida or Mannheimia haemolytica (previously called Pasteurella haemolytica). P. multocida and M. haemolytica are commonly found in the upper respiratory tract of healthy goats. M. haemolytica are subdivided in two groups, A and T. Type A is most prevalent and is associated with a severe form of pneumonia. Goats that survive an acute stage may recover or become chronically infected with reduced lung capacity. Pneumonia caused by P. multocida and M. haemolytica can lead to significantly decreased growth performance. These two pathogens (agents that cause disease) cause outbreaks of acute pneumonia in goats of all ages. Respiratory infections from these pathogens are associated with poor management practices, occur as a secondary infection, or occur as a consequence of severe stress. Transportation stress, viral infections (e.g., parainfluenza-3 virus), lung parasites, prior bacterial infections, overcrowded pens, poor housing conditions, sudden environmental changes, and other stressful conditions increase goats' susceptibility to P. multocida and M. haemolytica pneumonias.

Goat with nasal mucopurulent discharge

Bacterial, viral, and parasitic infections break down goats' tissue defense barriers. Loss of this natural protection increases the goat's susceptibility to secondary infection by P. multocida and M. haemolytica. Animals whose lungs are already weakened from previous diseases will suffer from leukotoxins and lipopolysaccharides, both potent toxins that, in high levels, promote inflammation and severe lung damage. In kids, acute outbreaks can occur with low morbidity rates but high mortality rates. Typically, several kids that appear healthy die suddenly. Signs of the disease may not be noticed until later, after several animals have died.

Optimal conditions for pneumonia caused by P. multocida and M. haemolytica include the following:

• Viral diseases
• Sudden environmental changes
• High air humidity
• Poor hygiene and barn ventilation
• Severe internal parasites (worms and coccidia)
• CL (caseous limphadenitis) infections
• Poor nutritional management, undernourishment, or sudden change in diet
• Transportation stress
• Crowded pens with poor ventilation, or where animals have been relocated or transported can cause outbreaks.
  

Signs of Pneumonia

• Fever with temperature of 104 degrees F (40 degrees C) to 106 degrees F (41 degrees C)
• Moist, painful cough, dyspnea (difficulty in breathing). Examination of the lungs may reveal cracklelike sounds, along with nasal and ocular mucopurulent discharge
• Anorexia (loss of appetite)
• Depression

Diagnosis

Diagnosis is based on clinical signs and herd history. Dead animals can be used for a definitive diagnosis. Isolation and culture of the bacteria harvested from a tracheal wash and from pulmonary secretions can be used to isolate and identify the causal agent. A necropsy of lobes from the lungs will show hemorrhagic (bloody) secretion, and possibly pus and dead tissue lesions. Diagnostic labs also use the polynucleotide chain reaction (PCR) technique, which can be costly, and immunohistochemical techniques. These analyses are valuable in identifying causal agents and determining treatment and preventive methods. Consult a veterinarian for diagnosis of small ruminant pneumonia. The veterinarian can also assist in the necropsy and in sending samples to a diagnostic laboratory for further analysis.

A recropsy of lobes from the lungs will show hemorrhagic (bloody) secretion, and possibly pus and dead tissue lesions.

Treatment

Medicines effective in treating pneumonia in goats include penicillin, ampicillin, tetracycline, oxytetracycline, tylosin, florfenicol, and ceftiofur. Ceftiofur (Naxcel is the Pharmacia & Upjohn product trade name) is the only FDA-approved antibiotic to treat caprine pneumonia. The daily dosage is 0.5 to 1.0 mg/lb body weight injected intramuscularly for three days. Consult the manufacturer's guide for complete product usage and storage instructions. Probiotics are recommended after antibiotics to promote regrowth of the normal rumen microflora (bacteria and protozoa populations).

With the exception of ceftiofur, the FDA has not approved the antibiotics discussed for treating goats. Their use is considered extra-labeled, requiring consultation with a veterinarian for product usage and guidance.

Prevention

• Vaccinate the herd, a systematic vaccination of the entire herd is advised. The FDA has approved a P. multocida - M. hemolyticum vaccine for use in goats from Colorado Serum Company. The product label provides recommendations for vaccinating goat kids up to six months of age. For complete product usage and storage consult the manufacturer's guide. This vaccine may cause temporary limping in a few goats.
• Improve management practices by providing optimal sanitation and air quality in housing.
• Minimize transportation stress.
• Quarantine new animals before introducing them into the existing herd.
• Administer trace minerals, such as Cu, Se, and Zn, to enhance immune function. Adding vitamin E to receiving diets at pharmacological levels (e.g., > 1,000 IU/animal daily) also seems to be beneficial.
• Provide good quality hay and water, and supplement as appropriate.
• Consult a veterinarian to prescribe and administer a decongestant and anti-histaminic drugs to reduce lung congestion.
• Keep sick goats in a dry, well-ventilated location away from the rest of the herd.
  

Goat with nasal mucopurulent discharge

References

Ackermann, M. R. & Brogden, K. A. (2000). Responses of the ruminant respiratory tract to Mannheimia (Pasteurella) haemolytica. Microbes and Infection, 2(9), 1079-1088.

Berge A. C., Sischo, W. M., & Craigmill, A. L. (2006). Antimicrobial susceptibility patterns of respiratory tract pathogens from sheep and goats. Journal of the American Veterinary Medical Association, 229(8), 1279-1281.

Brogden, K. A., Lehmkuhl, H. D., & Cutlip, R. C. (1998). Pasteurella haemolytica complicated respiratory infections in sheep and goats. Veterinary Research, 29(3-4), 233-254.

Daniel, J. A., Held, J. E., Brake, D. G., Wulf, D. M., & Epperson, W. B. (2006). Evaluation of the prevalence and onset of lung lesions and their impact on growth of lambs. American Journal of Veterinary Research, 67(5), 890-894.

Duff, G. C., & Galyean, M. L. (2006). Recent advances in management of highly stressed newly received feedlot cattle. Journal of Animal Science.

Oros, J., Fernandez, A., Rodriguez, J. L., & Poveda, J. B. (1997). Bacteria associated with enzootic pneumonia in goats. Zentralblatt für Veterinärmedizin. Reihe, Journal of Veterinary Medicine, Series B, 44(2), 99-104.

Merck & Company. (2006). Pasteurellosis of Sheep and Goats: Introduction. Merck Manual.Whitehouse Station, NJ: Merck & Company.

Ramirez-Romero, R., & Brogden, K. A. The potential role of the Arthus and Shwartzmanreactions in the pathogenesis of pneumonic pasteurellosis. Inflammation Research, 49(3), 98-101.

Young, J. D., Jr., & Griffith, J. W. (1985). Spontaneous Pasteurella pneumonia in adultlaboratory goats complicated by superinfection with Corynebacterium pseudotuberculosis and Muellerius capillaris. Laboratory Animal Science, 35(4), 409-411.

Maria Lenira Leite-Browning, DVM, MS, Extension Animal Scientist, Alabama A&M University

For more information, contact your county Extension office. Visit http://www.aces.edu/counties or look in your telephone directory under your county's name to find contact information. Issued in furtherance of Cooperative Extension work in agriculture and home economics, Acts of May 8 and June 30, 1914, and other related acts, in cooperation with the U.S. Department of Agriculture. The Alabama Cooperative Extension System (Alabama A&M University and Auburn University) offers educational programs, materials, and equal opportunity employment to all people without regard to race, color, national origin, religion, sex, age, veteran status, or disability.