General Considerations Regarding Treatment and Prophylaxis of Pneumonia

Antibiotic therapy should be begun with a drug that is nor­mally effective against the organisms suspected to be pre­sent in the pneumonic process. Anthelmintics should also be given if verminous pneumonia is suspected.

Choice of Antibiotic and Duration of Therapy

Initial treatment is usually determined by the practition­er's previous experiences and by the available drugs that are legal to use in a food animal in the country. In the United States, ceftiofur is a good choice as it is labeled for goats with no meat or milk withdrawal. Tilmicosin should not be used in goats, as this antibiotic has caused fatalities (Jordan et al. 1993 and anecdotal reports). If a culture and sensitivity report is available from a tracheal aspirate or a necropsy, the choice of the antibiotic should be guided by that report. This is the preferred approach to address grow­ing concerns about antimicrobial resistance. Commonly, however, additional or different organisms are involved in the pneumonia. The practitioner should reevaluate the patient after 48 hours. If a definite response to therapy has not occurred (i.e., decreased fever, improved appetite and demeanor), another antibiotic should be chosen and administered for 48 hours. When a response is obtained, the effective drug should be continued until at least 48 hours after the goat is clinically normal. This means a minimum of four to five days of therapy for any goat with pneumonia. On the other hand, weeks of treatment are generally not possible, because of the pain and mental anguish most goats suffer during a prolonged series of injections. Mycotic pneumonia is also a possible sequela to prolonged antibiotic use.

Ideally, any sick animal receiving treatment should be removed from the herd and kept in isolation facilities. This often is not possible, or the owner refuses to put forth the required effort.

Drug Dosage and Extralabel Use

The dosage rate should be enough to achieve the tissue levels in the lungs that are necessary for the desired anti­microbial effect. When this dose is increased or is given more frequently than labeled dosage rates, or when the drug is not approved for goats, the practitioner must deal with government regulations regarding extralabel drug use. The animal to be treated must be carefully examined by the veterinarian, and provision must be made for pro­longed withdrawal periods to prevent contamination of milk or meat for human consumption. In the United States, all goats of all breeds are defined by the Food and Drug Administration as food animals, which limits the choice of legal antibiotics (fluoroquinolones are forbid­den). Routine milk and urine antibiotic residue tests after treatment are recommended, because pharmacokinetic data for goats to establish withholding times is rarely avail­able (Lofstedt 1987).

Routes of Administration

Except for sulfonamides and lesser doses of tetracyclines, oral use of antimicrobial drugs generally leads to severe systemic illness by interfering with rumen flora. In addi­tion, sick animals usually do not eat or drink well enough to dependably consume medication in feed or water. It is the personal preference of the author to give most antibiot­ics by SC injection. Painful muscle necrosis is thereby avoided, as is paralysis from accidental injection into the sciatic nerve. There are several caveats with SC injections. First, sterile abscesses sometimes occur and can be confused with caseous lymphadenitis. Therefore, injection ahead of the shoulder should be avoided in show goats. Second, the pharmacokinetic disposition of most drugs in goats has not been studied after SC administration and residue persistence is apt to be erratic.

Supportive Therapy

Many supportive drugs have been used to treat pneumonia. Naturally, a drug effective against lungworms should be administered if historical or laboratory findings suggest parasite involvement. In general, vitamins (including vita­min E and selenium in deficient areas) are part of the rou­tine regimen. Bronchodilators probably have a place in select cases, but proper dosages have not been determined scientifically. Corticosteroids are best avoided, because they increase the frequency of relapse when treatment is discontinued. Pneumonia is generally a very painful condi­tion, thus non-steroidal anti-inflammatory agents such as flunixin meglumine (IV, intramuscularly, or orally at 2.2 mg/kg; Konigsson et al. 2003) or meloxicam (1 mg/kg orally per day) are appropriate. However, these drugs are antipyretic and, if administered, body temperature cannot be used as an indicator of response to antimicrobial ther­apy. Exudates should not be allowed to obstruct the nares, and aromatic oils can be tried if rapid production of mucus is adding to the distress of the goat. The goat should be kept comfortable with a coat in cold weather, fan under very hot conditions, dry bedding, and good food and water within easy reach.

Pneumonia Prophylaxis

Prophylaxis of pneumonia, except of contagious myco­plasma pneumonia, is almost never through vaccination. Instead, careful attention must be paid to proper ventila­tion, housing, and nutrition. An increased colostrum intake should be encouraged and dry bedding provided for kids. In cold climates, supplying newborn kids with wool body socks prevents chilling without interfering with barn ventilation. Angora and Cashmere kids should not be shorn during inclement weather and supplemental feed may be required after shearing. When animals must be worked in a dry and dusty corral, wetting down the area with a 5% formalin solution has been proposed to decrease the quantities of both irritant dust and infec­tious microorganisms inhaled by the goats.

Strict isolation of purchased animals or those stressed by traveling and showing is also important. The etiology of the febrile illness accompanied by coughing that frequently sweeps through a goat herd after a show is rarely identified. Viruses, mycoplasmas, chlamydia, and pasteurellosis are possible suspects. One approach to handling the herd is to administer tetracycline, tylosin, or ceftiofur to goats that are off feed or febrile. Close observation, good feed, and good ventilation suffice if the animals are eating well.

In some instances, specific diseases such as mycoplasmal infections are controlled by separating kids from adults and feeding heat-treated colostrum and pasteurized milk. Pooled milk from other goats at a show should not be fed to members of one's own herd.