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Case-Bac (Canada)

This page contains information on Case-Bac for veterinary use.
The information provided typically includes the following:
  • Case-Bac Indications
  • Warnings and cautions for Case-Bac
  • Direction and dosage information for Case-Bac


This treatment applies to the following species:
Company: Colorado Serum


General Information

This product, when administered to healthy sheep according to label directions, will aid in the prevention and control of Caseous lymphadenitis, a disease characterized by localized collections of pus in the tissues of the body. These suppurative inflammations are most often referred to as abscesses but at times, when the disease is being discussed by those familiar with it, are also called boils.

Caseous lymphadenitis is a chronic disease of sheep in which clinical signs and lesions may not be observed for several months after the animals become infected. Causative bacteria are likely to be present on the skin of susceptible animals and exposure may occur through wounds resulting from shearing, scratches, splinters, thorns, and the like. Abrasions provide access to the organism which thereafter migrates to the lymph nodes of the body. Exposure may also occur by pulmonary transfer so over-crowding of animals should also be avoided. The disease is not usually fatal but condemnations may run as high as 20% when carcasses are inspected following slaughter. Weakness and emaciation may develop in animals that are not held for slaughter, followed by eventual death.

The disease is manifested in two forms: (1) external abscesses in the superficial (mandibular, prescapular, and prefemoral) lymph nodes and (2) internal abscesses in the visceral organs especially in the lung, liver, and kidney and in the mediastinal, bronchial, and lumbar lymph nodes. Both forms may occur simultaneously. The visceral form of the disease is implicated in the “thin ewe syndrome” and can cause loss of fertility.

Abscesses and lesions formed in Caseous lymphadenitis have a cheesy greenish-yellow to off-white odorless pus surrounded by a capsule. These lesions progressively enlarge.

In older abscesses the pus becomes somewhat dry and firm and will form concentric layers within the fibrous capsule. Corynebacterium pseudotuberculosis is easily isolated from such abscesses and is usually the only organism present.

Once the disease has been introduced into a flock of sheep a relatively large percentage of susceptible animals will be affected. The organism is likely to spread by contamination from ruptured or lanced abscesses or at shearing time. Any infected animals should be shorn last and the shearing equipment thereafter sterilized. It is essential, in the control of Caseous lymphadenitis, to exercise strict herd management with careful attention to examination, treatment, separation, and culling of the infected animals.

It has been shown that the product will control Caseous lymphadenitis when sheep are vaccinated prior to exposure to the disease. It has also been shown that little or no benefit can be expected when animals with visible signs of the disease are vaccinated. Those showing infection should be immediately culled from the flock and disposed of or held away from those animals that appear to be in good health.


Do not vaccinate within 21 days before slaughter.

Case-Bac Dosage And Administration

Inject 2 ml subcutaneously (axillary space). Repeat full 2 ml dose in 4 weeks (opposite axillary space).

Revaccinate annually using a single dose.


Anaphylactoid reaction may occur following administration of products of this nature. If noted, administer adrenalin or equivalent. Delayed treatment could result in an irreversible reaction.

Handling of the product, filling of syringes, etc., should be done as aseptically as possible. Great care has been taken to assure the purity of this preparation at the time of release for marketing. Reasonable precautions should be taken in the field to maintain this condition.


1. Store at 2° to 7° C. Do not freeze.

2. Shake well before use.

3. Sterilize syringes and needles by boiling in clean water.

4. Use entire contents when first opened.

5. Contains thimerosal as a preservative.

6. Conveniently packaged in 10 dose and 50 dose sizes.

7. Slight lameness (soreness) in lambs may be observed, along with lethargy, in a percentage of the mature animals following vaccination. Sheep are inclined to become depressed and may limp after foreign substances are administered or because of increased exertion and stimulation of vaccination. While noticeable, these symptoms usually disappear within 24-48 hours and can be considered minor vaccination reactions. If suggested care is taken in preparing vaccination equipment and in administering the product there should be no abscessation at the site of injection.

USDA Code 7A94.00

U.S. Vet. License No. 188

Manufactured by: COLORADO SERUM COMPANY, 4950 York Street, Denver, Colorado 80216


Contact us for more information on other Colorado Serum Company products.

Fine Veterinary Biologics since 1923





Order #

20 ml

10 Dose


100 ml

50 Dose


CPN: 1174004.3

4950 YORK STREET, P.O. BOX 16428-0428, DENVER, CO, 80216-0428
Telephone:   303-295-7527
Order Desk:   800-525-2065
Fax:   303-295-1923
Every effort has been made to ensure the accuracy of the Case-Bac information published above. However, it remains the responsibility of the readers to familiarize themselves with the product information contained on the Canadian product label or package insert.

Copyright © 2020 Animalytix LLC. Updated: 2020-10-21