Ref Code: CAT09

Category

Teaching - 3 (Instructor : student ratio 1:3)Research - 4

Objective

To collect mucosal scrapings using a sputum cup ("probang") for the diagnosis of foot-and-mouth disease.

Alternatives to animal use

Nil

Details of procedure

Foot-and-Mouth Disease (FMD) causes considerable suffering in animals and economic loss to their owners and the nation. In order to minimise spread, early accurate diagnosis is critical. Apart from obvious vesicles, the main site of replication of the virus of FMD is in the mucosae of the pharynx and oesophagus. Therefore, mucosal scrapings are used to isolate the virus. This may be necessary for:

1. The detection of carrier animals, particularly in cattle, which can carry the virus for up to 12 months
2. The detection of preclinical infections before vesicles and a serological response
3. The detection of subclinical infections, as were common in sheep in the United Kingdom during the 2001 outbreak
4. The determination of the infectivity of a viral strain during an outbreak
5. Import certification

To collect samples of mucosal scrapings from animals the following procedure should be followed:

1. Restrain the animal in a crush or head bail.
2. Pass the cup through the mouth over the dorsum of the tongue into the pharynx.
3. With short movements dorsally and laterally, scrape the epithelium of the soft palate and the wall of the pharynx.
4. Then pass the cup into the oesophagus as the animal swallows and let it pass about half the way down.
5. Gently remove the cup obtaining the mucosal scraping as you proceed.

The sample should then be checked for suitability. It must contain off-white remnants of mucosa and should not be contaminated with blood and excessive ruminal contents. If suitable, it should be diluted into phosphate buffered glycerine saline for transit to the laboratory.

Drugs, chemicals or biological agents

Nil

Impact of procedure on wellbeing of animal(s)

Procedure is well tolerated.

Reuse and repeated use

Animals should be used for one demonstration only.

Care of animal(s) during/after procedure

Observation

Pain relief measures

None required

Qualifications: Experience skills or training necessary to perform this procedure

Demonstrator: Extensive experience with this procedure. The procedure should be clearly demonstrated to students before they attempt it and they must be closely supervised.

Students: Understanding of the anatomy of cattle, experience in restraint of cattle.