Ref Code: CAT20

Category

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

Research - 5

Objective

To remove a fat sample from the live animal to test for the presence of chemical residues, or possibly other contaminants.

Alternatives to animal use for teaching

Video

Details of Procedure

Animals used for teaching should be mid-range - Fat Score 3 (10mm fat at P8 site) or better. In animals actually requiring testing, sampling should be avoided if possible until the animals are in Fat Score 3, otherwise it may be difficult to obtain enough fat from a small incision.

Animals should be adequately restrained in a crush. The sampling site beside the tail, between the base of the tail and the pin bone, is cleaned and shaved, then disinfected by applying a swab of alcohol, then iodine.

Local anaesthetic is administered, a 40-50mm incision is made, and a sample of fat, sufficient to fill a matchbox, is removed.

It is advisable to prepare a cow in advance of the one being operated on, which should allow sufficient time for the local anaesthetic to take effect.

The fat sample is wrapped in aluminium foil and kept cool until it can be frozen and sent for laboratory analysis.

After the fat sample has been removed, the incision is sutured, usually with gut which is left to be absorbed. Excess blood should be wiped off, and if flies are a problem, the wound sprayed with insect repellent antibiotic spray.

Drugs, chemicals or biological agents

Local anaesthetic

Impact of procedure on welfare of animals

Minimal, provided local anaesthetic is given time to work, and normal hygienic practice is observed.

Reuse and repeated use

The operation may be repeated on the other side of the tail. Reuse of the same site would be possible after 6-8 weeks is allowed for healing.

Qualifications, experience or training necessary to perform this procedure

Demonstrator: Veterinarian experienced in the procedure.

Students: Other vets unfamiliar with the procedure, or veterinary students.