For subcutaneous or intramuscular injections, use a 16 or 18 gauge needle.

For subcutanous injections, use a 1/2 inch or 3/4 inch needle.

For intramuscular injections, use a 1 inch or 1 1/2 inch needle.

For intravenous injections, use a 14 or 16 gauge needle, preferably 1 1/2 to 2 inches long to avoid injection of drug outside the vein, which causes a severe tissue reaction and the animal does not receive the adequate dose for recovery of condition.

Change needles every 10-15 uses.

Discard needles if they have a burr or bend or are dull.