Intramuscular Administration 18 Intramuscular Injection in Mouse, Rat, and Guinea Pig 18 Intramuscular Injection in Cattle, Sheep 20 Intramuscular Injection in Pig 21 Intraperitoneal Administration 22 Intraperitoneal Injection in Mouse 22 Intraperitoneal Injection in Rat or Guinea Pig 23 Oral or Nasogastric Administration 24 Oral Intubation (Gavage) of Rodents (Mouse, Rat, and Guinea Pig) 24 Nasogastric Intubation in Rabbits 27 Gastric Gavage of Pig 28 Nasogastric Intubation of Horse 29 Inhalation, Intratracheal, or Intranasal Administration 31 Surgical Intratracheal Administration in Rodents 31 Intranasal Injection in Rodents 31 Intratracheal Administration of Sheep 32 Intracardiac Administration 32 Intracardiac Injection of Rat Pups 33 Equipment/Materials (items utilized will depend upon the species and route of administration) Sterile disposable needles (0.5-1.5 inches) Gauge 18, 20, 21, 22, 23, 25, 27, 28, 30 Syringes (e.g. 1 mL, 3 mL, 6 mL, 10 mL, 12 mL, 60 mL) Catheter 3-way stop valve with luer-lock attachment Adaptor or injection cap Intubation tubes (see below) Vaseline Oil of Wintergreen; lidocaine topical (2% xylocaine jelly, EMLA, Topicaine) Cordless hair trimmer; razor blade; electric clippers Restraint tube (50 mL tube with open bottom) or appropriate restraint device (e.g. towel, cat bag; halter; mouth gag – sheep or calf; head-gate stantion) Plastic tubing or feeding tube (5 Fr, 15-16”; 24” plastic tubing, ¼” or 5/16” diameter) Skin disinfectant (e.g. betadine, hibitaine); 70% isopropyl alcohol Water and paper towels Sedatives (as appropriate for species)
Unable to find vessel Position of the animal during the restraint may be inappropriate. Reposition head or limb. Rolling vessel or loss of blood flow If vein bounces away from needle as you go through the skin, stabilize the vein by placing thumb on one side and placing tension on the skin. If blood flow is lost check for the following: a) bevel of needle is lodged against wall of vein so rotate the needle slightly; b) loss of blood pressure in the vein so apply digital pressure or stop aspiration for a moment to allow vein to refill with blood; c) needle is dislodged from vein so reposition the needle back into the vein. Animal moves excessively during procedure Re-evaluate restraint and/or get help. Operator safety is the utmost concern when working with animals. Do not proceed unless animal is appropriately restrained. For oral intubation – failure to enter the ventral meatus or for animal to swallow tube Remove the tube and over. Get help from trained personnel if you are unsuccessful on 2-3 attempts. Gently rotate and/or blow on the tube. Gently move the tube back and forth. For horses – instruct assistant to place a finger inside the horse’s mouth (at diastema) and make it chew. Most horses will swallow once they finish chewing, therefore watch closely and be prepared. For oral intubation – tube enters trachea Retract the tube into the pharynx, re-evaluate its position and try again. Instruct the assistant to flex the animal’s neck to reduce possibility of passage into the trachea. Get help from trained personnel if you are unsuccessful on 2-3 attempts. Nosebleed during nasogastric tubing Place a towel (large animal) or gauze (small animal) over the nose to avoid contamination of the area and clothing. Most nosebleeds stop within a few minutes. References