Probably the most persuasive argument presented by groups opposing animal use in research is of pain and suffering being inflicted on these subjects. Most of the moral/ethical issues are rooted in the following scenario: a) if animals are assumed to react similarly to man to stimuli and drugs; b) and data collected from animal experiments is used to predict how stimuli or drugs will act in humans; c) then animals must possess man’s ability for feeling pain and for suffering.
The appropriate use of anesthetics, analgesics and tranquilizers is not only an important facet of the provision of humane care, but is also important to the collection of valid research data. Animals that are in pain or are severely distressed cannot be expected to demonstrate “normal” physiologic responses. The attending veterinarian should serve as an institutional resource for information concerning the choice and use of these medications.
Amphibians must be kept moist over their entire bodies during anesthesia and recovery. Care must be taken that they do not become immersed, as this will result in drowning.
Tricaine (MS 222) -ethyl m-amino benzoate methanesulfonate (tricaine methane sulfonate)
Should be buffered to neutral pH before use. MS222 must be disposed as chemical waste.
Immerse in water with agent added: 1:2000 to 1:1000 for adults (i.e.,5-10mg of tricaine in 1000 ml water)
1:3000 to 1:5000 for larvae
Atropine (0.01-0.02mg/kg) may be administered subcutaneously or intramuscularly as a preanesthetic agent approximately 30 minutes before anesthesia. Atropine prevents the drop in heart rate and excessive salivation that may be caused by agents such as inhalant anesthetics and ketamine. Glycopyrrolate (Robinal®) (0.02-0.04 mg/kg) subcutaneously or intramuscularly is an effective alternative to atropine when given 15 minutes prior to surgery. Glycopyrrolate has a longer duration of action than atropine.
Body temperature = 38-39.6oC
Heart rate = 130-325/min
Respiratory rate = 32-60/min
Tidal volume = 4-6 ml/kg
Many rabbits have serum atropinesterase which causes reduced response to atropine.
Glycopyrrolate, another anticholinergic, can be used instead of atropine.
Unique hypnotism or immobilization reflex has been observed in rabbits in the absence of drug use.
Body temperature = 37.2-39.5oC
Heart rate = 230-380/min
Respiratory rate = 42-104/min
Tidal volume = 2.3-5.3 ml/kg
Large cecum can act as reservoir for anesthetics. Depending on drug solubility, the cecum can alter the pharmacologic effect.
Induction of anesthesia using volatile anesthetics (e.g., halothane and isoflurane) should be done with caution due to initial breath holding when animals are first exposed to irritating gas vapors.
Body temperature = 37-38oC
Heart rate = 250-500/min
Respiratory rate = 35-135/min
Tidal volume = 0.6-1.4 ml
Syrian or golden hamster is very resistant to morphine - no sedation or hypnotic effects.
Syrian or golden hamster has an increased tolerance to pentobarbital.
Atropine 0.1 mg/kg IP IM SC
Ketamine, C-III (Ketaset®, Vetalar®) 22-44 mg/kg IM
Body temperature = 35.9-37.5oC
Heart rate = 250-450/min
Respiratory rate = 70-115/min
Tidal volume = 0.6-2.0 ml
Male rats and animals receiving low calorie diets require higher doses of barbiturates.
Avertin has been reported to cause ileus in rats.
The therapeutic dose for carbon dioxide is close to the lethal dose; very short acting. Concurrent administration of 10-50% O2 is recommended.
Body temperature = 36.5-38.0oC
Heart rate = 325-780/min
Respiratory rate = 94-163/min
Tidal volume = 0.09-0.23 ml
The use of chloroform as an anesthetic agent is discouraged. Chloroform can cause renal tubular calcification and/or necrosis, particularly in male mice; DBA/2 strain most susceptible.