Chapter 11 Gnotobiotics Flashcards
Gnotobiotics
“well-known life”, is the study of animals whose microflora is completely defined.
Germ-free, also known as axenic
free of all demonstrable microorganisms.
defined flora (DF)
DF animals are animals that were originally germ-free but were given a known group of bacteria and/or other organisms to aid their digestive functions.
specific pathogen-free animals (SPF).
SPF animals have normal flora but are free of particular organisms, usually pathogenic, but they are not gnotobiotes.
isolator system
is a device that creates a barrier between animals and the outside environment, either by preventing microorganisms outside the system from entering the isolator (exclusion), or by confining potentially harmful microorganisms within the system (containment).
Rigid isolators
are constructed of stainless steel or Plexiglas®.
Flexible isolators
are usually made of clear polyvinyl or polyurethane plastic film
Semi-rigid isolators
may be made of impact-resistant material (such as polypropylene) on all but one side and have a flexible film (such as polyurethane) on the front side.
Flexible film isolators are considerably less expensive than stainless steel isolators
How long must isolators undergo testing?
3-6 weeks
Laminar flow cabinets or laminar flow racks
provide a cage or rack environment with a large volume of air that is filtered, sterile, and in a laminar flow.
Nutrient requirements also differ for axenic animals
hey tend to have higher requirements for total food and water intake, vitamin K, B vitamins, and choline than nonaxenic animals.
They have lower requirements for vitamin A and vitamin E, and for the amino acids lysine and cysteine.
What diseases can pass through the placenta barrier?
Mycoplasma spp. and Pasteurella spp.
Kilham rat virus and lymphocytic choriomeningitis virus
Schaedler cocktails
a “cocktail” of normal symbiotic (nonpathogenic) intestinal bacteria to normalize the gut physiology and anatomy.
defined flora animals
Animals that have received a cocktail of known microorganisms
resume text book flashcards from defined flora animals
resume text book flashcards from defined flora animals
name the two types of gnotobiotic animals?
axenic (germ free) and defined flora
…..is a cocktail of normal symbiotic intestinal bacterial given to axenic animals to normalize gut physiology.
Schaedler cocktail