Animal testing on rodents
Encyclopedia
Rodents are commonly used in animal testing, particularly guinea pig
s, hamster
s, gerbil
s, rats
, and mice
.
In the U.S., the numbers of rats and mice used are not reported, but have been estimated at 15–20 million per year. In 2000, the Federal Research Division, Library of Congress, published the results of an analysis of its Rats/Mice/and Birds Database: Researchers, Breeders, Transporters, and Exhibitors.
They are widely considered to be the prime model of inherited human disease
and share 99% of their gene
s with humans. With the advent of genetic engineering
technology, genetically modified mice can be generated to order and can cost hundreds of dollars each.
Transgenic animal production consists of injecting each construct into 300–350 eggs, typically representing three days' work. Twenty to fifty mice will normally be born from this number of injected eggs. These animals are screened for the presence of the transgene
by a polymerase chain reaction
genotyping assay. The number of transgenic animals typically varies from two to eight.
Chimeric mouse production consists of injecting embryonic stem cells provided by the investigator into 150–175 blastocysts, representing three days of work. Thirty to fifty live mice are normally born from this number of injected blastocyst
s. Normally, the skin color of the mice from which the host blastocysts are derived is different from that of the strain used to produce the embryonic stem cells. Typically two to six mice will have skin and hair with greater than seventy percent ES cell contribution, indicating a good chance for embryonic stem cell contribution to the germline
.
Guinea pig
The guinea pig , also called the cavy, is a species of rodent belonging to the family Caviidae and the genus Cavia. Despite their common name, these animals are not in the pig family, nor are they from Guinea...
s, hamster
Hamster
Hamsters are rodents belonging to the subfamily Cricetinae. The subfamily contains about 25 species, classified in six or seven genera....
s, gerbil
Gerbil
A gerbil is a small mammal of the order Rodentia. Once known simply as "desert rats", the gerbil subfamily includes about 110 species of African, Indian, and Asian rodents, including sand rats and jirds, all of which are adapted to arid habitats...
s, rats
Laboratory rat
A laboratory rat is a rat of the species Rattus norvegicus which is bred and kept for scientific research. Laboratory rats have served as an important animal model for research in psychology, medicine, and other fields.- Origins :...
, and mice
MICE
-Fiction:*Mice , alien species in The Hitchhiker's Guide to the Galaxy*The Mice -Acronyms:* "Meetings, Incentives, Conferencing, Exhibitions", facilities terminology for events...
.
The statistics
In the UK in 2004, 1,910,110 mice, 464,727 rats and 37,475 other rodents were used (84.5% of the total animals used that year). In 2005, the total number of rodents used was similar to the previous year: 1,955,035 mice, 414,335 rats and 40,856 other rodents.In the U.S., the numbers of rats and mice used are not reported, but have been estimated at 15–20 million per year. In 2000, the Federal Research Division, Library of Congress, published the results of an analysis of its Rats/Mice/and Birds Database: Researchers, Breeders, Transporters, and Exhibitors.
Over 2,000 research organizations are listed in the database, of which approximately 500 were researched and of these, 100 were contacted directly by FRD staff. These organizations include hospitals, government organizations, private companies (pharmaceutical companies, etc.), universities/colleges, a few secondary schools, and research institutes. Of these 2,000, approximately 960 are regulated by USDA; 349 by NIH; and 560 accredited by AALAC. Approximately 50 percent of the organizations contacted revealed a specific or approximated number of animals in their laboratories. The total number of animals for those organizations is: 250,000–1,000,000 rats; 400,000–2,000,000 mice; and 130,000–900,000 birds.
Mice
Mice are the most commonly used vertebrate species, popular because of their availability, size, low cost, ease of handling, and fast reproduction rate.They are widely considered to be the prime model of inherited human disease
Genetic disorder
A genetic disorder is an illness caused by abnormalities in genes or chromosomes, especially a condition that is present from before birth. Most genetic disorders are quite rare and affect one person in every several thousands or millions....
and share 99% of their gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
s with humans. With the advent of genetic engineering
Genetic engineering
Genetic engineering, also called genetic modification, is the direct human manipulation of an organism's genome using modern DNA technology. It involves the introduction of foreign DNA or synthetic genes into the organism of interest...
technology, genetically modified mice can be generated to order and can cost hundreds of dollars each.
Transgenic animal production consists of injecting each construct into 300–350 eggs, typically representing three days' work. Twenty to fifty mice will normally be born from this number of injected eggs. These animals are screened for the presence of the transgene
Transgene
A transgene is a gene or genetic material that has been transferred naturally or by any of a number of genetic engineering techniques from one organism to another....
by a polymerase chain reaction
Polymerase chain reaction
The polymerase chain reaction is a scientific technique in molecular biology to amplify a single or a few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence....
genotyping assay. The number of transgenic animals typically varies from two to eight.
Chimeric mouse production consists of injecting embryonic stem cells provided by the investigator into 150–175 blastocysts, representing three days of work. Thirty to fifty live mice are normally born from this number of injected blastocyst
Blastocyst
The blastocyst is a structure formed in the early embryogenesis of mammals, after the formation of the morula. It is a specifically mammalian example of a blastula. It possesses an inner cell mass , or embryoblast, which subsequently forms the embryo, and an outer layer of cells, or trophoblast,...
s. Normally, the skin color of the mice from which the host blastocysts are derived is different from that of the strain used to produce the embryonic stem cells. Typically two to six mice will have skin and hair with greater than seventy percent ES cell contribution, indicating a good chance for embryonic stem cell contribution to the germline
Germline
In biology and genetics, the germline of a mature or developing individual is the line of germ cells that have genetic material that may be passed to a child.For example, gametes such as the sperm or the egg, are part of the germline...
.
See also
- Animal modelAnimal modelAn animal model is a living, non-human animal used during the research and investigation of human disease, for the purpose of better understanding the disease without the added risk of causing harm to an actual human being during the process...
- Animal testing on invertebratesAnimal testing on invertebratesMost animal testing involves invertebrates, especially Drosophila melanogaster, a fruit fly, and Caenorhabditis elegans, a nematode. These animals offer scientists many advantages over vertebrates, including their short life cycle, simple anatomy and the ease with which large numbers of individuals...
- Animal testing on non-human primatesAnimal testing on non-human primatesExperiments involving non-human primates include toxicity testing for medical and non-medical substances; studies of infectious disease, such as HIV and hepatitis; neurological studies; behavior and cognition; reproduction; genetics; and xenotransplantation. Around 65,000–70,000 are used every...
- BALB/cBALB/cBALB/c is an albino, laboratory-bred strain of the House Mouse from which a number of common substrains are derived. Now over 200 generations from their origin in New York in 1920, BALB/c mice are distributed globally, and are among the most widely used inbred strains used in animal...
- C57BL/6
- Mouse models of colorectal and intestinal cancerMouse models of colorectal and intestinal cancerMouse models of colorectal cancer and intestinal cancer are experimental systems in which mice are genetically manipulated or challenged with chemicals to develop malignancies in the gastrointestinal tract...
- Preclinical imagingPreclinical imagingPreclinical imaging is the visualization of animals for research purposes, such as drug development. Imaging modalities have long been crucial to the researcher in observing changes, either at the organ, tissue, cell, or molecular level, in animals responding to physiological or environmental changes...
- Rat ParkRat ParkRat Park was a study into drug addiction conducted in the late 1970s , by Canadian psychologist Bruce K. Alexander and his colleagues at Simon Fraser University in British Columbia, Canada....
- Testing cosmetics on animalsTesting cosmetics on animalsTesting cosmetics on animals is a form of animal testing, intended to ensure the safety and hypoallergenic properties of the products for use by humans...
External links
- Information about mouse models from HOPES:Huntington's Disease Outreach Project for Education at Stanford