Breeding of genetically modified animals

With the entry into force of the new Animal Protection Act on 12 July 2013, the breeding and keeping of genetically modified animal lines is subject to authorisation if the individuals of these lines may experience pain, suffering or damage as a result of their genetic modification.
The Federal Institute for Risk Assessment (BfR) has drawn up criteria for the application as well as for the load classification of contaminated lines:

A. mouse, rat

Assessment of the exposure of genetically modified mice and rats - Version 2
09.09.2016 Recommendation No. 002/2016 of the National Committee (TierSchG):
https://www.bfr.bund.de/cm/343/beurteilung-der-belastung-genetisch-veraenderter-tiere.pdf

Lines with a harmful phenotype: (examples):

• all genetically modified lines newly generated by embryonic manipulation (transgenesis, homologous recombination, enzyme-mediated mutation, transduction, etc.) or by irradiation or treatment with mutagenic substances
• all lines created by spontaneous mutations Generation of new lines by crossing two lines that are not loaded, if a load on the offspring of the crossing is expected. Only if it can be proven with certainty (e.g. literature) that there is no pollution in the offspring, an approval is not necessary.
• Progeny of crosses of genetically modified lines where exposure is expected
• Lines that develop tumours due to genetic modification are categorically (i.e. also in cases in which the tumours only occur after a certain age) subject to approval

The following lines are excluded (examples):

• Lines in which the genetically determined change in phenotype is only triggered by the administration of inducers (e.g. tamoxifen, tetracycline, etc.). Since induction is only carried out on animals in an approved animal experiment, the breeding of the line does not require approval.
• The presence of reporter genes (e.g. luciferase, LacZ) in the genome The molecules developing from these genes do not per se lead to a distressing phenotype, so that the breeding of lines in which only reporter genes have been introduced does not require approval.
• According to the current state of knowledge, the breeding of immunodeficient lines is not subject to authorisation if - in the sense of refinement - the stress caused by keeping the animals in conditions that protect them from pathogenic germs can be excluded. A lack of consideration of the level of hygiene in the animal welfare assessment of the breeding of immunodeficient animals is critical in terms of animal welfare. An adequate level of hygiene must be guaranteed in animal husbandry.
• Wild type animals from common inbred or outbred strains or wild type animals without standardised genetic background as well as recombinant inbred strains or comparable variants do not constitute genetically modified animals.
• Lines in which no strain is to be expected due to the type of genetic modification (e.g. Cre strains, Flox strains).

As in the past, the production of new strains by homologous recombination of embryonic stem cells or by pronucleus injection remains subject to approval. However, in future, a stress assessment must be carried out using the forms listed above.

B. Fish

Assessment of the exposure of genetically modified fish (bony fish, teleost fish)
06.08.2015 Recommendation No. 001/2015 of the National Committee (TierSchG):
Assessment of the exposure of genetically modified fish (bony fish, teleostei)

Considerations for a European animal welfare standard to evaluate adverse phenotypes in teleost fish
The Embo Journal 2016, 35, 1151-1154
emboj.embopress.org/content/35/11/1151