GM animals

Genetically modifying animals is much harder than genetically modifying plants or microorganisms. Examples of genetically modified animals are African swine fever-resistant pigs and Atlantic salmon receiving genes that cause faster growth from Chinook salmon.The genes cause them to produce growth hormone all year round so they grow to full adult size in half the usual time.GM animals are also used to produce medicines for humans (pharming). Genes expressed in mammary gland cells can produce human proteins which can be harvested in the milk of the animals.Using animals such as knock-out mice that lack certain genes for research is also widely carried out.However, there are ethical and animal welfare issues including whether or not it is right to put human genes into animals.