Safeguards aimed at preventing a repeat of the BSE crisis must be improved, a Commons committee has said.
The UK's cattle tracing system still relies on hand-written records
The current system used to track cattle is "inefficient, overly burdensome and based on obsolete technology", said the public accounts committee.
The committee said the system was created "in haste" and was not adequate to control infectious diseases.
The MPs said in their report that there was an "urgent need" for improvement in Defra's systems.
The Cattle Tracing System was introduced after the BSE crisis to help prevent another outbreak.
The computerised system is supposed to record all livestock movements from birth to slaughter.
It costs £30m every year to run but the committee found more than one million uncorrected anomalies in the system.
Conservative MP Edward Leigh, who chairs the committee, said the system was more expensive and less efficient than those used in other EU countries.
He said: "There is an urgent need for improvement in Defra's systems for tracking livestock.
"The cattle tracing system
in particular is inefficient, overly burdensome, and based on obsolete
"It does not fully meet the needs of state veterinarians to control
outbreaks of infectious diseases amongst cattle, which is all the more
unacceptable given that it was introduced in response to the BSE crisis in the
Problems with the system have already resulted in £14m of penalties from
the European Commission.
Defra estimates that may rise to £50m if the problems are not sorted out.
BBC environment correspondent Tim Hirsch said that it still relies on hand-written records delivered by post.
"The government says it is moving towards greater use of computerised records and has taken step towards making the system more reliable," he said.
The CTS works alongside the Animal Movements Licensing System, which records all batch movements of cattle, sheep and pigs.
Defra has said it has plans for a new £136m integrated system known as the Livestock Identification and Tracing Programme.