Almost 16,000 more animals were abandoned last year than in 2007, according to the RSPCA, who warned that pet owners are struggling to make ends meet in times of economic hardship.
The charity said 40,595 animals were abandoned in 2011, compared with 24,638 in 2007, a near 65% increase.
Over the same period, and despite efficiency savings, the charity's running costs have risen 8% from £111m to £120m.
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A roller coaster has reportedly come off the rails at a theme park in Scotland.
"I saw a lot of smoke come out from the tail-end of the aircraft. I wondered if it was normal, whether it was just exhaust fumes."
The House of Commons Petitions Committee has said they will keep an eye on the petition and are concerned about fraudulent signatures.