Animal welfare charity Dogs Trust has said that more than 16,000 dogs have been cared for at its 18 UK centres in the past 12 months.
It has launched its festive campaign, A Dog Is For Life, Not Just For Christmas, to drive home the message that potential owners should carefully consider what is involved before getting a pet.
The campaign discourages giving an animal as a present and in line with this, the Dogs Trust does not rehome any dogs between December 22 and 29, or until January 2 at its centres in Scotland.
Some of the excuses used by dog owners getting rid of their pets have been disclosed, including "my dog doesn't match the sofa" and "he isn't as cute as when I first got him".
At the Dogs Trust's Glasgow rehoming centre in Uddingston, South Lanarkshire, a litter of labrador/collie-cross puppies were recently brought in after their mother gave birth unexpectedly.
The original owners managed to give four of the eight away to homes, but called on the Dogs Trust to help rehouse the remainder of the six-week-old litter, whom staff have named Piper, Paige, Phoebe and Pru.
The Glasgow centre cares for around 1,200 dogs each year and usually manages to rehome about 1,000 of them.
At the charity's other Scottish centre, in West Calder, West Lothian, one of the reasons an owner gave for bringing back a pet was because it smelled "of dog".
Other reasons given at centres around the UK have been: "He keeps scaring the goldfish"; "he snores really loudly", "he can't do any tricks"; "my dog keeps passing wind".
The Dogs Trust said some are handed in "just for being dogs" and the charity said it is is bracing itself for the latest influx of unwanted presents.