He recommends keeping your pet out of the bedroom, and closets in particular.

CNN: What to do if you're allergic to your pet

Davidson suggests some silly examples like taxes on keeping a pet, neglecting your yard, playing a musical instrument, and singing in the shower.

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This does not include the often high costs of taking back those now mature animals from buyers not able to live up to keeping their pet.

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Bandai, a Japanese toy company, made millions of dollars by transferring the precepts of pet-keeping to the electronic world with tamagotchi.

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Though a great enthusiast for all things crocodile-related - he once seriously considered the logistics of keeping one in his home as a pet - Packham says humans always need to be on their guard when in the vicinity of such animals.

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If families aren't willing to remove a pet, the next best thing is to isolate the pet from allergic family members as much as possible, by keeping it outdoors, or at least out of bedrooms.

CNN: What to do if you're allergic to your pet

The orders mean pet owners can be fined for failing to remove dog faeces, not keeping a dog on a lead and allowing a dog to enter land from which dogs are excluded.

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Hundreds of iguanas sold in pet stores are being let loose in Los Angeles because their owners have grown tired of keeping them.

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