I'm not a vet but if it is 100% sure it's just orange fibres that the cat ate, then I'd be shocked if there were any serious effects.
Of course it's that 5% doubt that kills us.
here's what the SPCA says
http://www.aspca.org/pet-care/animal...-plants/orange
ORANGE
Scientific Name: Citrus sinensis
Toxicity: Toxic to Dogs, Toxic to Cats, Toxic to Horses
Toxic Principles: Essential oils and psoralens
Clinical Signs: Vomiting, diarrhea, depression; potential photosensitivity
(If your pet ingested this plant, contact your local veterinarian or the ASPCA Animal Poison Control Center at 888-426-4435.*
* A $65 consultation fee may apply.)
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