Raw Eggs (regular feeding)

How Much Is Dangerous

Not applicable in the acute-toxin sense used elsewhere on this list — the biotin deficiency risk specifically is cumulative, building up from regular feeding over weeks to months, rather than resulting from any single occasional exposure.

Symptoms

• From biotin deficiency specifically, developing with regular feeding over time: dull, thinning, or poor-quality coat, and various skin problems
• From bacterial contamination, which is a risk with any single raw egg regardless of feeding frequency: vomiting, diarrhea, lethargy, and fever — the standard signs of foodborne illness in any species

Time to Symptoms

Bacterial illness, if it occurs: within hours to a couple of days of the contaminated egg being eaten. Biotin deficiency: develops gradually over weeks to months of regular raw egg feeding as part of the diet, not from any single meal.

First Aid Steps

• For an isolated raw egg ingestion — for instance, a cat that manages to steal and eat a raw egg off a counter — monitor for gastrointestinal upset as you would with any foodborne illness risk, without particular concern about biotin deficiency from a single incident
• For a cat whose regular diet intentionally includes raw eggs, discuss balanced nutrition with a veterinarian — cooking the eggs eliminates both the avidin/biotin-binding concern and the bacterial contamination risk while still providing the same protein nutritional value

What Not To Do

• Do not feed raw eggs as a regular, ongoing part of a cat's diet without veterinary guidance on how to balance this appropriately
• Do not assume cooking eggs removes their nutritional value for the cat — cooked eggs remain a perfectly good protein source while avoiding both concerns described above

Veterinary Treatment

Supportive care for any acute gastrointestinal illness from bacterial contamination; correction of diet composition, and biotin supplementation if needed, to resolve any biotin deficiency that has developed from a pattern of regular raw egg feeding over time.

Toxic Compound

Avidin, a glycoprotein present in raw egg white that binds biotin (vitamin B7) with extremely high affinity and prevents its absorption in the digestive tract. This represents a nutritional deficiency risk that develops from regular or repeated feeding over time, not an acute poisoning event from eating a single egg. Raw eggs also separately carry a real risk of Salmonella and E. coli contamination — a distinct food-safety concern from the avidin/biotin mechanism, relevant even to a cat eating raw egg only occasionally.