Why a 4 kg cat's size matters with seed ingestion
Your cat's small body weight makes her more vulnerable to potential toxins per bite compared to larger animals. While the cooked quince flesh itself poses little risk, the seeds she consumed contain compounds that could theoretically release cyanide if thoroughly chewed. Thankfully, cats typically don't grind seeds as effectively as humans do when eating, which greatly reduces this risk.
For a cat her size, the greater immediate concern is mechanical irritation from the seeds' hard shells passing through her digestive system. Watch for signs like excessive licking of lips, repeated swallowing, or stretching her neck - these can indicate throat discomfort from seed fragments. The seeds may also cause mild stomach upset as they move through.
What the first 12 hours after ingestion may bring
Within the first few hours, you might notice your cat acting slightly off - perhaps less interested in her regular food or more lethargic than usual. Some cats will vomit once or twice as their stomach tries to expel the unfamiliar material. This alone isn't necessarily alarming unless it persists beyond 6-8 hours or contains blood.
More concerning would be signs like difficulty breathing, bright red gums, or loss of coordination, though these are extremely unlikely from the small amount described. Focus your monitoring on gastrointestinal signs and general behavior changes. If she's still acting normally by the 12-hour mark, the risk window has likely passed.
How cooked versus raw quince affects risk
The fact that your cat ate cooked rather than raw quince slightly reduces the potential risks. Cooking breaks down some of the tougher plant fibers, making the flesh easier to digest. However, heat doesn't destroy the compounds in seeds that could release cyanide if crushed - it only affects how readily those compounds might be released during digestion.
On the positive side, cooking often makes seeds slightly softer, which may reduce their potential to cause mechanical irritation as they pass through the digestive tract. That said, even cooked seeds retain enough hardness to potentially cause minor issues, especially for a small cat's delicate system.
When to transition from watching to calling the vet
Continue observing your cat closely for the next 24 hours, though most issues would appear within the first 8-12 hours if they're going to occur. If she shows only mild, transient signs like a single episode of vomiting or slightly soft stool, you can likely manage this at home with monitoring and by ensuring she stays hydrated.
However, if she develops persistent vomiting (more than two episodes), won't eat her regular food by the next mealtime, seems unusually lethargic, or shows any neurological signs, contact your vet promptly. These would indicate either significant digestive irritation or, in extremely rare cases, possible cyanide effects from thoroughly chewed seeds that require professional intervention.
The full verdict, portion guidance and serving notes are collected on the Quince food facts page.