Why floor residue differs from direct consumption
Mayonnaise on the floor has already spread thin and possibly mixed with dust or debris—your terrier likely ingested less than what was originally dropped. At 4 kg, his small body weight makes portion control critical, but the diluted nature of floor spills works in your favor here. The 45-minute head start means if fat absorption was going to cause immediate issues, you'd probably see signs already.
Check where he found it—was this a fresh spill or dried residue? Older mayo loses some oiliness as fats separate and soak into surfaces. That actually reduces the effective dose he consumed, though it's still wise to monitor.
The size-to-fat ratio in tiny dogs
Terriers have hearty appetites but compact digestive systems. What seems like 'just a lick' to a larger dog represents a more substantial percentage of his daily fat intake. Thankfully, one modest exposure rarely triggers pancreatitis unless other risk factors exist.
His metabolism is already processing what he ate—the lack of vomiting so far suggests his body is handling it. Watch for subtle signs like lip-smacking or restless pacing, which can precede nausea in small breeds. These would typically appear within three hours if they're going to occur at all.
When kitchen cleaning becomes prevention
Your next steps matter more than the vet right now. Use a degreaser on that floor spot—dogs remember tasty finds and will revisit the area. For the next few meals, offer his regular kibble without rich toppers to let his system normalize.
Prevent access to the kitchen for 24 hours unless supervised. Small dogs are notorious for finding every crumb, and a second helping could tip the scales from harmless to problematic. If he starts sniffing obsessively where the spill was, redirect him with a safe chew toy.
Thresholds for when to call the vet
At his size, repeated small exposures are riskier than one isolated incident. If this becomes a weekly occurrence, the cumulative effect could strain his pancreas. For today's single event, only persistent vomiting or a hunched posture would justify an urgent visit.
Note his water intake—drinking more than usual can signal his body's working to process the fat. One extra bowl isn't alarming, but if he's constantly at the water dish over the next six hours, that's worth mentioning to your vet. Right now, his normal behavior suggests he's weathering this just fine.
The full verdict, portion guidance and serving notes are collected on the Mayonnaise food facts page.