Two scoreboards for a Westie diet change
Move your West Highland White Terrier onto the new diet over a week to ten days, blending it into the familiar food in stages, and score each stage on two measures at once: how the stools look, and how the skin behaves. That second scoreboard is what makes a Westie transition different from most. Westies carry a breed-wide reputation for reactive, itchy skin, and food is one of the variables owners and vets examine when a Westie is scratching. If you change the food, the treats, and the chews in the same fortnight and the itching changes, nobody knows which change did it. One variable at a time turns the transition into clean information.
Terrier appetite, terrier digestion
A Westie is a small terrier with a terrier's confidence: many eat readily, some develop firm views about a changed bowl, and most will let you know. Their digestion is generally sturdy but a full overnight swap can still loosen stools, and in a small dog each stage jump is proportionally large, so blend in modest steps. Mix the new food thoroughly through the old so your Westie cannot simply harvest the familiar pieces — terriers are practical creatures and will absolutely eat around an unmixed newcomer if the geometry allows it. Keep portions measured to the dog's condition; a Westie who gains weight scratches no less and feels worse for carrying it.
The staged blend, with a skin diary alongside
Start with about a quarter new food for two or three days, then half and half, then mostly new, then all new, holding any stage where stools soften. Alongside the blend, keep a brief daily note: stool quality, any scratching, paw licking, ear shaking, or rubbing, and whether it is more or less than the dog's usual background level. A day or two of mild adjustment is normal; a clear step-change in itching that arrives with a stage increase and fades when you step back is a pattern worth having in writing rather than in memory. Keep everything else — treats, chews, grooming routine — boringly identical while the food changes, so the diary's evidence stays clean.
If your Westie votes against the new food
Meet refusal the terrier way: calmly and without negotiation theatre. Put the blend down at the usual time, lift it after a set interval, and offer the same blend at the next meal. Do not disguise the new food under increasingly exciting toppings, because a Westie who is itchy on a diet needs the diet readable, and toppings muddy both the flavour lesson and the skin evidence. Warming the mix slightly or adding a splash of warm water can make it smell more inviting, which is legitimate persuasion. Most Westies accept a reasonable food within a meal or two once it is clear the kitchen is not taking counter-proposals.
When itching or digestion needs the vet's eye
Contact your vet if loose stools persist beyond a couple of days on a stepped-back blend, if vomiting repeats, if there is blood in the stool, or if a Westie stops eating for more than a day. Skin signs earn a call on their own track: scratching that breaks the skin, sore or smelly ears, hair loss, or itching that keeps escalating across stages should be examined rather than blamed on the food from the armchair — skin trouble in this breed has many possible drivers, and a vet can sort them in a way a food diary alone cannot. Bring the diary anyway: blend stages dated against itching notes, kept in KinsLe through Care Teams with each feeding confirmed and timestamped, is exactly the evidence that makes that appointment productive.